The response of subsoil strata subjected to seismic excitations plays an important role in governing the response of the overlying superstructures at any site. Ground response analysis(GRA) helps to assess the influen...The response of subsoil strata subjected to seismic excitations plays an important role in governing the response of the overlying superstructures at any site. Ground response analysis(GRA) helps to assess the influence of soil characteristics on the propagating seismic stress waves from the bedrock level to the ground surface during an earthquake. For the northeastern region of India, located in the highest seismic zone in the country, conducting an extensive GRA study is of prime importance. Conventionally, most of the GRA studies are carried out using the equivalent linear method, which, being a simplistic approach, cannot capture the nonlinear behavior of soil during seismic shaking. This paper presents the outcomes of a one-dimensional effective stress based nonlinear GRA conducted for Guwahati city(located in northeast India) incorporating the non-Masing load/unload/reload characteristics. The various ground response parameters evaluated from this study help in assessing the ground shaking, soil amplification, and site responses expected in this region. 2D contour maps, which are representative of the distribution of some of these parameters throughout Guwahati city, are also developed. The results presented herein can serve as guidelines for the design of foundations and superstructures in this region.展开更多
Based on the low-cycle fatigue tests of carbon and alloy steels,the cyclic properties of hysteresis energy and its changing rules have been analysed.The mathematical formula of cyclic hysteresis energy of the material...Based on the low-cycle fatigue tests of carbon and alloy steels,the cyclic properties of hysteresis energy and its changing rules have been analysed.The mathematical formula of cyclic hysteresis energy of the materials with different cyclic properties have been presented. The total absorbed energy to failure is associated with the variation of cyclic hysteresis energy.展开更多
文摘The response of subsoil strata subjected to seismic excitations plays an important role in governing the response of the overlying superstructures at any site. Ground response analysis(GRA) helps to assess the influence of soil characteristics on the propagating seismic stress waves from the bedrock level to the ground surface during an earthquake. For the northeastern region of India, located in the highest seismic zone in the country, conducting an extensive GRA study is of prime importance. Conventionally, most of the GRA studies are carried out using the equivalent linear method, which, being a simplistic approach, cannot capture the nonlinear behavior of soil during seismic shaking. This paper presents the outcomes of a one-dimensional effective stress based nonlinear GRA conducted for Guwahati city(located in northeast India) incorporating the non-Masing load/unload/reload characteristics. The various ground response parameters evaluated from this study help in assessing the ground shaking, soil amplification, and site responses expected in this region. 2D contour maps, which are representative of the distribution of some of these parameters throughout Guwahati city, are also developed. The results presented herein can serve as guidelines for the design of foundations and superstructures in this region.
文摘Based on the low-cycle fatigue tests of carbon and alloy steels,the cyclic properties of hysteresis energy and its changing rules have been analysed.The mathematical formula of cyclic hysteresis energy of the materials with different cyclic properties have been presented. The total absorbed energy to failure is associated with the variation of cyclic hysteresis energy.
