循环荷载作用下钢筋混凝土短柱受剪性能尺寸效应机理分析

Mechanism analysis for size effect on shear performance of RC short columns under cyclic load FU Li,ZHENG Jiale,WANG Dengfeng

为了研究钢筋混凝土短柱在循环荷载作用下受剪性能尺寸效应产生的机理,应用三维刚体弹簧元法,基于梁-拱模型,对3个不同截面尺寸的钢筋混凝土短柱抗剪作用进行分解,结果表明:应用三维刚体弹簧元法能较好地模拟不同截面尺寸钢筋混凝土短柱在循环荷载下的受剪性能;当达到极限荷载时,随着截面尺寸的增加,以名义剪应力为评判标准的抗剪强度逐渐减小,相比于单调荷载,一次循环后的尺寸效应变化较小,而两次循环(短柱临近破坏)后尺寸效应更加明显,这主要是由于拱模型的抗剪作用急剧下降导致的。

Here,in order to study size effect mechanism on RC short column shear performance under cyclic load,using 3-D rigid spring element method and based on beam-arch model,anti-shear actions of RC short columns with 3 different section sizes were decomposed.The results showed that the 3-D rigid spring element method can better simulate shear performance of RC short columns with different section sizes under cyclic load;when the ultimate load is reached,the shear strength defined as nominal shear stress gradually decreases with increase in section sizes;compared with the monotonic load,the size effect varies less after one cycle,while the size effect is more obvious after two cycles during short column close to failure,the main cause is due to anti-shear action of the arch model sharply dropping.