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...

Tasks: 1. To measure the impulse counting rate as a function of the distance between the source and the counter tube. 2. To determine the half-value thickness d1/2 and the absorption coefficient of a number of materials by measuring the impulse countAttenuation coefficient of different materials as a function of the material density (from left to right: Plexiglas®, concrete, aluminium, iron, le...

This paper investigates the mechanical and micro-interfacial properties of recycled concrete. Concrete specimens with brick coarse aggregate (RBCA) admixtures 0%, 25%, 50%, 75%, 100% were prepared. Apparent density, slump, tests carried out to evaluate behavior The evolution laws parameters such as compressive strength, peak strain, elastic modulus concrete tested analyzed. Combined numerical a...

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...

There is a worldwide interest in using fibers of different types in concrete mixtures. In this regard, as the use of PET fibers has gradually increased during the last decade, this study aims to investigate the effects of PET fibers on the mechanical properties of hardened concrete and the workability of fresh concrete. To this end, different contents of PET fibers (PC= %0, %0.5, %1 and %1.5) a...

Extremes of information combining inequalities play an important role in the analysis of sparse-graph codes under message-passing decoding. We introduce new tools for the derivation of such inequalities, and show by means of a concrete examples how they can be applied to solve some optimization problems in the analysis of low-density parity-check codes.

In the present study, a new method for retrofitting reinforced concrete beam is introduced in which steel-concrete composite jackets containing steel fiber is used. For this purpose, 75% of the peripheral surface of reinforced concrete beams was initially reinforced using steel plates and bolts, and steel fiber reinforced concrete was used between the steel plates and the peripheral surfaces of...

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...