Evaluation of dowel bars wrapped with polyethylene sheet by measuring the volumetric change of slaband joint width measurement at early age of concrete

• Main Authors: Bronuela, Lea, Woo, Ryu SUng, Yoon, Ho-Cho
• Format: text
• Published: Animo Repository 2014
• Subjects: Bars (Engineering)—Dynamic testing; Bars (Engineering)—Testing; Polyethylene; Civil Engineering
• Online Access: https://animorepository.dlsu.edu.ph/faculty_research/6633
• Institution: De La Salle University

Dowel bars are mainly designed for traffic loading. Its main function is to transfer the load acquired from a loaded slab to its adjacent slab to avoid distress such as faulting or roughness issues. Faulting can lead to spalling or chipping of concrete slab edges at joint cracks. It maintains pavement serviceability and occurrence of distress. Likewise, environmental loadings such as temperature and humidity also affects the performance of dowel bar. When temperature increases, joins closes due to the expansion of concrete, while cold temperature generates larger joint width due to contraction of concrete. These movements on concrete along the surface of the dowel bars also induce stress and lead to distress at the joints. If movement of interface between concrete and dowel bar is restricted due to strong bond between concrete and dowel bars, crack forms along the concrete and eventually progress to formation of voids. This void may significantly affect the load transfer efficiency enhancement of steel dowel bar by measuring the movement of concrete at the joint due to volumetric change cause by environmental loading. Movement of concrete at a different curling condition was evaluated by strain measurement and actual displacement of joint width. The data shows that the wrapped of polyethylene sheet around the dowel bars allows movement of concrete than the typical type of dowel bar at early age of concrete.