By increasing the demolition of old concrete structures and the interest of civil industries to consume cheaper materials, using Recycled Concrete Aggregate (RCA) can cause environmental protection and decrease the construction costs. On the other hand, the high potential of Recycled Aggregate Concrete (RAC) in concrete industry was established by extensive experimental researches were performe...

todays applying concrete structures is more usual than other structures which are used in buildings as in most of the world’s countries the application ratio of concrete to steel has increased from 10 to 1. sometimes these structures require strengthening vulnerable members because of deficiency in their loading system in usual and critical conditions. there are different methods for strengthen...

The sections composed of concrete and steel, which include concrete-encased concrete-filled tubes, generally have defects due to the low tensile strength of concrete. Therefore, an appropriate method was used for the combination of concrete-filled tubes (CFT) and prestressing strands which is encased in concrete. The conventional design guidelines are commonly developed for materials with norma...

As a vibration- free concrete, self- compacting concrete (SCC) can be easily used in the absence of consolidation, therefore; it is a good option for repairing and retrofitting concrete structures. The quality of repair layer is highly effective on a successful repair. Accordingly, in this study, factors affecting the quality of fiber-reinforced self-compacting concrete repair layer, including ...

seismic behavior of a rockfill dam with asphalt-concrete core has been studied utilizing numerical models with material parameters determined by laboratory tests. the case study selected for these analyses, is the meyjaran asphalt core dam, recently constructed in northern iran, with 60 m height and 180 m crest length. the numerical analyses have been performed using a nonlinear three dimension...

This study investigates the reinforcement correction factor of concrete core in more detail to prepare appropriate outlines for interpretation of results. This investigation aims to minimize uncertainties involved to carry out the more realistic condition assessment of suspect buildings before taking up retrofitting/strengthening measures. For this purpose, an extensive experimental program inc...

a parametrik investigation was conducted to study the non-linear behavior of precast and cast-in-place reinforced concrete beam-column connections subjected to tabas seismic forces (1979). the behavior of these types of connections in a four stories structure with respect to strength, ductility , stiffness, and bond deterioration at the joint core are presented and discussed. calculation result...

Steel-concrete-steel (SCS) sandwich panels are composed of two steel plates with low thicknesses and high densities and strengths and one thick layer between both plates with low strength and density known as core that is composed of concrete. Cohesive material-epoxy resin or shear connectors are usually used to connect the plates to the concrete core. SCS sandwich composites are being develope...

The main objective of this study is to evaluate the workability of fresh portland cement concrete while it is still in the mixing truck by determining fundamental rheological parameters (plastic viscosity and yield stress). Nine concrete mixtures with different values of yield stress and plastic viscosity were tested in a concrete truck. The measurements made with the truck were based on the ty...