Liquefaction assessments at shallow foundation building sites in the Central Business District of Christchurch, New Zealand
Liquefaction assessments at shallow foundation building sites in the Central Business District of Christchurch, New Zealand
复制标题
新西兰基督城中央商务区浅基础建筑工地的液化评估
DOI：
10.1016/j.soildyn.2016.09.049
复制
发表时间：
2016
影响因子：
4
通讯作者：
M. Cubrinovski
中科院分区：
文献类型：
--
作者：
J. Bray;C. Markham;M. Cubrinovski
2010-2011年坎特伯雷地震序列提供了一个特殊的机会，调查不同程度的液化对建筑环境的影响。在基督城地震中观察到中央商务区（CBD）的显著地面沉降和建筑物损坏。在CBD进行的勘探钻孔的CPT和土壤指数测试的结果与循环三轴（CTX）测试结果相结合，以表征在几个建筑工地的土壤沉积物。传统的一维剪切引起的地面沉降程序不捕捉剪切引起的变形机制和地面损失的影响，由于沉积物喷出物。需要改进程序。非线性有效应力分析，使用强大的土壤本构模型校准通过CTX测试提供了一种手段，开发这些程序。对于中密砂和粉质砂，CTX试验估计的循环阻力与基于CPT的方法大致一致;然而，CTX试验提供了有关孔隙水压力响应和应变发展的有用见解。相关性和CTX测试进行松散的干净的沙子表明，这些标本的采样过程中受到干扰。从这个正在进行的研究的中期结果，并提供初步建议，用于评估建筑物的抗震性能与浅基础的场地与可液化土壤。
The 2010–2011 Canterbury earthquake sequence provides an exceptional opportunity to investigate the effects of varying degrees of liquefaction on the built environment. Significant ground settlements and building damage in the Central Business District (CBD) were observed for the Christchurch earthquake. The results of CPTs and soil index tests from exploratory borings performed in the CBD are combined with cyclic triaxial (CTX) test results to characterize the soil deposits at several buildings sites. Conventional one-dimensional liquefaction-induced ground settlement procedures do not capture shear-induced deformation mechanisms and the effects of ground loss due to sediment ejecta. Improved procedures are required. Nonlinear effective stress analyses using robust soil constitutive models calibrated through CTX tests provide a means for developing these procedures. The CTX tests estimate generally consistent cyclic resistances as the CPT-based methods for medium dense sands and silty sands; however, the CTX tests provide useful insights regarding pore water pressure response and strain development. Correlations and CTX tests performed on loose clean sands indicate that these specimens were disturbed by the sampling process. Interim findings from this ongoing study are presented, and preliminary recommendations for evaluating the seismic performance of buildings with shallow foundations at sites with liquefiable soils are provided.