Structural behavior of seawater sea-sand concrete shear wall reinforced with GFRP bars

A combination of coral reef sand (CRS) concrete and fibre-reinforced polymer (FRP) bars provides an effective solution to the durability deficiency in conventional RC structures. This study experimentally investigates the durability of CRS concrete beams reinforced with basalt FRP (BFRP) bars in a simulated marine environment. Flexural tests are conducted on a total of fourteen CRS concrete beams aged in a cyclic wet-dry saline solution at temperatures of 25, 40 and 55°C. The variables comprise the types of reinforcement (steel and BFRP), the aging duration and the temperature. The failure modes, capacities, deflections and crack development of the beams are analysed and discussed. The results indicate that the ultimate load of the beams exhibits no degradation after aging, whereas the failure mode of the BFRP-CRS concrete beams transition from flexure to shear, which is caused by the degradation in the mechanical properties of the stirrups. The aged BFRP-CRS concrete beams show a substantial increase of over 70% in their initial stiffness compared with the control beams (beams without aging) and a substantial decrease in their crack width after aging due to the prolonged maturation of the concrete. Furthermore, a formula for calculating the shear capacity in the existing code is modified by a partial factor equal to 2, which can predict the capacity of a CRS concrete beam reinforced with BFRP bars in a marine environment.

Section: Introductionmentioning

confidence: 99%

Durability of coral-reef-sand concrete beams reinforced with basalt fibre-reinforced polymer bars in seawater

Wang

Shi

Ding

et al. 2021

“…These investigations mainly analyze the coupled effects of RCA replacement percentage and sea sand Cl − content on the properties (workability, strength and deformation) of RACSS (Huang et al, 2018). Xiao et al (2018), Zhang et al (2019) and Kumar et al (2016) reported that the low clay content and desired size fractions of sea sand reduced the negative influence of RCA on the workability of concrete (Bravo et al, 2015; Poon et al, 2009). The workability of RACSS could meet the requirements of engineering.…”

Section: Introductionmentioning

confidence: 99%

Mechanical behaviors of GFRP tube confined recycled aggregate concrete with sea sand

Huang

2020

Self Cite

An experimental program was undertaken to study the mechanical behaviors of glass fiber-reinforced polymer (GFRP) tube confined recycled aggregate concrete with sea sand (GRACSS) under the axial compression. Two different parameters were mainly considered: recycled coarse aggregates (RCA) replacement percentage (0, 100%) and type of sand (sea sand, river sand). Typical influences of RCA and sea sand on the strength, the deformation and the load–deformation curve of GRACSS were investigated. The test results showed that the failure pattern of GRACSS was similar to that of GFRP tube confined ordinary concrete (GCOC). The strength of GRACSS decreased with an increasing RCA replacement percentage, while sea sand could reduce the negative effect of RCA. It is also found that the peak deformation of GRACSS increased with the increasing RCA replacement percentage whereas with decreasing sea sand chloride ion (Cl–) content. The stiffness of the specimen was obviously influenced by the concrete type. Research findings indicated that the axial load-deformation curve of GRACSS can be divided into elastic-plastic and hardening stages. An analytical expression was proposed to calculate the load-deformation curve of GRACSS. Finally, the finite element method (FEM) was applied to study the effects of outer tube thickness, concrete strength, RCA replacement percentage and Cl– content in sea sand on the mechanical behaviors (strength and deformation) of GRACSS.

“…FRP-SSC structures). With this idea, a large number of investigations on FRP-SSC structures have been executed, including the FRP-SSC beams (Dong et al, 2018(Dong et al, , 2019(Dong et al, , 2020Jiang et al, 2019), FRP-SSC columns (Li et al, 2016a(Li et al, , 2016b(Li et al, , 2018a(Li et al, , 2018b(Li et al, , 2018cZeng et al, 2020;Zhang et al, 2019b), and FRP-SSC shear walls (Zhang et al, 2019a).…”

Section: Introductionmentioning

confidence: 99%

Experimental study on stress-strain curves of seawater sea-sand concrete under uniaxial compression with different strain rates

Zhang

2020

Self Cite

In order to investigate the mechanical properties of seawater sea-sand concrete (SSC) under uniaxial compression, the SSC prisms with different mix proportions are designed and prepared, and the compressive strength and stress-strain curves under uniaxial compression are tested, in which five loading strain rates 10−5/s, 10−4/s, 10−3/s, 10−2/s, and 10−1/s are selected. The failure patterns of the SSC specimens under different strain rates are discussed, and the peak stress, peak strain (strain at the peak stress), elastic modulus, and ultimate strain are analyzed. The influence of the strain rate and the shell particle content on the stress-strain curves is intensively evaluated. It shows that the peak stress and elastic modulus increase with an increasing strain rate while the peak strain and ultimate strain have no obvious trend. Additionally, the shell particles seem to have contributions to the increase of the compressive strength of SSC base on the test results of cube and prism specimens, but further considerations about this phenomenon are necessary. Finally, the dynamic increase factor (DIF) of characteristic indices of SSC is put forward.