弯沉试验（Deflection test）.doc

弯沉试验（Deflection test） Using the Backman beam to determine pavement rebound deflection of simple operation, wide application, standard method of design and test of road pavement and basic parameters are established on the basis of this method, but this method of testing the whole testing process is manual operation, the test results influenced by human factors, and slow speed. The automatic deflection tester is an efficient automatic equipment for measuring the value of pavement deflection. It can measure the strength of the pavement with high density. It is suitable for the quality control and acceptance of pavement construction and pavement maintenance management. 1. main equipment Automatic deflectometer measuring car: Locke Lou Wa Ge, by testing cars, measuring institutions, data acquisition and processing system composed of three parts. The measuring mechanism is installed under the test vehicle chassis. The main technical parameters of the automatic deflectometer are as follows: Test car wheelbase: 6.57m Length of measuring arm: 1.75-2.40m Rear axle load: 100kN Measure the pressure of wheelset surface: 0.7MPa Minimum test step: 4-10m Test accuracy: 0.01mm Test speed: 1.5-4.0km/h 2. working principle The basic working principle of the automatic deflectometer is the same as that of Beckman Leung. Automatic determination of bending vehicle at a certain speed in the test section deflectometer will be installed in the test car, rear axle chassis below the deflection measuring beam to the front of the chassis of the vehicle is supported on the ground remained motionless, when the rear wheel gap through the measuring head, the deflection displacement sensor device is automatically recorded, then determination of beam is, drag, at two times the speed of car towed to the next point, rolling forward continuous determination. The computed results of section deflection detection can be output by computer. 3. use technical points (1) automatic deflection instrument for long