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Uncontrolled mining and the tailings produced can cause significant environmental impacts such as water, air, and soil pollution. In the present study, a contaminated soil of gold mines located in the Karnataka state of India was studied to know the geotechnical behavior of this soil as a foundation material and to suggest a suitable soil remediation technique to avoid contamination of surrounding water bodies. The in-situ dry unit weight of soil at the selected locations varied from 15.71 to 18.75 kN/m 3 . The effective shear strength parameters determined from Triaxial test results were in the range of 4.8 -8.2 kN/m 2 and 19.4 0 -29.8 0 , respectively, for the cohesion and angle of internal friction. The soil samples were analyzed for bearing capacity and settlement using GEO5 software tool, and the economical dimensions of the footings were estimated. It was observed that the soil has sufficient bearing capacity, and the settlements are within the allowable range. The chemical analysis of the soil samples showed that there are considerable amounts of heavy metals present in the mine soil. Though the strength of the soil is good, the contaminants in the soil may cause groundwater contamination and damages to the footings. Hence, the soil washing technique as a remediation technique was also studied through column leaching tests using different leaching solutions and found that diluted hydrochloric acid (HCl) with Ethylenediamine-tetraacetic acid (EDTA) can effectively remove the heavy metals from the soil.

This examination is engaged into assessing the clasping heap of isotropic and overlaid plates (15 o /3o o /45 o /6o o ) which is exposed to in plane pressure. The investigation device utilized for this intention was ANSYS 19.0. The clasping load is assessed by changing the parameters, for example, angle proportion (a/b), thickness proportion (S) and limit conditions. It was noticed that diverse length to broadness proportion influenced the basic clasping load and the fiber direction edges likewise influenced the basic clasping load symmetric point employ plates.

The present study focused to improve material characteristics and quality in terms of the NaOH concentration for treating the coconut and bamboo fiber to enhance the mechanical properties of natural fiber polymer-based hybrid composites. The NaOH-treated fibers were washed thoroughly using distilled water and allowed to dry for 24 hours. Composition of each specimen, bamboo (B) and coconut (C) fiber with epoxy composite, was prepared by hand layup process as per the American Society for Testing and Materials (ASTM) standard. The proportionality of the material was carefully fulfilled according to the previous literature reports. The weight fraction of the composite material content was set to be 30% and 70% of epoxy (E) resin and isolated fibers. Three distinct criteria were used to calculate mechanical parameters such as tensile strength, flexural strength, and material hardness. It was found that the combination of 70% E with 30% BC of hybridized composite had a maximum tensile strength of 62.42 MPa, whereas the flexural strength and hardness of the other combinations, such as 70% E with 30% C and 70% E with 30% B, were observed to be 58 MPa and 185 HRC (Hardness Rockwell C), respectively.

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The mechanical performance of concrete with varying proportions of steel scraps as a composite additive is investigated in this work. A M50 grade concrete admixture with a 0.35 water-to-binder ratio was prepared for this study. The appropriate quantity of superplasticizer was included as the mineral admixture. Steel scraps are obtained as waste from local machining workshops and then included in various proportions, including 0.25, 0.5, 1.0, and 2.0 percentages. The cubical mortar specimens were being employed to determine the compressive characteristics of mortar structure with and without steel scrap, whilst the cylinder-formed specimens and beam shaped samples were being utilized to determine the indirect tensile strength and flexural strength of concrete mixture. All experiments with different percentages of steel scrap were conducted on the 3 replicates, and the mean value is provided in this paper. After 28 days, the cement without steel scrap seemed to have a mean compression, flexural, and tensile strengths of 46.3 MPa, 5.52 MPa, and 4.23 MPa, respectively, which were improved to 51.7 MPa, 6.16 MPa, and 4.58 MPa with the inclusion of 1.0% steel scrap. The proposed investigation will contribute to reducing cement use, hence reducing cement industry's adverse ecological impacts.

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