Abstract—In this study, the Compressive strength of concretes made with Ground Granulated Blast furnace Slag (GGBS), Pulverised Fuel Ash (PFA), Rice Husk Ash (RHA) and Waste Glass Powder (WGP) after they were exposed 780C (exposure duration of around 60 minutes) and then allowed to cool down gradually in the furnace for about 280 minutes at water binder ratio of 0.50 was investigated. GGBS, PFA...

Introduction: The heavyweight concretes have been widely used for constructing medical or industrial radiation facilities with photon sources. Materials and Methods: In this study, heavy concretes containing galena (PbS) and several borated minerals are proposed as suitable materials against photons. The shielding properties of 21 galena concretes containing seven borated minerals with three m...

Today concrete is most widely used construction material due to its good compressive strength and durability. Depending upon the nature of work the cement, fine aggregate, coarse aggregate and water are mixed in specific proportions to produce plain concrete. Plain concrete needs congenial atmosphere by providing moisture for a minimum period of 28 days for good hydration and to attain desired ...

Based upon the statistical distribution of flexural fatigue life data and flexural fatigue strength of the steel fibre reinforced concrete (SFRC) containing blends of limestone powder (LP) and silica fume (SF), the influence of these inserts on the flexural fatigue performance of concretes is probed. Concrete mixes were proportioned to replace 30% cement with these mineral inserts in different ...

The paper presents the results of tests on the effect of the low calcium fly ash (LCFA) addition, in the amounts of: 0% (LCFA-00), 20% (LCFA-20) and 30% (LCFA-30) by weight of cement, on fracture processes in structural concretes. In the course of the experiments, compressive strength of concrete and fracture toughness for: I (tensile), II (in-plane shear) and III (anti-plane shear) models of c...

This study comparably assessed the pozzolanic effect of silica fume (SF) and ground rice husk ash (RHA) as supplementary cementing materials on the properties of blended cement pastes and concretes. A commonly commercial silica fume (SF) and locally-produced rice husk ash (RHA) samples with two finenesses (one with larger size than cement and the other with smaller size than cement) were used i...

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...

Sulphates usually affect calcium aluminates in cements. Sulphate ions might have negative effects on cement hydration and it would be a reason of decrease in cement strength. In this study, the effects of Na2SO4 solution on the concretes made from OPC with oil shale ash (OSA) addition (0, 15 and 30%) were investigated. Concretes with 15% OSA gave the lowest value of Length Change Factor (LCF). ...

A coupled elastoplastic-damage constitutive model taking into account chemo-induced elastoplastic-damage effects for the modeling of coupled chemothermo-hygro-mechanical behavior of concretes at high temperature is proposed in this article. A three-step operator split algorithm for the integration of the rate coupled constitutive equations is developed. Consistent tangent modulus matrices for c...

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...