单玉川    应义淼       （浙江工业大学建筑设计研究院  杭州 310014）

[提要]  在工程设计实践中，长桩持力层下面常遇到软弱下卧层，为了保证所设计的长桩安全有效，关键是软弱下卧层土的沉降量的计算，而按规范JGJ94-94方法计算往往偏大。采用文中根据多年工程实践提出的沉降计算方法进行沉降计算，结果与实际沉降较吻合，较好地解决了此类问题。
[关键词]  长桩  软土下卧层  地基沉降

In engineering design practice, the undersurface of load bearing layer loaded by the long pile often meets with soft soil underlayer. For the purpose of long pile designed to be secure and effective, the settlement calculation of soft soil underlayer is key factor. But it is much large calculated with JGJ94-94 code.The settlement calculaion method presented based on engineering practice of many years is tallied with practiced settlement, and solves analogic questions well.
Keywords:  long pile; soft soil underlayer; foundation settlement