文献类型：期刊文献

英文题名：Composite geopolymer based on copper tailings: Mechanical properties, strength models and microstructure

作者：Wang, Wei[1,3];Wei, Pengfei[1];Jiang, Ping[1];Li, Na[1,3];Chu, Fuyong[2];Fu, Jiajia[1,4];Wang, Xudong[4]

机构：[1]Shaoxing Univ, Sch Civil Engn, Shaoxing 312000, Peoples R China;[2]Wenzhou Polytech, Sch Civil Engn & Architecture, Wenzhou 325035, Peoples R China;[3]Natl Univ Singapore, Dept Civil & Environm Engn, Singapore 117576, Singapore;[4]Nanjing Tech Univ, Sch Transportat Engn, Nanjing 211816, Peoples R China

年份：2025

卷号：13

期号：3

外文期刊名：JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING

收录：SCI-EXPANDED(收录号：WOS:001502085800008)、、EI(收录号：20252218536153)、Scopus(收录号：2-s2.0-105006880626)、WOS

基金：This work was supported by the National Natural Science Foundation of China (Grant No. 52179107) .

语种：英文

外文关键词：Copper tailings; Alkali activation; Strength characteristics; Microstructure; Strength prediction model

外文摘要：Resourceful utilisation of tailings waste remains a hotspot in global research. While silica-aluminate-rich copper tailings can serve as raw materials for geopolymer preparation, their high Si/Al ratio significantly limits the geopolymerization degree. This study investigates the feasibility of developing copper tailings-based geopolymers for road base applications, using copper tailings as the primary raw material supplemented with 30 % soft soil, 15 % fly ash, and 5 % cement. The effect of NaOH content on the strength characteristics of copper tailings-based geopolymers was explored by the unconfined compressive strength test and triaxial test. The mineral composition and microstructure of copper tailings-based geopolymers specimens were characterised based on the microscopic technique. The results show that: (1) With the increase of NaOH content, the unconfined compressive strength of the copper tailings base polymer increases and then decreases, and reach the maximum value when the NaOH content is 1 %. Compared with the sample without NaOH, the addition of 1 % NaOH increased the unconfined compressive strength by 47 % at the early stage and 69 % at 28d curing age. (2) An optimal NaOH content significantly improves the shear performance of the copper tailings-based polymer, primarily by enhancing its cohesion. Triaxial test results demonstrate that 1 % NaOH addition increases cohesion by 73 % at 28d curing age. (3) The NaOH promotes the formation of geopolymer gel, refines the pore structure, and increases sample density, thereby enhancing strength. Overall, the research results can provide a reference for the application of copper tailings solid waste in roadbed materials.