Study on the corrected hyperbolic model of liquefaction evaluation for fine-grained sand

Through the investigation and research for seismic liquefaction cases, it is found that a certain amount of fine-grained sand is usually contained in the sand field where the seismic liquefaction occurs. Since the existence of fine particles in sand will affect the distribution of soil particles and the contact of between soil particles, further affect the liquefaction resistance of soil, it is of great practical significance and engineering value to study the seismic liquefaction evaluation of fine-grained sand. Based on the original hyperbolic model of liquefaction evaluation for clean sand, a corrected hyperbolic model of liquefaction evaluation for fine-grained sand is established in this study. Firstly, according to Chi-Chi seismic data, the relationship between clay content and fines content in sand is statistically analyzed, and the fine-grained correction term in the hyperbola model is determined; then the model of liquefaction evaluation for fine-grained sand is established and improved by the regression calculation of data samples, and the applicability of the corrected hyperbolic model is verified; on this basis the results of liquefaction evaluation for deep soil are compared between the corrected hyperbolic model and the simplified method proposed by Seed. The results show that the scope of application of the original hyperbolic model is expanded through the corrected hyperbolic model, and the success rate of seismic liquefaction evaluation in shallow soil is improved; compared with the simplified method proposed by Seed, the corrected hyperbolic model shows the good rationality when the liquefaction evaluation results in deep soil are estimated. •If the fines content is neglected in soil liquefaction, it will result in the conservative result.•The hyperbolic model of liquefaction assessment for fine-grained sand is established.•The modified model can keep the consistent and stable success rate of liquefaction assessment.•The modified hyperbolic model is applicable in high intensity area and in deep soil.