A Study On The Estimation Of Road Surface Roughness Condition With Smartphone

Pavement roughness is an important index of grade evaluation,construction and acceptance of pavement,which directly reflects the comfort,safety and the use state of road surface,meanwhile it also provides an important reference for the repair,and maintenance of pavement.In the face of the increasingly heavy road maintenance tasks and the demand for the development of information management,how to quickly and conveniently carry out the detection of pavement roughness has been being a meaningful and practical topic.Fortunately,the popularity of smart phones and the development of the built-in sensor technologies provide road managers with a new type of convenient data collection of pavement roughnes—a fast collection of road surface conditions based on smart phones.This method has the advantages of convenient operation,low cost,accurate accuracy,etc.It plays an indispensable role in the development of road maintenance management informatization.First of all,the definition of pavement roughness is summarized,and the principles and characteristics of various traditional methods for measuring pavement roughness are analyzed and compared.Based on the above theoretical basis,the feasibility of smart phone sensor technology applied to pavement roughness measurement is analyzed.Then the common evaluation indicators and conversion relations of pavement roughness are introduced,and the International Roughness Index(IRI)is chosen as the evaluation index of the data collected by smart phones.Secondly,this paper extracts the pavement roughness index based on the acceleration data of smartphones.First,the Kalman filter is used to filter the acceleration and position information data obtained from the smartphone built-in sensors,from which the acceleration data that can truly reflect the vibration of the vehicle and the position information that matches the map are obtained.Based on the vehicle vibration model,the functional relationship between acceleration and road surface spectral density is established.Then,based on the conversion relationship between pavement power spectral density and international roughness index,the correlativity between vehicle acceleration data collected by smartphone application and IRI is established,and the evaluation result of road surface roughness based on acceleration is obtained.Seceral different grades of roads in Yangzhou are selected as the test sections.Collecting acceleration data with the smartphone application and calculating the pavement roughness index.Simultaneously,an inertial profiler is used to estimate pavement profile,and the average IRI of the test roads are calculate.By coparing and analyzing the experiment results,the feasibility and reliability of evaluating the roughness by smartphones are verified.Finally,this paper analyzes the impact of different vehicle models and vehicle speeds on the evaluation of road roughness using acceleration data collected by the smartphone application.Combined with the simulation and experiment results,the fitting relationship between the acceleration response and the vehicle speed at a given road section is obtained..