高温冷却对混凝土剪切性能的影响

Effect of High-Temperature Cooling on the Shear Properties of Concrete

为研究表面裂隙对红砂岩力学行为的影响,采用不同深度的表面预制裂隙红砂岩进行单轴压缩试验,结果表明:预制表面裂隙砂岩试样的峰值强度和弹性模量与完整砂岩试样相比均有不同程度下降,弹性模量随着裂隙深度增加呈二次抛物线下降.砂岩的破坏模式随着预制裂隙深度的增加由劈裂破坏逐渐向剪切破坏转变,试样加载后裂纹主要为翼裂纹和反翼裂纹,反翼裂纹随着裂隙深度增加逐渐由次裂纹发展成为主裂纹,主裂纹与预制裂纹之间的夹角则是先减小后增大.试验结果表明红砂岩表面预制裂隙深度对其力学行为影响较大.

In order to investigate the effect of surface cracks on the mechanical behavior of red sandstone,uniaxial compression tests were conducted on red sandstone specimens with pre-fabricated surface cracks of varying depths.The results indicate that the peak strength and elastic modulus of the pre-fabricated surface crack sandstone specimens decreased to varying degrees when compared to intact sandstone specimens.The elastic modulus exhibited a quadratic decrease with increasing crack depth.The failure mode of the sandstone gradually shifted from splitting failure to shear failure with increasing pre-fabricated crack depth.Cracking patterns observed after loading included wing cracks and anti-wing cracks,with the anti-wing cracks developing into primary cracks as crack depth increased.The angle between the primary cracks and pre-fabricated cracks decreased initially and then increased.Experimental results demonstrate that the depth of pre-fabricated surface cracks has a significant impact on the mechanical behavior of red sandstone.