Hybrid fiber reinforced concrete (HFRC) consisting of two or more different types of fibers has been widely investigated because of its superior mechanical properties. In the present study, the effect of the addition of steel (0.25%, 0.5%, 0.75%, and 1% of concrete volume) and Polypropylene (0.2%, 0.4%, and 0.6% of concrete volume) fibers on the surface scaling resistance of concrete, depth of ...

This research is conducted with a view to investigate performance of concrete containing high volumes of ASTM Class C fly ash. A portland cement concrete, proportioned to have 28-day compressive strength of 6,000 psi (41 N4Pa) is used in this study. Concrete mixes are also proportioned to have various levels of cement replacement by fly ash ranging from 40% to 70% by weight. Concrete performanc...

Ground granulated blast furnace slag is widely used as a mineral admixture to replace partial Portland cement in the concrete industry. As the amount of slag increases, the late-age compressive strength of concrete mixtures increases. However, after an optimum point, any further increase in slag does not improve the late-age compressive strength. This optimum replacement ratio of slag is a cruc...

To improve the performance of concrete, polymers are mixed with concrete. It has been observed that polymer-modified concrete (PMC) is more durable than conventional concrete due to superior strength and high durability. In this research, effect of Styrene-Butadiene Rubber (SBR) latex on compressive strength and flexural strength of concrete has been studied and also the optimum polymer (SBR-La...

In this research, 210 concrete cube specimens (15cm) were made replacing 0, 5, 10, 15, 20, 25, 30, 35, 40, 50, and 60 percent of slag powder from Isfahan Steel Mill for cement. The control specimens were made with 350 kg/m3 cement content and the water cement ratio in all specimens was 0.51. The Slump value and compressive strength of concrete specimens in 7, 28 and 90 days were obtained and th...

self-compacting concrete (scc) is a highly fluid yet stable concrete that can flow consistently under its own weight, pass between bars, and fill in formwork without the need of compaction. the application of scc effectively resolves the difficulties of concreting in situations with complicated formwork and congested reinforcements. in this paper, the bond between scc and steel reinforcement wa...

in order to investigate the flexural behaviors of rc beams after freeze-thaw cycles, compressive strength test of concrete cubes after 0, 50, 100, 125 freeze-thaw cycles were made, and static flexural experiment of 48 rc beams after 0, 50, 100, 125 freeze-thaw cycles were made. the relationships of relative compressive strength, mass loss rate, relative dynamic elastic modulus and numbers of fr...

This paper presents a new model for predicting the compressive strength of steel-confined concrete on circular concrete filled steel tube (CCFST) stub columns under axial loading condition based on Artificial Neural Networks (ANNs) by using a large wide of experimental investigations. The input parameters were selected based on past studies such as outer diameter of column, compressive strength...

In this study, first by surveythe parameters affecting the compressive strength, such as water to cement ratio, cementgrade, silica fume to cement percentage, and the various ratios oflight weight aggregate LECA, to total aggregate, Taguchi method is used, to test 9 mix designsobtained the mix design optimization. Since lightweight concrete is brittle like normal concrete, to resolve this probl...

fiber reinforced concrete (frc) has been widely used due to its advantages over plain concrete such as high energy absorption, post cracking behaviour, flexural and impact strength and arresting shrinkage cracks. but there is a weak zone between fibers and paste in fiber reinforced concretes and this weak zone is full of porosity, especially in hybrid fiber reinforced concretes. so it is necess...