摘要
现行行业标准《建筑桩基技术规范》(JGJ94-2008)[1]采用嵌岩段侧阻和端阻综合系数ζr与基岩单轴抗压强度frk来计算嵌岩桩嵌岩段的总承载力。该方法较简单且工程意义明确,便于工程设计使用。然而规范中综合系数的取值存在一定的局限性。采用ABAQUS通用有限元软件对武汉绿地中心等4个背景工程共20余根现场试桩试验成果进行了数值拟合,取得了较合理的岩(土)参数取值;利用前述参数,建立不同岩性条件下的嵌岩桩数值计算模型,对综合系数进行了计算分析,并建立其与基岩岩性、嵌岩深径比的关系,提出了综合系数建议取值表。相比于规范取值方法,该方法对不同岩石强度分类和嵌岩深径比两个维度上进行了扩充与细化。通过背景工程嵌岩桩试桩承载力的验算表明,采用综合系数比按规范计算的综合系数更接近试桩实测结果。
For the current technical code for building pile foundations(JGJ94-2008), the comprehensive coefficients of shaft/tip resistance for rock socketed pile are used to calculate the bearing capacity of the rock-socketed part. The method is easily to be used and is meaningful for the engineering application, while the values of the comprehensive coefficient are not very reasonable. Based on the data about 20 pile tests of 4 background projects, the FEM is used to calculate the comprehensive coefficient for rock socketed pile. And a value table are presented, which is more detail than the standard table; in which the relationship among comprehensive coefficient, rock property and depth-diameter ratio of rock-socketed pile is given. It is shown that the calculation results of using the comprehensive coefficient proposed herein is more closer to the measured value than the calculation results of using the comprehensive coefficient of the current code.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2015年第S2期289-295,共7页
Rock and Soil Mechanics
基金
国家科技支撑计划课题(No.2012BAJ01B02)
国家科技支撑计划课题(No.2012BAJ07B015)
