Flexural strength, polymer impregnation

Steel fiber has been used to reinforce concrete. When 10-mil square bar 2 inches long is incorporated into concrete to the extent of 2% by volume, the modulus of rupture (flexural strength) increases by a factor of 2. When impregnated with polymer the fiber reinforced concrete-polymer increases the modulus of rupture by another factor of 2.5. Thus, an over-all increase by a factor of 5 in the flexural strength is achieved... 

Polymers. The purpose of adding polymers to the concrete matrix is to improve the characteristics of the fresh concrete (such as workability) and also to enhance the hardened properties such as flexural strength, modulus of elasticity and adhesive performance [8]. The incorporation of polymers into concrete may be in the form of polymer modified concrete (PMC), polymer impregnated concrete (PIC) or as polymer concrete (PC) [9], For this project, the objective was to develop an ultra-lightweight concrete material using Portland cement as the main binder modified with a suitable polymer - thus a PMC application. The polymer modifiers selected for the development of the ultra-lightweight thin filmed material were a commercially available SBR latex as well as a readily available acrylic polymer. 

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