论文部分内容阅读
包裹碎石桩是在碎石桩外包裹一层土工材料制成的一种新型桩体,由于包裹作用,碎石桩的刚度和抗剪强度得到了明显提高。然而,目前有关包裹碎石桩的研究较少,特别是其抗震性能方面。鉴于此,通过开展包裹碎石桩复合地基和碎石桩复合地基振动台模型试验,在考虑不同类型、幅值的地震波作用下,研究两种复合地基的加速度、桩土应力、破坏现象和位移,进而对比分析这两种复合地基的动力响应规律和抗震性能。试验表明:包裹碎石桩桩顶和桩间土水平方向加速度放大系数均约为碎石桩的2倍;相同地震波条件下,包裹碎石桩复合地基的峰值桩-土应力比约为碎石桩复合地基的3倍;与碎石桩复合地基相比,0.9g人工波加载后包裹碎石桩复合地基在较大区域内产生较窄裂缝;包裹碎石桩复合地基产生的总沉降较碎石桩复合地基减小了51%。因此,包裹碎石桩复合地基的抗震性能优于碎石桩复合地基。
The parcel gravel pile is a new type of pile which is made of a layer of geotechnical material wrapped by the gravel pile. Due to the wrapping effect, the rigidity and the shear strength of the gravel pile are obviously improved. However, there are few researches on the parcel pile, especially its seismic performance. In view of this, through the shaking table test of composite foundation with parcel and gravel pile foundation and gravel pile composite foundation, the acceleration, pile-soil stress, failure phenomenon and displacement of two kinds of composite foundations are studied under the action of different types and amplitudes of seismic waves , And then comparative analysis of the dynamic response of these two composite foundations and seismic performance. The tests show that the magnification factor of acceleration in the horizontal direction between the top of the parcel gravel pile and the soil between the piles is about twice that of the gravel pile. Under the same seismic wave conditions, the peak pile-soil stress ratio of the parcel covered with stone column composite foundation is about the gravel Compared with the gravel pile composite foundation, the composite foundation with the gravel pile after 0.9g artificial wave loading has a narrower crack in the larger area. The total settlement caused by the composite foundation with the gravel pile is more broken Stone pile composite foundation reduced by 51%. Therefore, the anti-seismic performance of parcel-gravel pile composite foundation is better than that of gravel pile composite foundation.