Rebar fracture in boundary elements of lightly reinforced shear walls in recent earthquake motivated research on the minimum longitudinal reinforcement applicable to shear walls. These researches lead to change in the ACI 318-19 requirement for minimum longitudinal reinforcement in boundary elements. New ACI 318 requirement increase minimum longitudinal reinforcement ratio for boundary elements...

A before-and-after experimental design was conducted to evaluate the potential reduction in the risk of musculoskeletal injuries to concrete reinforcement workers when using an automatic rebar tying machine. Eleven (11) concrete reinforcement workers participated in this experiment. All dependent variables (trunk posture, and rebar tying time) were measured before and after implementing the reb...

The background and current state of the art of ground penetrating radar testing of rebar in concrete is briefly reviewed. This encompasses developments of Polarization in rebar detection, diameter detection, corrosion detection,neural network and other automatic method in rebar detection.

Initiation of corrosion on reinforcing bars occurs when a critical chloride concentration is achieved. A universal value for the chloride concentration that causes depassivation has not been agreed upon for carbon steels due to a variety of experimental factors. The chloride threshold depends on the rebar material, rebar surface condition, testing environment, method of detection, definition of...

As a preliminary study for the erection of floating structures using high performance concrete, this paper examines the bond characteristics between concrete and the reinforcing bar. Since the floating structure is constructed in aquatic environment, corrosion of the reinforcing steel is likely to develop more prematurely than in onshore structure in case of concrete cracking. A solution to thi...

Abstract Rock bolts are one of the main measures used to reinforce unstable blocks in a rock mass. The embedment length fully grouted stable and competent stratum behind is an important parameter determining overall bolt length. It required that section must be longer than critical ensure will not slip when loaded. Several series pull tests were carried out on rebar evaluate pull-out mechanics ...

Automated rebar detection in images from groundpenetrating radar (GPR) is a challenging problem and difficult to perform in real-time as a result of relatively low contrast images and the size of the images. This paper presents a rebar localization algorithm, which can accurately locate the pixel locations of rebar within a GPR scan image. The proposed algorithm uses image classification and st...

The life of a concrete bridge exposed to deicing salt or seawater has often been limited by corrosion of the steel reinforcement. The service life of a concrete structure, degraded by corrosion, is considered to be the sum of the initiation and propagation periods. The initiation phase is the time required for sufficient accumulation of aggressive species at the rebar surface to initiate corros...

The synthesis of rebar graphene on Cu substrates is described using functionalized boron nitride nanotubes (BNNTs) that were annealed or subjected to chemical vapor deposition (CVD) growth of graphene. Characterization shows that the BNNTs partially unzip and form a reinforcing bar (rebar) network within the graphene layer that enhances the mechanical strength through covalent bonds. The rebar ...

The effect of interfacial bonding of glass hollow microspheres and a polymer matrix on the elastic properties of syntactic foam was investigated using representative volume element (RVE) models, including partially debonded interfaces. Finite element analysis, with models having different debonding geometries, was performed to numerically estimate the elastic behavior of the models. The models ...