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根据１９７６年唐山７．８级地震的前兆资料，结合岩石破裂物理、震源物理、构造物理、地震前兆、地震力源、地壳结构等方面的研究结果，采用含有菱形硬包体的饱和水孔隙介质模型，数值模拟了唐山大地震的孕育过程．首先导出了考虑岩石非弹性体积膨胀和应变软化、孔隙水渗透的固－液两相介质的孕震动力学方程组，提出了用增量形式求解该方程组的有限差分法，然后计算模拟了硬包体内含有断层软弱带时的唐山大震的孕育过程，及其时空变化特征．数值模拟结果表明，唐山大地震的孕育主要经历了弹性积累、早期非弹性体积膨胀、断层第１次加速软化（加速破坏和蠕滑）、天津－宁河一带第２次非弹性膨胀、断层第２次加速软化（临震加速破坏和蠕滑）和发震等过程．这里，与断层的加速破坏相对应，孕震介质的某些部分出现了非弹性膨胀的弹性恢复和二次非弹性膨胀．与前兆观测资料比较分析可以发现，上述模拟结果可以比较好地解释实际观测资料的变化特征．同时，数值模拟还进一步揭示了唐山地震孕育场的时空变化规律和复杂图象，为地震前兆场变化的物理机制的研究奠定了基础．
According to the precursory data of the MS7.8 Tangshan earthquake in 1976 and the research results of rock fracture physics, source physics, tectonic physics, earthquake precursors, seismic force sources and crustal structure, a saturated water pore medium containing diamond-shaped inclusions Model to numerically simulate the breeding process of the Tangshan earthquake. First of all, the seismogenic kinetic equations of solid-liquid two-phase medium considering inelastic volume expansion, strain softening and pore water infiltration of rock are derived. The finite difference method for solving this system in incremental form is proposed. The Incidence Process of Tangshan Earthquake with Fault Soft Belt in Inclusion Body and Its Temporal and Spatial Variability. The numerical simulation results show that the inception of Tangshan earthquake mainly experienced elastic accumulation, early inelastic volume expansion, the first accelerated softening (accelerated damage and creep), the second non-elastic expansion in Tianjin-Ninghe area, 2 times to speed up softening (Pro-seismic acceleration damage and creep) and the earthquake and other processes. Here, corresponding to the accelerated failure of the fault, elastic recovery and secondary inelastic expansion of inelastic expansion occurred in some parts of the seismogenic medium. Compared with the precursory observation data, we can find that the above simulation results can better explain the changing characteristics of the observed data. At the same time, the numerical simulation further reveals the spatial and temporal changes and complex images of the pregnant field in Tangshan earthquake, which lays the foundation for the study of the physical mechanism of earthquake precursory field changes.