Application of grouting technique for stabilization of coarse materials Karkheh storage dam experience, Iran

This paper summarizes results and experiences obtained from stabilization of relatively coarse materials of drain using grouting technique in the Karkheh dam, southwest Iran. The grouting works performed at the Karkheh dam were part of the prerequisites for development of the dam's complementary cut-off wall. Since the dam was completed, the execution of the new cut-off wall from the dam crest was inevitable. Hence, one of the main difficulties associated with the development of the new wall was trenching and execution of plastic concrete wall through relatively coarse materials of the drain in the dam body. A full scale platform consisting actual drain materials was constructed and underwent various tests. Results of the testing program revealed that a Water/Cement mix ratio of 1/(1.5-2) can successfully stabilize the drain materials. After finalizing the technical characteristics of grouting, the method was applied on the drain materials of the Karkheh dam body. The results were satisfactory and the materials were stabilized successfully so that the cut-off wall was executed without any technical problem.