波形钢板混凝土黏结滑移性能试验研究与数值模拟分析

Experimental study and numerical simulation on bond-slip behavior between corrugated steel plate and concrete

通过波形钢板混凝土推出试验,对波形钢板混凝土黏结滑移受力机理、黏结强度和黏结滑移本构关系等关键问题进行研究。设计8个推出试件,主要研究波角和波谷长度因素对黏结滑移性能的影响,考察波形钢板波角、波脊和波谷处混凝土黏结性能。结果表明,对于波谷和波脊尺寸相同的波形,当波角为钝角时,黏结强度随着波角的增大而增大;当波角为锐角时,黏结强度随着波角的增大而减小。同时,对于相同波角的波形,黏结强度随着波谷的增大而减小。在微滑移阶段和滑移阶段,波形钢板应变沿埋置长度方向呈指数分布;波脊和波角处的应变要大于波谷轴心处的应变;在破坏阶段、荷载下降阶段和残余阶段,波形钢板应变分布复杂,并且在埋置长度上有过零点现象。根据所有试件加载端和自由端的荷载-滑移曲线试验结果,利用统计回归的方法得到波形钢板混凝土特征黏结强度的计算公式。通过建立力学平衡方程,得知波形钢板黏结应力沿着锚固深度呈指数分布,进一步建立考虑位置函数的黏结滑移本构模型。基于ANSYS有限元软件分别从基准黏结滑移本构关系、考虑位置函数的黏结滑移本构关系对试件进行数值模拟,结果表明考虑位置函数的黏结滑移本构关系更具有准确度。

A series of push-out tests were carried out for the bond mechanism, bond strength and bond-slip constitutive relations between corrugated steel plate and concrete. Eight push-out specimens are designed to study the influences of wave angle and length of wave trough on bond-slip behavior, and the bonding properties at wave angle, wave ridge and wave trough are investigated. The experimental results indicate that, for specimens with the same size of wave trough and wave ridge, bond strength of the obtuse angle specimen increases with the increase of the wave angle;the bond strength of the acute angle specimen decreases with the increase of wave angle. In addition, for the waveforms with the same wave angle, the bond strength decreases with the increase of wave trough. In the micro-slip phase and the sliding phase, the strain of the corrugated steel plate is exponentially distributed along the embedment length. The strains at the wave ridge and the wave angle are greater than that at the axis of wave trough. During the failure stage, the load descent stage and the residual stage, the strain distribution of the corrugated steel plate is complex, and zero crossing phenomenon may appear along the embedment length. According to the experimental load-slip curves at load-end and free-end of all specimens, the calculation formulas of characteristic bond strength are established by statistical regression. By establishing the equilibrium equation of mechanics, it is found that the bond stress of the corrugated steel sheet is distributed exponentially along the embedment depth, and furthermore, a bond slip constitutive model considering the position function is established. Based on the finite element software ANSYS, numerical simulations were conducted for the specimens considering the bond-slip constitutive relation and the bond-slip constitutive relation of the position function. The results show that the bond-slip constitutive relation considering the position function shall be more accurate.