（土木工程专业英语课件）LESSON11

INTRODUCTION OF BEAMS AND COLUMNS
INTRODUCTION OF BEAMS AND COLUMNS
They are structural members which carry loads that are applied at right angles to the longitudinal axis of the member.
INTRODUCTION OF BEAMS AND COLUMNS
INTRODUCTION OF BEAMS AND COLUMNS
Contraction
Roller
Hinge
INTRODUCTION OF BEAMS AND COLUMNS
Contraction
Roller
Hinge
INTRODUCTION OF BEAMS AND COLUMNS
In the process of beam design, we will be concerned initially with the bending moment in the beam. The bending moment is produced in the beam by the loads it supports. Other effects, such as shear or deflection, may eventually control the design of the beam and will have to be checked. But usually moment is critical and it is, therefore of initial concern.
INTRODUCTION OF BEAMS AND COLUMNS
梁是结构中最常见的构件
作为结构构件，梁承受垂直与构件轴线的荷载
INTRODUCTION OF BEAMS AND COLUMNS
受荷造成梁弯曲
本文中，我们视梁不受轴向力
图11-1a和b 表示一些梁应用的典型例子
INTRODUCTION OF BEAMS AND COLUMNS
idealized form将构件理想化会便于分析或者设计一根梁（或其它结构构件
mathematically 理想模型虽不同但非常接近实际构件，它的优点是可以用数学方法处理
INTRODUCTION OF BEAMS AND COLUMNS
knife-edge or hinge
举例而言，在图11-1a中，梁显示为简单支撑，左端一个固定较刃形支承铰式支承），右端一个滑动铰这种情况，可简单地通过理论解出梁受荷下的抗力，剪力，弯矩和变形。

INTRODUCTION OF BEAMS AND COLUMNS
idealize
Mathematically
pin
knife-edge Hinge Roller
INTRODUCTION OF BEAMS AND COLUMNS
reactions rotation
固定铰支座可提供垂直或水平抗力（但没有旋转约束），滑动铰支座只能提供垂直反力
expansion contraction
膨胀收缩
INTRODUCTION OF BEAMS AND COLUMNS
在建筑中，每个支承一般都能提供垂直和水平反力
不管怎样，由于支承条件的需要，梁的左端依然被视为简单支承。

INTRODUCTION OF BEAMS AND COLUMNS
fixed support
固定支承
INTRODUCTION OF BEAMS AND COLUMNS
approximate 接近
INTRODUCTION OF BEAMS AND COLUMNS
rotation
rotate
expansion
Contraction
shrinkage
INTRODUCTION OF BEAMS AND COLUMNS contract
INTRODUCTION OF BEAMS AND COLUMNS contract
Contraction：
INTRODUCTION OF BEAMS AND COLUMNS
be concerned with
be concerned with：关注，考虑
INTRODUCTION OF BEAMS AND COLUMNS
其它效应，如剪力和位移，也可能最终控制设计，因此也必须校核
critical
但通常弯矩是起控制作用的，所以在最开始就予以考虑
Critical：决定性的，临界的
INTRODUCTION OF BEAMS AND COLUMNS
INTRODUCTION OF BEAMS AND COLUMNS
Girder
大梁Deck girder
板梁
INTRODUCTION OF BEAMS AND COLUMNS
INTRODUCTION OF BEAMS AND COLUMNS Floor beam:
INTRODUCTION OF BEAMS AND COLUMNS Joist:
INTRODUCTION OF BEAMS AND COLUMNS
Lintel:
砖石结构
INTRODUCTION OF BEAMS AND COLUMNS Spandrel: a beam on the outside perimeter of a building
INTRODUCTION OF BEAMS AND COLUMNS
Purlin: a beams that supports a roof, and frames between
INTRODUCTION OF BEAMS AND COLUMNS
INTRODUCTION OF BEAMS AND COLUMNS
INTRODUCTION OF BEAMS AND COLUMNS
beam-column
lateral buckling
eccentric load
INTRODUCTION OF BEAMS AND COLUMNS
beam-column
lateral buckling
eccentric load
INTRODUCTION OF BEAMS AND COLUMNS
struts
支柱（支撑物）
INTRODUCTION OF BEAMS AND COLUMNS S trut
strut chanel：槽钢支撑
INTRODUCTION OF BEAMS AND COLUMNS
posts pillars
标桩立柱（墩柱）
Chord member: 弦杆
INTRODUCTION OF BEAMS AND COLUMNS
posts pillars
标桩立柱（墩柱）
Chord member: 弦杆
INTRODUCTION OF BEAMS AND COLUMNS P osts: 标桩
INTRODUCTION OF BEAMS AND COLUMNS
P illars: 柱
3.(architeture) a tall cylindrical vertical upright and
used to support a structure. ——墩柱、立柱
INTRODUCTION OF BEAMS AND COLUMNS P illars: 柱
INTRODUCTION OF BEAMS AND COLUMNS P illars: 柱
INTRODUCTION OF BEAMS AND COLUMNS
P illars: 柱
3. (architeture) a tall cylindrical vertical upright and used to support a structure. ——墩柱、立柱
INTRODUCTION OF BEAMS AND COLUMNS Double angle ：双角钢
INTRODUCTION OF BEAMS AND COLUMNS
longitudinal centroidal axis 纵向中轴线
INTRODUCTION OF BEAMS AND COLUMNS
eccentricities
（偏心距）
偏心
INTRODUCTION OF BEAMS AND COLUMNS
moment-carrying member
受弯构件
beam-column
压弯柱（偏压柱、压弯构件）
INTRODUCTION OF BEAMS AND COLUMNS Commonly used cross sections for steel
rolled shapes
轧制型材
built-up cross section
组合截面
Rolled shapes：轧制型材
built-up cross section:组合截面
INTRODUCTION OF BEAMS AND COLUMNS
Typical compression cross sections are shown in fig. 11-2.
tie plates lacing bars perforated cover plates
缀板缀条穿孔覆板
INTRODUCTION OF BEAMS AND COLUMNS
In dealing with compression members, the problem of in alignment
成直线
lateral buckling
横向屈曲
INTRODUCTION OF BEAMS AND COLUMNS
The buckling problem is intensified and the load-carrying
eccentric load
偏心加载residual stresses
残余应力。