钢筋混凝土异形柱抗扭性能的数值模拟

基于有限元软件ANSYS,建立压扭作用下钢筋混凝土异形柱抗扭性能的数值分析模型,并对压扭作用下9根异形柱的抗扭性能试验进行数值模拟分析.通过反复试算,提出混凝土异形柱压扭性能数值模拟的模型分析参数,分析轴压比对不同截面形状和尺寸的钢筋混凝土异形柱的开裂扭矩和极限扭矩的影响规律.研究结果表明:数值模型对异形柱的开裂扭矩和极限扭矩预测较准,但对扭矩-扭转角全过程曲线的预测还有待进一步改进;不同截面形状和尺寸的混凝土异形柱的开裂扭矩和极限扭矩随着轴压比的增大均近似呈直线增加,但当轴压比超过0.6时,异形柱的开裂扭矩和极限扭矩反将降低;随着轴压比的增大,异形柱从开裂扭矩发展到极限扭矩的过程缩短.

Numerical Simulation of the Torsional Behavior for Reinforced Concrete Specially-Shaped Columns

A numerical model for the torsional behavior of reinforced concrete columns with special-shaped cross sections under the actions of compression and torque was established by ANSYS.Some key finite element model parameters for the torsional behavior analysis of these specially-shaped columns were suggested through repeated trial numerical analysis of the tests of nine specially-shaped columns.The influence of axial compressive ratio on the cracking torque and ultimate torque of special-shaped columns with different sectional shapes and dimensions was analyzed.The results show that: the cracking torsion and ultimate torsion of specially-shaped columns is well predicted by finite element model,however the prediction of the full process curve of torque-torsion angle needs further improvement.The cracking torque and ultimate torque of specially-shaped columns increase approximately linearly with the increasing of 0~0.6 axial compressive ratio;for axial compressive ratio>0.6,the cracking torque and ultimate torque decrease.The developing process from the cracking torque to ultimate torque of the specially-shaped columns is shortened with the increasing of the axial compressive ratio.