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...

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...

Background: Biological shielding of nuclear reactors has always been a great concern and decreasing the complexity and expense of these installations is of great interest. In this study, we used datolite and galena (DaGa) minerals for production of a high performance heavy concrete. Materials and Methods: Datolite and galena minerals which can be found in many parts of Iran were used i...

concrete is one of the most important construction materials widely using in hydraulic structures, such as lining of irrigation canals. concrete durability might be decreased due to the environmental or inner factors with physical, chemical or mechanical reactions. since, the climatologically condition is variable in most part of the country, local studies are needed to evaluate of the weakness...

pervious concrete is a concrete mixture prepared from cement, aggregates, water, little or no fines, and in some cases admixtures. the hydrological property of pervious concrete is the primary reason for its reappearance in construction. much research has been conducted on plain concrete, but little attention has been paid to porous concrete, particularly to the analytical prediction modeling o...

concrete has a special place at the current century; it has been and is the most widely used building material. producing concrete has several environmental impacts that should be considered to prevent consequent problems. in recent years, several methods have been developed to produce concrete that is compatible with the environment and sustainable development basis. in these concretes, beside...

semiconducting carbon nanofibers (cnf) are prepared from three different sources, i.e., acetylene, ethanol, and cotton by the chemical vapor deposition (cvd) process. these fibers are having rich elastic, engineering and conductivity properties. fresh self-compacting concrete (scc) flows into place and around obstructions under its own weight to fill the formwork completely and self-compact, wi...

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...