Synergetic–Complementary Use of Industrial Solid Wastes to Prepare High-Performance Rapid Repair Mortar

Abstract

With the vigorous development of infrastructure engineering, there are growing demands for high-performance rapid repair mortar, especially those using environmental-friendly and low-carbon cementitious materials. Hereupon, this work explored an innovative approach for rapid repair mortar preparation using solid waste-based calcium sulfoaluminate cement. The calcium sulfoaluminate cement was first prepared via synergetic–complementary use of industrial solid wastes and then adopted to prepare rapid repair mortar by proportionally mixing with standard sand and four additives (i.e., polycarboxylate superplasticizer, lithium carbonate, boric acid, and latex powder). The mechanistic analysis indicated that the four additives comprehensively optimized the mechanical strengths, fluidity, and setting time of rapid repair mortar by adjusting the hydration process of calcium sulfoaluminate cement. The test results showed that the 2-h compressive and flexural strength, and 1-day bonding strength of the prepared rapid repair mortar were 32.5, 9.2, and 2.01 MPa, respectively, indicating excellent early-age mechanical performance. In addition, the 28-day compressive and flexural strengths of the rapid repair mortar reached 71.8 and 17.7 MPa. Finally, a life cycle assessment and economic analysis indicated that this approach achieved environmental-friendly utilization of industrial solid wastes, and cost-effective and energy-saving natures, which supports current trends towards a circular economy and green sustainable development.

Experimental Study Based on Box–Behnken Design and Response Surface Methodology for Optimization Proportioning of Activated Lithium Slag Composite Cement-Based Cementitious Materials

“…Dong et al [24], Liu et al [25] found that alkali exciters could effectively promote the dissolution and hydration reactions of silicates and aluminates in lithium slag, which in turn improved the volcanic ash activity of lithium slag and help to improve the compressive strength of lithium-slag-cement-based cementitious materials and their durability performance. In addition, Shen et al [26] found that alkaline exciter dosing significantly affected the lithium slag activity. Wu [18] and Wang et al [27] found that high-temperature complex alkali excitation was more effective in improving the activity of lithium slag.…”

Experimental Study of Sulfoaluminate Cement-Based Rapid Repair Mortar Undergoing Hot/Wet Harsh Conditions: Mechanical Strengths, Hydration Products, and Ettringite Evolution Mechanism

“…Meanwhile, the life-cycle assessment results indicated that this approach was environmentally friendly, cost-effective, and resource-efficient. 18 Our previous work comprehensively studied the influence of different additives on the performance of RRM and an obtained optimized preparation method. 19 These studies showed that an SAC-based RRM can achieve excellent mechanical strengths and good workability.…”

“…Li et al successfully prepared RRM with high mechanical strengths using solid WSAC, and the 2 h compressive and flexural strengths and 1-day bonding strength of the prepared RRM reached 32.5, 9.2, and 2.01 MPa, respectively. Meanwhile, the life-cycle assessment results indicated that this approach was environmentally friendly, cost-effective, and resource-efficient . Our previous work comprehensively studied the influence of different additives on the performance of RRM and an obtained optimized preparation method .…”