Failure modes in recent earthquakes on lightly reinforced shear walls includes rebar fracture and out of plane buckling of its boundary elements. In latest edition of ACI 318 and also latest amendment of NZS 3101-2006 to avoid rebar fracture in boundary elements, the minimum reinforcement ratio for shear walls is increased. This experimental study investigates that rather than increasing reinfo...

Reinforced concrete is a composite material consisting in a rebar embedded in a concrete matrix. The structural equilibrium depends of the quality of bond between the two materials as well as the intrinsic quality of each of the components. When the structure is submitted to heating, cracking can occur due to the difference in thermal expansion properties between the two materials. In the prese...

The precast concrete structure has the advantage of a short construction period, less labor consumption, and pollution. lapped-rebar splice is type connection for assembled reinforced shear walls in structure. In this study, anchoring performance short-lapped-rebar with corrugated metal duct spiral hoops investigated. A total 30 specimens were designed considering influences rebar diameter lapp...

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...

Considering economical reasons and attempting to reduce carbon foot print of concrete structures, there is increasing tendency toward use of high strength reinforcement in seismically active regions. ACI 318-19, Iranian steel rebars standard INSO 3132 and next edition of Iranian national building allow the use of high strength rebars in elements of ductile force resisting systems. Therefore it ...

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...

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...