水泥石灰复合改良膨胀土试验

南水北调东线穿过的苏北中部地区的开挖渠道和泵站(泗洪站、邳州站和刘老涧二站)都存在膨胀土问题。若泵站地基直接坐落在膨胀土层上,泵站运行过程中可能存在地基土不均匀胀缩变形而引起泵站建筑物破坏问题。在东线存在的更普遍问题是泵站开挖出的膨胀土综合利用问题,如刘老涧二站开挖出8万多m3膨胀土,堆放在现场需要占用宝贵的耕地,而泵站上下游引水渠道的挡土墙后又需要大量符合要求的填土。将开挖废弃的膨胀土改良后作为挡土墙后的填土,是一项综合利用工程,现研究了膨胀土综合改良方法和改良土的力学性质。

Experimental Research on the Stabilized Lime-cement Expansive Soil

The Eastern Route passes through the canals and pumping stations(the Sihong,Pizhou,and second Liulaojian stations) located in the central area of the northern Jiangsu Province,and the expansive soil may occur in these canals and stations.If the foundation of the pumping station is located on the expansive soil,the structure of the pumping station may have a risk to be destroyed during the operation of pumping because of the uneven-distributed expansion and shrinkage of the expansive soil.Another more important engineering problem in the Eastern Route of the South-to-North Water Diversion Project is the use of the excavated expansive soil during the construction of pumping stations and canals.For instance,more than 80,000 cubic-meter expansive soil was excavated at the second Liulaojian Station,and its storage requires a large area of land.On the other hand,the filling soil behind the retaining wall at the upstream and downstream of the diversion canal at the pumping station needs a large amount of applicable soil.The transformation of the excavated expansive soil to the filing soil behind the retaining wall is a project of comprehensive utilization.The paper studies this transformation using the stabilized method and the characteristics of the stabilized soil.