Structural Behavior of Concrete Incorporating Glass Powder Used in Reinforced Concrete Columns

摘要

Binary and ternary binders are recommended for the production of concrete mixes used in infrastructure because these concretes are environmentally friendly. Moreover, concrete produced by using glass powder (GP) as a binder shows very low permeability to chloride ions. An extensive research project on the use of GP as cementitious material is underway at the University of Sherbrooke, Quebec, Canada. The northeastern Canadian province of Quebec has a policy on waste management to promote the recovery and management of materials from the municipal, industrial, commercial, and institutional sectors. Therefore, new alternatives for using recycled glass are needed. GP contains approximately 70% silicon dioxide. Thus, the replacement of 20% of cement with the incorporation of GP into the formulation of concrete provides economic and environmental benefits. Moreover, it has been shown that concrete with 20% GP has a very low permeability to chloride ions, which makes it a suitable solution for RC elements subject to corroding conditions, such as deicing products or a salty atmosphere. This paper presents results from a study on the structural behaviour of RC columns incorporating GP. Three series of six columns were tested under axial compression to show that RC columns made with GP show satisfactory structural behavior. The specimens had varying amounts of transverse reinforcement. For each series, three columns containing 20% GP as a cement replacement and three columns containing regular cement were tested. The results showed that for a water-binder ratio (w/b) of 0.40, the replacement of 20% of cement by GP delayed cracking of the concrete cover and slightly improved the load-carrying capacity and the postpeak response for columns tested at 28 days. For w/b = 0.55, the results (i.e., load at first crack, peak load, and first observation of concrete spalling) for columns with GP tested at 91 days were still slightly lower than those without GP. However, the difference was smaller than for columns with the same w/b that were tested at 28 days. Overall, the results showed that the structural behavior of RC columns made using concrete with GP is similar to columns made with normal concrete. According to these results, it is possible to use concrete with 20% GP for the construction of sustainable building structures.