断层宽度对跨断层隧道错动反应特性影响的数值模拟_林克昌

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断层错动对上覆土体及隧道影响的模型试验

在隧道纵向位置及应变值进行比较，分析其对隧道变形的影响，
具体情况见表１。
表１应变极值点位置对比
垂直错距
一４ｍｍ０一３ｍｉ５ｌｌ３ｌ０ｍｉｌ一２５ｍｍ・２ｍ０ｎＩ１ｔ５ｍｍ．＋ｌｍｉ０ｌｌ
则较小。
隧道纵向位置／ｅｍ
０１２３４５６７８９００Ｏ０００００００１０ｌｏ００Ｏ
一
咖㈣咖ｏ
跏咖咖。跏姗咖
将隧道距基岩面距离不同时，隧道顶部及底部的应变极值点
４
形出现反弯点。４断层错动过程中，）隧道纵向位置位于错动迹线末端一小部分区域处于受拉状态。此外，各测点应变的绝对值随
表左侧部分受影响较大，变值也比较大，应而位于其右侧的应变值错距的增加而增大，明错距越大对隧道影响越大。
— 。
１Ｏｏｏ
∞
－
Ｉ－
４０００５０００
６０ｏｏ７０００
；
ａ隧道顶部）
’ 一 —
隧道顶部
隧道距基岩面距离应变极值点错动迹线纵向位置Ｃｍ测点纵向位置／ｍ应变／．ｃＤｓＣｌｉＴ
一
１模型试验设计
１１砂箱模型设计．
本试验采用的模型箱的尺寸大小为长１２０ｍ宽６０ｍ０ｍ，０ｍ，
底部的纵向应变。本次选用波长范围为１５３ｎ２ｍ～１６ｍ，３ｎ采５用ＭＩＯ光纤光栅传感解调仪进行数据采集。

2023年公路隧道超前地质预报技术规程标准DB45T 2525—2022

公路隧道超前地质预报技术规程1范围本文件规定了公路隧道超前地质预报的术语和定义、一般规定、超前地质预报设计、超前地质预报实施、地质调查法、物探法、超前钻探法、超前导坑法和复杂地质条件的超前地质预报。

本文件适用于公路隧道超前地质预报工作，其它地下工程的超前地质预报可参照使用。

2规范性引用文件本文件没有规范性引用文件。

3术语和定义下列术语和定义适用于本文件。

隧道超前地质预报geological predication in tunnel在分析既有地质资料的基础上，采用地质调查、物探、超前地质钻探、超前导坑等手段，对隧道开挖工作面前方的工程地质与水文地质条件及不良地质体的工程性质、位置、产状、规模等进行探测及分析判释，并提出技术措施建议。

综合超前地质预报comprehensive geological prediction根据预报对象的地质特点，采取两种或两种以上有效的预报手段进行相互比较印证的超前地质预报方法。

地质复杂程度分级classification of geological factors by intricacy综合考虑隧道工程地质与水文地质条件、可能发生的地质灾害对隧道施工及环境的影响程度，对隧道所处地质条件复杂程度进行的分级，包括复杂、较复杂、中等复杂和简单四级，对应着隧道地质灾害分级的：严重、较严重、一般、轻微。

地质调查法geological survey method根据隧道已有勘察资料、地表补充地质调查资料和隧道内地质素描，通过地层层序对比、地层分界线及构造线地下和地表相关性分析、断层要素与隧道几何参数的相关性分析、临近隧道内不良地质体的前兆分析等，利用常规地质理论、地质作图和趋势分析等，推测开挖工作面前方可能揭示地质情况的一种超前地质预报方法。

包括隧道地表补充地质调查和隧道内地质素描等。

隧道内地质素描geological sketch of the inside of tunnel将隧道所揭露的地层岩性、地质构造、结构面产状、地下水出露点位置及出水状态、出水量、煤层、溶洞等准确记录下来并绘制成图表的一种超前地质预报方法。

中国地质构造学研究历史

地洼学说认为，在地壳演化史上，不只活动区可以转化为“稳定” 区，而“稳定”区也可转化为新的活动区。大陆地壳的发展过程，并非如地槽—地台说认为的那样，直线地仅由地槽阶段发展到地台阶段，而是多阶段、螺旋式的升进。通过活动区与“稳定”区之间的互相转化递叠，按照“否定之否定”法则向前发展，这叫 “动、定转化递进律”。它的力源机制在于上地幔软流层的物质运动，叫散聚交替光在研究中国和东亚构造的基础上于20世纪40年代创立的一种构造地质学说。它主要是用力学的观点研究地质构造现象，研究地壳各部分构造形变的分布及其发生、发展过程，用来揭示不同构造形变间的内在联系。地质力学注重构造体系的分析，特别是活动构造的活动规律和动力来源，以及断层、褶皱等构造形迹形成的力学机理的分析，也注重研究地应力和地质因素对岩土工程的力学分析的影响，地质力学对矿产资源的普查勘探、对工程地质和地震地质的研究有积极意义。
地质界传统的理论是大陆地壳大发展过程只有两个阶段：先出现活动区—地槽区，后来变为“稳定” 区—地台区。1956年，陈国达在总结中外地质资料的基础上提出，中生代中期以来地壳演化进入了新阶段，经受断裂作用和拱曲作用后所形成的狭长形或长圆形的凹地或凸起，其大地构造性质既非地台区，也与地槽区有别，而是一种新型活动区，是大陆地壳的第三构造单元。因它是地台区向活动区转化的产物，故取名为活化区；又因其最主要的特征是区内出现地洼盆地，故称地洼区。
地质力学既研究地壳运动产生的各种形变现象的规律，也研究由地壳运动产生的物质的变化规律，以及两者的相互联系。反映地壳运动的一切现象都是它考察研究的对象，包括构造体系的规律、海洋运动的遗迹、岩浆活动的现象、变质岩带的发生和矿产的形成等。
地质力学的研究内容可概括为四个方面： 1、构造体系的深入调查研究； 2、全球大地构造体系的特点和分布规律，以及与各种构

走滑断层地震地表变形与破裂宽度数值分析

173走滑断层地震地表变形与破裂宽度数值分析李红1,2）邓志辉3）陈连旺4）周庆1）冉洪流1）邢成起2）1）中国地震局地质研究所，北京 1000292）北京市地震局，北京 1000803）广东省地震局，广州 5100704）中国地震局地壳应力研究所，北京 100085震后野外考察表明，走滑断层同震引起的地表变形主要集中在断层两侧很窄的范围，为定量研究同震地表强变形分布特征与破裂带宽度，以鲜水河断裂北西段为原型设计了一个简化的三维黏弹有限元模型，断层遵从库仑滑动定律，断层长度20 km ，走向320°，厚度11 km ，两侧各宽3 km 。

由已知地震断层面的突然错动在地表引起的位移分布，求出任意相邻两点之间的位移量差值，即变形量，它是依赖于两点间距离的变量。

对于空间相邻两点d i 和d i+1，其水平位移差h i 为h i +1－h i ；垂向位移差为Z i +1－Z i 。

总位移差d i由j d Δd i 空间位置位于相邻两点d i 和d i +1的中间，可以表示为：1(+)/2j i i d d d +Δ=。

以断层相对左旋位错模拟强震（如1973年炉霍M S 7.6地震的最大地表水平位错为3.6 m ），模型南西与北东边界在垂直断层走向方向约束，平行断层走向方向自由，底面垂向约束。

取地表上自南西盘向北东盘经过断层长度中点（假定为强震震中投影）O ，垂直于断层走向的AB 测线（AO 、BO 均为100 m ，沿AB 单元尺度为2 m ，网格为六面体）的地表变形数据，以每米0.02 m 的地表变形量为破裂阈值，即2 m 跨度变形量超过0.04 m 时认为可导致地表破裂，换算出宽度。

结果如下。

（1）不同位错量（1.5～8.5 m ，增量约为0.5 m ，断层倾向北东，倾角80°）：①AB 测线的变形量曲线为约以断层为中心的对称单峰型，强变形主要集中在断层两侧各50 m 范围内，达到破裂阈值的破裂宽度更窄。

1 项目类别直接费用开始日期结题日期

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中南祁连西缘肃北逆冲断层起始 23 师文贝活动时间：中-低温热年代学制 D0305 青年科学基金项目 24 2020-1-1 2022-12-31
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65 2020-1-1 2023-12-31 65 2020-1-1 2023-12-31 65 2020-1-1 2023-12-31 65 2020-1-1 2023-12-31 67 2020-1-1 2023-12-31 60 2020-1-1 2023-12-31 60 2020-1-1 2023-12-31 62 2020-1-1 2023-12-31 64 2020-1-1 2023-12-31 63 2020-1-1 2023-12-31 64 2020-1-1 2023-12-31 63 2020-1-1 2023-12-31 64 2020-1-1 2023-12-31

Experimental study on normal fault rupture propagation in loose strata

Experimental study on normal fault rupture propagation in loose strata and its impact on mountaintunnelsXuezeng Liu a ,⇑,Xuefeng Li b ,Yunlong Sang c ,Lianglun Lin daCollege of Surveying and Geo-Informatics,Tongji University,Shanghai 200092,China bCollege of Civil Engineering,Tongji University,Shanghai 200092,China cShanghai Tong Yan Civil Engineering Ltd.,Shanghai 200092,China dChongqing Construction Science Research Institute,Chongqing 400015,Chinaa r t i c l e i n f o Article history:Received 13March 2014Received in revised form 20April 2015Accepted 24May 2015Available online 16June 2015Keywords:Normal fault Rupture Propagation TunnelExperimental studya b s t r a c tUnderstanding earthquake fault rupture propagation is important in building and lifeline engineering,especially in the construction of mountain tunnels.Thus,studying rupture propagation in strata and tun-nel failure with fault displacement is signiﬁcant.For this purpose,an experiment has been designed to simulate normal fault displacements with different dip angles.The inﬂuence of normal faults on tunnels has been observed by examining the rupture and strata deformation and analyzing the shear zone,tunnel stain,position,and forms of tunnel cracks.The results show that more than one strata rupture appears when the normal fault moves,and at least one rupture reaches the ground surface as the vertical fault dislocation is approximately 4.4%of the covering depth.In general,those ruptures form an inverted tri-angle zone in which strata deform signiﬁcantly.The range of the rupture shear zone increases as the fault dip angle decreases.Strata-tunnel -fault can be considered as a beam on an elastic foundation.The lining of the tunnel in the hanging wall and shear zones is subjected to sagging,and that in the foot wall zone is subjected to hogging.Failure modes appear to change with fault dip angle.The lining damage form is ﬂexure failure occurring mainly in the foot wall with the circumferential cracks,when the dip angle is 75°.When the dip angle is 60°and 45°,the failures are caused by a combination of ﬂexure and shear both in the shear and foot wall zones with a lot of circumferential and diagonal cracks.Furthermore,to guide design work reasonably,the calculation method in determining the weak parts of the tunnel and feasible reinforcement measures are discussed.Ó2015Published by Elsevier Ltd.1.IntroductionTectonic earthquakes have two main failure modes:strata vibrations triggered by seismic waves and permanent strata defor-mations caused by fault dislocation.The permanent deformations of strata have a signiﬁcant effect on buildings and lifeline engineer-ing because of differential movements on both sides of the faults,especially on linear structures such as underground pipelines and tunnels.The optimal solution is to select a proper site and avoid any potential fault structure.However,this solution is impractical because of the extension and width of tunnels (Lee and Hamada,2005).For example,several tunnels of the Duwen highway near the earthquake fault zone were damaged during the Wenchuan earthquake.All the main bodies of 13tunnels through adverse geo-logical structures were seriously damaged,and some even col-lapsed.The vertical displacement and the dextral horizontal displacement reach are 5.0m and 4.8m,respectively,in the rupture zone of the Longmen Mountain,and the average disloca-tion reaches 23m (Zhang et al.,2008)along the rupture zone.Understanding failure modes is crucial in designing tunnels in failure-prone locations.Many scholars have studied propagations of active faults in bedrock overburdens.Scale model tests and centrifuge tests have been conducted using sand and clay samples (Bray et al.,1994a;Guo et al.,2001;Johansson and Konagai,2007;Lin et al.,2006;Liu and Hamada,2004;Roth et al.,1981).Propagations and geo-metric characteristics of ruptures have been identiﬁed.Numerical studies on strain ﬁeld and plastic deformation caused by rupture propagations in severely deformed regions have been reported and compared with scale model experiments (Bray et al.,1994b;Johansson and Konagai,2007;Lin et al.,2007).The effects of fault dip,formation material properties,overburden thickness,and dis-placement on the rupture propagation have been discussed as well.Shear displacement caused by fault bedrock dislocation can propagate through the cover layer to the ground surface.Rupture propagation creates a severely deformed region in the bedrock/10.1016/j.tust.2015.05.0100886-7798/Ó2015Published by Elsevier Ltd.Corresponding author.cover layer and extends upward as bedrock displacement develops. More than one rupture(Lee and Hamada,2005)can be formed through normal fault rupture propagation in general.Likewise, when the displacement of the reverse fault is large enough,a sec-ondary rupture(Taniyama and Watanabe,2002)can occur outside the primary sliding surface.Taniyama found that the rupture sur-face propagated through the alluvium if the vertical bedrock fault displacement reached3–7%of the depth of the alluvium.Burridge et al.(1989)conducted a series of scaled model exper-iments in a centrifuge to assess the effect of fault rupture move-ment on tunnels.Based on experimental results,a model was developed and used to calculate the vertical displacement,longitu-dinal bending moment,and shearing force of the inﬁnitely long prototype tunnel under fault displacement of0.61m and1.12m, respectively.Johansson and Konagai(2007)used model test and numerical simulation to determine the structural design criteria based on fault displacement and failure strain.Field observations and numerical simulation results showed that the surrounding horizontal stress of the underground structures should be consid-ered in the design.Lin et al.(2007)studied the deformation and the stability of strata and tunnels under different control factors using sand box experiment and numerical simulation for reverse faults with large dislocation distance.The inﬂuence of tunnel structure on the rupture propagation was also investigated based on observation data.To date,neither physical modeling nor its effect on mountain tunnels has been performed to investigate the rupture propagation in loose strata.However,this study should be important because fault structures are unavoidable in building tunnels.A clear under-standing of the stress and deformation mechanism of tunnel cross-ing fault is necessary.This paper presents an experimental study that focuses on the The sand box is composed of8mm thick steel plates.The bottom plate of the box is composed of a hanging wall(movable)and a foot wall(ﬁxed)based on normal faults.A photograph of the test appa-ratus is shown in Fig.2.The hanging wall can be moved up or down to simulate the fault displacement,which is achieved by manipu-lating the oil jack underneath the sand box.The bearing is arranged between the loading system and hanging wall bottom plate so that the fault dip angle can vary between30°and90°.During site observation,the normal fault dip is relatively large.Therefore,in our test,the fault dip-angles are75°,60°,and45°,respectively. During the test,a digital camera is mounted on one side of the model box to record the rupture propagation.In the test,a prescribed displacement is applied at the bottom to simulate the fault dislocation.The bottom plate of the box sim-ulates the fault bedrock,whereas the sand soil simulates the loose cover layer.The simulated tunnel is buried at a designated distance above the bedrock.The ruptures induced by the displacement of bedrock propagate upward in the cover layer,which simulates the mechanism of fault dislocation.When the bottom plate on the hanging wall side is moved down,an obvious rupture occurs in the overlay.The loading procedure is conducted as follows.Given the afore-mentioned displacement of the Longmen Mountain rupture zone, the hanging wall is raised by10cm(D H=100mm)prior to the experiment.The model box isﬁlled with multiple layers of sand with10cm height intervals,and white powder isﬁlled between layers as markers.The thickness of the sand is90cm for the ele-vated hanging wall and100cm for the foot wall.A lifting height of D H=100mm is used in the scaling experiment,which corre-sponds to the maximum vertical displacement of the prototype of5m.In fact,a vertical displacement of several meters did occur during the earthquakes in Chi-Chi,Taiwan(Wang et al.,2000)andFig.1.Schematic of the test apparatus.Fig.2.Photograph of the test apparatus(original state). 418X.Liu et al./Tunnelling and Underground Space Technology49(2015)417–4254.Dip angle=75°.(a)Final state of rupture for normal fault.(b)Schematic rupture for normal fault.(c)Schematic of rupture propagation for normal fault.Rupture propagation proceeds as follows:when the vertical dis-placement of the hanging wall reaches10mm,rupture1appears near the path line of the normal fault with a height of20cm. When the vertical displacement reaches40mm,rupture1reaches the ground surface quickly.Rupture2initiates when the vertical displacement reaches30mm and reaches the surface ground when the vertical displacement is80mm.Fig.4(c)shows the rupture propagation height versus different vertical displacements for both ruptures.Comparatively,more ruptures emerge in the60°fault test,as shown in Fig.5(a)and(b).All ruptures extend up to ground surface except for rupture3.The rupture propagation range is wider than that in the75°fault test.Fig.5(c)shows the fault propagation process.When the vertical displacement reaches10mm,the height of rupture1is30cm;as the vertical displacement reaches 100mm,rupture1arrives at the ground surface.Rupture4initi-ates when the vertical displacement reaches10mm.When the vertical displacement is30mm,rupture4reaches the ground sur-face and forks out to form rupture5.Ruptures4and5coincide near the ground surface.The45°dip angle fault test is shown in Fig.6(a)and(b).Six rup-tures are formed in total;only rupture5does not extend up to the ground surface.The rupture propagation range is wider than those in the75°and60°fault tests.Fig.6(c)shows the fault propagationFig.5.Dip angle=60°.(a)Final state of rupture for normal fault.(b)Schematicrupture for normal fault.(c)Schematic of rupture propagation for normal fault.Fig.6.Dip angle=45°.(a)Final state of rupture for normal fault.(b)Schematicrupture for normal fault.(c)Schematic of rupture propagation for normal fault.In general,as the normal fault moves downward slightly,rup-tures appear and propagate upward approximately parallel to thepath line of the fault,intending to bifurcate near the fault tip andﬁnally reach the ground surface.Rupture propagation paths differmarkedly from the supposed fault line as vertical displacementincreases.As the vertical displacement of fault equals4.4%of thecovering thickness regardless of dip angle,approximately2.0mfor the full-scale prototype(distance from the bedrock to theground surface),at least one rupture reaches the ground surface.Then,most extend up to the ground surface.Only a few rupturesstop halfway as the fault vertical displacement reaches11.1%ofcovering thickness.Those bifurcated ruptures compose an invertedtriangular region often called a‘‘shear zone.’’3.2.Geometric features of rupture shear zoneLongitudinal strain versus fault vertical displacement with a dip angle a=75°.(a)Tunnel arch,(b)tunnel bottom and(c)schematic of longitudinalX.Liu et al./Tunnelling and Underground Space Technology49(2015)417–425421zone equally in angle);a M is similar between the three dip angles. The model tunnel intersects with the shear zone.The intersected segment length L of fault dip75°,60°,and45°are8,26,and 41.5cm,respectively;L increases as the fault dip angle decreases. The distance of the rupture on the ground surface on the left and right is W.It also increases as the fault dip decreases.These param-eters are summarized in Table1.The summarized data show that the length L and W have linear relationships with the dip angle of the fault,which is L=À1.12a+92and W=2.17a+179,as shown in Fig.7and Table1.Thus,for any tunnel constructed under similar conditions, if the position of the normal fault tip is known,designers can deter-mine the range of shear zones reasonably and clearly,and then consider these factors in structural reinforcement.4.Analysis of tunnel mechanical features and failure modes 4.1.Longitudinal strainsFigs.8–10show curves of lining longitudinal strain variation with vertical fault displacement.A positive strain represents ten-sile strain and a negative strain represents compressive strain. The following paragraphs describe strains for the three cases.75°dip angle:When the fault vertical displacement distance is small,the strain increases rapidly.When the vertical displacement reaches40mm,the strain of each gauging point tends to stabilize. The maximum tensile and compressive strains in vault are located in small regions between the two fault ruptures.In this case,they occur at Sections#5and#3with values of1300EÀ6and À1422EÀ6,respectively.The initial tensile strain on#4is small; when the fault dislocation distance reaches30mm,it changes to compressive strain.At the bottom,the maximum tensile is 200EÀ6at Section#2;the maximum compressive strain is À900EÀ6,which occurs at Section#5.The initial compressive strain occurs at the bottom of#3is small.When the dislocation reaches20mm,it is converted into tensile strain and remains small.Strain data in Fig.10show that when the fault vertical dis-placement reaches30mm,tensile strain in vault Section#5is extremely large and tensile failure occurs.The compressive strain data are all small and no compression failure occurs.Inﬂection point is0.5D,far to the right of the main rupture path,as shown in Fig.8.60°dip angle:When the fault vertical displacement reaches 40mm,the strain gauge on the tunnel vault of#5and#2fails because of the tension.The maximum tensile and compressive strains are distributed in the foot wall zone of the tunnel,speciﬁ-cally in#5and#3with values of1911EÀ6andÀ4262EÀ6,respec-tively.At the tunnel bottom,the maximum compressive and tensile strains occur in#2and#5with values of2433EÀ6and À4458EÀ6,respectively.Strains at the bottom of#3remain within a small range.Data in Fig.11shows that tensile strains in the vault of Sections#5and#6and at the bottom of Section#2are very large,and tensile failure pressive strains in the vault of#3and at the bottom of Section#5are very large. Compression failure occurs.The inﬂection point is0.65D far to the right of the main rupture path,as shown in Fig.9.45°dip angle:When the fault vertical displacement exceeds 30mm,the strain gauges on the tunnel vault of#5and at the bot-tom of#2fail because of high tension.The maximum tensile and compressive strains are distributed in the shear zone and the foot wall zone of the tunnel,speciﬁcally in#5and#2,and the values are2187EÀ6andÀ3763EÀ6,respectively.The tunnel vault strain in#4always remains within a small range.The maximum tensile and compressive strains occur in#2and#4at the tunnel bottom with1512EÀ6andÀ3707EÀ6,respectively.Strains at the bottom of#3remain within a small range.Data in Fig.12show thattensile Longitudinal strain versus fault vertical displacement with a dip angle a=60°.(a)Tunnel arch,(b)tunnel bottom and(c)schematic of longitudinalstrains in the vault of Sections#5and#6and at the bottom of Section#2are very large.Tensile failure pressive strains in the vault of#2and at the bottom of Sections#4and #5are very pression failure occurs.The inﬂection point is1.5D,far to the right of the main rupture path,as shown in Fig.10.Generally,the longitudinal bending moment in the hanging wall shear zones is subjected to sagging.That in the foot wall zoneLongitudinal strain versus fault vertical displacement with a dip angle a=45°.(a)Tunnel arch,(b)tunnel bottom and(c)schematic of longitudinalHoop strain varies of fault vertical displacement with dip angle a=75°.(a)Section#1,(b)Section#2,(c)Section#3,(d)Section#4,(e)Section#5and(f)Sectionis subjected to pressive strains are slightly larger than tensile strains.The tunnel is under unsymmetrical compression.Results show that the main failure cracks of the tunnel are caused by tensile stresses.Tensile zones are shown in Figs.8–10. Given that the tensile strength of concrete is lower than the com-pressive strength,the tensile zones should also be enhanced by lin-ings.The position and length of the shear zone is shown in Section3.2.The tensile zone is presented in Figs.8–10.The point of contraﬂexure is on the left edge of the tensile zone.In this experiment,the main rupture path is on the right as shown in Fig.7.The distance between the main rupture path and the point of contraﬂexure has a simple relation with dip angles by linearﬁt-ting,expressed as D p=À0.833a+72.08.The length of the tensile zone is similar to that of the shear zone.Linings should be strengthened when a tunnel goes through normal faults in shear or tensile zones.Results obtained from this experiment have useful applications in tunnel lining design and construction.4.2.Hoop strainsHoop strain gauges are arranged in Sections#1to#6.For each section,four gauges are placed on the top,bottom,left,and right sides of the tunnel.Fig.11shows the plot for lining hoop strain versus fault vertical displacement with a75°dip loading angle. When the fault vertical displacement is small and increasing,the hoop strain gradually increases initially and then tends to stabilize in the end.Sections#2to#5are greatly affected by faults with rel-atively larger strains,whereas Sections#2to#4are all subjected to compression failures.Hoop strain data on the top of#5is so large that the strain gauges are broken down under tensions when fault displacement reaches30mm.However,Sections#1and#6 are far from the fault zone.Therefore,their strains are small.Fig.11shows that strains on the left and right of the tunnel are relatively symmetric in most sections except in Section#2.Strains in the vault of Section#5increase dramatically and reach the ten-sile limit of the gauge with a fault displacement of10mm.All other strains are relatively small.All compressive strains appear to be below the limit with no compression failures.Thus,hoop strains of the tunnel for75°dip angle are small without causing any failure.For60°and45°dip angles,hoop strains are similar to those for the75°dig angle.Some measuring points have large tensile strains or even tensile failures,but no compressive failures occur.The main difference is that more tensile failures occur in60°and45°dip angles.For conciseness,discussions of hoop strains for the 60°and45°dip angles are omitted from this paper.4.3.Failure patternsFig.12shows theﬁnal failure state of the tunnel.Lines D1and D2represent the vertical lines that enclose ruptures on both sides of the shear zone.When the fault dip angle is75°,lining damage mainly occurs within the foot wall zone,with a distribution length of22cm that is approximately0.9times the width of the tunnel cross section. When the dip angle is60°,lining damage mainly occurs within the shear zone and the foot wall zone.The tunnel in the hanging wall zone has minimal damage.The failure zone length along the tunnel axis in the foot wall is1.5times the width of the tunnel. The tunnel in the hanging wall zone is also damaged slightly.When the dip angle is45°,lining damage mainly occurs within the shear and foot wall zones.The tunnel in the hanging wall zonehas minimal damage.One diagonal crack and several longitudinal cracks occur in the shear zone.Circumferential cracks occur in the foot wall zone;most do not penetrate through the tunnel.Length of failures of the tunnel in the foot wall zone,respectively,is2.8 times the width of the tunnel.The tunnel in the hanging wall zone is damaged slightly.(a)70° dip angle(b)60° dip angle(c)45° dip angleFig.12.Tunnel failure of different dip angles.424X.Liu et al./Tunnelling and Underground Space Technology49(2015)417–425The hanging wall of the normal faults slips because of gravity. The relatively large fault displacement leads to bending and shear-ing in the tunnel lining.As mentioned,the tunnel cross sections in the hanging wall zone and shear zone are subjected to sagging. Tunnel cross sections in the foot wall zone are subjected to hog-ging.As a result,tension and compression stresses caused by bend-ing often lead to circumferential cracks and lining crushes.In addition,the tunnel in the shear zone is subjected to shear defor-mation and diagonal cracks.Thus,tunnel damage under normal fault movement with a dip angle of75°is mainly caused by bend-ing failure.Damage when the dip angle is60°and45°is caused by combining bending failure and shearing failure.5.ConclusionsBased on small-scale model experiments,the propagation fea-ture and location of fault ruptures in loose strata over an active normal fault were studied.The results show that more than one fault rupture appears as a result of normal fault activity.Those rup-tures extend to the ground surface and form a triangular shear zone.Tunnel lining that runs through fault zones suffer large dif-ferential displacement,which leads to bending failure or shearing failure,especially in the shear and foot wall zones.The key observations and conclusions from the present study, signiﬁcant for tunnel designing work,are as follows:(1)Strata surface ruptures occur depending on fault displace-ment rather than on fault dip angles.Theﬁrst rupture prop-agates through the strata as vertical bedrock displacement reaches approximately 4.4%of the strata thickness from the fault tip.The damage of the strata from the earth surface has a length of0.64times the tunnel width for the75°case and3.24times for the45°case.(2)Ruptures produced by normal fault propagation in overlyingloose strata are not unique;more ruptures appear as the fault dip angle decreases.Most ruptures bifurcate at the bot-tom of the sand box.Between bifurcated rupture surfaces, severe shear deformation occurs in the strata,which forms an inverted triangle deformation zone.The length of the shear zone increases as the fault dip angle decreases,which has a linear relation with the dip angle of the fault.In Section3.2and Table1,the process of determining the posi-tion and range of the shear zone is summarized.(3)Strata-tunnel-fault can be seen as a beam on an elastic foun-dation.The longitudinal bending moment in the hanging wall and shear zone is subjected to sagging,while that in the foot wall zone is subjected to hogging.The position of the inﬂection point can be determined using the simulation formula mentioned in Section4.1.Besides,as the normal fault moves downward,the tunnel lining also suffers large shearing force.When theﬁrst rupture reaches the ground surface,tunnel lining damage occurs in the shear and foot wall zones.(4)Tunnel failure modes and crack positions appear to changewith fault dip angles.Tunnel damage with a dip angle of 75°is mainly caused byﬂexure in the foot wall zone,which induces circumferential cracking within the tunnel vault with a longitudinal distance of0.9times the width of the tunnel cross section.Failures when the dip angle is60°and45°are caused by combining bending and shearing forcein the foot wall and shear zones,inducing circumferential and diagonal cracking in the tunnel vault,middle,and bot-tom.The difference is that the longitudinal damage range in the foot wall zone is1.5times the width of the tunnel cross section for the60°case,whereas it is2.8times for the45°case.(5)For tunnels under similar conditions,designing a lining sup-port system,including determining the weak parts and fol-lowing reasonable structural parameters,is important to restrict normal fault movements.When the dip angle is 75°,the lining in the foot wall should be reinforced by strengthening the bending stiffness,especially for the tunnel vault part.For the60°and45°cases,the lining both in the shear and foot wall zones should be reinforced by strength-ening the bending and shearing stiffness.The range of lining, which should be reinforced in the shear zone or the foot wall,is calculated in Sections3.2and4.3.At the present stage,this paper lacks a comparison between the model tests and the real tunnel lining measurements because no exact data have been reported on damages induced by nor-mal fault activities.This detail will be our main concern in the next step of our research.AcknowledgmentThis study is mainly supported by the National Natural Science Foundation of China with Grant No.51278377.The advice,com-ments,and assistance provided by the editor and two anonymous reviewers have signiﬁcantly strengthened the scientiﬁc soundness of this paper.Their efforts are gratefully acknowledged. ReferencesBray,J.D.,Seed,R.B.,Cluff,L.S.,Seed,H.B.,1994a.Earthquake fault rupture propagation through soil.J.Geotech.Geoenviron.120(3),543–561.Bray,J.D.,Seed,R.B.,Seed,H.B.,1994b.Analysis of earthquake fault rupture propagation through cohesive soil.J.Geotech.Geoenviron.120(3),562–580. Burridge,P.B.,Scott,R.F.,Hall,J.F.,1989.Centrifuge study of faulting effects on tunnel.J.Geotech.Geoenviron.115(7),949–967.Guo,E.D.,Feng,Q.M.,Bo,J.S.,Hong,F.,2001.Seismic test of soil site rupture under fault displacements.Earthq.Eng.Eng.Vib.21(03),145–149.Johansson,J.,Konagai,K.,2007.Fault induced permanent ground deformations: experimental veriﬁcation of wet and dry soil,numericalﬁndings’relation to ﬁeld observations of tunnel damage and implications for design.Soil Dyn.Earthq.Eng.27(10),938–956.Lee,J.W.,Hamada,M.,2005.An experimental study on earthquake fault rupture propagation through a sandy soil deposit.JSCE,Struct.Eng./Earthq.Eng.22(1), 1s–13s.Lin,M.L.,Chung,C.F.,Jeng,F.S.,2006.Deformation of overburden soil induced by thrust fault slip.Eng.Geol.88(1–2),70–89.Lin,M.L.,Chung,C.F.,Jeng,F.S.,Yao,T.C.,2007.The deformation of overburden soil induced by thrust faulting and its impact on underground tunnels.Eng.Geol.92 (3–4),110–132.Liu,X.Z.,Hamada,M.,2004.Experiments on rupture propagation of active faults in soil.Chinese J.Geot.Eng.26(03),425–427.Roth,W.H.,Scott,R.F.,Austin,I.,1981.Centrifuge modeling of fault propagation through alluvial soils.Geophys.Res.Lett.8(6),561–564.Taniyama,H.,Watanabe,H.,2002.Deformation of sandy deposits by reverse faulting.JSCE,Struct.Eng./Earthq.Eng.19(2),209s–219s.Wang,Y.B.,Wang,Y.,Li,J.C.,Zhan,Y.Z.,2000.Characteristics of ground ruptures caused by the1999M7.3earthquake of Jiji,Taiwan.Seismol.Geol.22(02),97–103.Zhang,P.Z.,Xu,X.W.,Wen,X.Z.,Ran,Y.K.,2008.Slip rates and recurrence intervals of the Longmen Shan active fault zone,and tectonic implications for the mechanism of the May,12Wenchuan earthquake,2008,Sichuan,China.Chin.J.Geophys.Ch.51(4),1066–1073.X.Liu et al./Tunnelling and Underground Space Technology49(2015)417–425425。

断层宽度对跨断层隧道错动反应特性影响的数值模拟

关键词：断层宽度；走滑断层；错动；隧道；数值模拟中图分类号：Ｐ６４２文献标志码：Ａ文章编号：１６７１ — ７６２７（２０１３）０３—００６１ — ０５
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Ａｂｓｔｒａｃｔ：ＩｎｏｒｄｅｒｔｏｓｔｕｄｙｔｈｅｅｆｆｅｃｔｓＯｔｆａｕｈｗｉｄｔｈｏｎｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆａｃｒｏｓｓ — ｆａｕｈｒｏｃｋｔｕｎｎｅｌｄｕｅｔｏ
ｔｈｅｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆａｃｒｏｓｓ－－ｆａｕｌｔｒｏｃｋｔｕｎｎｅｌｉｎｓｔｒｉｋｅ－－ｓｌｉｐｆａｕｌｔｍｏｖｅｍｅｎｔｗｅｒｅａｎａｌｙｚｅｄｂｙｃｈａｎｇｉｎｇｔｈｅ
（南京工业大学地质工程研究所，江苏南京２１０００９）
摘要：为了研究断层宽度对跨断层岩体隧道错动反应特性的影响，利用大型有限元软件ＡＢＡＱＵＳ，建立了断层错

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动区高度分别为１．１８３ｍ，故可反映出该结论的正确７２和１．６
性。
图４，该断面隧道埋深约为３．（６６ｍ隧道顶至地表的距离）２。
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３５问置５的答复．围岩现场试验断面在进口段，而围岩现场实测部分测点
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基于能量分析方法的跨断层隧道震害特性分析

：／ＤＯＩ１０．１３２１９．ａｔ．２０１７．Ｓ１．０１８ｊｇｊｇｙ（）中图分类号：３９５３２０１７Ｓ１００４８００３Ｕ４５２．２８文献标识码：Ａ文章编号：１６７２－－－
０９１３２０１６收稿日期：－－，王树强（男，工程师１９７５—）作者简介：
国防交通工程与技术４０１７增刊１８２
· 实例分析 · 基于能量分析方法的跨断层隧道震害特性分析王树强破坏的发生模式，就必须研究岩体的能量积聚和释放过程。隧道围岩在承受外部荷载之前，岩体单元存储的应变能为：１１）１１ σ σ σ １［（Ｕ＝ σ ε＝｛＋＋－＋ σ σ＋（＋Ｅ２２ＥＥＥ μ ＥＥ１１１）｝（）４ σ σ＋（＋） σ σ］ＥＥＥ在隧道围岩承受外部荷载的过程中，围岩岩体一定会发生一些损伤，引入常规损伤变量 ω ｉ来考虑式中：损伤对岩体加载的弹性模量Ｅｉ＝（Ｅ０。１－ω ｉ）Ｅ０为岩体单元无损伤时的初始弹性模量。为推导方便，先暂时假设泊松比 μ 不受损伤影响，有：１｛σ σ σ １２３（１＋＋＋－μ［２１－ω Ｅ０１－ω １１ ω ω －－１２３１１１）１） σ σ ＋ σ σ １２＋（２３＋１－ω １－ω １－ω ２２３（１＋１）｝（）５ σ σ １３］１－ω １－ω １３为方便工程应用，考虑损伤沿主应力方向的平均效应，令：

断层错动及地震作用下隧道力学特性研究

第 63 卷摇第 11 期 2019 年 11 月文章编号:1004 2954(2019)11 0138 07铁道标准设计 RAILWAY摇 STANDARD摇 DESIGNVol. 63摇 No. 11 Nov. 2019断层错动及地震作用下隧道力学特性研究周佳媚, 程摇毅, 邹仕伟, 周摇瑶, 黄摇柯( 西南交通大学交通隧道工程教育部重点实验室,成都摇 610031)摘摇要:依托国外某穿越走滑断层的高速铁路隧道,利用 FLAC3D 建立三维有限元模型,通过在断层两侧施加强制位移,研究在走滑断层错动作用下的隧道衬砌力学特性,并基于此对隧道在地震波作用下的动力响应规律进行动力分析,最终得到依托隧道的抗错动及抗震加固长度。

结果表明,在走滑断层错动作用及地震动作用下,衬砌内力及应力在断层破碎带与上下盘交界面处达到峰值,并随着监测断面沿轴线方向远离断层时逐渐趋于稳定。

随着断层错动量的增加,衬砌内力与应力逐渐增加;随着输入地震波方向与隧道轴线夹角的增加,衬砌内力与应力逐渐减小。

最终得出,断层错动 0郾 1 m 时,断层两侧隧道加固长度为 3郾 7D( D 为隧道内径) ;断层错动 0郾 25 m 时,隧道加固长度为 4郾 5D;断层错动 0郾 5 m 时,隧道加固长度为 5郾 2D。

关键词:高速铁路; 铁路隧道; 走滑断层; 地震动力; 加固长度中图分类号:U451摇摇文献标识码:A摇摇 DOI:10. 13238 / j. issn. 1004-2954. 201901180006Research on Mechanical Characteristics of Tunnel under Fault Movement and SeismicZHOU Jiamei, CHENG Yi, ZOU Shiwei, ZHOU Yao, HUANG Ke( Key Laboratory of Transportation Tunnel Engineering Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China)Abstract: This paper focuses on the mechanical characteristics of the tunnel lining under strike鄄slip faultmovement by establishing a 3D finite element model with FLAC3D and adding forced displacement. Onthis basis, the dynamic response rules of the tunnel to seismic are researched with the dynamic analysismethod with reference to the the high speed railway tunnel through strike鄄slip fault zones in a foreigncountry. Finally, the reinforced length of the tunnel under fault movement and seismic is determined.The research results show that: the internal forces and stresses of the lining reaches the peak when thetunnel is located on the interface of the surrounding rock and the fault fracture zone, and graduallystabilizes with the monitoring section moving away from the fault zone along the tunnel axis. The internalforces and stresses of lining increases gradually with the increase of the fault displacement; the internalforces and stresses of lining decreases gradually with the increase of the angle between seismic directionand tunnel axis. It is concluded that the收稿日期:2019 01 18;修回日期:2019 02 10 作者简介:周佳媚(1973—) ,女,教授,2004 年毕业于西南交通大学土木工程学院桥梁与隧道工程专业,工学博士,主要研究方向为地下工reinforced length is 3郾 7, 4郾 5 and 5郾 2 times of the inner diameter of the tunnel respectively, when程设计、施工,E鄄mail:tmzjm@ home. swjtu. edu. cn。

新疆柴窝堡盆地南缘断层晚第四纪的活动特点及滑动速率研究

新疆柴窝堡盆地南缘断层晚第四纪的活动特点及滑动速率研究新疆柴窝堡盆地南缘断层是地质学界关注的一个研究热点，其晚第四纪的活动特点及滑动速率对于了解地震活动及地壳运动有着重要意义。

本文将从断层的活动特点和滑动速率两个方面展开研究，以提供准确的回答。

首先是关于新疆柴窝堡盆地南缘断层晚第四纪的活动特点。

根据前人的研究成果，该断层在晚第四纪期间呈现明显的滑动活动。

断层面呈现出剪切痕迹，沿断层线分布有明显的断裂岩屑。

断层两侧岩体存在不同程度的错动现象，表明了断层对岩石的剪切变形作用。

此外，地球表面通过同震形变观测等手段，也可以发现断层线两侧存在不同的地形起伏，形成了非常明显的地形切断。

对于滑动速率的研究，可以通过多种方法进行。

一种常用的方法是通过测量断层两侧地质地形的异动以及确定各个时代地层的位错量，来推算出断层的滑动速率。

比较常见的方法是利用断层两侧断层搬运物的位移量与地层的位错量进行关联，从而确定滑动速率。

同时，还可以应用地层同震形变观测数据，结合历史地震事件分析，来推算出断层的滑动速率。

这些方法可以提供关于断层活动速率的近似数值。

据已有的研究数据显示，新疆柴窝堡盆地南缘断层晚第四纪的滑动速率较为显著。

根据测量的结果，该断层的滑动速率约为每年几毫米至十几毫米之间。

这一速率相对较快，表明断层在晚第四纪期间发生了较为频繁的运动。

而且，断层滑动的速率变化可能存在非均匀性，可能在不同时期呈现出不同的速率。

此外，断层的活动特点及滑动速率还与区域构造背景有关。

新疆柴窝堡盆地处于腾冲-柴达木地块与库车-吐哈地块的相互碰撞带，该地区晚第四纪构造活动较为剧烈。

这种构造背景使得断层在晚第四纪期间表现出较大的位移和滑动速率。

同时，还存在着板块的亚断裂和地质构造的调整，这些因素也促进了断层活动的强烈性。

综上所述，新疆柴窝堡盆地南缘断层晚第四纪的活动特点及滑动速率研究得出了以下结论：断层在晚第四纪期间发生了较为频繁的滑动，表现为明显的剪切痕迹、断裂岩屑和地形切断等特征；滑动速率在每年几毫米至十几毫米之间，可能存在非均匀性；而区域构造背景的作用推动了断层的活动。

采动下断层岩体响应演化及顶板安全控制研究

wall in different areas and the control technology of adjusting the mining parameters,strengthening the support and grouting in the broken zonthe fault zone safely,which has achieved remarkable economic benefits.
隙赋存极其复杂且产生显著劣化效应,采动下断层
为研究对象,采用理论分析和数值模拟的方法,研究
活化程度及断层岩体响应规律不清,断层影响区成
采动下断层岩体活化响应力学机制,分析不同推进
稳定性有显著的影响 [2-3] 。由于断层岩体中节理裂
为事故多发区域
[4]
。弄清采动引起断层岩体活化机
制和响应规律,可对断层区事故隐患超前预警,采取
(3)
考虑顶板见方破断,将 a = b 代入公式(1) 、公式
(2) 、公式(3) ,得到:
x C-A = k 1 a = 0. 35b
x C-B = (1 -k 1 ) a = 0. 65b
P C-A = 28. 28M P / b 2
P C-B = 41. 33M P / b 2
图 1 采动与断层相互作用结构模型
Key words:mining action;fault activation;response characteristics;evolution law;sub-regional control
组成地壳的岩层或岩体因地壳的运动而产生断
合理的防治措施。相关专家学者分析了断层形成过
。断层在形成中经历复杂的运动过程,

断层位错量对跨断层隧道的影响

断层位错量对跨断层隧道的影响张云飞;陈新民;袁宗盼【摘要】在几何相似比为100、断层倾角为90°的情况下,进行了断层位错量对跨断层隧道影响的模型试验.介绍了围岩模型材料的相似常数的选取及设计、隧道衬砌的设计、加载方案.对取得的衬砌应变数据进行处理分析.结果表明:不同位错量下隧道衬砌拱腰的纵向应变分布规律一致,隧道衬砌应变和位错量成正相关;破碎带两侧不同盘处的隧道衬砌的应变呈现反对称分布;应变最大位置处即在断层破碎带处.【期刊名称】《南京工业大学学报（自然科学版）》【年(卷),期】2019(041)001【总页数】6页(P129-134)【关键词】相似常数;断层位错量;跨断层隧道【作者】张云飞;陈新民;袁宗盼【作者单位】南京工业大学交通与运输工程学院,江苏南京 210009;南京工业大学交通与运输工程学院,江苏南京 210009;南京工业大学交通与运输工程学院,江苏南京 210009【正文语种】中文【中图分类】TU45隧道等地下工程穿越断层或接近断层的现象越来越普遍,地震活动不断加强,导致断层活化引起地下工程破坏的情况越来越突出。

很多学者开始从事跨断层隧道的研究。

熊田芳等[1]研究了西安地铁二号线穿越断层的隧道,采用1∶50几何相似比进行了物理模型试验,开展了断层活动下隧道正交穿越断层时围岩和衬砌相互作用的机制研究。

信春雷等[2]通过分析围岩与隧道结构的地震加速度响应,震动应变响应以及隧道结构的震后破坏形态,以无抗减震措施和无断层为对比例,对直立与倾斜走滑断层处设置的套管式可变形抗减震措施进行了系统研究。

刘学增等[3]用有限元分析软件Abaqus建立穿越活动断裂带隧道模型,根据具体隧道相关地质资料,分析断层不同错动位移对隧道结构受力影响,围岩对隧道压力分布情况以及隧道塑性应变发展规律。

李小军等[4]用有限元方法对断层基岩错动引发上覆土层破裂过程进行数值模拟,展示场地土层破裂形成和扩展特征,以及场地地表出现破裂并不一定形成土层贯通破裂的地震现象。

穿越活动断层山岭隧道破坏机制及其安全性分析

穿越活动断层山岭隧道破坏机制及其安全性分析山岭隧道穿越活动断层时,由于受到活动断层的错动作用,隧道结构与断层交界面附近容易出现应力集中现象。

研究跨活动断层的隧道结构抗减震技术是地下工程抗震的难题之一。

本文通过结合常用的抗减震措施,提出了具有综合性的多级抗减震可变结构,并展现相关的数值模拟分析,得出的结论主要有:(1)基于弹性地基梁理论,利用双曲线函数对弹性地基梁的挠度微分方程进行求解,得出隧道结构的纵向内力表达式。

(2)通过比较在峰值加速度为0.3g地震波作用下与断层错动量为0.5m作用下隧道结构的应力,确定断层错动是引起隧道结构破坏的主要原因。

通过数值模拟,研究了在不同的断层错动条件下,包括:断层错动速度、断层宽度、断层倾角、断层错动量和断层错动形式,断层错动对隧道结构所造成的应力影响以及应力分布规律,得出断层的错动量与错动形式对隧道结构的受力影响最大。

根据断层错动下隧道结构应力的大小,将隧道结构分为主要影响区域和次要影响区域。

(3)在断层破碎带及其附近了设置多种抗减震措施,将隧道设计成抗减震能力强的抗减震结构。

该结构是:隧道采用了分段施工,隧道截面扩挖,设置0.3m厚减震层,在隧道主要影响区域注浆2m厚,次要影响区域注浆1m厚,沿隧道纵向设置减震缝的,分段的隧道结构在设置减震缝处允许自由移动。

通过数值模拟,验证该抗减震结构在断层错动下的安全性。

数值模拟表明,该结构基本上能在断层宽度为20m、断层错动速度为0.1m/s、错动形式为逆断层错动、错动量为0.5m的断层错动作用下安全工作。

(4)提出在不设置抗减震措施下,对作用在隧道结构的荷载计算进行修正。

本文通过分析认为由作用在隧道结构上的静力荷载到作用在隧道结构上的动力荷载之间存在一个荷载放大系数。

通过断层发生错动前后隧道结构的应力比值,分别求解出错动方式为正断层错动、逆断层错动和走滑断层错动下的荷载放大系数。

(5)根据抗减震结构沿隧道纵向横截面的不同,以及隧道结构应力沿纵向分布的不同,提出抗减震结构在断层错动作用下的位移和内力数学表达式。

深埋地下洞室断裂型岩爆机理的数值模拟

深埋地下洞室断裂型岩爆机理的数值模拟赵红亮;周又和【摘要】针对深部岩体中由断层、节理等不连续性结构面引发的岩爆地质灾害,根据深埋地下隧洞中潜在发震断裂的分布特征和几何形态建立数值分析模型,采用离散元单元法模拟存在刚性平直断裂的深部围岩的开挖响应,并分别考察开挖接近并通过断裂附近时围岩应力状态的变化特征.通过探讨断裂的存在对围岩应力状态改变的作用机理,揭示出断裂型岩爆是开挖面附近一定范围内存在的断裂构造在高应力作用下发生错动,导致能量突然释放,对围岩造成强烈冲击作用的结果,基本与地震的断层“粘滑”机制相类似.【期刊名称】《爆炸与冲击》【年(卷),期】2015(035)003【总页数】7页(P343-349)【关键词】爆炸力学;岩爆机理;离散单元法;地下洞室【作者】赵红亮;周又和【作者单位】兰州大学土木工程与力学学院,甘肃兰州730000;兰州大学西部灾害与环境力学教育部重点实验室,甘肃兰州730000;兰州大学土木工程与力学学院,甘肃兰州730000;兰州大学西部灾害与环境力学教育部重点实验室,甘肃兰州730000【正文语种】中文【中图分类】O383.2随着西部大开发战略的实施,相应带动我国基础设施建设、资源与能源开发正以前所未有的速度蓬勃发展。

受地形、地质条件限制,我国水能资源的开发主要分布于西部高山峡谷地区。

在西部复杂地形和地质条件下建设大型地下工程,不可避免地会出现高应力问题[1-2]。

深部地下隧洞的开挖过程一般处于高地应力状态下,由于开挖卸荷和复杂地质构造作用,围岩中的集中应力会突然释放,使坚硬脆性岩体发生爆裂、松脱、剥离、弹射乃至抛射性破坏等岩爆现象,给隧洞围岩的稳定性和人员设备安全造成严重威胁[3-4]。

以 R.E.Goodman[5]、S.C.Bandis等[6]、谷德振[7]为代表的一大批岩石力学与工程地质学家发现岩体结构对岩体力学有着重要的影响,认为岩体结构是岩体不同于其他材料的本质特点,并控制着岩体的应力场分布状态,进而控制着岩体的稳定性。

断层错动和地震动共同作用下跨断层隧道的损伤分析

断层错动和地震动共同作用下跨断层隧道的损伤分析
陈之毅;郭远鹏
【期刊名称】《防灾减灾工程学报》
【年(卷),期】2023(43)1
【摘要】大量的历史实例表明,跨断层隧道在地震中会受到严重的破坏。

因此,跨断层隧道在断层错动作用下的破坏机理被广泛研究。

然而,对在地震现象中占比最高的构造地震而言,断层错动和地震动是形影相随的,将两者分开考虑存在局限性。

文章采用三维有限元模型模拟并量化了断层错动单独作用、地震动单独作用和断层错动-地震动共同作用三种加载方式下隧道结构的损伤情况,结合耗散能指标对断层错动和地震动共同作用对跨断层隧道的影响展开了分析。

结果表明,在发生断层错动时,地震动对隧道的影响是不可忽略的,在分析中考虑地震动是必要的;断层错动和地震动共同作用时,由于累积损伤,地震动造成的破坏比地震动单独作用时明显加剧。

【总页数】6页(P132-137)
【作者】陈之毅;郭远鹏
【作者单位】同济大学土木工程学院
【正文语种】中文
【中图分类】U459.3;X951
【相关文献】
1.断层宽度对跨断层隧道错动反应特性影响的数值模拟
2.逆断层黏滑错动对跨断层隧道影响机制的模型试验研究
3.逆断层黏滑错动对跨断层隧道影响机制的模型试
验研究4.逆断层错动作用下地铁隧道结构损伤分析5.断层错动作用下穿越断层隧道地震响应特性研究
因版权原因，仅展示原文概要，查看原文内容请购买。

康西瓦断裂错动对近断层隧道影响的数值模拟分析

康西瓦断裂错动对近断层隧道影响的数值模拟分析
王杰;盛俭;赵梦丹;王欣宇
【期刊名称】《地震工程与工程振动》
【年(卷),期】2022(42)3
【摘要】断层错动会对近断层隧道工程造成破坏。

为研究逆断层错动对近断层隧道结构产生的影响,以新疆地区拟建隧道的地质背景为依托,利用ABAQUS有限元软件,建立与逆断层走向平行的隧道结构的力学模型。

针对隧道与断层破碎带的不同间距、不同断层位错量下的隧道结构反应规律和变形特征进行对比分析。

研究结果表明:逆断层错动引起的隧道衬砌结构变形均发生在靠近断层破碎带一侧,随着隧道结构与断层破碎带间距的不断增大,隧道结构受到逆断层错动影响产生的竖向位移和损伤值均不断减小;随着断层位错量的增加产生的竖向位移和损伤值均增大;且受压损伤值始终大于受拉损伤值。

断层错动作用下隧道结构产生损伤破坏的临界位错量为0.8 m,隧道与断层破碎带间距的临界值为30 m。

【总页数】8页(P235-242)
【作者】王杰;盛俭;赵梦丹;王欣宇
【作者单位】南京工业大学交通运输工程学院
【正文语种】中文
【中图分类】U45
【相关文献】
1.断层宽度对跨断层隧道错动反应特性影响的数值模拟
2.正断层错动诱发上覆黏土中隧道变形破坏数值模拟研究
3.走滑断层错动作用下隧道变形的数值分析
4.逆断层错动对隧道工程影响的数值模拟
5.走滑断层错动量大小对铁路隧道结构安全性影响的数值分析
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双洞隧道在断层破碎带的涌水量预测

双洞隧道在断层破碎带的涌水量预测
阮志刚;刘宁
【期刊名称】《铁道科学与工程学报》
【年(卷),期】2022(19)7
【摘要】在断层破碎带中进行隧道开挖,当山岭地下水位较高时,将面临突涌水的风险,所以有必要进行该复杂环境下隧道涌水量的预测与分析。

以隧道与断层的空间等效关系为基础,从渗流影响范围的角度提出断层影响宽度的不同解读。

基于非达西修正和叠加原理,推导双洞隧道在断层不同区域的涌水量预测公式,并与经过断层的某双洞隧道的实测水量对比,验证该公式在双洞隧道遭遇断层带时进行涌水量预测的适用性。

研究结果表明:双洞隧道的渗流量同时受旁洞和断层的影响,其中,左右洞的相互影响会减少单洞的涌水量,而断层则会加大涌水量;当断面内2倍隧道与断层的水平距离a大于半无限含水地层中渗流影响半径R时,断层作为地下水补给边界的影响可以忽略,而当a越小,断层促进渗流的影响会逐渐加大,当隧道直接揭露断层破碎区时涌水量达到最大。

本文计算结果与分析结果可为后续隧道涌水计算与控制提供指导。

【总页数】8页(P1977-1984)
【作者】阮志刚;刘宁
【作者单位】四川交通职业技术学院;贵州大学土木工程学院
【正文语种】中文
【中图分类】U458
【相关文献】
1.岩溶隧道涌水量预测系列论文岩溶隧道涌水量预测方法及适宜性分析
2.花椒坡隧道断层破碎带突泥涌水处治技术
3.火山岩体围岩隧道断层带涌水量计算方法综合研究:以青云山隧道为例
4.丽香铁路花椒坡隧道断层破碎带突泥涌水处治技术
5.隧洞断层破碎带岩体涌水量分析——安哥拉某水电站为例
因版权原因，仅展示原文概要，查看原文内容请购买。

活动断层错动引致土壤与结构互制灾害

活动断层错动引致土壤与结构互制灾害
林铭郎;钟春富;吴杰佑;郑富书
【期刊名称】《福建地质》
【年(卷),期】2010(029)0z1
【摘要】@@ 由历年灾害性地震事件调查资料显示,除了地盘震动、地盘破坏等原因之外,断盘错动导致上覆土层变形,以921集集地震为例,在断层带附近,大多数结构物均遭受到严重损毁.然而少数结构物即使位于断层带,结构体本身却仅有整体位移或转动而未受损.因此断层作用时覆盖断层带上面的土层,在断层作用中所反映的行为与变形对结构物的影响,是该研究的重点.
【总页数】2页(P127-128)
【作者】林铭郎;钟春富;吴杰佑;郑富书
【作者单位】台湾大学土木工程学系,台北,10617
【正文语种】中文
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2.活动断层的地震灾害效应 [J], 杨承先
3.活动断层、地震灾害与减灾对策问题 [J], 徐锡伟
4.活动断层错动引致土壤与结构互制灾害 [J], 林铭郎;钟春富;吴杰佑;郑富书
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穿越活动断裂山岭隧道抗位错机理与方法研究

穿越活动断裂山岭隧道抗位错机理与方法研究本文针对山岭隧道工程抗震领域的关键科学问题,开展关于穿越活动断裂山岭隧道抗位错机理与方法的系统研究。

具体研究内容如下:开展活动断层对隧道工程危害性分析,基于从工程震害分析的立场确认活动断层与隧道震害的相关性,提出隧道工程的地震破裂定量化评价思路;通过解析和数值方法及物理模型试验开展穿越断层隧道破坏机理分析;基于隧道位错破坏机理研究成果,从多角度开展穿越活动断裂山岭隧道抗位错方法研究;针对提出的穿越活动断裂隧道抗位错方法通过多种方式验证了方法的有效性与正确性。

结合活动断裂与隧道工程的相关性,可以评价活动断裂对于隧道工程潜在的危害类型与程度;建立断层破裂参数定量化评价方法,可以推导工程地点的位错量;研究活动断裂带位错量纵向分布,可以确定断层破裂时的影响范围并确定隧道纵向设防范围;通过开展穿越活动断裂隧道破坏机理研究,可以得到穿越活动断裂山岭隧道抗位错方法;通过以上研究,可以综合考虑多方面因素有针对性的推进提出穿越活动断裂隧道抗位错机理与方法研究。

主要工作内容及取得的成果归纳如下:(1)开展了汶川地震及其它典型地震的震害研究,从工程震害的立场研究隧道的震害破坏现象,通过将震害分类,量化归纳分析隧道震害现象,把握活动断层与工程震害相关性和隧道结构震害薄弱部位。

通过整理分析汶川地震、雅安地震等中国西部地区多个不同类型地震,提出了地震震级-地震破裂参数的相关性法则;(2)基于Okada基岩解析方法,通过输入断层的几何参数和物理性质参数计算断层上方表面基岩位错量,建立断层破碎带纵向强变形带宽度的评价方法,根据围岩性质对公式中相关参数进行了标定与修正,并通过数值模拟方法对提出的公式进行验证,同时基于理论计算方法进行不同断层参数和隧道结构参数条件下的隧道位错响应研究,开展穿越断层隧道破坏机理理论分析;(3)通过试验室大比例物理模型试验,以逆断层为研究事例,开展不同位错量作用下的试验研究,分析山岭隧道结构在逆断层粘滑错动条件下的变形、受力和破坏情况,开展了穿越活动断层山岭隧道破坏机理的试验研究;(4)分别从设防基本原则、设防震级和位错量、穿越活动断裂隧道设防距离、抗位错隧道结构优选和隧道抗位错组合变形缝形式等多方面开展穿越活动断裂隧道抗位错方法的研究,提出了隧道穿越活动断裂适用于不同隧道位置的抗位错组合变形缝。