Mechanical Behavior of Concrete Reinforced with Waste Aluminium Strips

The main objective of this research work is to investigate the influence of the addition of waste materials, like aluminium waste material, Soft Drink Tin Fibers (SDTF) or soft tins to improve mechanical properties of concrete and also study the strength behavior of concrete, such as flexural strength and indirect or split tensile strength. It has been acknowledged that the use of fibers in concrete has considerable effects to improve strength parameters and characteristics of concrete. In this research work, similar efforts are made to present the effects of soft tin fibers or aluminium waste material as a reinforcing material in concrete and to assess the mechanical behavior of concrete. Particularly, this research work aimed to investigate experimentally the effect of soft drink tins on tensile (cylinder splitting tensile strength) and flexural strength. Soft tin fibers of 25.4  5  0.5 mm in size were used and added from 1 to 5% by the weight of cement with the design mix of 1:1.624:2.760 at 0.50 w/c ratio. Therefore, 6 batches (every batch contained 3 prisms and 3 cylinders) were prepared and cast for evaluation of tensile and flexural strength. One batch was cast without inclusion of fibers (controlled batch) and remaining 5 batches were cast with the addition of fibers using 1, 2, 3, 4, and 5% respectively. It was revealed from obtained results that split tensile strength and flexural strength of specimen increases as compared to controlled batch up to 4% addition of fibers. Moreover, beyond 4% soft drink tin fiber level, strength begins to fall down. Thus, it can be suggested that mechanical properties of concrete can be enhanced by 4% of soft drink tin fibers. Moreover, in this study, soft drink tin fibers (SDTF) or aluminium waste are used as the application of utilization of waste materials as a partial construction material and also on another side it controls the solid waste and environmental pollution. Doi: 10.28991/cej-2021-03091718 Full Text: PD

Mechanical properties of concrete by replacement of fine aggregate with desert sand

In this research study, the mechanical characteristics of concrete were investigated by substituting desert sand as fine aggregate. Desert sand obtained from Tharparkar was used in five different proportions (0%, 25%, 50%, 75%, and 100 %,). Several tests were carried out to understand the behaviour of concrete made with desert sand as a fine aggregate substitute including those for gradation, chemical composition, slump, density, water absorption, and compressive and tensile splitting tests. The grain size distribution analysis of desert sand revealed that it contains particles with a size of 0.45 mm, and the water absorption of desert sand concrete was found to be 1% higher, whereas workability fell by 6%. The compressive and tensile strength of a concrete mixture containing 75% desert sand was found to be 9.5% and 16.4% respectively higher than nominal concrete made with hill sand, and the average strength rise was on 3.5% and 2% respectively. Substitution beyond 75% was not given desirable results due to the fineness of desert sand. All the test results show that 75% substitution of desert sand as fine aggregate can be used in concrete production under designed concrete standards

Reducing the Effect of Carbonation and Corrosion in Rice Husk Ash Concrete by Incorporating Polymer

Durability plays a vital role in life of a reinforced concrete structural member. To increase service life of a structure, it is important to reduce corrosion potential and carbonation attack. In order to reduce the corrosion and carbonation effect in concrete structures, various supplementary cementing materials are used. In this study, a novel composite is introduced to reduce corrosion potential and carbonation attack on Rice Husk Ash Polymer Modified Concrete (RHAPMC). An experimental work was conducted to check the behaviour of corrosion and carbonation attack in control concrete, cement was replaced with RHAPMC concrete at the ages of 30 and 180 days. The results indicate that the effect of corrosion potential and carbonation has been significantly reduced with the addition of polymer in the cement replaced concrete

Characteristics of concrete modified with repackaged polymer-modified mortar and performance on repair and strengthening

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RELIABILITY OF LOCALLY MANUFACTURED STEEL BARS AS REINFORCEMENT FOR RC CONSTRUCTION

Theoretical approach based on stochastic methods is employed in order to perform statistical analysis on a very large spectrum of experimental data (the details of which is presented else where) with particular intention to propose the most appropriate values of structural properties of reinforcing steel bars manufactured locally in the country by making use of mainly various types of scrap as raw material. The study is conducted in terms of mean values, standard deviation, coefficient of variation and probability variant by selecting three different parameters i.e. diameter, manufacturer and location. Both lower and upper yield, 0.2 percent proof stress where ever applicable, ultimate stress and elongation have been considered separately for this analysis. Mild plain, deformed and high yield torsteel are the types of steel which have been included. This constitutes a total pool of 355 experimental values for each property. From the results it is observed that the coefficient of variation is quite high almost in every case

Investigating Optimum Conditions for Developing Pozzolanic Ashes from Organic Wastes as Cement Replacing Materials

This research was performed to investigate the optimum conditions for developing pozzolanic ashes from organic wastes to be used as cement replacement materials. The organic wastes explored in the research are rice husk ash (RHA), wheat straw ash (WSA), and cow dung (CDA). When the organic waste is turned into ash, it develops a pozzolanic character due to the presence of silica. However, the presence of reactive silica and its pozzolanic reactivity depends on the calcination temperature, duration, and grinding. In this research, the organic wastes were calcined at three different calcination temperatures (300 °C, 400 °C, and 800 °C) for 2, 4, 6, and 8 h duration. The obtained ashes were ground for 30 min and replaced by 20% with cement. The samples containing ashes were tested for compressive strength, X-ray diffractometry (XRD), weight loss, and strength activity index (SAI). It was observed that the RHA calcinated at 600 °C for 2 h showed better strength. However, in the case of WSA and CDA, the most favorable calcination condition in terms of strength development was obtained at 600 °C for 6 h duration. The highest SAI was achieved for the mortar samples containing CDA calcinated at 600 °C for 6 h duration (CDA600-6H). The other two ashes (RHA and WSA) did not qualify as pozzolan according to the ASTM C618 classification. This was due to the presence of silica in crystalline form and lower surface area of the ash material. In this research, the ash was ground only for 30 min after calcination which did not contribute to an increase in the specific surface area and thus the pozzolanic activity. The materials ground for the higher duration are recommended for higher SAI