【作者】 孙宪春；

【导师】 万力；

【作者基本信息】 中国地质大学（北京） ， 地下水科学与工程， 2008， 博士

【摘要】 文中采用矩形、菱形、椭圆形位移加载模式分别对钢筋混凝土柱进行了拟静力实验。实验设备是美国MTS公司生产的电液伺服结构实验系统,在试件上安装了独立的位移传感器。实验中使用的是拟静力实验控制软件TUST和多维拟静力实验控制软件TUMT。通过对实验结果的分析,得到以下结论:1、施加轴力的试件滞回耗能曲线比较饱满,耗能能力较强,延性特性明显;施加扭转的试件,双水平方向的耗能能力较弱,表现出脆性的破坏特征。2、施加扭转的试件,当扭矩超过峰值点后下降很快,扭转耗能较差,而双水平方向的耗能较强,但是不如施加轴力作用下的滞回耗能强。3、在相同的加载模式下,扭转作用产生的损伤大于轴力作用下产生的损伤;随着加载循环周数的增多,试件的损伤有加快的趋势;在不同的加载模式下,只考虑取最不利的破坏状态计算的损伤指标相差不大,准确判断试件的破坏特性需要参照实际的破坏情况。4、钢筋混凝土柱在不同的加载模式下,不同加载方向计算的能量曲线不同,因此不能只是以混凝土柱一个方向消耗能量的多少作为构件抗震能力的依据。5、扭转滞回曲线出现较长的滑移段,中间捏拢,耗能能力差。钢筋混凝土柱两个受弯方向的滞回曲线形状呈梭形,滞回环饱满。在逐级增大的加载循环中,两个水平方向的抗弯能力衰减相对较慢,而抗扭能力衰减相对较快,各试件在扭转作用下的延性最差,扭矩超过峰值后刚度退化很快,表现为脆性破坏。6、用规范方法计算的位移值和实测的位移值相差较大,混凝土柱开裂后,在扭剪作用下刚度变化明显,所以在扭矩较大的情况下,需要考虑扭剪影响;实验结果表明,《钢筋混凝土规范》刚度计算式的截距已不是常数,离散性较大。更多还原

【Abstract】 Three loading paths including rectangle path,diamond path and ellipse path are applied to the reinforced concrete columns in quasi-static test.The actuators and displacement sensors are installed i on the specimens.The control softwares are TUSTand TUMT in the test.The conlusions based on the test results are as follows:1、The specimens have more hysteresis dissipated energy under axial forces than those under torsional forces.2、The torsional moment value decreases rapidly when exceeding the maximum ,whose characteristic reveals brittleness.3、The damage caused by the torsion is larger than under axial force at the same applied loading.The damage evaluation must refer to the on-site situation, because the test results are hard to compare under different loading paths. With the enlargement of displacement, the damage quickens.4、The energy curves derived from the data tested by application of different loading on columns are different,therefore,the evaluation of damage grades must be founded on the entire test results.5、The curves of torsional hysteresis dissipated energy demonstrate long slippage and hold together in the middle.On the contrary, the curves of momental hysteresis dissipated energy,which is like shuttle shape, consume much more energy than those curves.With the development of the applied force, the torsional resistant ability attenuates far greatly and its ductibility becomes worse. The rigidity degenerates rapidly when the maximal torsion moment exceeds the peak value,which makes for a brittle damage to these reinforced concrete columns.6、The displacement data measured in the test are much larger than those calculated by the formulae in reinforced concrete code, especially after cracks produced. The effects of torsion and shear forces affecting columns should be think over on the condition of torsion force playing a much important role.更多还原