Lian, C. J. (Shandong University of Science and Technology) | Hou, J. Z. (Shandong University of Science and Technology) | Gao, G. L. (Taian Taishuo Strata Control Science and Technology Co. Ltd.) | Wang, G. (Taian Taishuo Strata Control Science and Technology Co. Ltd.) | Song, W. T. (Henan Polytechnic University)
ABSTRACT: It has wide distributions and large recoverable reserves of Jurassic period coal seam in China. It is difficult to maintain stability of the development roadways with long service term for Jurassic strata because there are abundant argillaceous rocks and some minerals in the high argillaceous rocks will be expanding while meeting with water. The fractures of the roadways develop well under high stress and are suitable to filling with grouting. But the poor cementing performance of cement with argillaceous rock as well as a heavy water filtration rate of cement slurry had resulted in failures of many engineering cases adopting cement grouting to reinforce this kind of roadways. In this paper, according to characters of the high argillaceous rock in Jurassic strata, a marlaceous inorganic grouting material which possesses the well cementing performance with argillaceous rocks and little filtration rate was introduced; and the grouting reinforcement mechanism, construction technique and engineering application effect about it was clarified. It will be of great significance for reinforcement and maintenance of the development roadways with high argillaceous rocks.
According to statistics, 60% of the proved coal reserves in China distributes in Early-Middle Jurassic period of northern North China, southern Northeast China and Northwest China, along with late Jurassic to early Cretaceous period of Northeast China and east Inner Mongolia. The period of coal forming is short and argillaceous rocks are abundant in Jurassic strata. Moreover, there are quite a few expanded minerals in some strata. So the roadways are easily to be deformed and damaged when affected by mining-induced stress. In addition, this kind of soft rock roadways has an obvious time effect. For the development roadways with long service term, serious deformations are frequently observed and part of the roadways has suffered deformation and maintenance time after time. The stability support of the development roadways really need much cost.