Which of the following statements is/are true corresponding to the design of rigid pavements?
1
Warping stress in cement concrete pavements is caused by the seasonal variation in temperature.
2
During day time the temperature stress at the interior or edge is tensile at the bottom.
3
Frictional stresses are maximum at the center and zero at corners.
4
At interior in day time at the bottom, critical condition or worst combination of stresses is during winter.