Ultrahigh performance concrete (UHPC) is increasingly making its way into the construction field. Characterization of UHPC has therefore received much-needed attention in the research arena. One effective application of UHPC is in combination with high-strength steel (HSS) reinforcing rebar in shallow beams or slabs. However, bond and development characteristics of HSS rebar in UHPC have not yet been investigated. This paper presents the experimental results of the pullout and flexure tests conducted with HSS rebar in UHPC. This work was a part of a larger project to develop a new light-weight UHPC-HSS bridge deck system for a moveable bridge. Because the bridge deck was designed with #10 and #22 rebar as the main reinforcement, only these two rebar sizes were used in the experiments. First, pullout specimens were tested with three different embedment lengths of 8, 10, and 12 times the rebar diameter. Then, from the results of pullout specimens, beam specimens were tested with embedment lengths of...

Recycled aggregates have been widely studied and used in concrete products nowadays. There are still many waste materials that can be used as recycled aggregates other than crushed concrete particles. This paper aims to study the property variations of sustainable concrete paving block incorporating different contents of construction wastes. Five different types of waste materials were used in this project, including: recycled concrete coarse aggregate (RCCA), recycled concrete fine aggregate (RCFA), crushed glass (CG), crumb rubber (CB), and ground granulated blast furnace slag (GGBS). According to the test results of the properties of blocks mixed with different levels of wastes materials, it is concluded that adding both RCCA and RCFA in the block can decrease its strength and increase the water absorption. The suggested replacement levels for RCCA and RCFA are 60% and 20%, respectively. Mixing crushed glass in the concrete paving blocks as a type of coarse aggregates can improve the blocks’ strength and decrease the blocks’ water absorption. Addition of crumb rubber causes a significant deterioration of blocks’ properties except for its slip resistance.