黑龙江省西部地区分散性粘土工程特性及处理措施

本文是根据1980年以来在我省西部地区38个取土点采样试验研究成果撰写的。通过常规土工试验、碎屑试验,双比重计试验、针孔试验、石灰掺量改性试验、反滤试验,其它防治措施与整体模型试验,结合现场调查取得以下主要结论:1.黑龙江省西部地区松嫩平原的某些土属于分散土,它是导致某些工程破坏的主要原因;2.它的分布与苏打碱土分布有一致性;3.它与普通粘土的常规物理力学指标没有特殊差异;4.在分散土中掺入0.5～1％的石灰就可以把分散土转变为非分散土,在工程实践中以掺量3％为宜;5.砂反滤是防止土方工程分散破坏的有效措施;6.加大击实功和控制施工含水量,虽可提高土的抗冲性能,但不能改变分散特性;7.整体模型试验给出了几种典型的、可行的补救措施;8.我省西部地区和其它地方一样,雨水对分散性粘土的冲蚀破坏是主要的,应特别重视。

Behavior of Dispersive Clay and Its Treatment Practice in the West Part of Heilongjang

This paper is based on the result of 38 sample tests of the dispersive clay obtained from the west part of Heilongjang province. By means of the normal physical test, disintegrative test, collapse test, chemical analysis of the proewater, clastic test, two-hydrometer test, pinhole test, lime-stabilizd test, filter test, together with the protective measures of model simulating test and field practice, since 1980, it was carried out the following primary conclusions:1. Some embankments damaged in Song-nen plain west part of Heilongjang province were mainly due to the behaviour of dispersive clay.2. The distribution of dispersive clay was accompanied with the existence of soda saline-alkali soil in Song-nen plain.3. The normal physical properies of dispersive clay showed little difference from the ordinary clay.4. By mixing 0.5- 1 % lime by weight with the dispersive clay, the latter might be transformed into non-dispersive one, 3% by weight would be the optimum in field practice.5. Sand filter was the effective means to prevent embankment from dispersion.6. By increasing compactive effort and/or controling moisture content, the dispersive behaviour would not be improved.7. The model test gives some kinds of remedial means which is typical and feasible.8. Particular attention must be payed to rainfall which is main casue of eroding dispersive clay in the west part of Heilongjang province as well as in other places.