Research On Chemical Grouting Pressure To The Cracks On Mass Concrete

The chemical grouting repair technology has been widely used in reinforcingconcrete cracks; especially for massive concrete which is of high cost and greatlyaffects the society as engineering structure that benefits the national economy andpeople’s livelihood. Therefore, it is not only social benefits but also economical benefitsto repair and reinforce the cracks by grouting it timely, effectively, reasonably.Based on concrete fracture mechanics theory, the follow text combine the mainused chemical grouting repair technology, reasonably establish analysis and calculationmodel, and confirm the maximum allowed grouting pressure in multiple grouting modes.Afterwards, based on engineering fluid mechanics, study the flowing of grouting fillingin concrete cracks, establish simple model, obtain the simple and practical diffusionradius of grouting filling in concrete cracks. They are quite important basis to makechemical grouting repair plan for concrete cracks. The research result indicates:①Close grouting method. According to grouting nozzle position and air-vent incrack surface, the grouting pressure to crack surface will be evenly or polynomiallinearly.②For repair with drilling method, the grouting pressure to crack surfaceapproximates to evenly.③According to the high similarity between academic maximum allowed groutingpressure by concrete fracture mechanic theory and the actual maximum allowedgrouting pressure, for some special concrete structure, the grouting pressure willincrease as the increase of crack length or depth; for the crack, its size will increase asthe increase of concrete structure width.④Compare all factors, crack width is the most sensitive one to affect fillingdiffusibility.