Crack resistance of concrete

Experimental Research Methods and Machinery of Crack Resistance of Concrete... 

Figovsky, O., Karchevsky, V., and Beilin, D. Crack-Resistance of Concrete Elements with Polymer Coating, Proceedings of the Ninth Annual International Conference on Composite Engineering, ICCE/9, San Diego, CA, 2002, 369-370. 

CRACKING RESISTANCE OF CONCRETES WITH DIFFERENT STRUCTURURAL HETEROGENEITY... 

The main thrust of the present paper is that different characteristics of cracking resistance of concrete must be used at the various stages of crack initiation and growth. The authors have tried to answer the question - how do these characteristics depend on relative content and grain size of aggregates at constant mechanical properties of hardened cement paste (hep) matrix. 

Source Reprinted from O. Figovsky, D. Beilin, and Yu. Zemlyanushnov, Fracture and Crack Resistance of Silicate Polymer Concrete, Journal Scientific Israel Technology Advanced 14, no. 4 (2012) 38-48. With Permission. 

Fracture and Crack Resistance of Silicate Polymer Concrete [6]... 

As a rule, crack resistance of coarse aggregate concrete is determined by nonequilibrium mechanical testing using samples with a cut that initiates a crack. Nonequilibrium tests are characterized by loss of the deformation process stability of the sample during the moment of strain localization at the maximum load, with corresponding dynamic development of the main crack [14], However, such tests conflict with the condition in Equation (3.11), since in these concretes the size of the prefracture zone is 100-300 mm. 

Thus, modern methods of nonequilibrium mechanical tests do not allow identification of deformation and fracture conditions of concrete samples, which leads to an ambiguous evaluation of structural material properties, in particular, the crack resistance of a concrete. 

FIGURE 3.9 Test machine for equilibrium testing. (1) Test sample with initiated cut, (2) elastic steel ring, (3) punch, (4) distributive patch, (5) base, (6) press. (Reprinted from O. Figovsky, D. Beilin, and Yu. Zemlyanushnov, Fracture and Crack Resistance of Silicate Polymer Concrete, Journal Scientific Israel Technology Advanced 14, no. 4 (2012) 38-48. With Permission.)... 

Thus, the process of increasing the strength and crack resistance of silica polymer concrete after introduction of monomer additives to its composition is determined by the increase of the energy spent for the development of microcracks, elastic deformation, and the resistance of concrete to local deformation. 

Samples of two types were made Type KB (crack-resistant) for concrete and ceramic substrates, and type KM (anticorrosive) for metal and other substrates. Three series of various color samples (white, yellow, and green) were submitted on three substrate samples in each test series. All samples had a rectangular form, and measured 120 x 120 x 0.5 mm in size. Samples were fixed on a contour in special stainless steel frames, and used an aluminum substrate with a thickness of 0.635 mm. Samples were exposed in a vertical orientation. 

The crack resistance of the optimum coating composition of a concrete substrate was 2.0-2.5 mm in extension. Elongation of the coating before the moment of its fracture was determined as... 

Potapov, Yu., Borisov, Yu., Surovtsev, I., Figovsky, O., and Beilin, D. Increasing Repair and Crack Resistance of Reinforced Concrete Structures by Polymer Composites, Proceedings of the Second International Conference on Concrete Repair, Concrete Solution, St. Malo, France, 2006, 111-114. 

Li, G. (2014) A rutting and cracking resistance asphalt concrete. Technology Disclosure Form (OIP number 1422). Office of InteUecmal Property, Commercialization Development, Louisiana State University. 

The addition of microsilica generally improves the frost resistance of concrete. However, at higher microsiUca additions the reduced permeability of the material may hamper moisture migration, and may cause a build-up of internal hydraulic pressure and cracking. To prevent this the amount of added microsiUca must not be excessively high. The use of an air-entraining admixture may also be necessary, to provide an adequate air-void system. 

Czarnecki, L., Grabowski, L., Criterion of cracking resistance of glass fiber reinforced resins Proceedings of the International Symposium, ISAP 86, Adhesion between Polymers and Concrete, RILEM TC-52, Aix-en-Provence, France, Chapman and Hall, London, New York, 1986,... 

N. Banthia and N. Nandakumar, Crack growth resistance of concrete reinforced with low volume fractions of polymeric fiber , Journai of Materiais Science Letters 20, 2001,1651-1653. 

At Qatar, the liquid came out with such force that it spilled over the dike wall. Conventional dike walls also have the disadvantage that a large area of liquid is exposed to the atmosphere if a leak occurs. For these reasons it is now usual to surround cryogenic storage tanks with a concrete wall, about 1 m from the tank and the full height of the tank. If the tank is not made from crack-resistant material, then the concrete wall should be designed to withstand the effects of a sudden release of liquid. 

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