摘要
饱和砾石土层存在地震液化的可能,但其地震液化判别,目前尚缺乏有效可靠的检测方法和判别标准,国内现行规范明确采用标准贯入临界锤击数法及相对密度法进行砂土液化复判。但由于砾石土中很难进行标准贯入试验,取值难度很大,标准贯入临界锤击数法不适用于砾石土;而水位以下饱和砂砾石层难以获取其天然密度、含水率等指标,相对密度法可操作性亦不强,导致砾石土的液化复判无可靠依据与方法。采用超重型动力触探临界锤击数法判别砾石土土体液化势,并已成功运用于工程实践,对今后类似土体液化判别有很好的参考作用。
There is possibility of seismic liquefaction in saturated gravel soil layer,but there is no effective and reliable detection method and criterion for judging seismic liquefaction at present.Standard penetration critical hammering number method and relative density method are clearly adopted in the current domestic codes to re-judge liquefaction of sand.However,it is difficult to carry out standard penetration test in gravel soil,and it is very difficult to select the value.The standard penetration critical hammer number method is not suitable for gravel soil.However,it is difficult to obtain the natural density,water content and other indicators of saturated gravel layer below water level.Relative density method is not easy to operate,so there is no reliable basis and method for the liquefaction re-evaluation of gravel soil.In this paper,the critical hammering number method of super-heavy dynamic penetration is used to identify liquefaction potential of gravel soil,and it has been successfully applied in engineering practice,which has a good reference value for identifying liquefaction potential of similar soil in the future.
引文
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