Characteristics of produced concrete become changedthrough changingthe characteristics of materials constituting the concrete. These changes include: The quality of cement, the real ration of water to cement: with neglecting the further water within the aggregates or lack of that, the consideredratio fluctuates and the characteristics of the aggregate which are related to the following dimensio...

Nowadays, concrete with strength higher than 50 MPa is utilized due to the ever increasing need for higher strength and prolonged healing properties. Despite the widespread use of high-strength concrete, only a few research projects have been conducted on the punching shear strength of high-strength concrete slabs. Reinforced concrete flat slabs are widely employed in structural systems. The lo...

Nanotechnology will serve as a suitable solution to achieve high performance in future construction and construction. Using this new technology, creativity and innovation can be achieved in the building industry. one of these new technologies of smart concrete is that in recent years, many researches and experiments have been done in scientific research centers around the world, so that the con...

this paper is based on an experimental research that examined the effects of concrete`s major parameters on durability of concrete pavements and curbs under freezing and thawing cycles. these parameters include concrete mix design parameters such as water-cement ratio, fine aggregate percentage and using air entraining admixture and simulating real freeze-thaw cycles that infrastructures underg...

    Freezing and thawing resulting from the ingression of water into concrete causes cracking or spalling. Corrosive ions such as chloride or sulfate penetrate the concrete surface and eventually reach the reinforcing steel. This causes the steel to corrode.     Because of the high maintenance and replacement costs, responsible officials should be increasingly concerned about the growing number...

Astronomical observations demand the existence of dark matter, however no suitable candidates have been observed at the Large Hadron Collider or elsewhere so far. This poses a challenge both for model building and for the theoretical tools with which a given model is addressed. After a gentle introduction, issues related to the latter challenge are reviewed. Finally, as a concrete example, we i...

The recently obtained results on e+ehadrons and multigamma production in pp collisions provide some support for a previously made argument that heavy, highly charged subnucleons may exist, and a search for such particles in the cosmic rays has been made. In 620 hours no candidates were detected, and an upper limit for the unaccompanied particle flux of 7 . 10 -10 cm-2sec-lsr-l at sea level unde...

The shielding for 14-MeV neutrons from a D-T generator at SLAC needs to be optimized in terms of shield thickness and cost. Shielding calculations were made using the MCNP4B Monte Carlo code and the ENDF/B-VI cross section set. A few materials were studied: iron, borated polyethylene, three types of normal and heavy concrete, and mixtures of iron and borated polyethylene. The effects of shieldi...

A high-resolution finite element model is developed using the MSC.Marc software package to investigate local bond behavior and the modeling of this behavior. In the model, interaction between concrete and steel is treated geometrically as contact between two separate bodies. Concrete is modeled as a homogenous material. A multiple, fixed, smeared crack model is used to simulate response in tens...