1. Continuously Reinforced Concrete Pavement
Pavement Engineering M. Kharabsheh

2. Pavement Engineering M. Kharabsheh

3. Factors that must be Considered by Pavement Engineer. Must Know
Short Slabs can be designed and load transfer is provided by Aggregate Interlock (Contraction Joint)
The crack or contraction joint can be tied with Tie Bars of distributed steel to prevent the crack or joint from opening
Movement at joints can be permitted (Expansion Joints) and Dowel Bars are placed at the Joints to provide load transfer.
Pavement Engineering M. Kharabsheh

4. Construction Joints with Tie Bars
Pavement Engineering M. Kharabsheh

5. Contraction joint showing saw cut depth
Pavement Engineering M. Kharabsheh

6. Aggregate Interlock (Contraction Joint)
Pavement Engineering M. Kharabsheh

7. Pavement Engineering M. Kharabsheh
(Contraction Joint)
Pavement Engineering M. Kharabsheh

8. Pavement Engineering M. Kharabsheh
(Contraction Joint)
Pavement Engineering M. Kharabsheh

9. Pavement Engineering M. Kharabsheh
(Expasion Joint)
Pavement Engineering M. Kharabsheh

10. Pavement Engineering M. Kharabsheh
Dowel Bars Storage
Pavement Engineering M. Kharabsheh

11. Dowel Bars Construction
Pavement Engineering M. Kharabsheh

12. Pavement Engineering M. Kharabsheh
Dowel Group Action
When traffic loads are applied at a joint, a portion of this load is transferred through the dowel bar into the next slab (this portion should be 50% for perfect load transfer)
The dowel bar immediately under the applied load bears a major portion of the load with other dowels assuming progressively lesser amount.
Pavement Engineering M. Kharabsheh

13. Pavement Engineering M. Kharabsheh
Dowel Group Action
Maximum negative moment occurs at a distance 1.8L from the load.
The dowel bar immediately under the applied load carries full capacity (one full unit) and the portion of each dowel decrease to reach zero at a distance of 1.8L.
The corner dowel is the critical one for the edge load.
Pavement Engineering M. Kharabsheh

14. Pavement Engineering M. Kharabsheh
Example
Load is 9000lb on each wheel
Assume 50% load transfer
Thickness= 10’ and Subgrade reaction = 50pci
Radius of relative Stiffness l = 51.1’ (from table 3.1 page 84)
Pavement Engineering M. Kharabsheh

15. Pavement Engineering M. Kharabsheh
Example
X1 = 1
1/92 = x2/(92-12) x2 = 0.87
Effective Dowels group for load at A = S xi = = 4.35
Total load carried by dowel
At point A = load from wheel
At A plus load from wheel at
Point B
Total load at A = 4500/(4.35*1)
+ 4500/(7.32*0.22) = = 1170 lb
Pavement Engineering M. Kharabsheh

16. Example on Bearing Stress by Dowel on Concrete
Pavement Engineering M. Kharabsheh

17. Pavement Engineering M. Kharabsheh

18. Pavement Engineering M. Kharabsheh