可控浆液压力和浓度注浆器研究

Grout Pressure and Density-Controllable Grout Injector——A Study

分析了地下工程围岩裂隙分布规律 ,即靠近巷道轮廓处的裂隙开度和裂隙密度最大 ,随着与巷道轮廓距离增大 ,其开度和密度逐渐减小。据此研制了一种可变注浆孔内压力的新型注浆器。该注浆器的工作原理为 ,水泥浆液沿注浆孔底部向孔口部流动时 ,其经过注浆器外管上的滤水条缝越多 ,浆液失水亦越多 ,其浓度也越高 ,而其压力则越低 ,从而满足了向孔底部小开度裂隙以较高压力注稀浆 ,向孔口部大开度裂隙以较低压力注浓浆的需要。该注浆器可以使孔口压力降低为孔底的 1 7～ 1 8,从而使注浆孔周围浆液扩散半径在孔口部与孔底部基本均衡。通过模拟试验确定了注浆器的主要参数 ,验证了该注浆器改变注浆孔内浆液压力的有效性。

An analysis is made of the distribution laws of crannies in surrounding rocks of underground engineering. It is found that the opening and density of the crannies decrease gradually with the increase of their distances to the laneway's profile and are specially the largest nearby the laneway's profile. Based on this, a new type of hole's grout pressure variable grout injector has been developed. Its operation principle is as follows: when cement grout flows along the grouting hole's bottom to the grouting hole's top, the more the number of filtrating gaps on the grout injector's outer pipes it goes through, the more the quantity of water it losses, so that the higher its density and the lower its pressure, meeting the needs of high pressure grouting of small opening crancies at the hole's bottom and low pressure grouting of large opening crannies at the hole's top. The grout injector can reduce the grouting pressure at the hole's top to 1/7～1/8 of the grouting pressure at the hole's bottom, achieving about the same grouting diameter at the hole's top and bottom. Through its simulation tests, its key technical parameters have been established and its feasibitity to alter the hole's grout pressure has been verified.