Upcoming Projects

The following are a list of current applied research needs related to concrete pavement airfields. This is only a partial list and is subject to change through discussion with the ACPTP program coordination group and/or technical advisory committee.

ACPTP- Limestone Cements

PLC cements are becoming the norm in many locations, with Type I or Type II cements no longer available. A review is needed to evaluate the potential effects of these changes on airfield specifications and performance.

ACPTP- Load Transfer in Concrete Pavement

Current FAA and Department of Defense standards for airfield pavement are designed for aggregate interlock to provide for load transfer in contraction control joints except for the last three joints at the end of a feature or adjacent to an isolation joint. The thinking is that aggregate interlock will provide for at least the design assumption for load transfer, which is assumed to be 25 percent. However, many engineers question if this assumption is valid during concrete contraction in cold weather or after numerous expansion and contraction cycles. The question remains if the dowels provide increased load transfer efficiency and if they do, does it increase pavement performance enough to justify the increased cost of construction. Applied research is needed to assess the performance and value of dowelled versus un-dowelled contraction joints.

ACPTP- Start/Stop Practices

There are mixed opinions regarding whether it is preferable to start/stop a paving machine or to slow it down if concrete deliveries are insufficient. Guidance is needed to assist contractors and inspectors on how smoothness can be best maintained under varying conditions with regard to materials delivery.