Agro Waste Sugarcane Bagasse as a Cementitious Material for Reactive Powder Concrete

In the field of advanced concrete science, the construction industry has risen to great heights. Due to its own characterisation, the manufacturing cost of reactive powder concrete (RPC) is very high. This can be minimised by substituting the components of the RPC with the aid of agro waste. Because of the production of sugar from the sugar cane industry, bagasse ash is abundantly available in India. It is not ideal for the direct replacement of ingredients in concrete because of the presence of carbon dioxide in bagasse ash. The study of bagasse ash’s actions under different temperatures and different exposure times is discussed in this paper. It is inferred from the findings obtained from the energy dispersive study of X-ray (EDAX) that the presence of reactive silica in bagasse ash could be substituted by RPC ingredients due to heat treatment. RPC is composed of exceptionally fine powders (cement, sand, quartz powder and silica smolder) and superplasticiser. The superplasticiser, utilised at its ideal dose, decreases the water to cement proportion (w/c) while enhancing the workability of the concrete. A thick matrix is accomplished by optimising the granular packing of the dry fine powders. This compactness gives RPC ultra-high quality and durability. Reactive powder concretes have compressive qualities extending from 200 to 800 MPa.

Development of the Compositional Binder for Cement-Concrete Used in Monolithic Construction

One of the urgent problems of modern concrete science is the use and improvement of high-quality concrete. The emergence of such concretes has opened a new era in construction. Their unique properties are: high strength and corrosion resistance, water resistance and frost resistance, adjustable deformability. High-quality concretes provide high guaranteed parameters of the operational reliability of buildings and structures under the conditions of complex environmental effects and loads, significantly reduce construction time and reduce investment risks. One of the promising materials that allows you to ensure all of the above characteristics is fine-grained concrete based on a composite binder.

CONCRETE COMPOSITES USING GRAND-SANDY MIXTURES OF DEPOSITS OF THE CHECHEN REPUBLIC

Objectives Development of optimal recipes of concrete mixtures using local natural raw materials in the form of gravel-sand mixtures from deposits of the Chechen Republic.Method The research methods adopted in the work are based on the theoretical principles and laws of designing and optimizing polydisperse multicomponent systems, the phase and structure formation of clinker minerals, the logic of mathematical calculations, the technological features of the structure formation of composite masses, the theoretical principles of controlling the rheological processes of mixes. All experimental data presented in the work were obtained according to the methods of current regulatory documents (GOST, recommendations, etc.).Result The paper presents the results of a study of the composition and properties of sand and gravel mixtures of deposits of the Chechen Republic and concretes based on them. In particular, the granulometric and chemical compositions and the physicomechanical properties of sand and gravel mixtures have been studied. An analysis of the scientific literature and experience in the use of sand and gravel in construction. The leading scientific schools of the country and abroad in the field of concrete science are presented. The rheological indices of concrete mixes were studied and the dynamics of the curing of concrete of different classes were obtained on the basis of unfortified sand and gravel mixtures in the presence of a chemical additive, the superplasticizer Polyplast SP-1.Conclusion It is proposed to use sand-gravel in its natural form in concrete for non-critical structures in its natural form without additional costs for enriching its composition. The feasibility of obtaining low-grade concrete with the use of sand and gravel mixtures without its enrichment and fractionation is established.

Theoretical Prerequisites for Strengthening Micro-Structure of Surface Layer in Road Concrete Pavement by Colloid Material

Assuming that there are perpetual roads solution of the problem pertaining to strength and longevity of road concrete pavements are mainly determined by theoretical prerequisites which are considered as basic ones in technology for strengthening micro-structure of their top surface layer. Application of fine grain concrete with ultra-disperse additives partially helps to obtained strengthened top layer of such pavements. At the same time further search and improvement of theoretical analysis for the given problem are required for development of technological parameters. Investigations on this direction are rather insignificant and the problem continues to be considered as an actual one. There is a known method for application of colloid cement glue and activated gunite solution for strengthening binding of new and old concrete in engineering structures. However it is necessary to point out the fact that investigations in the field of protection of road concrete pavements against corrosion destructions are actually absent. Such approach restrains a wide application of the mentioned methods in engineering practice for provision of efficient maintenance of concrete pavements. In this case it is necessary to consider the existing theoretical statements on the essence of quantum structure-formation mechanics in the systems consisting of colloid-disperse particles. This approach to road concrete science is accepted a new one ant it is connected with the possibility to regulate processes of structure-formation micro-mechanics in mineral systems while creating protective surface layers in road concrete pavements. The given paper is devoted to this problem.