This paper deals with the experimental studies conducted on the effects of using sea sand on the properties of polymer concrete modified using epoxy resin. The physical properties including workability, mechanical properties, and durability properties were evaluated as a function of sea-sand substitution. The results obtained behave as strong evidence for the feasibility of using sea sand as fine aggregate to solve the problem associated with the exhaustion of natural aggregates when used in combination with epoxy polymer. A clear understanding of the behavior of polymer concrete with sea sand as aggregate was obtained through some preliminary investigations. The test results showed a significant improvement in the compressive and flexural strength due to the sea-sand substitution in polymer concrete. Resistance to the water intrusion was also improved for the concrete mixes due to the inclusion of epoxy resin. The quality and the integrity of the concrete were also improved, as evident from the SEM analysis and infrared (IR) spectroscopy, and the results function as solid basis for the use of sea-sand polymer-modified concrete for practical applications. Results also show that 15% replacement of fine aggregate by sea sand in air-cured polymer concrete exhibited enhanced strength and durability properties; thus, the produced concrete can be an effective material for unreinforced concrete applications.

The aim of this paper is to study experimentally the effect of marble powder and green sand as partial substitute for fine aggregate on the strength and durability of M40 grade concrete. The use of metakaolin as a pozzolanic admixture by using as binder replacement is also studied to assess the properties with respect to fresh and hardened state. Several formulations were prepared with constant water-binder ratio 0.4 and varying percentages of marble powder and green sand. The results indicated that the properties of concrete were much enhanced by extent incorporation of marble powder and green sand as fine aggregate and metakaolin for cement when compared to normal concrete. The microscopic studies also confirmed the viability of using green sand and marble powder as fine aggregates.

This research aims to combine the effects of nanosilica and glass powder on the properties of self-compacting mortar at normal and at higher temperatures. The fine aggregate was replaced by waste glass powder at various percentage levels of 10%, 20%, 30%, 40% and 50%. The mechanical properties of self-compacting glass mortar (SGCM) were studied at elevated temperatures of 200, 400, 600 and 800 °C. Furthermore the effect of sudden and gradual cooling technique on the residual strength of glass mortar was also investigated In order to enhance the behavior of SCGM the nanosilica of 3% by weight of cement was added. From the results it was obtained that the glass powder replacement effectively contributed towards the thermal performance while the addition of nanosilica enhanced the mechanical performance. The enhanced physical properties were obtained mainly at the glass transition temperature thus showing the active participation of glass powders during high temperatures. Moreover the gradually cooled specimens exhibited improved strength characteristics than the suddenly cooled specimens.