论文部分内容阅读
准确计算钢筋混凝土细长柱的附加变形,是分析柱承载力和二阶效应的基础。对于无侧移钢筋混凝土柱,由于荷载作用下柱各截面的非线性发展程度不同,各截面的刚度是不同的,为此将柱划分为多个微段,视单个微段为等刚度,建立微段的变形微分方程。根据微段间的变形协调条件得到微段间变形的关系式,解该关系式构成的非线性方程组,可得到规定荷载下柱的变形曲线和附加变形。在此基础上分析了轴力偏心距、柱长细比等对柱承载力和挠曲变形的影响。分析表明:轴力偏心距和长细比越大,柱承载力越小,挠曲变形越大。对按此方法计算的柱两端偏心距相等时附加变形-长细比曲线和柱两端偏心距不等时等效均布弯矩系数-端部弯矩比值曲线进行拟合,给出计算柱附加变形和等效均布弯矩系数的简化计算式,并与已有的试验结果进行了对比。对比表明,柱两端偏心距相等时附加变形简化计算式的计算结果好于我国GB50010—2010规范公式的计算结果,柱两端偏心距不等时等效均布弯矩系数简化计算式考虑了偏心距的影响,计算结果好于采用我国规范GB 50010—2010和美国规范ACI 318-08的计算结果。
Accurately calculating the additional deformation of the reinforced concrete slender column is the basis for analyzing the bearing capacity and the second-order effect of the column. For non-side-shifting RC columns, the stiffness of each section is different due to the different degrees of nonlinear development of each section of the column under load. To this end, the column is divided into several micro-sections, Micro-section of the differential equation. According to the deformation coordination between micro-sections, the relationship between the deformations of micro-sections is obtained. By solving the nonlinear equations formed by the relation, the deformation curve and additional deformation of the column under the specified load can be obtained. Based on this, the influence of axial force eccentricity and column slenderness on the bearing capacity and flexural deformation of the column was analyzed. The analysis shows that the bigger the axial force eccentricity and the slenderness ratio are, the smaller the column bearing capacity is, and the larger the deflection is. When the calculated eccentricity of the two ends of the column is equal, the equivalent deformation moment-slenderness ratio curve and the equivalent uniform bending moment coefficient-end moment ratio curve when the eccentricity of both ends of the column are equal are fitted to give the calculation The simplified calculation formulas of additional deformation and equivalent uniform bending moment coefficient are also compared with the existing experimental results. The comparison shows that the simplified calculation formula of additional deformation when the eccentricity of both ends of the column is equal is better than the calculation result of the formula of GB50010-2010 in our country. The simplified calculation formula of equivalent uniform bending moment coefficient is considered Eccentricity, the calculation result is better than the calculation result of our country standard GB 50010-2010 and American standard ACI 318-08.