Severe spalling and half-depth punchout failures associated with horizontal cracks at the mid-depth of the concrete slabs were observed in continuously reinforced concrete pavement (CRCP) in Texas. A study was conducted to identify the causes of those horizontal cracks and their effect on pavement distress. Two types of horizontal cracks were observed. One is due to cold joints that might form when the double strike off method is used. The other is due to environmental loading such as temperature variations through the depth of slab. Mechanistic analysis shows that substantial shear stress and normal tensile stress in the vertical direction could develop at the mid-depth of concrete slab due to environmental loading. Concrete material properties such as modulus of elasticity and thermal coefficient have significant effects on those stresses. Evaluations of in-situ concrete material properties from sections with and without horizontal cracks and environmental conditions during construction all support the results of mechanistic analysis. Concrete shear strength at early ages was evaluated and, based on the stress analysis, it can be easily exceeded by shear stress at mid-depth, resulting in horizontal cracks.
|Number of pages||10|
|State||Published - 2002|
|Event||27th International Air Transport Conference - Orlando, FL, United States|
Duration: Jun 30 2002 → Jul 3 2002
|Conference||27th International Air Transport Conference|
|Period||06/30/02 → 07/3/02|