A distinct element model is developed to simulate the progressive localization of deformation that evolves from shear to compaction bands with respect to confining pressure in porous rocks. The numerical samples with nominal porosities ranging from 0 to 14% in two-dimension, are established by synthesizing breakable grains and compressible macro-pores. The hydrostatic and unconfined tests are conducted to address the two endmembers of deformation behavior, and a broad range of confining pressures are adopted in confined tests so that the whole transition can be observed. The micro-cracking activity and associated energy components are synchronously tracked, to investigate the pure cataclastic deformation under the effects of porosity and confining pressure. Numerical results confirm that the incidental compaction of macro-pore space, originating from grain fragmentation, accounts for the major distinction in failure mode between different porosity samples. Generally, the rise in confining pressure promotes the shear cracking and intra-granular failure, and the increase in porosity facilitates the relative abundances of tensile cracking and inter-granular failure. Shear localization dominates the rupture pattern at low confining pressure regardless of porosity. At high confining pressure, the nonporous sample is characterized by ductile behavior, along with a declined fraction of energy release; whereas the porous samples are featured with macro-pore collapses that relate to surges in both micro-cracking activity and energy release, some of which would eventually coalesce and develop into a compaction band if the conditions (e.g., porosity and contractional displacement) permit.

开发了一个独特的元素模型来模拟变形的局部化，该变形相对于多孔岩石中的围压从剪切带发展到压实带。通过合成易碎的晶粒和可压缩的大孔，建立了二维名义孔隙率范围为0％至14％的数值样本。进行静水压试验和无侧限试验是为了解决变形行为的两个端部，并且在密闭试验中采用了宽范围的密闭压力，以便可以观察到整个过渡过程。同步跟踪微裂纹活动和相关的能量分量，以研究在孔隙度和围压作用下的纯裂变变形。数值结果证实了大孔空间的偶然压实，源于晶粒破碎，解释了不同孔隙度样品在破坏模式上的主要区别。通常，围压的升高促进了剪切开裂和晶内破坏，而孔隙率的增加促进了拉伸开裂和晶间破坏的相对丰度。不论孔隙度如何，在低围压下，剪切局部化均占主导地位。在高围压下，无孔样品的特征是韧性，伴随着能量释放的减少。而多孔样品的特征是大孔塌陷，这与微裂纹活动和能量释放的激增有关，如果条件（例如，