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...

This paper presents a study about Machine Learning approach for modeling the stiffness of different high-modulus asphalt concretes (HMAC) prepared in laboratory with harder paving grades or polymer-modified bitumen which were designed without reclaimed (RA) content. Notably, mixtures considered this are not part purposeful experimentation support modeling, but practical solutions developed actu...

this paper discusses about preparation of biodegradable polymer /clay nanocomposites based on organically modified montmorillonite clay; i.e. cloisite 10a and biodegradable polymer chitosan by solution mixing technique and their characterization. the nanocomposites were successfully prepared and their structures were characterized by powder x-ray diffraction (xrd), particle size analyzer (beckm...

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 limited number of studies are available on the impact polymer modified concrete corrosion effect Reinforced Concrete (RC) structures, such as bridges exposed to maritime environments or de-icing salts. The aim this research was analyse influence polymers mechanical and durability properties concrete. Seven types recyclable thermoplastic PCL, Polymorph, LDPE/EVA granular, powder, GPE, N-228 TP...

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...

For many concretes and mortars, self-desiccation results in the creation of empty capillary porosity within the cement paste microstructure, accompanied by a decrease in achieved hydration, an increase in internal stresses, and an increased propensity for early age cracking. One solution to this problem for low water-to-cement ratio concretes where external curing is ineffective has been the de...

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...

Introduction: The present study aimed to evaluate the impact of PbO nano and micro-sized fillers on ordinary and heavy concretes for different photon energies. Material and Methods: The MCNPX Monte Carlo code (version 2.6.0) was used for all simulations in the present study. A model of narrow-beam geometry was validated and utilized to calcul...