Experimental Study on Crack Width of HRB600 Grade High-Strength Steel Bar Reinforced Concrete Beams

Abstract

High-strength reinforcement is an important direction in the development of civil engineering. In order to fill the gap that the current concrete structure code GB50010 has no standard regulations applicable to HRB600-grade high-strength reinforcement, this paper conducted an experimental investigation on the crack width of eight concrete beams reinforced with HRB600-grade high-strength reinforcement. The study examined various parameters to understand the crack development process, crack spacing, and factors influencing crack width in the pure bending section. The results revealed that the damage mode and crack development process of high-strength reinforced concrete beams were similar to those observed in ordinary reinforced concrete bending members. The crack spacing in the pure bending section was independent of the concrete strength, and the average crack width in the pure bending section exhibited a proportional relationship with the reinforcement strain. Moreover, both were mathematically related to the ratio of reinforcement diameter and ratio. A calculation formula for the maximum crack width suitable for HRB600-grade reinforced concrete beams was developed and fit. The HRB600-grade high-strength reinforcement had an obvious yield stage and good ductility, and the test study provides a powerful reference for promoting the application of high-strength reinforcement in concrete structures.

Experimental Study on Seismic Performance of Prefabricated Columns Connected Using a Novel Dry Sleeve

“…Liu [1] expounds the view that prefabricated buildings can effectively help realize the industrialization of construction projects and thus reduce the energy consumption of construction sites. In the past 10 years, the research on prefabricated concrete structures has been intensified, and much of the experimentation, modeling, and theoretical research has been done on precast concrete structure components (precast composite column) [2][3][4], material properties [5][6][7], structural vibration behaviors [8,9], node connections [10][11][12], construction method [13,14], or other points of prefabricated modular buildings. Ou [2] compared the seismic performance difference between an ultra-high-performance concrete (UHPC) prefabricated pipe concrete composite column and a conventional reinforced concrete column (RC column), and found that the stiffness, yield load, and ductility performance of the UHPC prefabricated composite column were better than those of the RC column in quasi-static tests.…”