Aggregate concrete, influence

Aggregate type influences expansion and shrinkage characteristics of concrete. Use of aggregates of high elastic modulus results in larger expansion [80]. 

The following is a list of recommendations that builders can use to utilize the foundation as a mechanical barrier to radon entry. Foundation walls and floor slabs are often constructed of poured concrete. Plastic shrinkage, and therefore cracking, is a natural function of the drying process of concrete. Many factors, such as the water/cement/aggregate ratio, humidity, and temperature, influence the amount of cracking that occurs in a poured concrete foundation. Cracking may be minimized by... 

Tishmack, J. K., Olek, J. Diamond, S. 1999. Characterization of high-calcium fly ashes and their potential influence on ettringite formation in cementitious systems. Cement, Concrete, and Aggregates, 21, 82-92. 

In the first part of this chapter we examine the influence of grain distribution, grain form, and basicity of aggregates on the strength of sulfur concrete. 

This test method was proposed by Senbetta16. Its original purpose was to evaluate the impact resistance of floor materials in terms of the capacity to resist surface disintegration due to repetitive low level impact. Instead of floor materials, this test was employed to measure the influence of plastic fillers on the concrete resistance to repetitive low impact. The specimens which were used in the test were nine 2-in. (50-mm) concrete cubes made with mix No. 2. The test uses the Los Angeles (LA) abrasion machine, which is traditionally utihzed to test aggregates according to ASTM C 131 and C 535 specifications. 

Different factors, such as the reinforcement ratio, size, and form of fibers, and the particle size of a coarse aggregate, exert a great action on the mechanical properties of a continuously reinforced concrete. The influence of these parameters... 

Potapov, Yu., Borisov, Yu., Panfilov, D., Figovsky, O., and Beilin, D. Research of Polymer Concrete Based on Low Molecular Polybutadiene, Part VI Influence of Particle Size of Coarse Aggregates and Reinforcement Ratio on the Fibrous Polymer Concrete Strength, J. Scientific Israel Technological Advantages 6, no. 3-4 (2004) 67-70. 

The properties of an aggregate influence both the characteristics of the fresh mix and the strength and durability of the hardened concrete. 

The ratio between clay-sized and silt-sized particles (less than 2 pm, and 2 to 75 pm, respectively) can influence the properties of the concrete [8.1]. Fines can have two detrimental effects. They may coat the surface of the aggregate, thereby weakening the bond between the matrix and the aggregate. They also tend to increase the water demand at constant workability. Both effects tend to reduce the strength of the hardened concrete. 

Concrete is formed by mixing cement, coarse and fine aggregate, water and possibly by the incorporation of admixtures [1-4]. Selection of the constituents is the first step for obtaining durable concrete, as their properties influence the behaviour... 

The porosity of the mineral that constitutes the aggregate influences the physical properties (especially density and water absorption), strength and elastic modulus of the concrete. These properties of aggregates are essential for concrete technology, and are dealt with in specialised literature [1,4]. 

Cramer SM, Carpenter AJ (1999) Influence of total aggregate gradation on freeze-thaw durability and other performance measures of paving concrete. Transp Res Rec 1668 1... 

In general, latex-modified mortar and concrete show a noticeable increase in the tensile and flexural strengths but no improvement in the compressive strength as compared to ordinary cement mortar and concrete. This is interpreted in terms of the contribution of high tensile strength by the polymer itself and an overall improvement in cement-aggregate bond. The strength properties of the latex-modified mortar and concrete are influenced by various factors which tend to interact with each other. The main factors... 

In general, the coefficient of thermal expansion of latex-modified mortar and concrete is directly influenced by that of the aggregates used, as in ordinary cement mortar and concrete. Latex-modified mortar and concrete usually have coefficients of thermal expansion equal to or slightly larger than that of ordinary mortar and concrete. Table 4.6l gives the coefficient of linear thermal expansion of SBR- and PVDC-modified mortars with variation of polymer-cement ratio. 

W.A. Tasong, C.J. Lynsdale and J.C. Cripps Aggregate-cement Paste Interface Part I. Influence of Aggregate Geochemistry, Cement and Concrete Research Vol. 29 (1999), p. 1019-1025. 

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