粗砂砾石地层中高压旋喷桩隔水帷幕施工技术

Construction of the jet grout water cut-off curtain in coarse gravel formation

摘要:

太原万达广场A2区商住楼基坑工程部分区域为粗砂砾石地层，基坑隔水帷幕中深层搅拌桩无法有效使用。提出了在粗砂砾石地层采用高压旋喷桩隔水帷幕的施工技术方案，采用双套管锚杆钻机引孔、单管高压喷射工艺进行施工，成功实施了这一工程。经检查，喷射注浆体相互咬合良好，有效桩径内水泥含量均匀无夹块现象，隔水帷幕止水效果良好。

Abstract:

Part of the foundation pit of the Zone A2 commercial and residential buildings of Taiyuan Wanda Plaza is composed of coarse sand and gravel stratum， where the deep mixing piles cannot be used effectively for the water cut-off curtain of the foundation pit； therefor， high pressure jet grouting piles were put forward for the water cut-off curtain in coarse sand and gravel stratum. With the jet grout technology， the double casing anchor drill pre-bored the grout hole with the single pipe high pressure jet grout process for grouting to complete the project successfully. Inspection indicated that the jet grouting elements interlocked well with each other with even cement content across the effective pile diameter and free of blocky inclusions； thus， providing good sealing effect.