深部开采微胶囊自修复围岩裂隙试验研究

Study on micro capsule self repair experiment of surrounding rock cracks in deep mining

为了有效防止冒顶片帮、巷道-顶板平衡结构失稳等重大灾害事故,提出采用微胶囊自修复围岩裂隙的研究思路。基于相似定理设计并制备了含有微胶囊的自愈合相似试件,对其进行单轴抗压试验,通过多水平多因素正交试验对试件抗压强度的影响因素进行了研究,通过计算试件强度修复率研究了微胶囊掺量、粒径、养护龄期、养护温度及预压载荷对相似试件自修复性能的影响。试验得出,掺有微胶囊的相似试件的强度修复率的主要影响因素及其影响程度为:微胶囊掺量﹥微胶囊粒径﹥养护龄期;自愈合效果最佳组合是微胶囊掺量0.8%、微胶囊粒径200μm、养护龄期7 d、养护温度40℃。

In order to effectively prevent the roof falling and spalling,the gateway-roof balance structure instability and other major disaster accidents,a study idea with the micro capsules to repair the cracks in the sidewalls of the gateway was provided. Based on a similarity theorem,a self healing similar specimen with the micro capsules was designed and prepared. A uniaxial compressive test was conducted on the self healing similar specimen. With a multi level and multi factor orthogonal test,a study was conducted on the influence factors of the compressive strength for the specimen. With the calculation on the strength repair rate of the specimen,a study was conducted on the mixing amount,partical size,curing period,curing temperature of the micro capsule as well as the preloading affected to the self repair performances of the similar specimen. The test showed that as for the similar specimen with the micro capsules,the major influence factors and the influence degrees of the strength repair rate would be the mixed amount of the micro capsule > partical size of the micro capsule>curing period. The best combination of the self healing effect was the micro capsule with a mixed amount of 0.8%,the micro capsule with a partical size of 200 μm,the curing period of seven days and the curing temperature of 40 ℃.