INTERACTIONS OF WASTE GLASS CULLET IN SIMULATED CEMENT PORE FLUID

Waste glass cullet, which is not melted to make new glass, has found a new use in concrete. There is a potential source of 1.2 Mt for such cullet per annum in the UK. Suitability, conditions and best forms of inclusion of cullet in concrete are now investigated extensively. As a complementary study, present work focuses on the dissolution characteristics of cullet when in contact with the pore fluid of hydrating cement. Cullets from white, amber and green bottle glasses were exposed to three types of simulated pore fluids all being initially saturated in lime: (i) mixing tank model, (ii) free access to lime, and (iii) free access to lime at a higher concentration (in 10% saccharose solution). Evolution of simulated pore fluid chemistries is reported and reaction products are characterised by XRD, thermogravimetry, particle size distribution and SEM techniques. Dissolution and long-term reactions of cullet are estimated by thermodynamic phase equilibrium calculations. By considering only the chemistry of its inclusion in concrete, waste glass cullet would generate C-S-H gel and thus contribute to strength development.

• INTRODUCTION

• OBJECTIVES

• EXPERIMENTAL WORK

• MEASUREMENTS PERFORMED

• RESULTS AND OBSERVATIONS

• OVERALL CONCLUSIONS

• REFERENCES