Experimental study of damage evolution of artificial dam strength of underground reservoir

Water storage technology via underground reservoirs has become a crucial component of water-coal joint mining in ecologically fragile mining area of Western China. Stability is one of the critical factors for the construction of underground reservoirs and its long-term utilization. To investigate the impacts of repeating water absorption and dr- ying,mining and rock burst on the change of strength,the authors took C30 concrete as an example which was used in building artificial dam of underground reservoirs in Daliuta colliery. Strength test via ultrasonic rebound comprehensive method,cyclic loading test and acoustic emission (AE) uniaxial compression test were employed in this study. The re- sults showed that the formula of ultrasonic rebound comprehensive strength could predict the concrete strength under water intrusion. Also,the strength of concrete had a maximum fall by 17% affected by cyclic loading,while the figure for concrete with water intrusion showed a minimum decrease by 26% . The damage evolution characteristics of con- crete specimens subjected to loading were investigated by AE counts. In summary,the authors found the co-effects of cyclic loading (mining and rock burst) and water had a significant impact on the stability of artificial dam of underground reservoirs.