Blowups: Still a Problem?

BLOWUPS OF PORTLAND CEMENT CONCRETE PAVEMENTS HAVE BEEN A PROBLEM ENCOUNTERED BY THE INDIANA STATE HIGHWAY COMMISSION AND MANY OTHER HIGHWAY DEPARTMENTS FOR MANY YEARS. THIS REPORT, AFTER BRIEFLY DEFINING BLOWUPS AND GIVING A SHORT HISTORY OF THE DESIGN OF CONCRETE PAVEMENTS IN INDIANA, PROCEEDS WITH A DISCUSSION OF THE FACTORS INFLUENCING BLOWUP OCCURRENCE, AMONG WHICH ARE THE FOLLOWING: (1) CLIMATE (TEMPERATURE AND MOISTURE CONTENT OF THE SLAB); (2) TYPE AND NUMBER OF THE JOINTS; (3) AGE OF THE PAVEMENT; (4) TYPE OF AGGREGATE USED IN THE CONCRETE; (5) TYPE OF SUBGRADE; (6) SUBBASE (TYPE AND PERMEABILITY, AND USE OF DRAINS); (7) TRAFFIC; (8) SUBBASE (TYPE AND FREQUENCY--PRIMARILY JOINT SEALING); (9) PAVEMENT THICKNESS; AND (10) TYPE OF SHOULDERS. IN CONCLUSION THE OBJECTIVES OF A PROJECT FORMULATED UNDER THE SUPERVISION OF THE JOINT HIGHWAY RESEARCH PROJECT AT PURDUE UNIVERSITY TO INVESTIGAGE BLOWUPS IN RESURFACED PAVEMENTS ARE PRESENTED.