[提要]  根据沉管扩底灌注桩的理论计算，结合工程实例进行静载试验、沉降观测等试验研究，对沉管扩底灌注桩的技术特点和经济指标做了对比分析，认为沉管扩底灌注桩优于其它桩型，为沉管扩底灌注桩的进一步推广应用提供了依据。
[关键词]  沉管扩底灌注桩 泥浆护壁 桩靴 缩颈

According to the theoretical calculation about the sinking tubular and expanded bottom placing pile and in combination with the engineering examples, the researches such as test with dead load, settlement observation and so on are made. By means of the analyses on technical peculiarity and economic target, authors draw a conclusion that the sinking tubular and expanded bottom placing pile is superior to the others, which provides the basis for further popular use.
Keywords:  sinking tublar and expanded placing pile; grout protected wall; pile shoe; necking