word文档，中文2800字，英文1700字

当梁发生屈服弯曲的时候(也是通常被命名的挠曲), 弯曲的张力此刻通常是在截面下面产生的, 压缩张力是出现发生弯曲应变的的截面上，而拉伸张力则产生在截面底部。 这些张力导致在弯曲应变处产生应力, 使上部截面压缩而下面截面受力集中，因此混凝土的成份中必须含有能抵抗拉伸和压缩应力的功能。
因为混凝土构件 (梁, 墙壁、平板等等) 发生挠曲时，要承受相当大的载荷量, 因此它基本上抵抗拉伸应力必须是通过埋置(通常是钢筋)在受力集中的区域来克服和增强, 因此我们创造一种钢筋混凝土成份。当适当地设计和修改后,当发生弯曲时，这些材料的组成部分将非常充分地发生屈服。

When a beam is subjected to bending moments(also termed flexure),bending strains are produced.Under positive moment(as normally defined),compressive strains are
Produced in the top of the beam and tensile strains are produced in the bottom.
These strains produce stresses in the beam,compression in the top and tension in
The bottom.Bending members must therefore be able to resist both tensile and compressive stresses.
For a concrete flexural member(beam,wall,slab,and so on)to have any significant
Load-carrying capacity,its basic inability to resist tensile stresses must be
overcome By embedding reinforcement (usually steel bars) in the tension zones, we
create a reinforced concrete member. When properly designed and constructed,members composed of these materials perform very adequately when subjected to flexure.