Stress-Strain Relationship, Modulus of Elasticity and Ductility

2 Stress-Strain Relationship, Modulus of Elasticity and Ductility 

Latex-modified mortar and concrete contain polymers (modulus of elasticity, 0.001-10 x lO kgf/cm ) with considerably smaller modulus of elasticity compared to cement hydrates (modulus of elasticity, 10 30 x 10 kg cm ). Consequently, their deformation behavior and ductil ity (or extensibility) can differ to a great extent from those of ordinary cement mortar and concrete. Most latex-modified mortars and concretes provide a higher deformation, ductility (or extensibility), and elasticity than ordinary cement mortar and concrete, dieir magnitude depending on polymer type and polymer-cement ratio. 

The modulus of elasticity in compression and Poisson s ratio of latex-modified concretes are listed in Table 4.5. [ 1 The modulus of elasticity generally tends to decrease with a rise in the polymer-cement ratio. The Poisson s ratio of PAE- and SBR-modified concretes is nearly equal to that of unmodified concrete regardless of the polymer-cement ratio, but that of PVAC-modified concretes increases with rising polymer-cement ratio. 

COMPRESSIVE STRAIN xIO COMPRESSIVE STRAIN,xIO COMPRESSIVE STRAIN, xlO- S -MOofFlIb PAE-MODIRED MORTAR EVA-MODIFIED MORTAR 

TVpe of Concrete Polymer-Cement Ratio (%) Modulus of Elasticity in Compression (xlO kgf/cm ) Poisson s Ratio 

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