Research On Hydrodynamic Pressure In Asphalt Pavement Based On A Five-dimensional Optical Fiber Sensors

When cars were drove on the road covered with water, the relatively static water in the pressing action created a dynamic, instantaneous hydrodynamic pressure.Because of the vehicle in the process of forward movement, the water film between the tire and road surface continues to be squeezed and excludes it from both sides of the tire and tire tread gap. Under the effect of vehicle repeated loads, the water pressure repeatedly washed asphalt mixtures, then, the damage caused by the water aggravated. Water damages will not only reduce the roads service level, greatly shorten its life, but also bring huge economic losses. Therefore, research and analysis of hydrodynamic pressure on asphalt pavement has important practical significances.Currently, there are two main methods to test road hydrodynamic pressure, that is numerical analysis and field measurement. However, the numerical analysis is restricted by many factors when we try to get the data, meanwhile, it still needs to be tested, therefore, field measurement is still a common way to test the road hydrodynamic pressure.According the current achievements in the research at home and abroad. This paper put forward a five FBG sensors for hydrodynamic pressure measurement in the asphalt. The sensor is based on the basic principles of FBG,and it is made up of the five-way sensor.In this paper, The hydrodynamic pressure within asphalt pavement structure were measured at different speeds by this new sensor. Test results showed that: the hydrodynamic pressure works for a short time; the hydrodynamic pressure trends to be positive and negative alternately when the car is passing. In the same time, hydrodynamic pressure increases with the vehicle speed. Moreover, when the vehicle speed is consistently increased, the hydrodynamic pressure is not the same in different directions.The effect of dynamic water pressure makes the asphalt mixture working in a worse environment. Based on the data measured on field, this paper tries to develop a method to evaluate the performence of anti-spalling or anti-water damage in asphalt mixture in harsh environments. It was preliminarily found that the method can evaluate the ability of anti-flaking asphalt mixture. Further researces need to be completed in future.