Recent tendencies in concrete technology have been towards to high- performance concrete with a low water-cement ratio. However, high performance concretes have some problems. One of the problems is early-age cracking due to autogenous shrinkage. This study presents the results of an experimental investigation carried out to evaluate the autogenous shrinkage of high-strength concrete. Accordi...

In this paper, the properties of concrete containing zeolite and tuff as partial replacements of cement and sand were studied. The compressive strength, water absorption, chloride ion diffusion and resistance to acid environments of concretes made with zeolite at proportions of 10% and 15% of binder and tuff at ratios of 5%, 10% and 15% of fine aggregate were investigated. The results showed th...

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 rep...

In this research work, the effect of rice husk ash (RHA) along with and without superplasticizer (SP) on properties concrete was investigated. The good workability compaction is key parameter for strength durability concrete, it may achieved by adding SP in to concrete. India RHA available huge quantity. It byproduct agriculture. present ordinary portland cement (OPC) replaced 10 50% RHA. fresh...

In recent decades, concrete technology has reached the broad-based areas of operations through implementation Self Compacting Concrete to increase performance. Due high silica content, pozzolonic characteristic RHA makes it as a supplementary material for cement. this paper, Cement was partially replaced with Rice Hush Ash 5%, 10% 15%, 20%, 30% and 40% influencing properties SCC. The aim report...

This paper deals with the issues of air entraining and water/cement ratio in Portland Cement Concrete as related to its freeze thaw durability. Practices have been in place for nearly thirty years which demanded high early strengths in Portland Cement Concrete pavements. This paper looks at those practices, investigates the correlation between water/cement ratio and air entraining, and presents...

A unique, multi-phase, random, complex, and composite material, concrete provides both strength and impermeability to engineered structures. Unlike most construction materials, the properties of concrete continue to develop over time and in place—assisting processing and fabrication. Testing and quality assurance, however, become more complicated. For instance, having to wait 28 days to ensure ...

Nano materials have been widely used in laboratory and industrial scales in order to improve various properties of concrete and concrete mixture. The mainstream practice of the researches in this field is to add metallic nano-particles into the concrete mixture. The present research focuses on adding Micro-Nano Air Bubbles (MNAB) into water before mixing it with aggregate and cement mixtures. I...

Wisconsin Department of Transport (WisDOT) permits use of Grade A-FA (70% cement plus 30% Class C fly ash) concrete mixtures for pavement construction. This paper discusses a laboratory investigation performed to study the effects of the cementitious materials such as portland cement, ASTM Class C fly ash, ground granulated blast furnace slag (GGBFS), blends of cement and fly ash, and cement pl...

For more than 100 years, the primary theme underlying the NBS/NIST staff contribution to the crystallography of building materials has been the development of an improved understanding of concrete materials performance. Over that time period, portland cement concrete has become one of the most important of our construction materials for roads, buildings, and other large municipal structures. At...