Constructibility of Prestressed Concrete Panels for Use at Skewed Expansion Joints

The Texas Department of Transportation (TxDOT) has typically used a thickened, cast-in-place slab in lieu of any special supports or diaphragms at concrete bridge deck expansion joints for many years. A new detail to replace the thickened cast-in-place slab was developed was developed under TxDOT research project 0-44118. The standard prestressed panels typically used at interior portions of the bridge are continued to the expansion joints in zero degree skew bridge decks. The new detail improved construction speed, safety, and economy.

The primary goals of the research project reported here were to evaluate the feasibility of producing trapezoidal-shaped prestressed concrete panels as well as address construction related issues so that use of the new panel detail can be extended to include skewed expansion joints. A total of eight trapezoidal panels were fabricated using two different prestressing layouts and various geometries. In two panels, a flared prestressing strand pattern was used while in the other six panels, an arrangement with the prestressing strands parallel to the skewed end of the panel was used. A 45 degree skew angle was used in four of the panels and a 30 degree skew angle was used in the other four panels. A short edge length of 45 in. or 60 in. was used for the trapezoidal panels and all panels were 4 in. thick and 9 ft. 6 in. wide.

The results of the research project demonstrate that producing trapezoidal prestressed panels can be economical while accommodating a wide range of geometries. The research project showed that trapezoidal prestressed panels provide a feasible alternative to stay-in-place formwork at skewed expansion joints.