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用新ＬＤＤＡ（Ｌａｇｒａｎｇｉａｎ Ｄｉｓｃｏｎｔｉｎｕｏｕｓ Ｄｅｆｏｒｍ ａｔｉｏｎ Ａｎａｌｙｓｉｓ）方法模拟了唐山地震断层的破裂、错动和应力释放的整个动力过程． 模拟结果表明， 唐山地震的震源滑动过程在发震断层上各处不一样． 近场位移受断层的曲率影响， 断层凹侧的位移大于断层凸侧的位移． 滑动“过冲现象”在震中处最大， 并向断层两端衰减． 我们发现， 唐山地震断层的破裂速度和应力降与断层上的初始剪应力大小有关． 唐山发震断层的最大动态、准静态位错量和剪应力降均发生在中间部位， 分别是７．１ ｍ 、６．２ ｍ 和８．１ ＭＰａ 、５．４ ＭＰａ， 发震断层的平均准静态位错量和剪应力降分别为４．５ ｍ 和３．３ ＭＰａ， 断层破裂的传播速度从震中向东南和西北方向分别为３．０８ ｋｍ ／ｓ 和１．１８ ｋｍ ／ｓ．
A new LDDA (Lagrangian Discontinuous Deformation Analysis) method was used to simulate the entire dynamic process of the rupture, dislocation and stress release of the Tangshan earthquake fault. The simulation results show that the source slipping process of Tangshan earthquake is not the same everywhere on the seismogenic fault. The near-field displacement is affected by the curvature of the fault and the displacement of the concave side of the fault is greater than the displacement of the convex side of the fault. The slip “overshoot phenomenon” is largest at the epicenter and decays towards both ends of the fault. We found that the fracture speed and stress drop of the Tangshan earthquake fault are related to the initial shear stress on the fault. The maximum dynamic, quasi-static dislocation and shear stress drop of the seismogenic faults in Tangshan all occurred in the middle part, which were 7.1 m, 6.2 m and 8.1 MPa, 5.4 MPa respectively. The average of seismogenic fault The quasi-static dislocation and shear stress drop were 4.5 m and 3.3 MPa, respectively. The propagation velocity of fault rupture was 3.08 km / s and 1.18 km / s respectively from the epicenter to southeast and northwest.