摘要
本文通过某科技大楼深基坑排降水的设计及施工效果,并对花岗岩残积土若干岩土工程问题进行分析和探讨,指出降水是直接影响岩土工程设计与施工的成败关健。
Problems of litho-soil engineering at granite residual soil in fujian costal area are analyzed and discussed in this paper, indicating that lowering of watertable is the key of design and construction of litho-soil engineer- ing, and following view of points are indicated as well:
(1) Weathered crack, structure crack and the degree of their development in the granite weathered aqui-far are strongly influent on the volume and effect of yielding water in a single well. Site and depth of the well of lowering of watertahle is the key of design and it is leas relative to the quantity of the wells. The depth of the well of lowering watertahle must reach at some depth of strongly weathered rock.
(2) Lowering of watertable is not only in favor of construction but also increasing the stability of the slope soil layer and supporting structure. If lowering of watertable is considered in the design of engineering foundation ditch supporting, the manual digging hole pile needn't use, and the spray-anchor supporting is used, thus the time and cost of the projection is greatly saved.
(3) When excavation stress is release, the granite residual soil is easy to be disintegration and demineral-ization and even yielding unfixed sand by absorbing water under the action of underground water and the pressure difference, and this will cause catastrophic falling of ground bearing capacity. Bearing capacity of many manual digging hole piles are not met the demand of design. Therefore using lowering watertable project must be pay more attention in the granite residual soil area.
出处
《福建地震》
2003年第4期37-42,共6页
Fujian Seismology
关键词
花岗岩残积土
降水设计
深基坑开挖
人工挖孔桩
granite residual soil design of lowering watertable excavation of deep foundation ditch manual digging hole pile
