Optimization design and characteristic of retarding and low-early-strength grouting material for capsule grouting technology: laboratory and field evaluation

• DOI: 10.1016/j.jmrt.2022.07.038
• Publication Date: 2022-07-09T04:46:49Z
• Authors: Jianyou Huang; Yu Diao; Pengjin Li; Gang Zheng; Weiqiang Pan; Yiming Su; Wei Gan; Hao Chen
• Keywords: Superplasticizer

Capsule grouting technology (CGT) is developed to control the deformation of underground structures induced by adjacent construction. Meanwhile, multiple necessary for CGT achieve desired effect as heterogeneity and complexity soil. This study proposed a retarding low-early-strength material (RLGM) realize CGT. Response surface methodology (RSM) was applied effects formulation on workability mechanical strength RLGM, then microstructures optimal RLGM were analyzed X-ray diffraction (XRD) scanning electron microscopy (SEM). Moreover, analysis variance (ANOVA) models predict performance RLGM. Results show that different formulations lead significantly contributions performance, each factor shows positive or negative synergistic with others. Etidronic acid retarder (EAR) plays dominant role in initial setting time, correlation between time compressive presents an obvious correlation. Based multi-objective optimization considering multi-performance requirement grouts CGT, optimized mix proportion obtained water-cement ratio 1, bentonite (B) 27.5%, polycarboxylate superplasticizer (PCE) 0.28%, EAR 0.75%. Accordingly, 10 days highly desirable goal, is, 124.1 h 0.2 MPa, respectively. Finally, field trial result confirms good working during