Premature deterioration of joints in concrete pavements is reportedly a problem in cold weather regions. Distress is often first observed as shadowing when microcracking near joints traps water followed by loss of materials around the joints. It is also seen as cracks parallel to the saw cut. Although not all pavements are distressed, the problem is common enough to warrant attention.;The goal of this study was to improve understanding of the mechanisms behind premature joint deterioration in concrete pavements. Objectives of this study were to (1) conduct laboratory freeze-thaw tests to investigate the effect of concrete interfacial zone to the deterioration, (2) evaluate the influence of pore structure of cement paste to the freeze-thaw durability using mercury intrusion porosimetry (MIP) tests, and (3) use of a borehole permeameter to conduct a field study to assess the influence of the permeability of subsurface layers on joint performance.;Laboratory freeze-thaw tests results revealed that the concrete interfacial zone likely contributes to the accelerated deterioration of concrete pavement joints. MIP tests results showed that hardened cement paste with a w/cm ratio typically used in pavements has a pore size distribution similar to that of aggregates prone to D-cracking. The field investigation showed that impermeable base layers are likely contributing to joint deterioration. The field investigation indicated that subsurface layers of concrete pavements in winter are significantly less permeable than in summer because when water that is trapped in the subsurface freezes, excess water cannot drain out of the pavement so increasing concrete saturation and so risk of freezing related damage. Both laboratory and field studies indicate that a combination of multiple factors (e.g., materials, design, and construction) causes the deterioration of concrete.
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