This paper summarizes the research findings of the fundamental characteristics of high-strength concrete for the flexural design of bridge girders. The main objective of the research is to provide recommended provisions to the AASHTO-LRFD Bridge Design Specifications to extend the use of concrete strength up to 18 ksi. A total of 15 plain concrete specimens were tested under eccentric compressi...

The strength of concrete is a function of the proportions of the constituent materials, namely, cement, water, fine and coarse aggregates. The conventional methods used to determine the mix proportions that will yield the desired strength, are laborious, time consuming and expensive. In this paper, a mathematical method based on modified regression theory is formulated for the prediction of con...

The addition of steel fibers into concrete improves the postcracking tensile strength of hardened concrete and hence significantly enhances the shear strength of reinforced concrete reinforced concrete beams. However, developing an accurate model for predicting the shear strength of steel fiber reinforced concrete (SFRC) beams is a challenging task as there are several parameters such as the co...

this paper introduces an innovative partially destructive method, called “twist-off”, for the assessment of in situ concrete strength. in this method a 40mm diameter metal probe is bonded to a concrete surface by means of a high strength epoxy resin adhesive. to measure the concrete compressive strength, a torque is applied using an ordinary torque-meter and the maximum shear stress at failure ...

High-strength concrete (HSC) has been broadly applied to various civil structures for its advantages including high compressive strength and excellent durability creep resistance. However, the brittleness of HSC raises concern about use in practice. So far study on continuous reinforced beams is limited. This work investigates structural response beams, results are compared with those counterpa...

The construction methods currently adopted for multi-story concrete buildings resorts the strategy to cast columns and slabs with high normal compressive strength, respectively. intersection region affects load transfer performance of columns, causing expressive confinement stress in interior columns. However, when is only provided by two sides, as corner it not enough increase lateral stress. ...

The project aims to study tensile softening behavior of fiber reinforced concrete .Concrete is very much weak in tension but by addition of randomly oriented short crimped steel fibers will change the behavior from brittle to ductile. In the present work, the steel fibers were added at the volume fraction, being 0%, 0.5%, 1%, 1.5% to the normal strength concrete and high strength concrete. The ...