基于欧标的软弱岩地质条件下灌注桩承载能力设计分析

Design analysis on bearing capacity of bored piles under weak rock geological conditions based on Eurocodes

灌注桩是码头结构中广泛采用的桩型,比较适合于岩质较软弱、钙砂含量较多的地质条件。依托国外某项目对该地质条件下灌注桩常用桩基竖向承载力和土体对桩基的水平抗力计算方法进行了分析,并与国内行业标准所规定的设计方法进行了比较。其中与国内行业标准的设计方法主要不同之处在于,欧标设计路径一使用两套系数对结构分别进行校核,而国内行业标准通常只采用一套系数。同时文中对该地区灌注桩设计惯例进行了介绍,为海外工程中类似地质条件下的灌注桩基础设计提供参考依据。

Bored pile is a widely used pile type of jetty structure,it has good suitability for weak rock strata area with a high content of calcareous sand.As per project experience abroad,the calculation methods of vertical bearing capacity of common used bored pile foundation and horizontal resistance of soil to pile foundation under such geological condition have been analyzed and the results have been compared to domestic industry standard results.Moreover,the major difference between Eurocode and domestic industry standard has been discussed which is Eurocode design approach one applies two sets of combination factors to check the structure separately,while domestic industry standard usually applies one set of combination factors.Meanwhile,common practice in specific area has been introduced which can be a reference for the design of bored pile foundation under similar geological conditions.