Keywords: foam concrete

Eco-Friendly Foam Concrete with Improved Physical and Mechanical Properties, Modified with Fly Ash and Reinforced with Coconut Fibers

https://doi.org/10.58224/2618-7183-2025-8-1-1
Abstract
The development of new types of environmentally friendly and cost-effective building materials is currently a relevant topic and is actively developing throughout the world. In modern construction materials science, the most popular direction is the development of new concrete compositions using waste of various origins. The objective of this study is to develop new compositions of foam concrete using local waste from the fuel and energy complex and plant natural fibers. To determine the optimal amount of the modifying additive fly ash (FA), 7 experimental concrete compositions with different percentages of cement replacement by FA were made. The content was established as optimal. Foam concrete with 15% FA has the lowest density of 1075 kg/m3 and a minimum thermal conductivity coefficient of 0.248 W/m × °C, as well as increases in compressive and bending strength of 23.3% and 21.7%, respectively. The effect of coconut fiber (CF) was assessed on the composition of foam concrete modified with the optimal amount of FA 15%. The optimal dosage of CF was 0.6%. As a result of FA modification and CF dispersed reinforcement, a complex effect was obtained. The increase in compressive and bending strength was 30.14% and 72.83%, respectively, compared to conventional foam concrete. The density and thermal conductivity coefficient decreased by 9.8% and 8.34%, respectively. The results obtained during the experimental studies prove the effectiveness of the proposed formulation solutions and allow obtaining an energy-efficient foam concrete composite with improved characteristics.
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THE USE OF SEMI-AQUATIC CALCIUM SULFATE TO INTENSIFY THE PROCESSES OF HARDENING OF STRUCTURAL HEAT-INSULATING FOAMED CONCRETE

https://doi.org/10.34031/2618-7183-2018-1-3-25-32
Abstract
Construction of energy- and resource-saving housing of increased comfort involves the creation of more efficient building materials in comparison with traditional and new designs of fencing buildings with im-proved thermal properties. The problem of energy saving in construction has determined the direction of creation and production of effective cheap materials with high thermal properties. One of the most promising materials of this type is environmentally friendly, non-combustible cellular foam concrete.
The problem of accelerating the setting and hardening of foam concrete mixtures, as it allows to accelerate the turnover of forms and reduce the time from manufacturing to sending the finished product to the consumer is of great practical interest.
However, in most cases, domestic foaming agents are produced and used without additional input of setting and hardening regulators. This is due to the fact that the compatibility of the latter with the main additive – foaming agents is not sufficiently investigated. This problem is quite complex, as some setting accelerators can cause defoaming, worsen the structure of the foam matrix, reduce the mechanical strength of the stone and have other negative effects. At the same time, properly selected setting accelerators enhance the action of foaming agents
In the work the questions of application of semi-aqueous calcium sulphate (SCS) for intensification of hardening of foam concrete are considered. The change in physical and mechanical characteristics of foam concrete prepared on anionic and cationic blowing agents with an additional content of 1, 2 and 3% semi-aqueous calcium sulphate is shown. It is established that the SCC allows accelerating the hardening processes, and the formation of ettringite does not cause strong internal stresses, which is related to the porous structure of the material.
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