西安建筑科技大学学报(自然科学版)

排水管桩的概念渐渐被工程界熟知,是软基处理的一种新思路.结合排水管桩的特点,推导得出沉桩后桩周土体内的孔压和固结度解答.并根据所得解答,对沉桩后桩周土体内的超孔隙水压力的消散特性进行分析.结果表明:距桩体较近处的超孔隙水直接沿着排水桩排出,而距离桩体较远处的超孔隙水先流向弹性低压区,再转头流向排水桩排出.随着开孔率β的增加,孔压的消散变快.当β超过10-7时,继续增大其值对加快孔压消散的效果不明显.

The concept of drainage pipe pile, which is a new idea of soft foundation treatment, is gradually known by the engineering field. By considering the characteristics of the drainage pipe pile, the solution of pore pressure and consolidation degree in the soil around the pile after pile driving is derived. According to the obtained solution, the dissipation characteristics of excess pore water pressure in the soil around the pile after pile driving are analyzed. The results show that the excess pore water near the pile is directly discharged along the drainage pile, while that far away from the pile first flows to the elastic low-pressure zone, and then turns to the drainage pile.With the increase of opening ratio β, the pore pressure dissipates faster, and when β exceeds 10-7, the increase of the opening ratio has little impact on the dissipation of the excess pore-water pressure.

引言
1 孔压消散模型的建立
2 孔压解析解的推导
3 桩周土孔压消散特性分析
4 结论

图1 排水管桩地基排水固结模型<br/>Fig.1 Drainage consolidation model of drainage pipe pile foundation

图1 排水管桩地基排水固结模型
Fig.1 Drainage consolidation model of drainage pipe pile foundation

图2 排水孔内渗流示意图<br/>Fig.2 Diagram of seepage in drainage hole

图2 排水孔内渗流示意图
Fig.2 Diagram of seepage in drainage hole

图3 排水管桩排布<br/>Fig.3 Installation pattern of the drainage pipe piles

图3 排水管桩排布
Fig.3 Installation pattern of the drainage pipe piles

表1 土体基准参数<br/>Tab.1 Basic parameters of soil

表1 土体基准参数
Tab.1 Basic parameters of soil

表2 透水管桩基准参数<br/>Tab.2 Basic parameters of the permeable pipe pile

表2 透水管桩基准参数
Tab.2 Basic parameters of the permeable pipe pile

图4 不同级数项数下的初始孔压分布<br/>Fig.4 Distribution of the initial excess pore-water pressure for different numbers of the series term

图4 不同级数项数下的初始孔压分布
Fig.4 Distribution of the initial excess pore-water pressure for different numbers of the series term

图5 不同级数项数下的平均固结度<br/>Fig.5 Average degree of consolidation for different numbers of the series term

图5 不同级数项数下的平均固结度
Fig.5 Average degree of consolidation for different numbers of the series term

图6 不同固结时间下的孔压分布曲线<br/>Fig.6 Pore pressure distribution curve under different consolidation time

图6 不同固结时间下的孔压分布曲线
Fig.6 Pore pressure distribution curve under different consolidation time

图7 不同位置处的固结度曲线<br/>Fig.7 Curve of degree of consolidation at different locations of drainage pipe pile

图7 不同位置处的固结度曲线
Fig.7 Curve of degree of consolidation at different locations of drainage pipe pile

图8 不同开口率β下的平均固结度曲线<br/>Fig.8 Curve of average degree of consolidation under different opening ratios

图8 不同开口率β下的平均固结度曲线
Fig.8 Curve of average degree of consolidation under different opening ratios

图9 不同桩距D下的平均固结度曲线<br/>Fig.9 Curve of average degree of consolidation under different pile spacing D

图9 不同桩距D下的平均固结度曲线
Fig.9 Curve of average degree of consolidation under different pile spacing D

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备注

引言

1 孔压消散模型的建立

2 孔压解析解的推导

3 桩周土孔压消散特性分析

4 结论

期刊信息

备注

引言

1 孔压消散模型的建立

2 孔压解析解的推导

3 桩周土孔压消散特性分析

4 结 论

期刊信息

4 结论