Study On Reasonable Structure Design Of Flexible Base Asphalt Pavement

Due to special climate conditions of seasonal frozen area, coupled with the growing automotive overload, in the early delivery semi-rigid base asphalt pavement which is built in seasonal frozen area appeared a series of more or less damage such as rutting, cracking, water damage, etc.. In recent years, shrinkage characteristics that are taken account into in the semi-rigid base asphalt pavement inherent defects lead to reflective cracking and mud pump which grassroots phenomenon appears under the combined action of water,temperature and load. To address the reflective cracking from the pavement structure, by drawing on foreign flexible Base Asphalt Pavement mature application technology it has a very important practical significance to carry out flexible base asphalt pavement in the application and research of seasonal frozen region.This article studies in the seasonal frozen region reasonable highway structure and flexible asphalt pavement performance, analyzes the course of their environment ‘s interaction about seasonal frozen area of asphalt pavement and discusses damage forms of asphalt pavement in the seasonal frozen region. Through the survey of semi-rigid asphalt pavement and usage of flexible asphalt pavement, clear pavement structure advantages and disadvantages and propose reasonable structure combination suitable for seasonal frozen area of Flexible Base Asphalt Pavement on this basis. Let surface deflection, tensile strain of asphalt layer bottom, semi-rigid bottom layer tensile stress, stress ratio of graded gravel layer, and compressive strain on top of subgrade as the control targets, considering the different state of contact between each structural layer and different load conditions, use ANSYS finite element program, a reasonable thickness of material asphalt pavement structural layers and various factors are studied systematic analysis of flexible base under recommended for seasonal frozen area of the climate and traffic load asphalt Pavement.In order to verify and promote the laboratory study, in Tong-dan highway of Jilin Province, pave a total of four test road Flexible Base, where there are two Flexible Base Asphalt Pavement structures and two modular base asphalt pavement structures. This will not only test the performance of flexible asphalt pavement,but also provide reliable theory foundation and practice experience to fully promote and apply wise flexible base asphalt pavement’s structures.