天津地区标准贯入试验在液化判别中的简化应用

在采用标准贯入试验法进行粉土及砂土的液化判别过程中,根据天津地区实际地质及规范规定的条件下,可以最不利条件确定不同深度处的液化判定标贯击数临界值,然后在外业施工过程中,根据实测标贯击数大于最不利条件下的临界标贯击数时,可直接判定该标贯点粉土或砂土不液化,而不需取扰动土样进行室内颗粒分析试验,这样既满足规范的判定要求,减少室内试验的工作量,同时又能节约勘察成本,是值得采用的一种方法。

Simplified Application of Standard Penetration Test in Seismic Liquefaction Evaluation in Tianjin Region

Based on the engineering geological features in Tianjin and the related standards,the critical standard penetration test value for seismic liquefaction evaluation is defined by depth under the most disadvantageous conditions.Thus,the actual standard penetration test value can be directly used to assess the liquefaction potential of silt and sand in the field without the result of grain size analysis from laboratory test,when the number of blows of standard penetration actually measured are more than those under the most disadvantageous condition.The simplified application can not only satisfy the demand of the relevant standards and but also reduce laboratory test quantity and the investigation cost.So,it is worthy to be recommended.