Properties of structural concrete with high-strength cement mixes containing waste paper sludge ash

Abstract

This paper studies the use of wastepaper sludge ash (WPSA) for structural concrete in binary and ternary mixes with high-strength cement and two industrial by-products, ground granulated blast-furnace slag (GGBS) and pulverised fuel ash (PFA). The potential use of WPSA in this type of concrete and its combination with other supplementary cementitious materials has not been established; thus, further research is needed prior to industrial-scale applications. A series of tests investigated the soundness and setting times of the resulting cements, the fresh concrete workability, cube compressive strength at various curing times, tensile splitting strength, flexural strength, static modulus of elasticity, water absorption and carbonation of the resulting concrete. Good binary WPSA mixes were achieved with high early strength gains, but workability reduced; binary mixes with 15% WPSA, were overall the best in terms of strength and durability, whilst maintaining pumpability. An improvement in the carbonation resistance of ternary GGBS and PFA mixes was also indicated upon addition of WPSA although their strengths were lower than those of binary WPSA mixes. Further mix optimisation can lead to other robust and durable high-strength cement systems with WPSA, allowing for higher cement replacements in structural concrete, for improved environmental impact.

Evaluation of Flexural Strength of Novel Hypo Sludge for Increasing the Strength of M30 Grade of Concrete by Partial Replacement for Cement and Addition of Sikacrete with Conventional Concrete

“…This, in turn, can impact the lifespan of the structure and potentially increase maintenance and repair costs over time. (Mavroulidou, Feruku, and Boulouki 2022).…”

“…It is moldable, versatile, and fire-resistant material [4,5]. More than any other material currently on the market, satisfies practically any conceivable set of performance standards, which has led to its enormous popularity as a building supplement [6][7][8][9]. Reality, More than one cubic meter of concrete, or 10 billion tons, are produced year.…”

Performance Characterization and Evaluation of Innovative Cement Mortars and Concretes Made with Recycled EPS

“…Numerous studies and experiments have focused on the use of sustainable raw materials, particularly the valorization and reuse of waste materials in the production of mortars and cements. This approach aims to optimize the properties of construction materials, especially mechanical and thermal ones, while reducing the extraction and use of raw materials and minimizing landfill waste disposal [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43]. In various studies, waste products, such as fly ash (FA) [28,32], plastic waste [33], green pozzolan (GP) [34], waste paper sludge ash (WPSA) [35], food waste [36,40], and wood biomass ash (WBA-wood bottom ash) from power plants [38,39] have been added to concrete or mortar mixes.…”

“…This approach aims to optimize the properties of construction materials, especially mechanical and thermal ones, while reducing the extraction and use of raw materials and minimizing landfill waste disposal [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43]. In various studies, waste products, such as fly ash (FA) [28,32], plastic waste [33], green pozzolan (GP) [34], waste paper sludge ash (WPSA) [35], food waste [36,40], and wood biomass ash (WBA-wood bottom ash) from power plants [38,39] have been added to concrete or mortar mixes. The use of EPS and recycled expanded polystyrene (R-EPS), as a replacement for aggregate in concrete and mortar formulations, has been extensively experimented with, successfully achieving lightweight and thermally efficient mortars.…”

Investigating the Feasibility of Using Concrete Containing Waste Paper Sludge Ash and Pozzolanic Materials to Repair Bridge Stub Columns

“…Te review of studies about waste paper sludge ash [24][25][26][27][28][29] shows that these materials can be used as a partial replacement for cement. Although waste paper sludge ash can improve the durability properties of concrete, it has little efect on improving the mechanical properties of concrete.…”