Jointed plain concrete pavement (JPCP, Figure 1) uses contraction joints to control cracking and does not use any reinforcing steel. Transverse joint spacing is selected such that temperature and moisture stresses do not produce intermediate cracking between joints. This typically results in a spacing no longer than about 6.1 m (20 ft.). Dowel bars are typically used at transverse joints to assist in load transfer. Tie bars are typically used at longitudinal joints.
Properties
Crack Control
- Contraction joints, both transverse and longitudinal
Joint Spacing
- Typically between 3.7 m (12 ft.) and 6.1 m (20 ft.). Due to the nature of concrete, slabs longer than about 6.1 m (20 ft.) will usually crack in the middle. Depending upon environment and materials slabs shorter than this may also crack in the middle.
Reinforcing Steel
- None.
Load Transfer
- Aggregate interlock and dowel bars. For low-volume roads aggregate interlock is often adequate. However, high-volume roads generally require dowel bars in each transverse joint to prevent excessive faulting.
Other Info
- A majority of U.S. State DOTs build JPCP because of its simplicity and proven performance.