Lecture 4_Shallow foundations_bearing capacity (1)

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建筑工程专业英语课件专业英语第3单元

Text A Components of a Building
Construction of Foundation Foundation is a very important part of a building. Foundation
engineering is a special subject. A foundation engineer should know how to examine the soil profile and arrive at a suitable foundation. The following are some of the different types of foundation generally used:
1. Planning the orientation, layout and dimension of the rooms of the building
2. The preparation of the features to make the building attractive Work of this nature for small buildings may be taken by nonarchitects also. However, the construction of a building should always be carried out under the supervision of a qualified person. We will now briefly examine the construction of the different components of buildings.
Text A Components of a Building

2024浙江一月英语读后续写分析与范文

2024浙江一月英语读后续写分析与范文Title: Reflections on the January English Reading Comprehension and Writing Section in Zhejiang Province, 2024 The January English reading comprehension and writing section in Zhejiang Province for 2024 presented a diversearray of texts and prompts, challenging candidates to engage critically with various themes and subjects. In this analysis, we delve into the structure of the exam, the types of questions posed, common pitfalls, and strategies foreffective response, culminating in a sample essay that demonstrates a comprehensive understanding of the task.**Exam Structure:**The exam typically comprises multiple reading passages followed by corresponding comprehension questions and awriting task. Passages may vary in length and complexity,covering topics ranging from social issues to literary excerpts.**Types of Questions:**Comprehension questions often assess candidates' abilityto infer meaning, identify main ideas, analyze literary techniques, and evaluate arguments. These questions requirenot only a grasp of surface-level content but also deeper comprehension and critical thinking skills.**Common Pitfalls:**One common pitfall is rushing through passages and questions without fully understanding the nuances of the text. Additionally, overlooking key details or misinterpreting information can lead to inaccurate responses. In the writing section, failing to structure arguments coherently or neglecting to support claims with evidence may result in a weaker essay.**Strategies for Effective Response:**To excel in the reading comprehension section, candidates should practice active reading techniques such as annotating the text, summarizing main points, and making connections between ideas. For the writing task, outlining a clear thesis statement, organizing arguments logically, and incorporating relevant examples and evidence are essential strategies.**Sample Essay:**Prompt: "Discuss the impact of technology on interpersonal relationships in the 21st century, providing examples to support your argument."In the 21st century, technology has revolutionized the way we communicate, profoundly influencing interpersonal relationships. While proponents argue that technology enhances connectivity, critics raise concerns about its detrimental effects on genuine human interaction. This essay contends that while technology facilitates convenience andglobal communication, it also poses challenges to meaningful interpersonal relationships.One significant impact of technology on interpersonal relationships is the erosion of face-to-face communication skills. With the prevalence of digital communication platforms, individuals rely heavily on text-based interactions, diminishing opportunities for in-person conversations. As a result, essential social skills such as interpreting nonverbal cues and expressing empathy may deteriorate, hindering the development of meaningful connections.Furthermore, the curated nature of online personas often leads to superficial relationships. Social media platforms promote self-presentation and validation-seeking behavior, fostering an environment where individuals prioritize projecting idealized versions of themselves over authentic interactions. Consequently, relationships built on shallowfoundations lack depth and sincerity, undermining the essence of genuine human connection.Moreover, technology can create barriers to intimacy and emotional expression. The convenience of instant messagingand social media may discourage individuals from engaging in meaningful conversations that require vulnerability and emotional openness. Consequently, relationships may become transactional, lacking the emotional depth necessary for sustained connection and intimacy.However, it is essential to acknowledge that technology also facilitates connectivity and fosters relationshipsacross geographical boundaries. Through video calls, social networking sites, and online communities, individuals can maintain connections with friends, family, and peersregardless of distance. Additionally, technology provides avenues for marginalized groups to find community and support, enriching their interpersonal experiences.In conclusion, while technology offers unprecedented opportunities for communication and connectivity, its impact on interpersonal relationships is multifaceted. While acknowledging the benefits of technology in facilitating global connections, we must also address its challenges, including the erosion of face-to-face communication skills, the proliferation of superficial relationships, and barriers to emotional intimacy. Ultimately, fostering genuine interpersonal connections in the digital age requires a mindful balance between leveraging technology's advantages and preserving the essence of human interaction.In summary, the January English reading comprehension and writing section in Zhejiang Province for 2024 demanded a nuanced understanding of various texts and themes, coupled with critical thinking skills and effective communication abilities. By employing active reading strategies, avoiding common pitfalls, and structuring coherent responses,candidates could navigate the exam successfully and articulate insightful analyses and arguments.。

基底原始记录基底地质情况范文

基底原始记录基底地质情况范文英文回答：General Site Geotechnical Report.Project: New Construction Residential Development.Location: [Address]Client: [Client Name]Date: [Date]1. Introduction.This geotechnical report presents the results of a subsurface investigation performed at the site of a proposed new construction residential development. The purpose of the investigation was to evaluate the subsurface conditions at the site and to provide geotechnicalrecommendations for the design and construction of the proposed development.2. Site Description.The site is located at [address] and consists of [number] acres of undeveloped land. The site is currently vacant and covered in vegetation. The topography of thesite is relatively flat, with a gentle slope to the east.3. Subsurface Investigation.The subsurface investigation included the following:Borings: Four borings were drilled to depths ranging from 50 to 75 feet below the ground surface.Sampling: Soil samples were collected from the borings at regular intervals.Laboratory Testing: The soil samples were tested in the laboratory to determine their physical and engineeringproperties.4. Subsurface Conditions.The subsurface conditions at the site generally consist of the following:Topsoil: The topsoil is typically dark brown to black in color and consists of organic matter, silt, and clay. The topsoil is typically 12 inches thick.Clay: The clay is typically brown to gray in color and is stiff to hard in consistency. The clay is typically 20 to 40 feet thick.Sand: The sand is typically brown to yellow in color and is fine to medium grained. The sand is typically loose to dense in consistency. The sand is typically 30 to 50feet thick.5. Geotechnical Recommendations.Based on the subsurface conditions at the site, the following geotechnical recommendations are made:Foundations: The proposed buildings should be supported on shallow foundations, such as spread footings or mat foundations. The footings should be placed at a depth of at least 24 inches below the ground surface.Excavations: Excavations for the proposed buildings should be sloped or braced to prevent collapse. The excavations should be kept as dry as possible to prevent sloughing.Grading: The site should be graded to provide positive drainage away from the proposed buildings. The grading should be completed in accordance with the approved grading plan.6. Limitations.This report is based on the subsurface conditions observed at the boring locations. Variations in thesubsurface conditions may exist between the boring locations. The recommendations presented in this report are based on the assumption that the subsurface conditions at the site are typical of those encountered at the boring locations.中文回答：基底原始记录基底地质情况。

汉译英基础建筑

汉译英基础建筑基础建筑（Foundation Construction）是建筑学中的一个重要领域，是指用于支撑建筑物本身以及应对来自地面和周边环境的各种力和荷载的一系列工程和结构。

基础建筑主要包括浅基础和深基础两种类型。

浅基础是指建筑物承受轻荷载时所采用的基础形式，包括板基础、条基础、垫石基础等。

深基础则是建筑物承受重荷载时所采用的基础形式，包括钻孔灌注桩、螺旋桩、钢管桩等。

在基础建筑中，土工材料的选用和处理也是一个重要问题，对基础的安全性和稳定性有着重要影响。

Basic construction is an important field in the study of architecture. It refers to a series of engineering and structures used to support the building itself and to cope with various forces and loads from the ground and surrounding environment. Basic construction mainly includes two types: shallow foundations and deep foundations. Shallow foundations are used for light loads and include slab foundations, strip foundations, and pad stone foundations. Deep foundations are used for heavy loads and include drilled-injection piles, helical piles, and steel pipe piles. In basic construction, the selection and treatment of geotechnical materials is also an important issue that has a significant impact on thesafety and stability of the foundation.。

香港理工大学殷建华老师之PPT

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Essential References: (1) Das, Braja M. (2007). Principles of Foundation Engineering (6th edition), Thomson, United States (ISBN 0-534-40752-8)
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Lecture 6: Sheet Pile Walls (Chapter 6-Das) 板樁墻
深基坑开挖与支护设计
殷建华
The Department of Civil & Structural Engineering The Hong Kong Polytechnic University, Hong Kong, China
1
Outline of Lectures by JH YIN:
Lecture 1: Subsoil Exploration (Chapter 2-Das) Lecture 2: Shallow Foundations (Chapter 3-Das) Lecture 3: Mat Foundations (Chapter 4-Das) Lecture 4: Lateral Earth Pressure and Retaining Walls (Chapter 5-Das) Lecture 5: Sheet Pile Walls (Chapter 6-Das) Lecture 6: Braced Cuts (Chapter 7-Das) Lecture 7: Pile Foundations (Chapter 8-Das) Lecture 8: Soil Improvement and Ground Modification (Chapter 11Das plus others)

奠基需要注意的问题

奠基需要注意的问题英文回答：When it comes to laying the foundation, there are several important factors that need to be taken into consideration. First and foremost, it is crucial to ensure that the ground is properly prepared before starting the construction process. This involves conducting a thorough soil analysis to determine its stability and load-bearing capacity. By doing so, potential issues such as soil settlement or shifting can be identified and addressed beforehand.Another key aspect to consider is the type of foundation that is most suitable for the specific project. There are different types of foundations, such as shallow foundations and deep foundations, each with its own advantages and disadvantages. For instance, shallow foundations are typically used for lighter structures, while deep foundations are more suitable for larger andheavier buildings. The choice of foundation will depend on factors such as the soil conditions, the size and weight of the structure, and the local building codes and regulations.Furthermore, it is important to ensure that the foundation is properly designed and constructed. This involves hiring a qualified engineer or architect who can create a detailed plan that takes into account factors such as the load requirements, the structural design, and the local building codes. The foundation should be constructed using high-quality materials and techniques to ensure its durability and stability.In addition to these technical considerations, thereare also practical aspects that need to be taken into account. For example, it is important to consider the accessibility of the construction site and the availability of necessary equipment and materials. It is also crucial to coordinate with other contractors and professionalsinvolved in the project to ensure a smooth and efficient construction process.中文回答：在进行奠基工作时，有几个重要因素需要考虑。

桥梁工程毕业论文英文

桥梁工程毕业论文英文Title: Analysis and Design of Bridge StructuresAbstract:Bridge engineering is an integral part of civil engineering and plays a crucial role in connecting communities and facilitating transportation. The purpose of this thesis is to analyze and design bridge structures, focusing on key components such as foundations, superstructures, and substructures. The analysis includes evaluating the structural behavior and load carrying capacity through the utilization of various analytical tools. Furthermore, the design phase encompasses selecting suitable materials and designing components to meet safety and durability requirements. The study serves as a comprehensive guide to understanding the principles and processes involved in bridge engineering.1. IntroductionBridges are vital infrastructure that connects people, places, and economies. The study of bridge engineering involves the application of core principles like physics, materials science, and mathematics todesign and construct safe and efficient bridge structures. This thesis aims to provide an overview of the analysis and design principles involved in bridge engineering.2. Structural AnalysisThe analysis of bridge structures is crucial to ensure their safety and functionality. This chapter presents various analytical techniques for evaluating bridge behavior. The use of finite element analysis, structural modeling, and computer-aided design software is discussed in detail. Different load types and load combinations are also considered to determine the resilience and load carrying capacity of the bridge.3. Foundation DesignThe foundation is a critical component of any bridge structure, as it transfers the loads from the superstructure to the underlying ground. This chapter explores various foundation types, such as shallow foundations, deep foundations, and pile foundations. Design considerations, including soil mechanics, bearing capacity, settlement analysis, and groundwater conditions, are discussed. The use ofgeotechnical engineering software to simulate and optimize foundation design is also explored.4. Superstructure DesignThe superstructure refers to the portion of the bridge that supports the traffic loads and transfers them to the substructure. This chapter discusses the different types of superstructures, including beam bridges, truss bridges, and arch bridges. The selection of materials, such as concrete, steel, and composite materials, is analyzed based on their structural properties and cost-effectiveness. The design process incorporates the calculation of load distribution, structural stability, and deflection limits.5. Substructure DesignThe substructure comprises the bridge piers, abutments, and retaining walls, which provide support to the superstructure. This chapter focuses on the design considerations for substructures, including the selection of suitable materials, analysis of load distribution, and evaluation of stability against various forces and environmental conditions. Design principles for reinforced concrete and masonry substructures are explored, along with mitigationstrategies for potential issues such as scour and seismic activity.6. Safety and DurabilityEnsuring safety and durability is of utmost importance in bridge engineering. This chapter discusses the necessary steps for evaluating the safety of bridge structures, including factor of safety calculations, failure mode analysis, and risk assessment procedures. The discussion also includes guidelines for maintenance and inspection to ensure long-term performance and durability.7. ConclusionThis thesis provides an in-depth analysis and design framework for bridge structures. By comprehensively exploring the key components of bridges, including foundations, superstructures, and substructures, it provides valuable insights into the principles and processes involved in bridge engineering. The knowledge gained from this study will contribute to the safe and efficient design and construction of future bridge projects.。

那一刻我长大了下围棋英语作文范文

全文分为作者个人简介和正文两个部分：作者个人简介：Hello everyone, I am an author dedicated to creating and sharing high-quality document templates. In this era of information overload, accurate and efficient communication has become especially important. I firmly believe that good communication can build bridges between people, playing an indispensable role in academia, career, and daily life. Therefore, I decided to invest my knowledge and skills into creating valuable documents to help people find inspiration and direction when needed.正文：那一刻我长大了下围棋英语作文范文全文共3篇示例，供读者参考篇1The Moment I Grew Up Playing GoLooking back, I can pinpoint the exact moment when I transitioned from a carefree child to a more mature, responsible young adult. It wasn't any major life event or epiphany - ithappened over a simple board game called Go. This ancient Chinese strategy game, with its minimalist black and white stones on a gridded board, turned out to be the catalyst for my personal growth and maturation.I was first introduced to Go by my grandfather when I was around 8 years old. A passionate player himself, he tried to teach me the basics, but I readily dismissed it as an "old person's game." The rules seemed overly complex, and the lack of a defined objective or means of winning confused my young mind, used to straightforward games with clear-cut goals. Little did I know then how profoundly this game would impact me just a few years later.It wasn't until I was 11 that I rediscovered Go, quite by chance. I was rummaging around in my grandfather's study when I stumbled upon his battered leather Go set, lovingly preserved. Curiosity piqued, I set up the board and began tinkering with the stones, trying to make sense of the seemingly chaotic array of patterns before me. My grandfather walked in, pleasantly surprised at my newfound interest, and patiently explained the nuances of the game once more. This time, something clicked.I became obsessed, playing game after game, my mind challenged and stimulated in entirely new ways. Go was a puzzle, an intricate dance where every move had consequences that rippled across the board. Battles for territory raged, and corners were fortified or invaded based on calculated strategy. I pored over books and watched online videos, determined to improve through relentless study.More than just the strategic aspects, I found myself drawn to the philosophy and values intrinsic to Go. Concentration, patience, respect for one's opponent, an acceptance that perfection is impossible - these tenets resonated deeply within me. I came to appreciate the profound beauty in Go's simple elements and timeless traditions. Each handcrafted stone had a weight, a story, a connection to the ancients who played this very game centuries ago.As my skills progressed, I began entering regional tournaments, my childish arrogance quickly tempered by losses against older, wiser players. I learned humility in defeat but also perseverance, spending hours analyzing games to pinpoint weaknesses in my tactics. A lousy loser as a child, I slowly learned grace and sportsmanship, and formed deep friendships over theyvory pavements. I discovered that losing was not aboutfailure, but an opportunity to improve through diligentself-reflection.The more I played, the more I recognized profound parallels between Go and life itself. The opening moves represented the foundations we build, the corners we stake out as our values and beliefs. The middle game was the tumultuous journey where battles are waged, risks taken, mistakes made but overcome through resilience. And the endgame, a gradual crystallization of our efforts, a reckoning of the consequences of everylong-forgotten choice.From these revelations blossomed a more thoughtful, strategic approach to my own life. I started making more calculated decisions instead of impulsive choices. I learned to consider every angle, mapping out possible paths and anticipating pitfalls. A poor student before, my grades improved as I applied the same studious dedication to academics as I did to Go. Simple pleasures like seeing a beautiful sunrise or cooking a nourishing meal brought me joy, as I embraced Go's philosophies of appreciating the present moment and finding contentment in modest acts.My priorities shifted, and I forged an unshakeable focus that helped me navigate the turbulent waters of adolescence. Whenfaced with peer pressure to drink or act recklessly, I found clarity in Go's wisdom - indulgences were fleeting distractions that disrupted my tranquil mind and sound judgement. While friends blindly pursued toxic relationships based on shallow infatuation, I remained patient, recognizing the importance of laying strong foundations before branching outwards.Perhaps my most significant growth was in cultivating respect for others, particularly those with different backgrounds or perspectives. Over the Go board, I learned to set aside preconceptions, authentically engage with my opponents, and appreciate their unique styles. In the wider world, thisopen-mindedness helped me connect with a remarkably diverse group of individuals who broadened my worldview. I formed deep bonds with those from all walks of life, united by our shared love for this elegant game.Now, as I prepare to graduate high school, I can trace so much of who I am today back to those pivotal moments bent over the vyvorn board, battling for spheres of influence. Go imparted strategic thinking, patience, resilience in the face of setbacks, and a mature sense of confidence not born of arrogance, but quiet self-assurance. Most importantly, it instilled in me a deep respect for the intangible but powerful connectionsthat bind all people together through our timeless human experiences.While my peers fret about career paths or future relationship prospects, I find solace in Go's wisdom - that some things cannot be forced, but must unfurl at their own natural pace, with patience and care. I know that just as every game began with the first purposeful placement of stone on wood, every meaningful journey starts with a single step, a choice to fully commit oneself. No matter which ivory path I traverse, the principles of this ancient game will forever light my way, reminding me to appreciate every moment, learn from every misstep, and play with passion, integrity and respect for all I encounter.So while the moment of my true growth into adulthood may seem an unlikely one over a game board, I know that it was Go that transformed me. It was in those quiet battles, surrounded by the gentle clack of polished stones, that a child's restless spirit found focus, and the seeds of wisdom blossomed into personal maturity. For that profound gift, I remain forever grateful to this timeless game and its legacy of cultivating enlightened minds.篇2The Moment I Grew Up at the Game of GoThey say that there are moments in life that change you, that force you to grow up before you're ready. For me, that moment came not from a life-altering tragedy or traumatic event, but rather from a quiet afternoon playing the ancient game of Go. It was a sunny Saturday, and I had gone over to my friend David's house to hang out like we did most weekends. David's dad was really into Go, and he had been trying to teach us how to play for a while.At first, I'll admit, I didn't take it too seriously. Go just looked like a bunch of black and white stones being placed on a grid. What was the big deal? I was more interested in playing video games or watching movies – typical teenage stuff. But David's dad was persistent, and gradually I started to understand the depth and beauty of this seemingly simple game.That fateful Saturday, David and I agreed to play a game against each other, with his dad observing and offering advice. The early moves went by quickly as we raced to stake out territory on the board. I was starting to feel confident, having beaten David most of the times we had played so far.But then something shifted. David started playing more patiently, thinking several moves ahead. His stone placements became more purposeful, methodically mapping out influenceacross the entire board. I began to feel outmaneuvered, my earlier lead gradually slipping away.David's dad watched silently, his eyes tracing the diverging patterns of black and white across the grid. Periodically, he would make a thoughtful comment: "Interesting move..." or "The game is becoming more complex..." Sweat began to bead on my forehead as I struggled to find a way to claw back the advantage.With each placement, the board morphed from a simple grid into a battlefield streaked with intricate formations. Armies of black and white stones stretched across the space, clashing where our influences collided. I started seeing phantom pieces in my mind, mapping out attack routes, defensive formations, stunts of brilliant sacrifice.Two hours melted away as we entered a zone of pure concentration. The rest of the world faded – there were only the stones, theboard, and the delicate dances of strategy coalescing between David and me. I had never experienced a sense of focus like this before in my life.Finally, after what felt like an eternity, I raised my head, blinking in the afternoon light. David leaned back, running a hand through his hair. His dad smiled knowingly. "What did you think of that game, boys?"I opened my mouth, then closed it. The words wouldn't come. Something profound had just happened, but I couldn't articulate exactly what. All I knew was that a shift had occurred inside me. The game of Go had forced me to raise my mental efforts to an entirely new level. I had been challenged, stretched to my limits, and in responding, some reservoir of discipline and maturity had been tapped.From that day forward, I approached all aspects of my life with a renewed seriousness of purpose. My grades improved as I applied the intense focus from Go to my studies. I became a better listener, more patient and calculating when having conversations. A newfound work ethic emerged as I recognized the value of perseverance.Go had cracked open something inside my mind – not in a traumatic way, but almost...surgically. It was as if a seed of pure cognitive potential had been unlocked, and now it was blossoming in ways I could never have anticipated.Over the years that followed, I continued playing Go, getting incrementally better, but also losing plenty as the game constantly unveiled new layers of depth and wisdom. And with each game, each win or loss, I felt myself maturing a little more. Experiencing the ebb and flow of advantage, learning torebound from setbacks, developing the equanimity to confront any situation with a clear mind – these were all lessons Go taught me.Of course, David's dad was thrilled that we had embraced his favorite game so wholeheartedly. In many ways, he had become a third mentor to me alongside my parents. He used to joke that Go was an ancient tool of the wise men for shaping young minds. At first I thought he was being melodramatic, but I came to understand exactly what he meant.Today, as I prepare to graduate high school and take my next stepinto adulthood, I can't help but look back on that fateful afternoon with immense gratitude. In those few hours, I underwent a profound metamorphosis, shedding my childish obliviousness and being reborn with a more expansive mindset. The game of Go was the catalyst for my mental chrysalis, preparing me for the challenges and complexities of adult life.So while my friends might reminisce about life-changing romances or family traumas, I will always remember the moment I grew up over that grid of intersecting lines, moving black and white stones with increasing intentionality, and finally emerging from our trance reborn as a more aware, disciplined, and frankly,kickass human being. Thank you David's dad, and thank you, Go. You showed this kid what it really means to play.篇3The Moment I Grew Up Playing GoIt was just an ordinary summer day like any other. The sun was high in the bright blue sky, baking the neighborhood in its warmth. The chirping of birds and the occasional buzz of a lawnmower provided the soundtrack to the lazy afternoon. I was lying on my bed, staring at the ceiling fan lazily spinning round and round, desperately trying to think of something to fill the endless hours stretching ahead. That's when I heard a knock at my door."Johnny? You in there?" It was my grandfather's voice. "Come on down to the living room for a bit."I let out an exaggerated sigh, as dramatic as only atwelve-year-old can manage. "What is it, Grandpa?" I hollered back, dragging out the last word to really emphasize how bored and inconvenienced I felt.There was a pause before he responded. "It's a surprise. Just come down here."Curiosity got the better of me. I hauled myself up off the bed and trudged downstairs, steeling myself for whatever dull activity my grandpa had cooked up to relieve his own boredom. But when I entered the living room, I saw something quite unexpected.On the coffee table was a wooden board lined with the most intricate hand-carved grids I'd ever seen. Beside it were two bowls filled with smooth stones, one bowl containing black stones and the other white. My grandpa was seated on the floor, hunched over studying the strange setup intently."What's all this?" I asked, unable to hide the bewilderment in my voice.Grandpa looked up at me with a glimmer in his eyes. "Do you know what this is, Johnny?"I shook my head. He smiled that warm, wrinkly smile of his."This is a game of strategy older than chess. Older than most games, in fact. It originated in ancient China over 2,500 years ago. It's called 'Go'."He said the name with such reverence, you'd have thought he was talking about some sacred ritual instead of a board game.But Grandpa always did have a Air of gravitas about him. I was intrigued despite myself."How do you play?"And so he taught me. He explained the basics of taking territory by surrounding empty intersections with stones. He showed me the importance of building flexible formations that could stay connected or break apart as needed. Simple rules, but with profound depth underneath. I played a few games against him, my hasty and impatient placements no match for his prudence and foresight. Each time I lost, I grew more determined to unlock the secrets of this ancient game.From that day forth, I became obsessed. My grandpa had awoken a ravenous hunger in me, one that could only be sated by studying Go tactics and strategy. I pored over books and watched video lectures, soaking up every bit of wisdom the Go masters had to offer. Grandpa and I would play for hours, reviewing each move and its ramifications over steaming mugs of tea.At first, the losses kept coming. But gradually, ever so gradually, I started catching up to him. What had begun as a lighthearted activity evolved into an intense mental duel, each of us probing for the slightest inaccuracy to exploit. I'll never forgetthe first time I finally beat him - the look of shock and immense pride that washed over his weathered face when he realized his young pupil had surpassed him.As I grew older and entered my teenage years, my dedication to Go only deepened. What had started as a game became a metaphor for life itself. I came to appreciate the balance between territory and influence, attack and defense, building a relentless onslaught while leaving enough solid foundations to ensure safety. Every phase of the game contained profound lessons about finding harmony between opposing forces.When I made missteps on the board, I realized how easily one small mistake could spiral out of control into a lost battle and potentially the entire war. Go taught me the value of foresight, of mapping out potential scenarios and choosing the most strategically advantageous path. It instilled in me the patience and resolve to play for the biggest territorial gains, even if doing so meant sacrificing stones in the short term.But more than anything, Go revealed to me the sheer complexity of the world we live in. With its staggering number of potential moves and permutations, the game made me aware of how even the smallest decisions and choices we make can havewide-ranging and unforeseeable consequences. It grounded me in a sense of humility and respect for the intricate web of causes and effects weaving through our existence.Most importantly though, Go connected me to my grandfather in a way few other things could. In those long hours across the goban, I came to understand him as more than just a relative, but as a living repository of wisdom and life experience. I soaked up his stories of persevering through hard times and treasuring each precious moment of peace and happiness. He taught me to approach life's obstacles and setbacks with a Go player's mentality - maintain perspective, learn from each loss, and never give up the search for a more perspicacious path forward.When Grandpa passed away during my sophomore year of college, I was devastated. He had been my teacher, my mentor, and one of the most profoundly positive influences in shaping who I had become as a young man. In the wake of that loss, I found solace in our shared love of Go. Each time I unfolded my portable magnetic board, carefully placing the smooth stones across its dreamlike grid, I felt Grandpa's gentle presence beside me.With each game, I grew to appreciate his legacy more and more. Not just the strategies and tactics he had imparted, but the life lessons of resilience, wisdom, and hunting steadfastly for a deeper understanding of this vast and marvelous universe we inhabit. Go for me is no longer merely a game, but a potent reminder of all that is beautiful and meaningful about the human experience. It's about making the most of each turn, savoring the hourglass of life as the sands flutter through the rift. Above all, it's a celebration of the profound connections we can make through humble traditions passed down over millennia.So while to some it may appear just an ancient abstract played out on wooden boards, Go for me will always be the game that helped me grow up. It opened my eyes to a world larger than I could have ever imagined as a bored child that fateful summer day. Grandpa didn't just teach me a game that day, but something far more profound - he gifted me a wise and purposeful path through life itself. And for that, I will be forever grateful to him and the beautifully complex game that became our shared language of understanding.。

结构工程师面试题目

结构工程师面试题目Structure Engineer Interview QuestionsIntroduction:Structure engineering is a crucial field that deals with the design, analysis, and construction of various structures like buildings, bridges, and towers. In an interview for a structure engineering position, candidates are often asked specific technical questions to assess their knowledge and capabilities. In this article, we will discuss some common structure engineer interview questions that can help candidates prepare for their interviews.Question 1: What are the main differences between dead load and live load in structural engineering?Answer: Dead load refers to the static weight of a structure or its components, including the weight of the structure itself, permanent fixtures, and other non-movable elements. On the other hand, live load refers to the dynamic or variable load that a structure is expected to carry due to occupancy, furniture, vehicles, or other temporary factors. Dead loads are constant, while live loads can vary and are considered a transient force.Question 2: Could you explain the concept of structural stability and its importance in engineering?Answer: Structural stability is the ability of a structure to maintain its form and resist collapse under different loading conditions. It ensures that the structure can withstand external forces without failure. Structural stability is a critical factor in engineering as it ensures the safety anddurability of the structure. Without proper stability, a structure can experience excessive deformations or even collapse, posing a threat to human life and property.Question 3: What are the different types of foundation systems in structural engineering?Answer: There are several types of foundation systems used in structural engineering, including:1. Shallow foundations: These foundations are used when the soil has sufficient bearing capacity near the surface. Examples include spread footings and mat foundations.2. Deep foundations: These foundations are used when the soil near the surface cannot support the structure's load. Examples include pile foundations and drilled shafts.3. Retaining walls: Retaining walls are used to support soil or other materials at different elevations. They provide lateral support and prevent soil erosion.Question 4: How do you ensure the structural safety of a building during the design phase?Answer: Ensuring structural safety during the design phase is crucial to avoid risks and potential failures. Some essential steps include:1. Conducting a thorough analysis of the project requirements and understanding the loads and forces acting on the structure.2. Designing the structure with appropriate materials, dimensions, and reinforcements to withstand the expected loads.3. Performing structural analysis using software or manual calculations to verify the design's integrity.4. Conducting regular inspections and quality checks during the construction phase to ensure adherence to the design specifications and industry standards.Question 5: Can you explain the concept of lateral stability in structural engineering?Answer: Lateral stability refers to a structure's ability to resist lateral or horizontal loads, such as wind or seismic forces. It prevents excessive deflection, structural failures, and ensures stability throughout its lifetime. Lateral stability is achieved through various methods, including bracing systems, shear walls, diaphragms, and moment-resisting frames. These elements distribute and dissipate lateral forces, improving the overall stability of the structure.Conclusion:Preparing for a structure engineer interview requires a solid understanding of fundamental principles and concepts in structural engineering. By familiarizing yourself with common interview questions and practicing their answers, you can increase your chances of succeeding in the interview and securing the desired position. Remember to demonstrate your knowledge, problem-solving abilities, and commitment to ensuring the safety and stability of structures in your responses. Good luck!。

教学大纲

《土木工程专业英语》教学大纲一，课程的性质与任务《土木工程专业英语》是开放教育本科土木工程专业的选修课，计4学分，72 学时，开设1学期。

本课程的任务，是使学生能够在普通英语知识的基础上，初步了解专业英语的特点，基本学会借助工具阅读土工专业文章的方法，在一定程度上掌握专业英语的翻译技巧，为更好地从事本专业打下较扎实的基础。

二，资源与媒体1，主教材：《土木工程英语》，惠宽堂等编著，中国建材工业出版社2003年2 月第一版。

2，网上视频点播直录节目3，网上有针对性的教学辅导、平时作业、自测练习、疑难解答等。

三，教学内容与学时分配专业英语语言基础（2学时）选自主教材的下列文章：Reinforced Concrete (1) (6学时)Hazards (6学时)The Available Information (5学时)Bearing Capacity of Shallow Foundations (5学时)Construction Contracts (4学时)Engineer and Economy (6学时)Pavement of Highway and Airport (1) (6学时)Construction Planning (6学时)The Civil Engineering Project (1) (2) (9学时)Concrete Construction (4学时)Cable-stayed Bridge (7学时)Development of Structural Forms for Tall Building (1) (6学时)合计72学时四，学习方法自学为主，面授为辅，相互学习，网上求助。

五，考核方法本课程的考核分形成性考核和总结性考核两部分。

前者主要为平时作业或教师面授时的提问，后者为期末考试。

期末考试为闭卷形式，时间90分钟。

形成性考占课程总成绩的20%，总结性考核占总成绩的80%六，词汇表本词汇表为大纲拟定者精选的土木工程专业英语中常用的专业词汇与普通词汇，共1000个。

新概念英语单词&音标

$第1课0puma / 5pju:mE/spot/ spRt/evidence / 5evidEns/accumulate / E5kju:mjuleit/oblige / E5blaidV/hunt/ hQnt/blackberry / 5blAkbEqi/human / 5hju:mEn/corner / 5kR:nE/trail / tqeil/print / pqint/cling / kliN/convince / kEn5vins/somehow / 5sQmhau/disturb / dis5tE:b/$第2课0equal / 5i:kwEl/vicar / 5vikE/raise / 5qeiz/torchlight / 5tR:tFlait/$第3课0goddess/ 5gRdis/archaeologist / 5a:kiE5lRdVist/Aegean / i:5dVi:En/explore / iks5plR:/promontory / 5pqRmEntEqi/prosperous / 5pqRspEqEs/civilization / 5sivilai5zeiFEn/storey / 5stR:qi/drainage / 5dqeinidV/worship / 5wE:Fip/sacred / 5seikqid/fragment / 5fqAgmEnt/remains / qi5meinz/classical / 5klAsikEl/reconstruct / 5qi:kEns5tqQkt/rest / qest/hip/ hip/full-length / /graceful / 5gqeisful/identity / ai5dentiti/$第4课0manual / 5mAnjuEl/collar / 5kRlE/sacrifice / 5sAkqifais/privilege / 5pqivilidV/dustman / 5dQstmEn/corporation/ 5kR:pE5qeiFEn/0 n.美洲狮v.看出，发现n.证据v.积累，积聚v.使…感到必须n.追猎；寻找；v.打猎n.黑莓人类v.使走投无路，使陷入困境；n.角落n.一串，一系列n.印痕v.粘v.使…信服ad.不知怎么搞的，不知什么原因v.令人不安v.等于n.牧师v.募集，筹(款)n.电筒光n.女神n.考古学家a.爱琴海的v.考察，勘探n.海角a.(经济上)繁荣的，昌盛的n.文明n.楼层n.排水n.祟拜a.宗教的，神圣的n.碎片n.遗物，遗迹，废墟a.(希腊和罗马)古文化的v.修复v.倚放，放置n.屁股，臀部a.(裙衣)拖地长的a.优雅的n.身份a.体力的n.衣领v.牺牲，献出n.好处，特权n.清洁工n.公司。

基于Geant4_的核孔膜生产模拟研究

第38卷第1期2024年2月南华大学学报(自然科学版)Journal of University of South China(Science and Technology)Vol.38No.1Feb.2024收稿日期:2023-09-05基金项目:厦门市青年创新基金资助项目(3502Z20206025)作者简介:张倩影(1990 ),女,工程师,硕士,主要从事核技术应用㊁城市安全评价方面的研究㊂E-mail:skrvvtg@㊂∗通信作者:傅楗强(1990 ),男,助理研究员,博士,主要从事辐射物理与探测技术方面的研究㊂E-mail:fujq12@DOI :10.19431/ki.1673-0062.2024.01.012基于Geant4的核孔膜生产模拟研究张倩影,傅楗强∗(清华海峡研究院(厦门),福建厦门361015)摘㊀要:利用核反应堆产生的裂变重离子碎片辐照固体薄膜,是生产核孔膜的主要方式之一㊂为优化反应堆核孔膜生产工艺参数,给核孔膜生产提供理论指导,本文基于Geant4开发了反应堆生产核孔膜的原理性模拟程序,对铀靶在热中子辐照下裂变碎片的生成及出射物理过程开展模拟,并分析计算了不同厚度下铀靶裂变碎片的出射能量㊁角度分布,从理论上优化了核孔膜生产中的铀靶厚度及固体薄膜厚度㊂结果表明,铀靶厚度为4μm 时裂变碎片出射强度最高;受裂变碎片射程的限制,反应堆生产核孔膜所用的固体薄膜的厚度最大约为8μm ㊂关键词:核孔膜;Geant4;蒙特卡洛模拟中图分类号:TL99文献标志码:A文章编号:1673-0062(2024)01-0090-07Geant 4-based Simulation Study of Nuclear Track-etchedMembrane ProductionZHANG Qianying ,FU Jianqiang ∗(Cross-strait Tsinghua Research Institute,Xiamen,Fujian 361015,China)Abstract :One of the main ways to produce nuclear track-etched membrane is irradiating solid membranes with the fission fragments produced by nuclear reactor.In order to opti-mize the production process parameters of nuclear track-etched membranes and provide theoretical guidance for nuclear track-etched membrane production,a simulation program is developed based on Geant4to simulate the process of nuclear track-etched membrane produced by nuclear reactor.The physical process of generation and emission of neutron-induced Uranium 235fission fragments are studied,and the energy and angular distribu-tions of fission fragments under different thicknesses of the target are analyzed and calculat-ed.The thickness of the Uranium target and solid membrane are optimized theoretically.It9第38卷第1期张倩影等:基于Geant4的核孔膜生产模拟研究2024年2月can be concluded that a4μm thick Uranium target has the highest emission intensity offission fragments.The maximum thickness of the solid membranes is about8μm,which islimited by the range of fission fragments.key words:nuclear track-etched membrane;Geant4;Monte Carlo simulation0㊀引㊀言核孔膜是利用反应堆或加速器产生的重离子辐照绝缘固体薄膜,后经化学蚀刻,在薄膜中生成纳米至微米级的穿透性微孔[1]㊂核孔膜具有表面坚实光滑㊁孔形规则㊁孔径均一等特性,在医药精密过滤㊁精细化工㊁生化分析㊁电池隔膜㊁微量探测等高端领域均有重要应用价值[2-4]㊂重离子辐照固体薄膜是核孔膜生产中的关键环节㊂国内外许多机构已开展加速器生产核孔膜的物理仿真工作[5-6],对影响核孔膜性能的加速器辐照要素进行剖析,进而优化核孔膜生产工艺㊂而针对反应堆生产核孔膜的物理仿真工作,鲜见公开发表文献㊂蒙特卡洛方法是核物理模拟的常用方法[7],本文基于蒙特卡洛程序包Geant4搭建了反应堆生产核孔膜原理性仿真平台,可物理仿真热中子辐照下靶材出射裂变碎片的种类㊁能量㊁角度等数据,及裂变碎片经准直后在固体薄膜中形成潜径迹的过程㊂利用该仿真平台,可对靶材㊁准直器㊁固体薄膜等相关参数开展物理分析及模拟计算,从而优化反应堆生产核孔膜中的物理结构设计和工艺参数㊂1㊀仿真平台设计1.1㊀几何结构模型反应堆生产核孔膜的基本流程可以概括为:热中子与靶材作用,产生裂变碎片;裂变碎片从靶材出射后经准直器准直;准直后的裂变碎片入射固体薄膜,与薄膜基材发生作用形成潜径迹;化学蚀刻潜径迹生成微孔㊂参考生产中的真实结构[8],本文构建了简化的几何结构模型,如图1所示包括中子源㊁靶件㊁准直器㊁固体薄膜四部分㊂1)中子源:反应堆堆芯核裂变产生的快中子,通过慢化技术慢化为热中子㊂本文模拟中将中子源简化为能量分布满足麦克斯韦分布的热中子,入射方向垂直于靶件所在平面㊂2)靶件:靶件为平面结构,常见的靶基材为铝㊂靶材通常为中子诱发可核裂变材料㊂裂变材料镀在200μm厚的铝基材上,镀层的厚度通常为微米量级㊂靶材的材料和厚度均可在程序中设置㊂本文模拟中,靶材材料固定为铀235丰度为90%的金属铀,厚度可调节㊂图1㊀模拟采用的几何结构模型图Fig.1㊀The geometric structure model used inthe simulation3)准直器:由于出射裂变碎片的角度分布具有随机性,生产中通常利用准直器对出射裂变碎片进行角度筛选㊂仿真平台通过设置不同的准直器结构,可对出射裂变碎片进行角度筛选,从而得到不同准直角度下出射裂变碎片的物理数据㊂本文的研究重点在于靶材裂变反应和出射过程的模拟,暂未开展准直器的优化研究工作㊂本文模拟中采用固定结构的准直器,可筛选出射角小于40ʎ的裂变碎片(出射角的定义为:碎片出射方向与靶件平面法线的夹角)㊂4)固体薄膜:常用于制备核孔膜的膜材料有聚对苯二甲酸乙二醇酸(polyethy-lene terephthalate, PET)㊁聚碳酸酯(polycarbonate,PC)等薄膜,厚度从数微米到数十微米不等㊂固体薄膜的基材材料和厚度均可在程序中设置㊂本文模拟中固体薄膜材料采用聚酯材料,化学式为C10H8O4,密度为1.40g/cm3㊂1.2㊀Geant4程序开发本文采用国际通用的成熟开源软件Geant4 (GEometry ANd Tracking4几何与跟踪程序第419第38卷第1期南华大学学报(自然科学版)2024年2月版)对上述过程进行模拟㊂Geant4是由欧洲核子研究组织(European Organization for Nuclear Re-search,简称CERN)开发的专门模拟粒子与物质相互作用的C++开源蒙特卡洛程序包[9]㊂用户可以根据需求自由更改㊁扩充程序㊂Geant4模拟的准确性已被广大科研人员所认可,被广泛的运用在高能物理㊁天文学㊁核医学㊁国土安全等领域㊂本文的模拟工作,程序运行版本为Geant4.10.06㊂1.2.1㊀粒子源设置Geant4中初级事件的生成主要是使用粒子发生器来完成㊂本文模拟使用G4ParticleGun作为粒子发生器,通过G4ParticleGun类,可以定义中子源的发射方向㊁位置㊁能量,从而模拟实际的中子源分布㊂本文模拟中将中子源简化为单一入射方向,能量分布满足麦克斯韦分布的热中子束流,最可几能量为0.0253eV㊂1.2.2㊀物理列表和环境变量设置物理列表和环境变量设置是本文仿真平台开发中的难点㊂物理过程主要描述粒子如何与物质发生相互作用㊂在本文模拟中,热中子与靶材作用发生核反应,进而生成裂变碎片是关键物理过程,为此需在程序中加入相关核裂变物理过程㊂Geant4中对物理过程和粒子的定义主要在Phys-icsList类中进行㊂本文的模拟从Geant4已有的PhysicsList中选择满足中子输运物理过程的列表,并通过相关设置激活裂变碎片的模拟㊂热中子诱发靶材裂变,需要模拟详细的中子输运过程㊂Geant4中可使用NeutronHP程序包(high precision neutron package)来模拟20MeV以下的低能中子反应㊂物理表QGSP_BIC_HP包含了NeutronHP模型,因此在主程序中将PhysicsList 设置为QGSP_BIC_HP㊂针对裂变碎片生成的模拟,B.Wendt开发了一种新的裂变事件模型,命名为裂片碎片生成器FFG(fission fragment generator)[10]㊂FFG可准确地模拟裂变事件,包括裂变碎片的质量和能量等参数㊂FFG已被集成到Geant410.0以上的版本,使用FFG需启用WENDT_FISSION_MODEL㊂裂片碎片生成的产额分布调用了G4NDL4.6/ Fission/FF中的相关截面数据,运行前需确保Geant4的数据库中已下载了G4NDL4.6库㊂由于Geant4的缺省设置里关闭了裂变碎片的生成过程,需要通过环境变量的配置来开启裂变碎片的模拟㊂在QGSP_BIC_HP物理表的基础上,将系统环境变量G4NEUTRONHP_PRODUCE_FISSION_FRAGMENTS和G4NEUTRON_HP_USE_ WENDT_FISSION_MODEL设置为YES㊂通过以上设置,仿真平台方可模拟核裂变并生成裂变碎片㊂物理过程中对反应步长的配置见下一小节㊂1.2.3㊀反应步长设置靶材和固体薄膜的厚度通常在微米量级㊂为了精确记录裂变碎片的运动轨迹,需对Geant4运行中Step的最大步长进行设置㊂设置方法为在文件中,对靶材和固体薄膜对应的逻辑体配置SetUserLimits();在主文件中,对物理列表PhysicsList调用RegisterPhysics (new G4StepLimiterPhysics())命令㊂本文的模拟中,最大步长设置为0.01μm㊂1.2.4㊀数据存储设置Geant4详细地模拟了每个事例中生成各个次级粒子输运过程中的动量㊁能量㊁时间及位置坐标信息㊂本文聚焦裂变碎片的运动径迹和能量沉积过程,在文件中,编写输出文件,将每个事例中裂变碎片Track的详细数据,写入二进制格式文件,用于后续的统计分析㊂2㊀计算结果与讨论2.1㊀初始裂变碎片的统计分析初始裂变碎片是指热中子辐照下铀235靶核发生裂变反应,生成的两个重离子碎片㊂不同厚度的铀靶,生成的初始裂变碎片在理论上具有相同的统计特性,本文以靶材厚度1μm的数据为例进行统计分析㊂图2给出了热中子辐照下铀235靶核发生核裂变,生成的初始裂变碎片按动能和质量数分布的二维散点图,图中分布呈两个明显束团㊂图2㊀裂变碎片按能量与质量数分布的二维散点图Fig.2㊀The scatter plot of fission fragmentsdistribution according to energy and mass29第38卷第1期张倩影等:基于Geant4的核孔膜生产模拟研究2024年2月图3给出了初始裂变碎片按照质量数和能量的裂变产额㊂裂变碎片的质量分布形成双峰,在幻数(A ~132)及其互补(A ~102)碎片附近的核素产额高于其他核素㊂裂变碎片动能主要分布在50~120MeV 的范围内,且明显成两个能带分布,轻碎片的动能高于重碎片的动能,服从动量守恒定律㊂每个碎片的初始动能对应约107m /s 的速度量级㊂图3㊀铀235按裂变碎片质量数的裂变产额和按能量的裂变产额Fig.3㊀The fission yield of U235as a function of product fragments mass number and product fragments energy㊀㊀以铀靶所在平面为XY 平面,铀靶的法线为Z轴,统计初始裂变碎片的出射方向㊂统计结果显示,初始碎片的出射方向为4π立体角内的均匀出射㊂2.2㊀靶材厚度的影响本文模拟中设置了不同的靶材厚度,以此探究不同靶材厚度下出射裂变碎片物理参数的变化㊂2.2.1㊀靶厚对出射强度影响中子通量一定的情况下,铀靶厚度越大,与热中子作用发生裂变的概率越大,产生的初始裂变碎片越多㊂但随着铀靶厚度的增大,裂变碎片从铀靶出射的几率随之减小㊂对不同靶材厚度,模拟计算靶核裂变概率(裂变事例与入射中子数之比)㊁表面出射概率(出射裂变碎片与裂变事例之比),绘制曲线如图4所示㊂从图4中可以看出,靶核裂变概率与靶材厚度成正比增加,表面出射概率随靶材厚度增加逐渐减小㊂定义靶核裂变概率与表面出射概率两者的乘积为出射强度系数㊂提高裂变碎片出射强度可减少辐照时间,对核孔膜的生产是有益㊂中子通量一定的情况下,裂变碎片出射强度随着靶材厚度增加而增强并逐渐达到饱和,靶材厚度为4μm 时出射强度系数达到极值,此时继续增加靶材厚度已经没有意义㊂从出射强度系数变化曲线来看,靶材厚度要控制在4μm 以下,这样既能节省靶材,又能保证较高的裂变碎片出射强度㊂图4㊀靶核裂变概率㊁表面出射概率以及出射强度系数随靶材厚度的变化曲线Fig.4㊀The variation curve of target fission probability ,surface emission probability and emission intensity coefficient with target thickness2.2.2㊀靶厚对出射能量影响如图5所示,裂变碎片在铀靶的运动径迹长度L 与核裂变发生点在靶材的深度D 和出射角θ关系为L =D cos θ(1)㊀㊀从式(1)可见,初始裂变碎片生成点在铀靶中的深度D 越大,出射角θ越大,则出射前裂变碎片在铀靶内的运动径迹L 越长,损失的能量也越39第38卷第1期南华大学学报(自然科学版)2024年2月大,导致出射裂变碎片的能量降低㊂图5㊀裂变碎片在铀靶中运动轨迹示意图Fig.5㊀The schematic diagram of the trajectory offission fragments in the Uranium target模拟计算了不同靶材厚度下,铀靶表面出射裂变碎片的能量分布情况,如图6所示㊂可见随着铀靶厚度的增加,出射能谱向低能区发生弥散㊂出射能谱的低能弥散现象,意味着出射碎片中有大量低能的粒子,这些粒子在固体薄膜内的射程很短㊂若裂变碎片不能穿透固体薄膜,会引起核孔膜中的盲孔㊂为了评估初始裂变碎片在铀靶中的深度D 和出射角θ两个因素对低能弥散现象的贡献,统计了不同靶材厚度下,裂变碎片从靶材表面出射能量与出射角度的分布散点图㊂从图7中可以看出,靶材厚度非常薄时,出射碎片的能量呈明显的两条能带㊂随着靶材厚度的增加,出射碎片的能量向低能出现弥散,且出射角度越大,弥散越严重㊂图6㊀不同靶材厚度下,裂变碎片从靶材表面出射的能谱图Fig.6㊀The energy spectrums of the emission fissionfragments from the target under differenttargetthicknesses图7㊀不同靶材厚度下,裂变碎片从靶材出射能量与出射角度的二维散点图Fig.7㊀The relationship of the energy and angle of the emission fission fragments fromthe target under different target thicknesses49第38卷第1期张倩影等:基于Geant4的核孔膜生产模拟研究2024年2月㊀㊀低能弥散受靶材厚度和出射角度两个因素叠加的影响㊂尤其是出射角度大于50ʎ时,裂变碎片在质量和能量上的分散性都很大,大量能量低的裂变碎片无法贯穿固体薄膜而形成核孔膜的盲孔㊂从这个角度考虑,为了保障核孔膜的通孔率,一方面靶材的厚度应该适当的薄,另一方面需通过准直器屏蔽出射角度过大的低能粒子㊂2.3㊀准直器的作用从图7的分布图可以看出,低能量的裂变碎片主要集中在大出射角区域㊂通过准直器筛选出射角度较小的粒子,同时选用适宜的靶材厚度,可以解决低能弥散的问题㊂准直器的代价是牺牲出射碎片的强度,对于本文模拟中采用的40ʎ准直器,靶材厚度在0.2μm 至1.0μm 区间,出射碎片强度衰减为原先的25%左右㊂不同靶材厚度下,经准直的出射碎片能谱如图8所示,可见随靶材厚度的增加,经准直后的出射碎片的平均能量和最低能量都在逐步下降㊂如靶材厚度为0.6μm 时,出射碎片的最低能量约为40MeV㊂图8㊀不同靶材厚度下,经准直的裂变碎片能谱图Fig.8㊀The energy spectrums of the collimated fissionfragments under different target thicknesses2.4㊀固体薄膜厚度的选取由于裂变碎片出射的种类㊁能量㊁方向均存在差别,导致碎片可穿透固体薄膜的最大深度存在一定的涨落㊂且裂变碎片出射能量有限,最低能量通常低于50MeV,因此生产中对固体薄膜的厚度有较为严苛的限制㊂模拟计算不同靶材厚度下,经准直器后,各裂变碎片可穿透固体薄膜最大深度d (d 为粒子径迹在固体薄膜法线方向的投影长度);然后统计d 的分布,定义概率分布函数F (T )=P {d >T }㊂以核孔膜的盲孔率为0.5%为例,计算不同靶材厚度下,F (T )=0.995时的T 值,此时的T 值即为生产核孔膜时所允许的固体薄膜最大厚度,两者关系绘制图9所示㊂图9㊀不同靶材厚度下,允许的固体薄膜最大厚度值Fig.9㊀The maximum membrane thickness underdifferent target thicknesses参考图9结果,为了确保低的盲孔率,核孔膜生产中固体薄膜的最大厚度不宜超过8μm㊂生产中建议采用0.4μm 厚的靶材,此时选用7μm 厚的固体薄膜㊂3㊀结㊀语利用反应堆产生的裂变重离子碎片辐照固体薄膜,是生产核孔膜的主要方式之一㊂在核孔膜生产过程中,裂变碎片与固体薄膜相互作用,在薄膜中形成潜径迹,是后续化学蚀刻的基础㊂本文利用Geant4搭建了反应堆生产核孔膜原理性仿真平台,可物理仿真热中子辐照下靶材出射裂变碎片的种类㊁能量㊁角度等数据,及裂变碎片经准直后在固体薄膜中形成潜径迹的过程㊂利用该平台,本文重点对靶材厚度㊁固体薄膜厚度等核孔膜生产中的相关参数开展物理分析及模拟计算,并得出了优化后的工艺参数㊂模拟结果表明,铀靶厚度为4μm 时裂变碎片出射强度最高;受裂变碎片射程的限制,反应堆生产核孔膜所用的固体薄膜(聚酯)的厚度不宜超过8μm㊂上述模拟结果与参考文献[8]的结果相吻合,证明了模拟计算的可靠性㊂核孔膜生产中可采用0.4μm 厚的靶材,40度的准直器,此时可选用7μm 厚的固体薄膜(聚酯)㊂后续工作中,以现有的原理性仿真平台为核59第38卷第1期南华大学学报(自然科学版)2024年2月心,逐步丰富靶材㊁固体薄膜等材料数据库,并开发图形化操作界面,实现模拟过程的可视化,最终完成一套反应堆生产核孔膜参数优化辅助平台㊂参考文献:[1]APEL P.Track etching technique in membrane technology [J].Radiation measurements,2001,34(1):559-566.[2]郭洪英,黄正德.离子微孔膜的研究及应用[J].核技术,2002,25(7):559-564.[3]郭士伦,张东海,王宇钢.固体核径迹研究进展[J].山西师范大学学报(自然科学版),2017,31(1): 40-49.[4]蔡畅,陈琪,苗晶,等.聚碳酸酯和聚酯核孔膜的性能研究[J].核技术,2017,40(10):26-32. [5]秦久昌,张桂莲,崔心炜,等.HI-13串列加速器核孔膜辐照专用束流线的研制[J].原子能科学技术,2000,34(6):550-552.[6]刘庆云,周剑良,刘永辉,等.纳米孔径重离子微孔膜的制备[J].原子能科学技术,2012,46(3):341-345.[7]许淑艳.蒙特卡罗方法在实验核物理中的应用[M].北京:原子能出版社,1996:20-25.[8]KOSAREV S A,TUMANOV A A.Measurement of235U fis-sion fragment range in thin lavsan films[J].Atomic energy, 2003,94(4):271-273.[9]ALLISON J,AMAKO K,APOSTOLAKIS J,et al.Recent developments in Geant4[J].Nuclear instruments and methods in physics research,section A:accelerators, spectrometers,detectors and associated equipment,2016, 835:186-225.[10]DUBROUSK I A,KIYAVITSKAYA A I.Simulation ofneutronics of an accelerator driven system[J].Physicsof particles and nuclei letters,2020,17:19-26.(上接第79页)[14]REN F,JI Y,CHEN F,et al.Flower-like bimetal Ni/Co-based metal-organic-frame work materials withadjustable components toward high performance solid-state supercapacitors[J].Materials chemistry frontiers, 2021,5(19):7333-7342.[15]LIU Y X,WANG Y Z,CHEN Y J,et al.NiCo-MOFnanosheets wrapping polypyrrole nanotubes for high-per-formance supercapacitors[J].Applied surface science, 2020,507:145089.69。

地基英文介绍

地基英文介绍Foundation, also known as footing, is an essential part of any construction project. It is the lowermost and supporting part of a structure, which transfers the weight of the building to the ground. The foundation provides stability, prevents settling, and protects the structure against moisture and other external factors.There are various types of foundations, including shallow and deep foundations. Shallow foundations are commonly used for smaller structures and are constructed close to the ground surface. They distribute the weight of the building evenly to the soil beneath. Some popular types of shallow foundations are strip foundations, raft foundations, and pad foundations.Deep foundations, on the other hand, are used when the soil near the surface cannot support the weight of the building. They need to reach deeper and rely on the stronger soil layers underneath. Pile foundations and caisson foundations are two examples of deep foundations. Pile foundations are made up of long, slender piles that are driven deep into the ground. Caisson foundations are large, hollow structures that are sunk into the ground and filled with concrete.The process of building a foundation involves several steps. First, the area is cleared of any vegetation or debris. Then, the soil is excavated to the required depth and compacted to ensure stability. Next, formwork is put in place to shape the foundation. Reinforcement bars are added, and concrete is poured into the formwork. The concrete is then cured and allowed to harden, forming a solid base for the structure.In addition to providing stability, the foundation also plays a crucial role in insulation and waterproofing. Special attention is given to ensuring that the foundation is properly insulated to prevent heat loss and maintain a comfortable indoor temperature. Waterproofing techniques are also applied to protect against water infiltration and moisture damage.Overall, the foundation is a critical component of any construction project. It provides a solid base for the structure, ensures stability, and protects against various environmental factors. A well-designed and properly constructed foundation is essential for the long-term durability and safety of any building.。

Lecture_4

© 2000 Richard P. Muller
11
Adding to parent functions
• Sometimes you want to extend, rather than replace, the parent functions.
class qm_molecule(molecule): def __init__(self,name="Generic",basis="6-31G**"): self.basis = basis molecule.__init__(self,name)
© 2000 Richard P. Muller
9
Inheritance
class qm_molecule(molecule): def addbasis(self): self.basis = [] for atom in self.atomlist: self.basis = add_bf(atom,self.basis)
class qm_molecule(molecule): def __repr__(self): str = 'QM Rules!\n' for atom in self.atomlist: str = str + `atom` + '\n' return str
• Now we only inherit __init__ and addatom from the parent • We define a new version of __repr__ specially for QM
• __init__, __repr__, and __addatom__ are taken from the parent class (molecule) • Added a new function addbasis() to add a basis set • Another example of code reuse

建筑结构英文单词

建筑结构英文单词Building Structure。

Introduction:Building structure refers to the arrangement and integration of various components that provide stability and support to a building. It is a crucial aspect of architectural design, ensuring the safety and durability of the structure. This article will explore the key elements and concepts related to building structure, including foundation, load-bearing walls, beams, columns, and roof systems.Foundation:The foundation is the base of a building structure, transferring the load from the superstructure to the ground. It is typically constructed using concrete or masonry and is designed to distribute the load evenly. Common types of foundations include shallow foundations, such as strip foundations and raft foundations, and deep foundations, such as pile foundations and caissons. The choice of foundation depends on factors like soil conditions, building loads, and local regulations.Load-Bearing Walls:Load-bearing walls are an essential part of the building structure, responsible for carrying the vertical loads from the floors and roof down to the foundation. These walls are designed to resist compression forces and provide stability to the structure. Load-bearing walls are typically made of materials like concrete, masonry, or steel. In modern construction, load-bearing walls are often combined with non-load-bearing walls to create an efficient and flexible floor plan.Beams:Beams are horizontal structural members that support the weight of the structure above and transfer it to the load-bearing walls or columns. They are designed to resist bending and shear forces. Beams can be made of various materials, including wood, steel,and reinforced concrete. The choice of beam material depends on factors like span length, load requirements, and architectural preferences. Different types of beams, such as simply supported beams, cantilever beams, and continuous beams, are used based on the structural needs.Columns:Columns are vertical structural elements that provide support to the beams and transfer the load to the foundation. They are designed to resist compression forces and maintain the stability of the structure. Columns can be made of materials like concrete, steel, or composite materials. The shape and size of columns vary depending on the architectural design and load requirements. Common column shapes include rectangular, circular, and square.Roof Systems:The roof system is an integral part of the building structure, protecting the interior from weather elements and providing structural support. Different types of roof systems are used based on the architectural style, climate conditions, and construction materials. Common roof systems include flat roofs, pitched roofs, and arched roofs. The roof structure consists of elements like roof trusses, purlins, and sheathing, which work together to distribute the load evenly and provide stability.Conclusion:Building structure plays a vital role in ensuring the safety, durability, and functionality of a building. It involves the integration of various components, including foundation, load-bearing walls, beams, columns, and roof systems. Each element is carefully designed and constructed to withstand the loads and forces acting on the structure. By understanding the key concepts and principles of building structure, architects and engineers can create aesthetically pleasing and structurally sound buildings.。

地铁地基承载力数值

地铁地基承载力数值英文回答：Subway Foundation Bearing Capacity Values.The bearing capacity of a subway foundation is acritical factor in ensuring the safety and stability of the structure. It is the maximum load that the foundation can support without failing. The bearing capacity is determined by a number of factors, including the soil conditions, the depth of the foundation, and the type of foundation.Soil Conditions.The soil conditions at the site of the subway foundation are a major factor in determining the bearing capacity. The type of soil, its density, and its moisture content all affect the bearing capacity. Soft, loose soils have a lower bearing capacity than hard, dense soils. Wet soils also have a lower bearing capacity than dry soils.Depth of the Foundation.The depth of the foundation is another factor that affects the bearing capacity. The deeper the foundation,the greater the bearing capacity. This is because the soilat greater depths is typically more compacted and lesslikely to fail.Type of Foundation.The type of foundation also affects the bearing capacity. There are a number of different types of foundations, each with its own advantages and disadvantages. The most common type of foundation for subways is thespread footing. Spread footings are wide, shallow foundations that spread the load of the structure over a large area. Other types of foundations include pile foundations and caisson foundations.Bearing Capacity Values.The bearing capacity values for subway foundations vary depending on the soil conditions, the depth of the foundation, and the type of foundation. However, typical bearing capacity values for subway foundations range from 100 to 500 kPa.中文回答：地铁地基承载力数值。

大学土木工程英语教材

大学土木工程英语教材Chapter 1: Introduction to Civil EngineeringCivil engineering is a branch of engineering that deals with the design, construction, and maintenance of infrastructure such as roads, bridges, buildings, and dams. In this chapter, we will provide an overview of the field and its various sub-disciplines.1.1 Definition and Scope of Civil EngineeringCivil engineering encompasses a broad range of activities aimed at improving the built environment. It involves the planning, design, construction, and management of infrastructure projects. The scope of civil engineering includes structural engineering, geotechnical engineering, transportation engineering, water resources engineering, and environmental engineering.1.2 Historical DevelopmentsCivil engineering has a rich history that dates back to ancient civilizations. The construction of monumental structures such as the great pyramids of Egypt and the Roman aqueducts demonstrated early engineering achievements. Over time, civil engineering has evolved and adapted to meet the changing needs of society.1.3 Roles and Responsibilities of Civil EngineersCivil engineers play a crucial role in society by ensuring the safety, functionality, and sustainability of infrastructure projects. Their responsibilities include conducting feasibility studies, preparing design plans,managing construction sites, and overseeing the maintenance and inspection of structures.Chapter 2: Fundamentals of Structural EngineeringStructural engineering is a major sub-discipline of civil engineering that focuses on the design and analysis of structures. This chapter will introduce the basic principles and concepts in structural engineering.2.1 Load AnalysisThe first step in structural design is to determine the loads that a structure will be subjected to. These loads can be classified into dead loads, live loads, wind loads, and seismic loads. Understanding the magnitude and distribution of these loads is essential for ensuring the structural integrity of a building.2.2 Structural MaterialsStructural engineers must select appropriate materials for construction based on their properties and performance. Common structural materials include concrete, steel, timber, and masonry. Each material has unique characteristics that influence its suitability for different applications.2.3 Structural SystemsStructural systems refer to the arrangement and configuration of structural elements within a building. Examples of structural systems include frames, arches, shells, and trusses. The choice of system depends on factors such as span, function, and aesthetics.Chapter 3: Geotechnical EngineeringGeotechnical engineering deals with the behavior and properties of soil and rock materials. This chapter will cover the fundamentals of soil mechanics and its applications in civil engineering.3.1 Soil PropertiesUnderstanding soil properties is essential for designing foundations, slopes, and earthworks. Soil properties such as grain size, moisture content, and compaction characteristics affect the stability and bearing capacity of structures. Various laboratory and field tests are conducted to determine these properties.3.2 Soil StabilizationIn some cases, soil may be unstable or unsuitable for construction. Geotechnical engineers employ various techniques to improve soil properties, including compaction, soil reinforcement, and grouting. These methods increase soil strength and stability.3.3 Foundation DesignFoundations are critical for transmitting loads from a structure to the underlying soil. Geotechnical engineers design foundations based on soil conditions, structural requirements, and local regulations. Common types of foundations include shallow foundations, deep foundations, and pile foundations.Chapter 4: Transportation EngineeringTransportation engineering involves the planning, design, and operation of transportation systems. This chapter will explore the different modes of transportation, traffic flow theory, and highway design principles.4.1 Modes of TransportationTransportation systems comprise various modes, such as roads, railways, airports, and waterways. Each mode has its own characteristics and considerations. Transportation engineers analyze traffic patterns and design infrastructure to optimize the flow of people and goods.4.2 Traffic Flow TheoryUnderstanding traffic flow is essential for designing efficient transportation networks. Traffic engineers study factors such as traffic volume, speed, and density to model and predict traffic behavior. This knowledge helps in designing intersections, signal timing, and capacity analysis.4.3 Highway DesignHighway design involves the layout and geometric design of roads and highways. Engineers consider factors such as road alignment, sight distance, cross-sectional elements, and pavement design. These considerations ensure safe and efficient movement of vehicles.Chapter 5: Water Resources EngineeringWater resources engineering focuses on the management and utilization of water resources. This chapter will cover topics such as hydrology, water supply systems, and hydraulic structures.5.1 HydrologyHydrology deals with the study of water in the environment, including rainfall, runoff, and water storage. Hydrological analysis helps in predicting floods, estimating water availability, and designing drainage systems. Engineers use mathematical models and data analysis techniques to understand and manage water resources.5.2 Water Supply SystemsWater supply systems involve the collection, treatment, and distribution of water for domestic, commercial, and industrial purposes. Engineers design infrastructure such as dams, reservoirs, water treatment plants, and distribution networks to ensure a reliable water supply.5.3 Hydraulic StructuresHydraulic structures are designed to control water flow and manage water resources. Examples include dams, canals, weirs, and flood control channels. Engineers consider factors such as flow rates, sediment transport, and environmental impacts when designing these structures.ConclusionThis English textbook for college-level civil engineering students provides a comprehensive introduction to the field. From the basics of civil engineering to specialized topics such as structural engineering, geotechnical engineering, transportation engineering, and water resources engineering, students will gain a solid foundation in the discipline. With its clear explanations and well-organized content, this textbook is an invaluable resource for aspiring civil engineers.。

斜截面剪切破坏 (自动保存的)

名词解释：Foundation：基础是将建筑物承受的各种荷载传递到地基上的实体结构。

Shallow foundation：浅基础一般指基础埋深小于5m，或者基础埋深小于基础宽度的基础。

Spread footing：将上部结构传来的荷载，通过向侧边扩展成一定底面积，使作用在基地的压应力等于或小于地基土的承载力特征值，面基础内部应力同时满足材料本身的强度要求，这种起到压力扩散作用的基础叫扩展基础。

Mats：当建筑物上部荷载较大而地基承载能力又比较弱时，用简单的独立基础或条形基础已不能适应地基变形的需要，这时常将墙或柱下基础连成一片，使整个建筑物的荷载承受在一块整板上，这种满堂式的板式基础称筏形基础Deep foundation：一般指基础埋深大于基础宽度且深度超过5m的基础，深基础是埋深较大，以下部坚实土层或岩层作为持力层的基础Piles：桩基础由基桩和联接于桩顶的承台共同组成。

若桩身全部埋于土中，承台底面与土体接触，则称为低承台桩基；若桩身上部露出地面而承台底位于地面以上，则称为高承台桩基。

floating foundation：【浮式基础】带有一定地下空间的基础，通过减少土的量使基底净压力为零或尽可能小，则基础沉降就很小或为零，就像基础“浮”在基础下面的土体上。

Compensation foundation：补偿基础是用以减少由建筑物荷载引起的地基沉降，而以岩土自重大致相当于建筑荷载的原则而砌筑于地下相应深度处的整体性基础置换效应：基础置换了原有的土，使得土体的性质改变。

Two-way(one-way)tension reinforcing:设置受拉钢筋的扩展基础可按抗弯钢筋是沿两个方向还是一个方向设置而分别被称为双向或单向基础Single footing/ Isolate footing:当建筑物上部结构采用框架结构或单层排架结构承重时，基础常采用方形、圆柱形和多边形等形式的独立式基础，这类基础称为独立式基础Wall footing：基础长度远远大于宽度的一种基础形式Rigid footing：基础底部扩展部分不超过基础材料刚性角的天然地基基础·受刚性角限制的基础称为刚性基础Eccentrically loaded spread footing：受到偏心荷载的扩展基础Wide beam action：基础上宽梁上剪力控制基础厚度Two—way action：双向剪切破坏【冲剪破坏】Reinforced concrete footing：钢筋混凝土基础~由钢筋混凝土制成的基础Flexible footing：柔性基础是指用抗拉、抗压、抗弯、抗剪均较好的钢筋混凝土材料做基础Spread footing without the reinforceincat：无筋扩展基础是基础的一种做法，指由砖、毛石、混凝土或毛石混凝土、灰土和三合土等材料组成的，且不需配置钢筋的墙下条形基础或柱下独立基础。

土力学(中英文对照)-- 8 Bearing Capacity Part

foundation, o is unit weight of soil above the base of the
foundation
N'
cot
2
Nc
cot cot
2
Nq
1
cot
2
8.4 Allowable bearing capacity of shallow foundations
(当M点达到极限平衡状态时,大小主应力必需满足以
下公式)
1
3
tan2 45
2
2c
tan 45
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▪ z is depth of the plastic zone and is expressed as a function of b (z为塑性区深度,是b的函数)
z
q
d
sin2b sin
surface of a homogeneous and isotropic soil. In addition, an additional surcharge pressure qo acts on the soil surface (下图代表一条形基础:基础宽度为b,无限长度,均布荷载q, 地基为均质土和各性同向,基础两侧均布荷载为qo)
to the principal stresses. The final principal stresses at depth z are (假设静止土压力糸数Ko=1,这样自重应力与附加应力可以在任意方向叠加,地基中任意点M的大小主应力可从以下公式找出 )
1
q
d
2b
sin2b
z
d
3
q
d
2b
▪ If zmax is chosen as b/3