Which statement is true for the spacing of contraction joints in cement concrete pavement?
1
In unreinforced slabs, the maximum spacing of contraction joint can be 4.5 m
2
In reinforced slab, the spacing may be 13 m for 15 cm thick slab with steel reinforcement of 3.8 kg/cm2
3
In reinforced slab, the spacing may be 14 m for 20 cm thick slab with steel reinforcement of 2.7 kg/cm2
4
All of the above