徐州沛县某矿煤矸石工程地质特性试验及地基稳定性分析

近年来,煤矿区用煤矸石回填、碾压后作为建筑地基基础得到了广泛的应用。以徐州沛县某矿煤矸石新鲜样品和回填多年的矸石(1#、2#)样品为例,对煤矸石的颗粒组成、矿物成份及其胀缩性进行分析,结果发现:新鲜矸石颗粒在10mm以上的含量较大,而1#、2#矸石颗粒级配在10mm以下的含量相对较大;煤矸石岩性成份主要为砂岩和泥岩,矸石样品中的粘土矿物有高岭石、绿泥石、伊利石、伊蒙混层和蒙脱石等,新鲜煤矸石中I/M混层和伊利石的含量与1#、2#矸石相比明显高出许多,因而具有较大的膨胀性;1#、2#矸石膨胀性很小,但是在遇水情况下仍具有一定的膨胀性。对煤矸石地基的破坏机理及作用过程进行了分析,并提出用矸石作地基基础时应注意的问题,认为采取适当的措施煤矸石回填地基作为建筑地基是安全可行的。

Coal Gangue Engineering Geological Characteristic Test and Foundation Stability Analysis in a Peixian Coalmine,Xuzhou

In recent years, coal gangue has been widely used for backfilling, building groundwork and foundation after crushed down.Taking a fresh gangue sample from a Peixian coalmine in Xuzhou and aging backfilling gangue samples（1^#、2^#） as example, analyzed their grain composition, mineral components, swell-shrink characteristics. The result has shown that the proportion of grain size 10mm in fresh gangue is in the majority, while in samples 1^#、2^#10mm in the majority. Lithology of coal gangue is mainly sandstone and mudstone; clay minerals in gangue samples have kaolinite, chlorite, illite, illite/montmorillonite mixed layer and montmorillonite etc. In fresh gangue, content of I/M mixed layer and illite is obviously much higher than in samples 1^#、2^#, thus larger expansibility than samples 1^#、2^#, but the later still have certain expansibility under the condition of wet with water. Gangue foundation failure mechanism and process have been analyzed, issues should be noticed when taking gangue as groundwork and foundation put forward, considered that after taking proper measures, coal gangue backfilled groundwork as foundation ground is safe and feasible.