Based on the load model of a uniform isotropic semi-infinite elastic medium,we deduced a calculation of vertical displacement and tilt and proposed a method of calculation of vertical displacements and tilts caused by...Based on the load model of a uniform isotropic semi-infinite elastic medium,we deduced a calculation of vertical displacement and tilt and proposed a method of calculation of vertical displacements and tilts caused by irregular load on the ground or underground at a certain point with two-dimensional and three-dimensional shapes. We compared the difference between the simplified model and the irregular model. Finally,the vertical displacements near the irregular load and the distribution of horizontal tilt are presented.The results show that,compared with the point simplified model,the irregular load model has certain advantages for describing the near field. The establishment of a twodimensional irregular load model can help with the calculation of the modal vector superposition after load scattering. The three-dimensional irregular load model can redistribute load through different weights given to the scattered points after the load scattering,and then obtain displacement with the vector calculation method. The results of vector superposition calculation from the scattered irregular load both in two-dimensions and three-dimensions are all convergent obviously as grids become denser,and it is shown that the calculation method is correct and feasible.展开更多
Models for the gravitational field of Mars moon Phobos were developed using the latest shape model and assuming homogeneous density distribution.Three methods were applied in our study.Comparisons were made between th...Models for the gravitational field of Mars moon Phobos were developed using the latest shape model and assuming homogeneous density distribution.Three methods were applied in our study.Comparisons were made between these methods and all were shown to yield consistent results.Notably,the most accurate shape model of Phobos to date,complete up to degree and order 17 was used for the first time in our analysis.A set of spherical harmonic coefficients up to degree and order 17 were derived for the gravitational field of Phobos.Also considered was the gravitational field on the surface of Phobos.Typical characteristics as well as some pronounced surface features of this irregular-shaped small body could be conveniently identified.The results are readily applicable for such purposes as spacecraft orbit analysis and assessing the dynamical environment of Phobos.展开更多
基金funded by the Earthquake Tracing Oriented Task of Monitoring and Forecasting Department of China Earthquake Administration in 2015(2015020201):the 12th“Five-year Plan”Science and Technology Support Plan of China(2012BAK19B02)
文摘Based on the load model of a uniform isotropic semi-infinite elastic medium,we deduced a calculation of vertical displacement and tilt and proposed a method of calculation of vertical displacements and tilts caused by irregular load on the ground or underground at a certain point with two-dimensional and three-dimensional shapes. We compared the difference between the simplified model and the irregular model. Finally,the vertical displacements near the irregular load and the distribution of horizontal tilt are presented.The results show that,compared with the point simplified model,the irregular load model has certain advantages for describing the near field. The establishment of a twodimensional irregular load model can help with the calculation of the modal vector superposition after load scattering. The three-dimensional irregular load model can redistribute load through different weights given to the scattered points after the load scattering,and then obtain displacement with the vector calculation method. The results of vector superposition calculation from the scattered irregular load both in two-dimensions and three-dimensions are all convergent obviously as grids become denser,and it is shown that the calculation method is correct and feasible.
基金supported by the CAS-DAAD joint scholarship,the National Natural Science Foundation of China (Grant No.10973031)the National High Technology Research and Development Program of China (Grant No.2010AA122206)the Ministry of Education and Science of the Russian Federation (Grant NO.11.G34.31.0021)
文摘Models for the gravitational field of Mars moon Phobos were developed using the latest shape model and assuming homogeneous density distribution.Three methods were applied in our study.Comparisons were made between these methods and all were shown to yield consistent results.Notably,the most accurate shape model of Phobos to date,complete up to degree and order 17 was used for the first time in our analysis.A set of spherical harmonic coefficients up to degree and order 17 were derived for the gravitational field of Phobos.Also considered was the gravitational field on the surface of Phobos.Typical characteristics as well as some pronounced surface features of this irregular-shaped small body could be conveniently identified.The results are readily applicable for such purposes as spacecraft orbit analysis and assessing the dynamical environment of Phobos.
