Vehicle Weigh-In-Motion Research Based On Embedded Piezoelectric Ceramic Sensor

It's becoming increasingly common for the vehicles to overload on roads for the past several years, which led to great economic losses of our country. The overloading transportation severely reduces the service life, easily causes traffic accidents and has an extremely negative effect on the transportation market. Thus it is of great necessity to restrict this phenomenon by developing a mature dynamic weighting technology for vehicles. Although the exiting dynamic weighting technology has the advantages of high accuracy and multiple functions, this technology is mostly applied to highways rather than ordinary roads due to the long construction period, large reconstruction on the pavement and high cost that are needed for using it. This paper proposes an economic-effective Weigh-In-Motion system for vehicles by applying embedded piezoelectric ceramic sensor which requires little reconstruction on road surface, low cost and with high precision, so it could be easily generalized among low-level pavements. The main aspects of this paper are concluded below.Design principles of embedded piezoelectric sensor dynamic weighing system is proposed in this paper. Using stone-based materials and the piezoelectric ceramic sheet to make separated stone based load cells, which are arranged in rows in asphalt pavement surface Integrally to weigh dynamically. It is no damage to the road and adapted widely in terms of vehicle dynamic weighing. By averaging the multiple sensor array can effectively reduce the error level of weighing system measurements.The finite element method is used to analyze the linearity of the weighing system and make the stress analysis sensors different response under different tire stress distribution. Monitoring regional peak stress and the correlation between stress response integral value and tire weight are studied. It shows that the typical tire stress distribution under stress response integral and makes a good correlation with tire weight. So the vehicle dynamic weighing sensitivity can be established based on stress response integration. It will have some impact on the measurement results when tire go through the sensor array at different locations, so the test should ensure that the length of the sensor array is long enough.Embedded piezoelectric sensor dynamic weighing system is arranged in pavements. Multiple times of weighing measurement are made to the same vehicle. Using the integral value of the stress response determined the sensitivity of dynamic weighing to study the influence of vehicle speed and long-term impact loads on weighing sensitivity. The study shows that when using integral value of the stress to determine the sensitivity of dynamic weighing, sensitivity discreteness is quite small, the sensitivity of dynamic weighing is not sensitive to vehicle speed, and weighing sensitivity changes significantly under long-term impact loads, which needs to be amended.