桥用砌体轴心受压应力-应变全曲线试验研究
Experimental study on axial compression stress-strain full curves of the masonry for bridge

为了探究桥用砌体轴心受压下的变形特征,进而建立桥用砌体的本构关系,依据标准试验方法,应用20 000 kN级重载多功能结构实验系统,并加入刚性元件,对1组桥用砌体标准试件进行轴心受压试验。为了尽可能避免桥用砌体试件在下降段发生突然破坏,应力-应变曲线下降段采用等速率位移控制加载,并且增加辅助刚性元件。 得到了桥用砌体试件在受压过程中的开裂特征、变形特征、抗压极限承载力以及比较理想的应力-应变全曲线。试验结果表明:桥用砌体的破坏过程与其他砌体相似,其破坏特征表现为明显的脆性破坏。根据试验现象、试验数据以及试验结果提出了桥用砌体轴心受压的应力-应变全曲线的本构关系模型,该应力-应变全曲线方程采用分段型方程式。对试验数据进行拟合,其结果表明该本构关系与实验结果吻合度高,并且形式简单实用,可为实际工程非线性分析提供参考。
In order to explore the deformation characteristics of compressed masonry for bridge and establish its constitutive relationship, an experimental research was carried out on 1-group masonry for bridge standard test piece under axial compression, 20000KN grade heavy duty multifunctional structure experimental system . The rigid elements were adopted to the experiment which was based on the standard test method. In order to avoid sudden failure of the masonry specimens in descending segment as far as possible, the loading method of displacement control of constant rate was used in descending segment of stress-strain curve, and the auxiliary rigid element was adopted. The crack characteristic, the deformation characteristic, the ultimate bearing capacity under axial compression and ideal stress-strain full curves were obtained. The research results show that the failure process of the masonry for bridge is similar to other masonry, it has significant brittle characteristics. Based on the experimental phenomena, the experimental data and the experimental results,the compressive constitutive relationship of the masonry for bridge is proposed. The curves equation is the sectional form. By fitting the experimental data, the result shows that the constitutive relationship is very close to the experimental results. It is simple and practical, and it can provide a reference for the nonlinear analysis of practical engineering