张清华¹， 杨益洪¹， 何雪莲¹， 翁丽娅²
（1 温州市建筑设计研究院，温州 325003； 2 温州市勘察测绘研究院，温州 325027）
   
[摘要] 结合实际工程，对嵌入卵石层钻孔灌注桩后压浆设计、施工中后压浆方法的选择、注浆量的确定、后压浆桩的承载力计算、后压浆在超长桩中的应用等进行了研究。试验结果表明，采用后压浆时应选用桩底注浆，桩底后压浆的注浆量与桩径的平方成正比；后压浆桩端承载力可按预制桩的桩端承载力进行计算；后压浆对超长桩的承载力和沉降均有较大改善。
[关键词] 卵石层；钻孔灌注桩；后压浆；注浆量；超长桩

Some problems about post-grouting design of bored pile inserted to boulder bed in soft foundation
Zhang Qinghua¹, Yang Yihong¹, He Xuelian¹, Weng Liya²
(1 Wenzhou Architectural Design and Research histitute, Wenzhou 325003, China;  2 Wenzhou Geotechnical Investigation and Mapping Institute, Wenzhou 325027, China)
   
Abstract: Based on actual projects, it carries out research on the choice of post-grouting method, grouting quantity and bearing capacity of bored pile, and the application of post-grouting in superlong pile. The experiments show that grouting under the bottom of the pile is preferred when using post-grouting, and the grouting quantity is in direct proportion to square of the diameter of the pile. The carrying capacity of the bottom of the post-grouting can be calculated according to the carrying capacity of the bottom of the prefab pile, and post-grouting can geatly improve the carrying capacity and settlement of the super-long pile.
Keywords: boulder bed; bored pile; post-grouting;  grouting quantity;  super-long pile