Durability of steel reinforced concrete in chloride environments: An overview

Tribology of electroless nickel coatings – A review

A design scheme for self-reinforced cementitious composites to be used for building-scale 3D printing processes is introduced. The design is based on that of engineered cementitious composites, which include dispersed short polymer fibers to generate robust tensile strain-hardening. The mechanical property profile of these printable ECC materials is meant to eliminate the need for steel reinforcement in printed structures, providing more freedom and efficiency for building-scale 3D printing processes. The fresh state rheological properties have been systematically manipulated to allow printability. Effects on fresh state workability of several compositional ingredients and processing parameters are investigated herein. To maintain consistent printing performance with a batch mixing approach, thixotropy in the fresh state is exploited to temporarily decouple hardening behavior from the processing timeline. Minimal workability loss under continued shear agitation is achieved. Mechanical properties of the printable materials are characterized and the printability of the materials is demonstrated.

A self-reinforced cementitious composite for building-scale 3D printing

On the rheology of using geopolymer for grouting: A comparative study with cement-based grout included fly ash and cold bonded fly ash

A scientometric review of geopolymer concrete

Electroless deposition process has undergone numerous changes to meet the challenging needs for a variety of industrial applications ever since the invention of the process during 1947. Among the various metals that can be electrolessly plated, electroless nickel has proved its supremacy for producing coatings with high corrosion resistance, hardness, wear resistance and uniformity. Electroless nickel can be deposited from a variety of baths and the coating properties depends upon the type of reducing agents and other deposition conditions. Electroless nickel–boron coatings have received considerable interest nowadays because of the superior hardness, corrosion and wear resistance characteristics. In this paper, the authors have reported on the development of a biodegradable electroless Ni–B bath and evaluated its characteristic properties. The influence of bath constituents, temperature and pH on the rate of deposition was studied. Scanning electron microscopy, X-ray diffraction, X-ray fluoresce...

Studies on development of electroless Ni-B bath for corrosion resistance and wear resistance applications

Many researches have been carried out in the area of fly ash utilization in the past. It mainly concentrated on replacement of cement with fly ash but production of artificial aggregates with fly ash helps in utilizing large volume of ash in concrete. The world is much interested in this part recently due to this large-scale utilization which also reduces environmental pollution and dwindling of natural resources. This paper mainly focuses on manufacturing process of light weight aggregates using pelletizer and curing has been done in cold bonded technique. The properties of these fly ash aggregates have been tested and compared with natural gravel and the study shows that cold bonded fly ash aggregates can be used as an aggregate replacement material in concrete. The strength property and density of concrete made with artificial fly ash aggregates and natural gravel were also studied which confirms that introduction of fly ash aggregates in concrete reduces the compressive strength but meets the required strength to be used as a structural material.

Experimental study on Cold Bonded Fly Ash Aggregates

This paper presents an experimental investigation on the Impact failure energy and strength reliability of fiber reinforced concrete (FRC) by using a simple drop weight test which was based on the testing procedure recommended by ACI committee 544. Two different steel fibers were used as the reinforcing material in various volume fractions such as 0%, 0.5%, 1.0% and 1.5% with a water cement ratio of 0.42. Furthermore, the two-parameter weibull distribution was used to analyze the experimental data in order to sort out a variation of test results. Using the weibull distribution, the impact failure strength reliability, in other words, the probability distribution according to which the concrete will fail, was obtained. The results indicated that the concrete containing a 1.5% volume fraction of fiber gave the best performance followed by 1.0% and 0.5% under impact loading. It was proven that the probabilistic distributions of the impact failure energy of seven types of samples approximately follow two-parameter Weibull distribution.

Impact resistance and strength reliability of fiber-reinforced concrete in bending under drop weight impact load

Study of mechanical and microstructural properties of geopolymer concrete with GGBS and Metakaolin

It is well known that concrete is characterized by its high compressive strength, yet its brittle mode of failure is considered as a drawback of high strength concrete when it is subjected to impact and dynamic loads. This study aims to investigate the impact resistance of fibre reinforced concrete (FRC), incorporated with steel fibres at various dosages. For this, a drop weight test was performed on the 28 days cured plain and fibre reinforced concrete samples as per the testing procedure recommended by ACI committee 544. Crimped and hooked end steel fibre of length 50 mm and an aspect ratio equal to 50 was added to concrete in different proportions i.e. 0%, 0.5%, 1.0% and 1.5% with water cement ratio of 0.42. From the test results, it was proved that the (FRC) was effective under the impact loads thus improving the impact resistance. Also, the reduction of strength under impact load in each specimen for every three blows was determined by ultrasonic pulse velocity (UPV) test. Further, a statistical correlation between (UPV) and number of blows under impact load was developed using regression analysis. The developed regression model predicts the reduction in strength of concrete under impact load accurately.

A. S. Santhi

Papers

Studies on development of electroless Ni-B bath for corrosion resistance and wear resistance applications

Experimental study on Cold Bonded Fly Ash Aggregates

Impact resistance and strength reliability of fiber-reinforced concrete in bending under drop weight impact load

Study of mechanical and microstructural properties of geopolymer concrete with GGBS and Metakaolin

Effect of Crimped and Hooked End Steel Fibers on the Impact Resistance of Concrete