Application of the inversion method to a GPS network for estimating the stress increment in Japan
Application of the inversion method to a GPS network for estimating the stress increment in Japan
复制标题
DOI：
10.1046/j.1365-246x.2001.01337.x
复制
发表时间：
2001-03
影响因子：
2.8
通讯作者：
M. Hori;T. Kameda;T. Kato
中科院分区：
文献类型：
--
作者：
M. Hori;T. Kameda;T. Kato
本文探讨了一种反演方法的适用性，确定应力分布的日本列岛，其变形测量的全国GPS阵列。本文的反演方法与普通反演方法不同，普通反演方法虽然只适用于二维状态，但需要对本构关系进行参数化。严格地证明了不需要本构关系就可以求出应力，并通过对某类材料进行数值模拟和模型实验验证了其有效性和实用性。对于GPS数据，反演方法可以预测与实测位移增量相关的应力增量分布。在假定增量变形为平面应力状态，不存在体积非弹性变形的条件下，利用1997 ~ 1998年的GPS观测数据计算了应力增量，并从数值分析的角度出发，通过改变离散尺度、边界条件等参数，检验了解的有效性。根据实测应变增量与反演应力增量之间的关系，推导出区域本构关系。虽然肯定需要进一步的研究，数值模拟的结果表明，本反演方法的潜在用途。反演方法的局限性时，适用于日本列岛进行了讨论，并提到必要的修改。
SUMMARY This paper examines the applicability of an inversion method of identifying stress distribution to the Japanese Islands, whose deformation is measured by the nationwide GPS array. The present inversion method is different from ordinary inversion, which requires a parametrization of constitutive relations, even though it is applicable only in the 2-D state. It is rigorously shown that stress can be found without using constitutive relations, and the validity and usefulness are verified by carrying out a numerical simulation and a model experiment for a certain class of materials. For the GPS data, the inversion method can predict the stress increment distribution that is associated with the measured displacement increment. Under assumptions of a plane stress state for the incremental deformation and no volumetric inelastic deformation, the stress increment is computed from the GPS array data measured during 1997 and 1998; from the viewpoint of numerical analysis, the validity of the solutions is examined by changing the discretization scale, boundary conditions and other parameters. Regional constitutive relations are deduced from relations between the measured strain increment and the inverted stress increment. While further studies are definitely needed, the results of the numerical simulation suggest the potential usefulness of the present inversion method. The limitations of the inversion method when applied to the Japanese Islands are discussed, and necessary modifications are mentioned.