减沉桩与加筋土褥垫层联合作用减沉机理研究

Study of settlement-reducing mechanism of co-action by settlement-reducing pile and reinforced soil cushion

采用减沉桩和加筋土褥垫层的地基处理方式,能显著减小回填土地基深降,且具有较好经济性。为掌握其联合作用机理,以某多层住宅的复合地基为例,通过布置监测仪器,监测了桩和桩间土的压力及沉降、加筋土褥垫层中土工格栅的变形以及建筑物的沉降。分析了桩和桩间土的应力变化情况、土工格栅变形以及桩与桩间土的沉降差异。结果表明,减沉桩的作用是控制沉降,而加筋土褥垫层的作用则在于提高地基土强度并协调变形;减沉桩在褥垫层方向存在刺入现象。上述机理的清晰阐释,有助于在实际工程中更好发挥该种复合地基的作用,有效控制建筑物沉降。

The foundation treatment technology of settlement - reducing pile together with reinforced soil cushion can efficiently control the settlement of back - filled foundation, which is economic. For better understanding the co - action mechanism of this composite foundation, the monitoring devices were arranged at the foundation of a multistory building, the monitoring program in- eludes the following items ： soil pressure, settlement of piles and the soil among piles, deformation of geogrid in the reinforced soil cushion, settlement of the building. The stress variation laws of pile and the soil among piles are analyzed, and deformation of geogrid and the settlement differences of piles and soil among piles are discussed. The results show that the action of settlement - reducing pile is controlling settlement, and the action of reinforced soil cushion is strengthening soil strength and coordinating de- formation; the penetration phenomenon of pile to soil cushion is existed.