Tie Bars in Concrete Pavement

Tie bars are steel bars that are used to connect adjacent concrete pavement slabs. The purpose of tie bars is to transfer loads and prevent differential vertical movement between adjacent slabs. Tie bars also help to maintain the longitudinal alignment of the pavement and prevent the formation of cracks.

Location of Tie Bars

Tie bars are typically provided in the longitudinal joints of concrete pavement. Longitudinal joints are the joints that run parallel to the direction of traffic flow. The reason for providing tie bars in longitudinal joints is that these joints are subjected to the highest amount of stress and strain due to traffic loads.

Types of Joints in Concrete Pavement

There are four types of joints in concrete pavement:

1. Contraction joints: These joints are provided at regular intervals to control cracking due to shrinkage of concrete as it dries and hardens.

2. Expansion joints: These joints are provided to allow for the expansion of concrete due to temperature changes. Expansion joints are typically filled with compressible materials such as asphalt impregnated fiberboard.

3. Longitudinal joints: These joints are provided to separate adjacent pavement slabs and allow for differential horizontal movement. Longitudinal joints are typically sawed or formed.

4. Construction joints: These joints are provided to separate different placements of concrete. Construction joints are typically formed by placing a keyway or dowel into the previously placed concrete.

Conclusion

In summary, tie bars are provided in the longitudinal joints of concrete pavement to transfer loads, prevent differential vertical movement, and maintain pavement alignment. Longitudinal joints are the joints that run parallel to the direction of traffic flow and are subjected to the highest amount of stress and strain due to traffic loads.