微生物诱导碳酸钙沉积技术治理某地下室渗漏的现场试验

FIELD EXPERIMENT OF MICROBIAL INDUCED CARBONATE PRECIPITATION TECHNOLOGY IN LEAKAGE TREATMENT OF A BASEMENT

产脲酶微生物催化尿素水解,在有钙源的情况下生成碳酸钙晶体,称之为微生物诱导碳酸钙沉积技术(MICP)。MICP技术应用于土木工程是目前学术界的一个研究热点。针对济南某小区地下车库钢筋混凝土外墙渗漏水的情况,应用MICP技术,采取在裂缝墙体迎水面回填土层灌注巴氏芽孢八叠球菌菌液和营养液的方法进行渗漏治理试验。试验结束后进行的注水试验、墙体超声波检测、回填土层地质雷达检测、混凝土取芯观察、裂缝封堵物质的X射线衍射、电镜扫描分析等表明:灌浆4个月后,背水面墙体裂缝处形成一层碳酸钙膜,将裂缝表面覆盖,在降雨时该裂缝位置已无水渗出;迎水面土体变得更加均匀、紧密,延缓了雨水的渗入;墙体裂缝中有大量的碳酸钙生成,填充效果在墙体的较低位置更为明显。MICP技术为混凝土裂缝修复和地下结构渗漏治理提供了一个新的途径。

Microbial induced carbonate precipitation （MICP）, which use microbial catalyzed hydrolysis of urea and to produce calcium carbonate crystals , is tested to treat the leakage of basement external wall in Jinan .S.pasteurii and reactant are injected into the backfill of the crack wall in the upstream face in-situ.After grouting , the results of permeability field test , ultrasonic measurement , ground penetrating radar detection , concrete coring observation , XRD analysis and SEM analysis show that a CaCO 3 layer forms in the backstream face of the cracked wall and cover the surface of the crack after four months , there is no water leakage in the basement when subjected to raining; the treated soil becomes denser and more uniform;there is lots of CaCO 3 precipitation in the crack and the filling effect is more obvious in the lower part of the cracked wall .The MICP technology provides a new solution to repair the concrete cracks and control the leakage of underground structures .