Roles of Waste Glass and the Effect of Process Parameters on the Properties of Sustainable Cement and Geopolymer Concrete-A State-of-the-Art Review

Abstract

Recent research has revealed the promising potential of using waste glass (WG) as a binder or inert filler in cement and geopolymer concrete to deliver economic and environmental benefits to the construction sector. However, the outcomes obtained by different research groups are scattered and difficult to compare directly because of isolated process parameters. In this study, the roles and impacts of WG and process parameters on the performance of WG-added cement and geopolymer concrete are critically reviewed. This study reveals that the chemical and mineralogical composition, and particle size of WG, mix proportion, activation, and curing condition of concrete are the most important parameters that affect the dissolution behavior of WG and chemical reactivity between WG and other elements in concrete; consequently, these show impacts on properties of concrete and optimum WG level for various applications. These parameters are required to be optimized based on the guidelines for high pozzolanicity and less alkali-silica reactivity of WG in concrete. This review provides a critical discussion and guidelines on these parameters and the chemistry of WG in cement and geopolymer concrete for best practice and highlights the current challenges with future research directions.

Keywords: cement; concrete; geopolymer; pozzolanic reactivity; sustainability; waste glass.

Figure 1

WG powder derived from waste glasses [43].

Figure 2

X-ray diffraction pattern for glass powder (windshield glass) (reformatted from [10]).

Figure 3

Strength activity index of WG powder with varying fineness [52].

Figure 4

Selection guidelines and the optimum mixing parameters of WG to develop high-performance concrete [4].

Figure 5

Degree of hydration in cement pastes with various amounts of WG powder [62].

Figure 6

Heat flow during hydration of different binders [63].

Figure 7

Slump values of concrete with WG powder (particle size ≤ 15 µm) [27].

Figure 8

Density and porosity of WG powder-based concretes. (a) The density of concrete with WG powder (particle size < 100 µm) [75]. (b) The porosity of concrete with WG powder (Particle size 8–110 µm) [58].

Figure 9

Chemical mapping of the surface in an ultra-high performance concrete (specimen showing the different anhydrous and hydrous phases) (a) without WG; (b) with 30% WG (12 µm particles) replacing cement [76].

Figure 10

SEM images of the cementitious paste containing WG powder at different ages (a) 80 °C at 1 day; (b) Microwave curing at 1 day; (c) Normal curing at 28 days; (d) 80 °C steam curing at 28 days [77].

Figure 11

The variation in the strength of concrete with WG as SCM. (a) Compressive strength of concrete with WG powder (Particles < 75 µm) in replacement of cement [36]. (b) Compressive strength of WGC with WG powder (particles < 120 µm) as SCM [57]. (c) Splitting tensile strength of concrete with varying content of WG (Particles < 100 µm for cement replacement) and curing periods [75]. (d) Flexural strength of concrete with WG (Particles < 100 µm for cement replacement) [75].

Figure 12

Advantages, challenges, and knowledge gaps of using WG as SCM.

Figure 13

Microstructure and ITZ of mortar with WG aggregates [90]. (a) WG particle mean diameter of 204 µm. (b) WG particle mean diameter 28.3 µm.

Figure 14

Compressive strength of concrete with WG aggregates (particle size 0.8–5 mm) in the replacement of sand [84].

Figure 15

ASR expansion of WG concrete. (a) Expansion of mortar bars with WG (particle size: 0.6–2.36 mm) [51]; (b) variation in the ASR expansion with mean WG powder particle size [38]; (c) relative ASR expansion with varying glass content, color, and concrete grades [102].

Figure 15

ASR expansion of WG concrete. (a) Expansion of mortar bars with WG (particle size: 0.6–2.36 mm) [51]; (b) variation in the ASR expansion with mean WG powder particle size [38]; (c) relative ASR expansion with varying glass content, color, and concrete grades [102].

Figure 16

Performance and optimum replacement level of WG in cement concrete according to particle size and role [4].

Figure 17

Different reaction product formations after alkali activation and geopolymerization of WG and other typical precursors.

Figure 18

Si and Al dissolution from WG powder and fly ash [64].

Figure 19

Hydration characteristics of WG powder-based geopolymer concrete. (a) Heat flow rate of WG powder-based geopolymer concretes [64] (b) Setting time variation in WG powder-based geopolymer concretes [67].

Figure 20

The slump of geopolymer concretes with varying WG powder (fineness = 2009 cm²/g) and activator content [67] (L/s—liquid to solid ratio; WG = 0–20%).

Figure 21

SEM micrographs (1000×; 10 μm) of WG/MK-based geopolymers cured at (a) 25, (b) 40, (c) 60, and (d) 80 °C. Red circles in (a–d) are magnified (3300×; 10 μm) into (e–h), respectively [118].

Figure 22

Effect of WG powder precursor on the compressive strength of geopolymer [118].

Figure 23

Flexural strength of geopolymer concrete with WG (particles size ≤ 60 µm) compared to the fly ash precursors [131].

Figure 24

Different roles of WG and the impacts of different parameters on the performance of geopolymer concrete [4]. (a) Reactivity and roles of WG in geopolymer concrete; (b) Crucial process parameters in alkali activation and geopolymerization with WG.

Figure 25

Density of geopolymer concretes with different aggregates at different ages [35].

Figure 26

Effect of WG (particle size < 45 µm) solution as an activator in fly ash-based geopolymer concretes [130].

Figure 27

ASR expansion in alkali-activated geopolymer concretes with WG powder (particle size < 32.86 µm) [49].

Figure 28

Current research gaps and future research questions in the production, chemistry, and performance of WG-based geopolymer concrete.