[提要]  以实际工程为背景，详细阐述了疏桩基础的设计计算方法，与普通桩基方案进行了对比分析，重点介绍了疏桩基础上基底宽度的确定、用桩数量的优化、桩土荷载分担比的选择、建筑物沉降量的影响因素和有效控制手段，并与工程的实测结果进行了对比分析，研究结果和实测数据可供参考。
[关键词]  疏桩基础  桩土荷载分担比  沉降控制  回填土

The sparse pile foundation is designed with smaller pile diameter and less pile amount than the conventional pile foundations and therefore costs less. The design procedure of a sparse pile foundation is depicted in details and some related problems are discussed. Analysis results show that the soil properties have great effects on bearing proportion between pile and soil,and the settlement of building is more sensitive to the length of pile and backfill soils.
Keywords:  sparse pile foundation; bearing ratio; settlement control; backfill soils

    　参  考  文  献
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