Shear capacity of reactive powder concrete beams using high-strength steel reinforcement

Abstract In order to study the shear behavior of high-strength reinforced Reactive Powder Concrete (RPC) beams, eight test beams were designed and fabricated for the shear test under symmetrical concentrated load. By observing the development and failure mode of diagonal cracks, the influence of shear span ratio, stirrup ratio, and longitudinal reinforcement ratio on the cracking load, shear capacity, and deflection of the test beam is analyzed. The results show that: in a specific range, the shear capacity increases with the increase of stirrup ratio and longitudinal reinforcement ratio and decreases with the increase of shear span ratio. The shear span ratio has the most significant influence on the component’s failure mode and deformation capacity. The increase of the stirrup ratio can improve the deformation capacity of the component in a specific range. It is conservative to use the code to design concrete structures to calculate the shear capacity of high-strength reinforced reactive powder concrete beams. It is suggested that the shear calculation formula suitable for high-strength reinforced reactive powder concrete should be adopted to make the theoretical calculation results closer to the measured values.

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Static Properties of Plain Reactive Powder Concrete Beams

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.302-303.521 ◽

2006 ◽

Vol 302-303 ◽

pp. 521-527 ◽

Cited By ~ 4

Author(s):

Ri Gao ◽

Zhi Min Liu ◽

Li Qian Zhang ◽

Piet Stroeven

Keyword(s):

Mechanical Properties ◽

Crack Extension ◽

Steel Fiber ◽

Concrete Beams ◽

High Strength ◽

Reactive Powder Concrete ◽

Static Properties ◽

Simply Supported ◽

Reactive Powder ◽

Strength And Durability

Reactive powder concrete (RPC) is a new kind of ultra-high strength and upper ductility concrete first developed in 1990’s in France. In this paper, the RPC mixture proportion is optimized and its mechanical properties, such as compressive strength, flexural strength, elastic modulus, and its durability, are tested and discussed. Based on the optimal mixture proportion, four simply supported plain RPC beams (without reinforcement bars) are made and tested. The mechanical properties of plain RPC beams, including section deformation, load-displacement relationship, failure forms, crack distribution, crack extension, and ultimate flexural capacity, are discussed. It is concluded that RPC is an excellent material with high strength and durability. Steel fiber is important both to control the crack extension and to enhance the ductility of RPC beams.

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Shear performance of single-keyed dry joints between reactive power concrete and high strength concrete in push-off tests

Science Progress ◽

10.1177/0036850420928643 ◽

2020 ◽

Vol 103 (2) ◽

pp. 003685042092864

Author(s):

Jiahui Feng ◽

Weibin Liang ◽

Haibo Jiang ◽

Chengwang Huang ◽

Jingyuan Zhang

Keyword(s):

Compressive Strength ◽

High Strength ◽

Shear Capacity ◽

Steel Fibers ◽

Reactive Powder Concrete ◽

Concrete Compressive Strength ◽

Strength Concrete ◽

Shear Key ◽

Shear Performance ◽

Reactive Powder

Shear key joints are commonly used in constructions of precast concrete segmental bridges. Most researches focused on shear performance of the dry joints with the identical-strength concrete, leaving a research gap on that of composite joints between different concrete segments. This research aims to investigate shear behavior of shear key joint between reactive powder concrete and high strength concrete. Totally 12 specimens of single-keyed dry joint were tested, with the parameters of concrete compressive strength, steel fibers, and confining stress. The experimental results indicated that shear failure was observed, but crushing phenomenon occasionally occurred in composite joints in testing, which was confirmed by stress distribution from numerical simulation. In terms of shear capacity of composite joint, peak shear loads of reactive powder concrete specimens without steel fibers were enhanced by 10%–12% as increasing of concrete compressive strength, while those with steel fibers achieved 22%–25% enhancement. Nevertheless, a slight reduction of normalized shear strength was obtained because of its lower volume fraction of coarse aggregate. In numerical simulation, as increasing the concrete compressive strength of convex part, peak shear load was enhanced, but the increment rate of peak shear load decreased. Shear design formulae underestimated shear capacity of reactive powder concrete specimens with steel fibers, but the models proposed by Buyukozturk and Rombach gave accurate predictions on those without steel fibers.

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