Characteristics of High - Strength Concrete up to 18 Ksi
نویسندگان
چکیده
This paper presents the results of a fundamental study to expand the applicability of the current AASHTO LRFD Bridge Design Specifications for concrete strength up to 18 ksi for reinforced and prestressed concrete members in flexure and compression. A total of 321 specimens were tested to determine the material properties of three high-strength concrete mixtures having target compressive concrete strengths of 10, 14, and 18 ksi. These material properties include compressive strength, elastic modulus, Poisson’s Ratio, modulus of rupture, creep and shrinkage. The study examined the effect of curing beyond 7 days compared to heat curing for one day and moist curing for 7 days only. The results indicate that the equation specified by ACI 363R-92 provided a good estimate of the elastic modulus. The average Poisson’s ratio for high-strength concrete is within the range generally assumed for normal-strength concrete. The equation specified by ACI 318-05 provided a more reasonable estimate of modulus of rupture. Creep of highstrength concrete is considerably less compared to normal-strength concrete, while the shrinkage values for high-strength concrete are comparable to those of normal-strength concrete.
منابع مشابه
Mertol, Rizkalla, Zia and Mirmiran 2006 CBC 1 FLEXURAL DESIGN USING HIGH-STRENGTH CONCRETE UP TO 20 KSI
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