强蚀变花岗岩坝基填料改良试验

发布时间：2018-03-03 13:10

本文选题：改良土　切入点：渗透特性　出处：《人民长江》2017年S1期 　论文类型：期刊论文

【摘要】：某抽水蓄能电站工程区存在大量结构松散强蚀变花岗岩,严重影响坝基、隧洞和地下厂房的稳定性,但这些强蚀变花岗岩经过改良则可用于坝基填筑。利用生石灰和水泥2种改良剂对变花岗岩进行改良,对比改良前后强蚀变花岗岩的渗透、压缩和强度随掺灰比、养护龄期等的变化规律,对改良效果进行评价。研究结果表明:掺入生石灰和水泥后,随着掺灰比增加,渗透系数均大幅度递减,压缩模量逐步递增;不同龄期试样的压缩性质也有差异;水泥改良土抗剪强度指标随着掺灰比增大而迅速增长,生石灰改良土的抗剪强度指标在7%掺灰比处存在峰值。最后综合对比分析确定,水泥比生石灰更适合改良强蚀变花岗岩,水泥改良土的最优掺灰比为5%~7%。
[Abstract]:There are a large number of loose and strong altered granite structures in a pumped storage power station area, which seriously affect the stability of dam foundation, tunnel and underground powerhouse. However, these strongly altered granites can be used for dam foundation filling. Two kinds of amendments, quicklime and cement, are used to improve the altered granite, and the permeability, compression and strength of the strongly altered granite are compared with the ratio of cement to cement before and after the improvement. The change rule of curing age and so on, the improvement effect is evaluated. The results show that the permeability coefficient decreases greatly and the compression modulus increases gradually with the increase of the ratio of lime and cement, and the results are as follows: (1) after adding quicklime and cement, the permeability coefficient decreases greatly and the compression modulus increases gradually; The shear strength index of cement modified soil increases rapidly with the increase of cement mixing ratio, and the shear strength index of quicklime modified soil has a peak value at 7% cement ratio. Cement is more suitable for improving strongly altered granite than quicklime, and the optimum mixing ratio of cement to lime is 5 / 7.
【作者单位】：中国电力工程顾问集团华北电力设计院有限公司;河南水利与环境职业学院;中水珠江规划勘测有限公司;华北水利水电大学资源与环境学院;
【分类号】：TV223

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