An end result specification for concrete airport pavements has been developed to reduce the likelihood of inadequate or potentially deleterious materials being incorporated in the work, and to improve the overall quality of construction. These quality objectives are enhanced through financial incentives tied to the key specification requirements of concrete strength and durability, pavement thickness and surface smoothness. The end result specification was implemented during the second phase reconstruction of a large concrete pavement apron area at a Canadian Forces airbase. This concrete had reached the end of its effective service life due to general structural cracking of slabs and alkali aggregate reactivity. The conventionally specified first phase reconstruction with a slipform paver was prone to edge slumping which resulted in roughness and surface drainage problems along longitudinal construction joints. The second phase reconstruction by the same contractor, with the new end result specification, provided a substantial improvement over the first phase in terms of consistency of pavement strength, thickness and smoothness. A performance bonus for overall pavement quality was achieved. No problems were experienced with the contractor's concrete mix design or slipform paving operations. In addition, increased confidence in the expectation of satisfactory concrete durability performance was achieved due to enhanced materials prequalification requirements. (A)
Samenvatting