粉喷桩-石灰桩联合加固软弱地基试验研究

某工程软土地基由淤泥和淤泥质粘土组成，需对其进行处理，使复合地基承载力达到180 kPa，以满足上部荷载要求。采用粉喷桩、粉喷桩-石灰桩联合加固方法对该地基进行现场加固试验研究，结果证明，粉喷桩-石灰桩联合加固法比单纯采用粉喷桩加固法更节省费用，效果更好。在联合加固法中，先施打粉喷桩，后施打石灰桩的工序比先施打石灰桩后施打粉喷桩的工序能获得更高的复合地基承载力。并对联合加固法的复合地基承载力的计算方法提出了建议。

In-situ test study on soft soil foundation improvement by dry jet mixing piles (DJMP) combined with quicklime piles

A soil foundation composed of silt and silty clay needs to be improved in order to get its bearing capacity of composite foundation reaching 180 kPa. A series of in-situ improvement tests on the foundation were carried out by the methods of dry jet mixing piles (DJMP) combined with quicklime piles and DJMP. The results of the tests indicate that it is cheaper and more efficient by the method of DJMP combined with quicklime piles than the method of DJMP and that the composite foundation is to attain higher bearing capacity by process of DJMP carried out before quicklime pile improvement than DJMP carried out after quicklime pile inprovement. The calculation methods of bearing capacity for composite foundation of DJMP combined with quicklime pile are proposed.