Equipment for obtaining pavement condition and traffic loading data

Equipment is identified that is associated with the collection of structural capacity, surface distress, friction, roughness, and traffic loading data. Current practices costs, and maintenance requirements are presented. Advantages and disadvantages of particular types of equipment are also presented and new equipment developments are briefly discussed. Currently, structural capacity is evaluated by a measure of surface deflection under a slow-moving, vibrating, or falling load. The Benkelman beam is the most commonly used equipment. Techniques for measuring physical distress and types of distress catalogued vary by agency and depend on the purpose for which the information is collected. Pavement surface friction is mostly measured with the locked-wheel-trailer procedure or the yaw mode procedure. Ride quality is related to the roughness of the pavement and is measured by either response-type equipment or profilometer. Equipment for collecting traffic volume and traffic weights are portable counters, fixed counters, weigh-in-motion devices, portable scales, and permanent weigh stations.