摘要
客土喷播复绿高陡裸岩坡面时喷播土体易于剥落,在裸岩表面喷覆微生物砂浆具有提高喷播土体与岩面附着力和稳定性的应用潜力。为此,开展微生物砂浆胶结石灰岩界面剪切试验,研究微生物砂浆与岩石界面的剪切强度变化规律和胶结作用机理。结果表明,胶结后的微生物砂浆-岩石界面的黏聚力和摩擦角分别可达到45.6 kPa和26.40°,微生物矿化胶结对界面的摩擦角影响不大。微生物砂浆的崩解率与碳酸钙生成量呈负指数幂相关,当碳酸钙生成量高于2.5%时,微生物砂浆具有较好的水稳定性。岩面上覆微生物砂浆中具有丰富的孔隙结构,界面剪切破坏主要是砂颗粒与碳酸钙结晶体的接触面剥离,以及碳酸钙结晶集合体内部断裂。研究结果可为微生物岩土技术应用于岩质边坡的生态防护工程提供参考。
The soil is easy to peel off when the external-soil spray seeding(ESSS)technology is used to restore the high and steep bare rock slope.The application of microbial mineralization technology to form microbial mortar on bare rock surface has the potential to improve the adhesion and stability of sprayed soil substrate and rock surface.The interfacial shear tests on the limestone cemented by microbial mortar are carried out to investigate the change of shear strength and cementation mechanism of the interface between microbial mortar and rock.The results show that the cohesion and friction angle of the microbial mortar-rock interface can reach 45.6 kPa and 26.40°,respectively.The microbial cementation has few effects on the friction angle of the interface.When the calcium carbonate content is higher than 2.5%,the microbial mortar has better water stability.There are abundant pore in the microbial mortar overlying the rock surface.The shear failure of interface is mainly caused by the peeling of the contact surface between the sand particles and the calcium carbonate crystals,and the internal fracture of the calcium carbonate crystal aggregate.The research results can provide reference for the application of microbial geotechnical technology in the ecological protection of rock slopes.
作者
邵光辉
孔祥泰
陈海涛
黄容聘
狄志强
刘鹏
SHAO Guanghui;KONG Xiangtai;CHEN Haitao;HUANG Rongpin;DI Zhiqiang;LIU Peng(College of Civil Engineering,Nanjing Forestry University,Nanjing 210049,China;Anhui Construction Engineering Group Co.,Ltd.,Hefei 230000,China;Jiangsu Chenghui Engineering Technology Co.,Ltd.,Nanjing 210037,China)
出处
《岩土工程学报》
北大核心
2025年第6期1142-1151,共10页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金项目(51578293,51809139)。
关键词
微生物岩土
岩质坡面
剪切强度
界面
胶结特性
biogeotechnics
rock slope
shear strength
interface
cementation characteristic
