Synchronous grouting materials for shield slag insilty clay of Zhengzhou metro(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2020年3期
- Page:
- 53-62
- Research Field:
- 桥梁与隧道工程
- Publishing date:
Info
- Title:
- Synchronous grouting materials for shield slag insilty clay of Zhengzhou metro
- Author(s):
- HAO Tong1; LI Xinxiao1; LENG Faguang2; WANG Shuai1
- (1. School of Civil Engineering, Zhengzhou University, Zhengzhou 450000, Henan, China;2. China Academy of Building Research Co. Ltd., Beijing 100013, China)
- Keywords:
- tunnel engineering; synchronous grouting material; single factor experiment; resource utilization
- PACS:
- -
- DOI:
- -
- Abstract:
- In order to solve the problems of difficult disposition, pollution of the environment, and difficulty in recycling of shielded slag soil excavated during shield construction in the subway section, to realize the resource utilization of the slag solid waste in the shield section, the preparation of new synchronous grouting material by using shield tunneling to excavate slag to replace part of the sand was discussed. The shield excavated by the shield tunnel of Zhengzhou Metro Line 4 was taken as the research object, according to the chemical composition of the slag soil was analyzed by XRD, the shield slag soil content and the waterbinder ratio were selected as the influencing factors to design and adjust the ratio test. According to the test phenomena and results under different conditions, comparative analysis of the influence of subway shield slag content and waterbinder ratio on the working performance and mechanical properties of the material, and the reference rules are consistency, fluidity, loss of consistency over time, fluidity over time indexes such as loss, stratification, bleeding rate, and stone rate were used to evaluate the working performance of the material, and the indicators were 3 d compressive strength, 28 d air environment molding compressive strength, 28 d underwater environment molding compressive strength, and amphibious compression ratio, to evaluate the working performance of the material, and the feasibility of preparing grouting material by shield muck was discussed.The results show that with the increase in the amount of silty claybased shield slag, the working performance of the material such as consistency and fluidity gradually decreased, but when the shield slag is replaced by 60% (mass fraction), the material gradation can be optimized to strengthen the material. In the absence of additives, the compressive strength can reach 1.17 MPa in 3 d and 2.66 MPa in 28 d air environment. At the same time, the shield slag with a large specific surface area improves the problem of low calculus rate and bleeding of traditional grouting materials. The calculus rate can reach more than 96% and the bleeding rate is about 1%. However, the increase in water requirement makes the new synchronous grouting material has a larger water glue than traditional grouting materials, and the reasonable waterbinder ratio is recommended to be about 1.2 to 1.3. In the absence of the reinforcement of the underwater antidispersant, the index of the waterland compression ratio is slightly lower than the performance requirements, and the remaining performance indexes can meet the requirements of the synchronous grouting material performance regulations.It is economical and socially beneficial to use the shield to excavate the dregs for solid waste recycling. The performance of the material can be adjusted in a large range and is feasible. 8 tabs, 15 figs, 25 refs.
Last Update: 2020-06-03