TESTING AND EVALUATION OF LARGE, OFF-HIGHWAY HAULAGE TRUCK BRAKE SYSTEMS.

Performance requirements of service brakes for large off-highway haulage trucks have recently been questioned, particularly for downgrade hauls as experienced in many Western mining operations. Underwood McLellan & Associates Limited, Consulting Engineers, has been engaged in a program of testing and evaluating the performance of several types and sizes of brakes which are commercially available to the industry. Unique procedures were developed to acquire performance data at high levels of energy input to the brakes of trucks having GVW's in the order of 350,000 to 550,000 pounds. This paper describes the background and development of the test program and procedures, the testing details, the method of data evaluation, and a summary of performance characteristics as deduced from the test data analysis.