Hardpan

As the properties of upper Tertiary strata at this engineering area are closer to those of soil,which can be named special hard soil or soft rock-hard soil,so it is reasonable to be estimated by the methods of soil mechnics.

根据基坑开挖后进行的大量试验研究工作,对上第三系地层的工程地质分类进行了探讨,分析认为:将岩性与成岩作用结合起来对该类地层进行综合分类具有较好的适用性,工程区上第三系地层更多具有土的工程地质特性,可称为特殊硬土或软岩—硬土,以土力学的方法进行评价为宜。