中国规范CPT砂土液化判别模型的改进与概率形式  

Improvement and probabilistic form of CPT-based liquefaction evaluation model in Chinese code

作　　者：赵泽宁 段伟 蔡国军[2,4] 武猛 刘松玉 ZHAO Zening;DUAN Wei;CAI Guojun;WU Meng;LIU Songyu(Department of Civil and Environmental Engineering,The Hong Kong University of Science and Technology,Hong Kong,China;Institute of Geotechnical Engineering,Southeast University,Nanjing 211189,China;College of Civil Engineering,Taiyuan University of Technology,Taiyuan 030024,China;School of Civil Engineering,Anhui Jianzhu University,Hefei 230601,China;School of Earth Sciences and Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]香港科技大学土木与环境工程系,中国香港 [2]东南大学岩土工程研究所,江苏南京211189 [3]太原理工大学土木工程学院,山西太原030024 [4]安徽建筑大学土木工程学院,安徽合肥230601 [5]河海大学地球科学与工程学院,江苏南京210098

出　　处：《岩土工程学报》2025年第4期869-876,共8页Chinese Journal of Geotechnical Engineering

基　　金：国家杰出青年科学基金项目(42225206);国家自然科学基金项目(52108332,42472349)。

摘　　要：静力触探(CPT)因其高效可靠等优点被广泛用于评估砂土液化势。目前中国常用的《岩土工程勘察规范》中典型CPT方法(岩规法)在涉及细粒和深层土的液化判别结果方面存在不合理性,并且结果难以整合到概率风险评估中。本研究考虑细粒含量、不确定性和采样偏差的影响,基于贝叶斯加权最大似然估计法,建立CPT双曲线概率模型以改进岩规法,并推荐采用液化概率(PL)=15%所对应的临界锥尖阻力表达式作为确定性方法。最后用实际案例验证所提模型的可靠性。结果表明:CPT双曲线模型中的临界锥尖阻力随深度增加逐渐增大并稳定,更能反映土体的动力特性。模型适用范围更广,可用于深层土和细粒含量较高的土,准确性高于岩规法和国际通用的Robertson和Wride方法。在不确定性较高的场地,概率模型在一定程度上可以作为确定性模型的替代或补充。The cone penetration test(CPT)is commonly used to evaluate sand liquefaction potential due to its efficiency and reliability.The typical CPT method(Chinese code method)shows unreasonable results in fine-grained and deep soils,and the results are difficult to be integrated into probabilistic risk assessments.In this study,a novel CPT hyperbolic probabilistic model is proposed to improve the Chinese code method based on the Bayesian weighted maximum likelihood estimation by considering the effects of fines content,the uncertainties and sampling bias.The critical cone tip resistance corresponding to a liquefaction probability(PL)of 15%is recommended as the deterministic method.Case studies demonstrate the reliability of the proposed method.The results show that the critical cone tip resistance of the CPT hyperbolic model increases with the depth,and gradually stabilizes,which can better reflect the dynamic propertices of soils.The model can be applied to deep and high-fines-content soils,and the performance is better than the Chinese code method and widely-used Robertson and Wride's method.For sites with high uncertainties,the probabilistic models can be used as an alternative or supplement to deterministic ones.

关 键 词：砂土液化 静力触探 双曲型模型 概率 细粒含量 

分 类 号：TU413[建筑科学—岩土工程]