DEVELOPMENT OF SUSTAINABLE ENGINEERED CEMENTITIOUS COMPOSITE (ECC) WITH TERNARY INDUSTRIAL SOLID WASTES AND COST-EFFECTIVE PVA FIBRES

摘要

Engineered Cementitious Composite (ECC) with ductile strain-hardening and fine multiple cracking behaviors has been recognized as a type of advanced and resilient alternative to conventional concrete materials. However, the high cost of the constituents, mainly associated with high cement content and large consumption of expensive polyvinyl alcohol (PVA) fibres, limits the wide application of ECCs. To improve the sustainability and reduce the material cost as well, latest efforts were made by applying green binders with industrial wastes and/or recycled fibres. Herein, this study focuses on the potential use of industrial solid wastes (ISWs) including silica fume (SF), fly ash (FA) and ground granulated blast furnace slag (GGBFS), and low-cost PVA fibres produced by local synthetic fibre factory. Firstly, new matrixes incorporating with ternary industrial solid wastes were designed and optimized through partially substituting cement by successive steps. Then mechanical properties of cost-effective PVA-ECC were experimentally evaluated. Results show that even if as much as 50% of Portland Cement is replaced with ISWs, ECC with local PVA fibres still maintains strain-hardening and multiple cracking behaviors accompanied by a tensile strain capacity up to 1.0%. Such improvement may significantly reduce the environmental impact and material cost, and is expected to greatly promote the field applications of ECC with local ingredients.