Early Cracking Resistance of Basalt Fiber Bridge Deck Concrete in Hot and Humid Environment
摘要
Aiming at the problems of cracking and the durability reduction in hot and humid areas of southern China, basalt fibers were selected as concrete reinforcement materials. In simulated standard, hot, and humid curing environments indoors, the plastic shrinkage test, drying shrinkage test, humidity distribution test and circular ring restrained test were designed to explore the early cracking behavior of basalt fiber bridge deck concrete in hot and humid environment. The results showed that plastic cracking of basalt fiber bridge concrete was restrained in hot and humid environment. Compared with the reference concrete, its total cracking area per unit area was significantly reduced by 76.5%. The change of relative humidity in basalt fiber bridge deck concrete was the driving force for its development of drying shrinkage deformation. The decrease of relative humidity in the concrete slab could be slowed down by adding fiber, so as to inhibit its drying shrinkage cracking. The 28 d drying shrinkage deformation at the center and corner of the fiber reinforced concrete slab was 27.5% and 25.5% lower than that of the reference concrete. Besides, the incorporation of basalt fibers could inhibit the restrain cracking of concrete rings and improve cracking resistance of concrete.