DESIGN AND DEVELOPMENT OF RESIN CAPSULE ANCHORING SYSTEMS FOR STRENGTHENING THE CONCRETE SURFACE USING DESIGN-EXPERT SOFTWARE

The demand for strengthening of concrete structures has resulted in an increased use of chemical bonded anchors. Therefore, investigating the formulation and mechanical properties of adhesive grout layer has become an important issue. Different formulations of polyester resin grout were designed by Design-Expert software and their uniaxial compressive strength, volume shrinkage, gel time and maximum exotherm temperature were obtained. In addition, their rheological behaviors once the reinforcing bar is inserted were evaluated. Having optimized the above parameters by means of mixture D-optimal method, the most efficient formulation of chemical bonded anchors was developed. The effect of adding thixotropic additives and different rotational speed of anchors on the rheological behavior of optimum mixture were investigated and the resin capsule was produced. The most significant factors increasing compressive strength and volume shrinkage are resin and monomer content. Inhibitor concentration decreases both responses dramatically. Silica fume not only improves the rheological behavior of the grout, but also increases its storage time.

Keywords:

chemical bonded anchors , polyester resin grout , mixture d-optimal , thixotropic behavior