Freeze‐Thaw Durability of Air‐Entrained Concrete

Huai-Shuai Shang,Ting-Hua Yi

doi:10.1155/2013/650791

Abstract

One of the most damaging actions affecting concrete is the abrupt temperature change (freeze-thaw cycles). The types of deterioration of concrete structures by cyclic freeze-thaw can be largely classified into surface scaling (characterized by the weight loss) and internal crack growth (characterized by the loss of dynamic modulus of elasticity). The present study explored the durability of concrete made with air-entraining agent subjected to 0, 100, 200, 300, and 400 cycles of freeze-thaw. The experimental study of C20, C25, C30, C40, and C50 air-entrained concrete specimens was completed according to “the test method of long-term and durability on ordinary concrete” GB/T 50082-2009. The dynamic modulus of elasticity and weight loss of specimens were measured after different cycles of freeze-thaw. The influence of freeze-thaw cycles on the relative dynamic modulus of elasticity and weight loss was analyzed. The findings showed that the dynamic modulus of elasticity and weight decreased as the freeze-thaw cycles were repeated. They revealed that the C30, C40, and C50 air-entrained concrete was still durable after 300 cycles of freeze-thaw according to the experimental results.

Highlights

Concrete is considered as one of the most nonhomogeneous and demanding engineering materials used by mankind
This paper presents experimental study on the relative dynamic modulus of elasticity and weight loss of C20, C25, C30, C40, and C50 air-entrained concretes after 0, 100, 200, 300, and 400 cycles of freeze-thaw according to “the test method of long-term and durability on ordinary concrete” GB/T50082-2009 [14]
Comparing the test results in this paper with the conclusion given by other authors [4, 5], the deceased percentage for the relative dynamic modulus of elasticity and weight loss of air-entrained concrete is less than that of plain concrete after the same cycles of freeze-thaw

Summary

Introduction

Concrete is considered as one of the most nonhomogeneous and demanding engineering materials used by mankind. The durability [1,2,3,4,5] of concrete is defined as the ability to withstand damaging effects of environment without deterioration for a certain period of time. Concrete has a potential to be damaged if it is subjected to freeze-thaw cycles. ACI defined cold weather as the period where more than three successive days have a mean daily air temperature less than 40 F (Fahrenheit). The freeze-thaw durability of concrete is of utmost importance in countries having subzero temperature conditions, such as The Arctic Zone, Russia, Northern China, and China. A progressive deterioration which starts from the surface separation or scaling and ends up with complete collapse, is a major concern when concrete is used in colder regions

Results

Discussion

Conclusion