(中国建筑西南勘察设计研究院有限公司,成都 610059)

摘要: 软岩地基承载力是超高层建筑基础设计关键参数.在现场地质调查的基础上,结合岩石现场和室内试验结果,总结了经验查表法、单轴抗压强度折减法、载荷试验和 Bell 法确定软岩地基承载力的使用条件,并运用上述方法研究某超高层建筑软岩地基承载力取值.结果表明:单轴抗压强度折减法中折减系数 ψr 取值范围大,导致相同岩石地基承载力差异可达 2.5 倍,即便采用地方经验,地基承载力的极差也达 27%;Bell 法计算的地基极限承载力处于载荷试验结果的最小、最大值之间,结果准确性较高,且计算所需要的参数容易获取,当安全系数取 3.5 时,计算结果能充分反映软岩实际承载性能,在未进行载荷试验的场地可采用此方法计算地基承载力.

关键词: 超高层建筑;软岩地基;地基承载力;载荷试验;Bell 法

中图分类号: TU471+.6 文献标志码:A 文章编号:1002-848X(2022)17-0145-04

DOI:10.19701 / j.jzjg.20201423

Research on value of bearing capacity of soft rock foundation for super high-rise buildingin Chongqing area

LIU Haijun,WANG Xin,LIU Xingguo,DING Xiquan

(China Southwest Geotechnical Investigation & Design Insitute Co. ,Ltd. ,Chengdu 610059,China)

Abstract: Bearing capacity of soft rock foundation is the key parameter in foundation design of super high-rise building. Onthe basis of field geological survey,combined with the rock field and indoor test results,the use conditions of bearingcapacity of soft rock foundation by empirical look-up table method,uniaxial compressive strength reduction method,loadtest and Bell method were summarized,and the above methods were used to study value of the bearing capacity of soft rockfoundation for a super high-rise building. The results show that the value range of reduction coefficient ψrin uniaxialcompressive strength reduction method is wide,which leads to a 2.5 times difference in the bearing capacity of same rocks,even if local experience is used,the extreme difference of foundation bearing capacity is at 27%. The ultimate bearingcapacity of the foundation calculated by the Bell method is between the minimum and maximum values of the results of theload test method,the result is more accurate,and the values of the parameters required for the calculation are easy toobtain. When the safety coefficient is 3.5,the calculation results can fully reflect the actual bearing performance of softrock,this method can be used to calculate the bearing capacity of foundation in the site where the load test has not beencarried out .

Keywords:super high-rise building;soft rock foundation;foundation bearing capacity;load test;Bell method

第一作者:刘海军,硕士,高级工程师,注册土木工程师(岩土),主要从事技术管理和岩土工程科研,Email: 1069059102@ qq.com.

[引用本文] 刘海军,王新,刘兴国,等. 重庆地区超高层建筑软岩地基承载力取值研究[ J]. 建筑结构,2022,52(17):145-148. LIU Haijun,WANG Xin,LIU Xingguo,et al. Research on value of bearing capacity of soft rock foundationfor super high-rise building in Chongqing area[J]. Building Structure,2022,52(17):145-148.