EXTERNAL METHODS FOR EVALUATING SHOCK ABSORBERS FOR ROAD ROUGHNESS MEASUREMENTS

Two new experimental methods are described for the selection of shock absorbers for response-type road roughness meters. The methods allow for verification of the acceptability of the shock absorbers before they are mounted in the road roughness measuring vehicle. In the first method, a programmable shaker table is used to obtain the time response of the shock absorber. In the second method, a simple scotch yoke mechanism is used to produce the frequency response of the shock absorber. In both methods, the test results are compared with the corresponding time domain or frequency domain acceptability limits, which are determined from computer simulation and based on the relevant ASTM standards.