Recent studies using field case history data yielded new criteria for evaluating liquefaction potential in saturated granular deposits based on in situ, stress-corrected shear wave velocity. However, the conditions of...Recent studies using field case history data yielded new criteria for evaluating liquefaction potential in saturated granular deposits based on in situ, stress-corrected shear wave velocity. However, the conditions of relatively insufficient case histories and limited site conditions in this approach call for additional data to more reliably define liquefaction resistance as a function of shear wave velocity. In this study, a series of undrained cyclic triaxial tests were conducted on saturated sand with shear wave velocity Vs measured by bender element. By normalizing the data with respect to minimum void ratio, the test results, in-corporated with previously published laboratory data, statistically revealed good correlation of cyclic shear strength with small-strain shear modulus for sandy soils, which is almost irrespective of soil types and confining pressures. The consequently determined cyclic resistance ratio, CRR, was found to be approximately proportional to Vs4. Liquefaction resistance boundary curves were established by applying this relationship and compared to liquefaction criteria derived from seismic field measure-ments. Although in the range of Vs1>200 m/s the presented curves are moderately conservative, they are remarkably consistent with the published field performance criteria on the whole.展开更多
The road traffic network contains a large number of bridges,and calculating bridge damage using refined models demands significant time and resources.Therefore,developing a rapid evaluation method for the seismic capa...The road traffic network contains a large number of bridges,and calculating bridge damage using refined models demands significant time and resources.Therefore,developing a rapid evaluation method for the seismic capacity of regular bridges has become a crucial scientific challenge.This study presents an approach in which the ductile column is represented by a single degree-of-freedom model with elastic-plastic constitutive characteristics.Utilizing an uncoupled multivariate power function model and a plastic hinge model,a multidimensional power function model for section hierarchical curvature is constructed.Subsequently,the seismic multistage damage constitutive model(SMSD-CM)of member hierarchy is deduced and calibrated through theoretical methods.This model efficiently derives the trilinear constitutive model of components by inputting several crucial parameters.The SMSD-CM accurately simulates the hysteretic curve and displacement time-history under actual seismic conditions and aligns well with pushover analysis results from tests.The efficiency,ease of operation,and accuracy make the model suitable for rapid evaluation of the seismic capacity of regular bridges within the road traffic network.展开更多
基金Project supported by the National Natural Science Foundation of China (No. 10372089), and Department of Education of Zhejiang Province (No. 20010572), China
文摘Recent studies using field case history data yielded new criteria for evaluating liquefaction potential in saturated granular deposits based on in situ, stress-corrected shear wave velocity. However, the conditions of relatively insufficient case histories and limited site conditions in this approach call for additional data to more reliably define liquefaction resistance as a function of shear wave velocity. In this study, a series of undrained cyclic triaxial tests were conducted on saturated sand with shear wave velocity Vs measured by bender element. By normalizing the data with respect to minimum void ratio, the test results, in-corporated with previously published laboratory data, statistically revealed good correlation of cyclic shear strength with small-strain shear modulus for sandy soils, which is almost irrespective of soil types and confining pressures. The consequently determined cyclic resistance ratio, CRR, was found to be approximately proportional to Vs4. Liquefaction resistance boundary curves were established by applying this relationship and compared to liquefaction criteria derived from seismic field measure-ments. Although in the range of Vs1>200 m/s the presented curves are moderately conservative, they are remarkably consistent with the published field performance criteria on the whole.
基金The National Natural Science Foundation of China(No.52208468,52178125)Fundamental Research Funds for Central Universities(No.2242023S20004).
文摘The road traffic network contains a large number of bridges,and calculating bridge damage using refined models demands significant time and resources.Therefore,developing a rapid evaluation method for the seismic capacity of regular bridges has become a crucial scientific challenge.This study presents an approach in which the ductile column is represented by a single degree-of-freedom model with elastic-plastic constitutive characteristics.Utilizing an uncoupled multivariate power function model and a plastic hinge model,a multidimensional power function model for section hierarchical curvature is constructed.Subsequently,the seismic multistage damage constitutive model(SMSD-CM)of member hierarchy is deduced and calibrated through theoretical methods.This model efficiently derives the trilinear constitutive model of components by inputting several crucial parameters.The SMSD-CM accurately simulates the hysteretic curve and displacement time-history under actual seismic conditions and aligns well with pushover analysis results from tests.The efficiency,ease of operation,and accuracy make the model suitable for rapid evaluation of the seismic capacity of regular bridges within the road traffic network.