MAINTENANCE METHODS FOR PREVENTING AND CORRECTING THE PUMPING ACTION OF CONCRETE PAVEMENT SLABS - MISSOURI

SLAB PUMPING, OR THE DEFLECTION OF THE PAVEMENT UNDER A MOVING LOAD, IS THE EJECTION OF WATER THROUGH THE JOINTS AND CRACKS IN CONCRETE PAVEMENTS, CARRYING SOIL PARTICLES FROM THE SUBGRADE. IT RESULTS IN VOIDS UNDER THE PAVEMENT AND FINALLY BREAKDOWN OF THE PAVEMENT ITSELF. ELIMINATION OF ONE OR MORE OF THE FOLLOWING FACTORS RESPONSIBLE FOR SLAB PUMPING WOULD EXTEND THE LIFE OF CONCRETE PAVEMENTS: (1) HEAVY AXLE LOADS; (2) JOINTS OR CRACKS IN THE PAVEMENT; (3) UNSUITABLE SUBGRADE SOIL; (4) FREE WATER UNDER THE SLAB. METHODS FOR COMBATTING THESE PROBLEMS TO PREVENT OR CORRECT PAVEMENT PUMPING ARE EXAMINED.