复杂地质条件下的人工挖孔桩施工技术.doc

复杂地质条件下的人工挖孔桩施工技术

　　摘要：　在人工挖孔桩施工中，遇到淤泥、流砂层较厚，地下水极为丰富时，很容易涌砂塌孔，施工进度缓慢或根本无法成孔。本文主要介绍了在复杂地质条件下的人工挖孔桩施工技术成功的经验，可供类似工程借鉴。
　　关键词：　人工 挖孔桩 施工 技术
1 工程概况
　　茂名热电厂5# 机冷却水塔淋水面积达5500m2，高度达到120m，外型呈双曲线形的特种结构。冷却水塔的环基基础位于淤泥、冲质粉质粘土（砂层）及砾砂岩层，设计采用44根φ2000mm的人工挖孔桩来支持冷却水塔的上部结构，单桩深度在8.5m～16.5m之间，桩底要求进入微风化岩层2000mm。
2 人工挖孔桩施工技术方案的选择[1]
　　根据冷却水塔区域的地质报告和试桩情况综合研究分析，44根人工挖孔桩中，约有一半左右位于淤泥、流砂
Under complicated geological conditions of manual digging Piles

Abstract: Dig a Hole in the manual, the encounter mud, sand flow thick, rich groundwater, it is easy to Bay sand hole collapse, construction progress is slow or not at all into the hole. This paper describes the complex geological conditions of artificial dig pile technical success of the experience for similar projects.
Keywords: Artificial Hole Piles
1 Project Overview
Maoming Thermal Power Plant Unit 5 cooling tower water spray area of 5500m2, height to 120m, is in the shape of special structure of the hyperbolic shape. Cooling towers in the mud ring and the foundation, red silty clay (sand) and gravel sandstone, designed with 44 φ2000mm of manual digging pile to support the upper structure of the cooling towers, pile depth of 8.5m ~ 16.5m between the pile and went to the breeze of rock 2000mm.
2 Drilled Piles of artificial selection programs [1]
According to the cooling towers to the geological report and comprehensive study of test piles, 44 piles of artificial excavation, about half in the mud, quicksand