background: high density concrete is extensively used for efficient radiation attenuation in radiotherapy rooms and nuclear reactors. over the past eight years, some efficient galena-based concrete samples for shielding x or gamma rays was produced. the goal of this study was to produce a novel high density concrete against neutron and photon radiations using tourmaline and galena. materials an...

in fact the most suitable method for finding the load bearing capacity of a member under the axial load or axial load and bending is make use of the interaction diagrams. to analysis and design the hollow circular, square and rectangular high strength concrete (hsc) column shapes, a linear strain variation was assumed in the cross-section height of the members and then the static equilibrium eq...

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...

Reinforced concrete structures consists of two main components and the behavior of these structures influenced by gender and material properties, in order to investigate the behavior of concrete reinforced beam that most important flexural element in reinforced concrete structures, we chosen High Strength Concrete (HSC) for concrete and GFRP and steel bars for reinforcement. For compare the new...

hot or cold weather condition affects the quality of the concrete in different ways, which one of them is increase or decrease in the initial temperature of the concrete. in this study, the impact of the initial temperature of the concrete on its quality in concrete kerbs made by dry pressing method with portland cement is examined. concretes with similar mix designs and initial temperatures of...

Background: In megavoltage radiotherapy rooms, ordinary concrete is usually used due to its low construction costs, although higher density concrete are sometimes used, as well. The use of high-density concrete decreases the required thickness of the concrete barrier hence, its disadvantage is its high cost. In a nuclear reactor, neutron radiation is the most difficult to shield. A method for p...

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...