micro silica (ms) is an extremely fine, spherical powder that is used as an additive for improving concrete performance. it is obtained as a by product of silicon metal and ferrosilicon alloy production.  due to its pozzolanic nature, micro silica can be used to enhance the qualities of both  fresh  and  hardened  concrete. addition of micro silica into the concrete as a cement replacement, dec...

Compressive strength and concrete slump are the most important required parameters for design, depending on many factors such as concrete mix design, concrete material, experimental cases, tester skills, experimental errors etc. Since many of these factors are unknown, and no specific and relatively accurate formulation can be found for strength and slump, therefore, the concrete properties ca...

With many years of construction and application of common concrete, researchers have always been searching for a better composition. One of the notable ideas for achieving such a composition is using recycled materials. One of the materials which is suitable for environment and constant development is damaged tires .For studying mechanical properties of concrete containing tire particles, a ser...

one important application of fiber reinforced polymer (frp) is to confine concrete as frp jackets in seismic retrofit process of reinforced concrete structures. confinement can improve concrete properties such as compressive strength and ultimate axial strain. for the safe and economic design of frp jackets, the stress-strain behavior of frp-confined concrete under monotonic and cyclic compress...

In this research, the effect of the cement, sand, and pumice mixture on the durability of lightweight concrete is investigated. The intention of this paper is to replace a certain amount of the pumice percentage as an alternative option of the cement and pumice sand aggregate with conventional sand components. The experimental results include compressive strength, ion-chloride emission factor (...

In this research, the performance of ultrasonic pulse velocity (UPV) in concrete is examined as a nondestructive experiment in order to estimate mechanical (compressive and tensile strength) and durability (water absorption) properties of fiber-reinforced self-compacted concrete For this purpose 11 mixture designs containing 3 types of fibers (steel: 0.1, 0.2, 0.3 and 0.4 percent by volume, Pol...

as regards if curing stops for some time and then resumes again, then strength gain will also stop and reactive, in this study with choose suitable curing conditions after improper first curing (recurring) for normal and silica-fume concrete, effect of this curing conditions on strength and permeability was investigated. the results from tests such as compressive strength, capillary water absor...

Given the development of construction industry and design and implementation of high rise buildings with complex sections and various geometrical forms, the use of self-compacting concretes has received the attention of construction engineers and provided great advantages. Due to the increasing air pollution in cities, governments encounter the important issue of repelling the pollutants in whi...

the present work has been performed to eliminate sewage dry sludge of alborze city wastewater treatment plant by using them as fine aggregate in concrete. on this basis, at first the selected dry sludge was analyzed for xrd and xrf for crystalline phases and chemical composition, respectively. the results showed that more than 50% of the sludge is formed of sio2 and it had more than 20% organic...