含城门洞形裂隙岩体破碎数值分析及机理研究

为研究不同裂纹赋存形式下的含城门洞岩石破碎及裂纹扩展规律,对不同情况下的含裂隙城门洞岩石试样进行单轴压缩数值模拟试验,得到裂纹扩展规律、声发射规律及应力—应变规律。结果表明,根据数值模拟中的声发射规律,主裂纹主要是拉破坏,翼裂纹、反翼裂纹及远场裂纹主要是拉剪复合型破坏;裂隙的存在降低了试样的峰值强度,各组试样(试样B、C、D系列)的平均峰值强度较不含裂纹试样(试样A系列)下降百分比分别为11.3%、7.8%、12.6%;侧边裂纹产生在靠近顶拱处,底边裂纹越靠近边墙,及顶拱裂纹的裂纹角度越低,试样的峰值强度越低,在实际工程中,对于这些位置产生的裂纹应加强防护,防止灾害的产生。

Numerical Analysis and Mechanism Study on Fracture of Fractured Rock Mass Containing Chengmen Cave

In order to study the law of rock fracture and crack propagation in Chengmen cave under different crack occurrence forms, the uniaxial compression numerical simulation tests of rock samples with cracks in Chengmen cave under different conditions were carried out, and the crack propagation law was obtained. The acoustic emission law and stress-strain law show that according to the acoustic emission law in numerical simulation, the main crack of the main crack is tensile failure, and the wing crack, reverse wing crack and far-field crack are mainly tension-shear composite failure. The existence of cracks reduces the peak strength of the samples, and the average peak strength of each group of specimens (specimen B series, specimen C series, specimen D series) is higher than that of the specimen without crack (specimen A series). the percentage decrease was 11.3%, 7.8% and 12.6%, respectively. The side crack occurs near the top arch, the closer the bottom crack is to the side wall, and the lower the crack angle of the top arch crack is, the lower the peak strength of the specimen is. In practical engineering, the protection of the cracks produced at these positions should be strengthened. Prevent the occurrence of disasters.