速凝浆液抗分散性质与凝胶性能试验研究

 为了科学评价注浆浆液的抗分散性质与凝胶性能，设计速凝浆液抗分散性质试验装置，能够模拟浆液在未凝胶之前即受到动水冲刷的关键过程。利用该装置开展水泥水玻璃浆液与改性聚氨酯浆液的抗分散性质试验，并定义浆液留存率指标，对速凝浆液在动水条件下的抗分散性质进行定量评价。试验表明：水泥水玻璃浆液在较小动水流速条件下抗分散性能较好，随着动水流速的增大，浆液留存率迅速减小，其抗分散性质还受到水灰比、水泥浆与水玻璃体积比等因素的影响；改性聚氨酯浆液在较大动水流速条件下仍具有较高的浆液留存率，较水泥水玻璃浆液具有更为优良的抗分散性质和凝胶性能。根据速凝浆液抗分散性质与凝胶性能的试验分析结果，提出突水灾害治理注浆浆液的选择原则与综合治理措施。

EXPERIMENTAL STUDY OF ANTI-WASHOUT PROPERTY AND GELLING PERFORMANCE OF FAST-GELLING GROUT

Grouting technique is widely used to control the water inrush hazards and increase the strength in tunneling and underground engineering. Therefore，the anti-washout property of grout under the flowing water condition is the key factor that determines the grouting effect. In order to evaluate the anti-washout property and the gelling performance of the fast-gelling grout，a specific test apparatus was designed to simulate the vital process of the grout being flushed by the flowing water before gelled. With this device，a series tests were carried out by controlling the velocity of water flow and the mixing proportion of grout. The grout retention ratio(GRR) index was proposed to evaluate the anti-washout property quantitatively. The test results showed that the grout of cement-sodium silicate achieved a large grout retention ratio when the water flow velocity was small，however，the grout retention ratio decreased significantly with the increasing of the velocity of water flow. The GRR of the grout of cement-sodium silicate was influenced by the mass ratio of water to cement and the volume ratio of cement to sodium silicate of the grout. The modified polyurethane grout had a larger GRR under the fast water flow condition and the gel was more compact，which meant that the modified polyurethane grout had the better anti-washout property and the gelling performance. According to the different anti-washout property and gelling performance of grout，a method of choosing grout materials reasonably to dealing with the water inrush was proposed.