博瓦水电站引水隧洞富水破碎围岩治理加固技术研究

Study on Treatment and Reinforcement Technology of Water-Rich Broken Surrounding Rock in Diversion Tunnel of Bowa Hydropower Station

引水式发电站在建设过程中往往需要开挖很长的引水隧洞,开挖过程中会遇到各种各样的地质条件,极易发生涌水、突泥、坍塌等灾害。为了提升富水破碎围岩的稳定性,文章在传统水泥基注浆材料基础上,掺入氧化石墨烯和粉煤灰,制备了一种环保高性能的富水破碎带治理注浆材料。结果表明:氧化石墨烯具有超大的比表面积和层状海绵结构,能够吸附在粉煤灰周围,促进粉煤灰发生二次水化反应,同时粉煤灰具有良好的填充功能,在两者的协同作用下,促使注浆材料具有更高的强度、抗渗性和抗离子侵蚀性。通过试验确定了氧化石墨烯的最佳掺量为0.03%,粉煤灰的掺量不宜过高,宜控制在10%~20%;复掺氧化石墨烯和粉煤灰的新型注浆材料相比传统水泥基注浆材料,取芯率提升了23%,平均抗压强度提升了38.1%,能够对富水破碎带围岩起到较好的治理加固作用。

In the process of the construction of diversion power station,it is often necessary to dig a very long diversion tunnel.During the process of excavation,various geological conditions will be encountered,which is prone to water gushing,mud outburst,collapse and other disasters.In order to improve the stability of water-rich broken surrounding rock,this paper prepares an environmentally friendly and high-performance grouting material for water-rich broken zone treatment by adding graphene oxide and fly ash on the basis of traditional cement-based grouting materials.The results show that graphene oxide has a large specific surface area and a layered sponge structure,which can be adsorbed around fly ash and promote secondary hydration reaction of fly ash.At the same time,fly ash has a good filling function.Under the synergistic action of the two,the grouting material has higher strength,impermeability and ion erosion resistance.According to the experiment,the optimum content of graphene oxide is 0.03%,and the content of fly ash should not be too high and should be controlled at 10%to 20%.Compared with the traditional cement-based grouting material,the new grouting material mixed with GO and fly ash has a 23%increase in core rate and a 38.1%increase in average compressive strength,which can play a better role in the treatment and reinforcement of surrounding rock in water-rich broken zone.