Title:
Effects of Freezing and Thawing on the Tension Properties of High-Strength Concrete
Author(s):
H. Marzouk and Kajiu Jiang
Publication:
Materials Journal
Volume:
91
Issue:
6
Appears on pages(s):
577-586
Keywords:
dynamic modulus of elasticity; energy; flexural strength; freeze-thaw durability; resonant frequency; tension; Materials Research
DOI:
10.14359/1378
Date:
11/1/1995
Abstract:
Freeze-thaw cycles pose a serious problem for concrete structures in cold environments. This investigation deals with the exposure of high-strength concrete to rapid freezing and thawing in a controlled environment. Experimental tests consisted of measuring the relative dynamic modulus of elasticity, modulus of rupture, direct tensile strength, and change in mass of air-entrained concrete specimens. The tests were conducted on 20 x 75 x 300-mm and 75 x 75 x 350-mm prisms for both high-strength concrete (70 MPa) and normal strength concrete (40 MPa) at intervals of every 100 cycles up to 700 cycles. Test results revealed that high-strength concrete was still durable after 700 cycles of freezing and thawing in accordance with ASTM C 666. After 700 cycles, standard 75 x 75 x 350-mm prisms of high-strength concrete showed a reduction in mass of less than 1 percent, reduction in compressive strength between 10 to 15 percent, and reduction in modulus of rupture up to 15 percent. For the thin concrete 20 x 75 x 300-mm specimens used for the direct tension tests, the direct tensile strength was reduced between 15 to 25 percent. The post-cracking behavior of high-strength concrete after 700 cycles of freezing and thawing was evaluated in terms of the stress-strain curve and fracture energy. Specimens of normal strength concrete were used as reference specimens. The normal strength concrete prisms had deteriorated severely after 250 to 300 cycles. For the thin concrete specimens, the average value of the relative dynamic modulus of elasticity based on resonant frequencies at 300, 600, and 700 cycles was 72, 54, and 39 percent, respectively, compared with the corresponding values of 82, 69, and 66 percent, respectively, for high-strength concrete.