膨胀岩地区盾构壁后纤维注浆材料试验研究  

Research on mechanical effect of backfill fiber grouting material on expansive rock

作　　者：张世荣[1] 侯凯文[2] 潘鑫[2] 苏建[2] 欧孝夺[2] 

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055 [2]广西大学土木建筑工程学院,广西南宁530004

出　　处：《广西大学学报（自然科学版）》2016年第1期187-195,共9页Journal of Guangxi University（Natural Science Edition）

基　　金：国家自然科学基金资助项目(51168004)

摘　　要：为研究膨胀岩地区纤维注浆材料与膨胀岩相互作用的规律,以南宁轨道交通一号线穿越膨胀岩区域为依托背景,开展纤维壁后注浆材料力学性能研究,选取3组工程常用配比,分别掺入0.9 kg/m3、1.5 kg/m3、2.0 kg/m3聚丙烯纤维,进行抗压、劈裂抗拉、抗折试验。并自行设计模型试验装置,就掺入1.5 kg/m3纤维时注浆材料与膨胀岩相互作用开展模型试验及数值分析。试验结果表明:(1)与普通注浆材料相比较,纤维对注浆材料的强度影响较小,对其韧性增强作用明显,掺量1.5 kg/m3时,增韧效果最明显,相比普通试块,纤维掺量1.5 kg/m3及以上时挠度增加均在30%以上;(2)相对于普通浆液,相同条件下,纤维浆液使膨胀力衰减32%;(3)当膨胀力增至160 k Pa时,纤维浆液使管片最大正弯矩和最大负弯矩分别减小31.6%和24.2%,可见纤维注浆材料能有效减小膨胀岩膨胀变形对盾构管片的影响。In order to study the interaction between fiber grouting material and expansive rock,the swelling rock region of Nanning Rail Transit Line 1 was taken as the research object. Compressive strength,splitting tensile strength and flexural tests were carried out on three samples of backfill fiber grouting material with different polypropylene fiber mixed ratios of 0. 9 kg / m^3,1. 5 kg /m^3and2. 0 kg / m^3 for mechanical properties research. A model test of the swelling rock and grouting materials was conducted by a self-designed test apparatus,and a numerical analysis was carried out,as well. The experimental results show that polypropylene fiber has little effect on the strength of grouting material while the effect of toughness enhancement is obvious. When the mixed ratio is1. 5 kg / m^3,the toughening effect is obvious. The deflection increases 30% more than that of ordinary slurry,when the mixed ratio is 1. 5 kg / m^3 and above. Compared to ordinary slurry,32% of the expansion force can be reduced by fiber slurry under the same conditions. The maximum positive moment and the minimum negative moment of the segment can be reduced by 31. 6% and 24. 2%,respectively,when the expansion force comes to 160 k Pa. Therefore,fiber grouting materials can effectively reduce the influence of expansion due to rock deformation on shield lining segments.

关 键 词：膨胀岩 盾构壁后注浆 纤维浆液 数值模拟 

分 类 号：TU45[建筑科学—岩土工程]