Study On The Typical Structure Of Low Grade Rural In Tibet

Along with the continuous improvement and optimization of highway network,China's growing emphasis on low grade highway construction,municipalities and also started to establish suitable local low-grade pavement typical structure of roads,but there are some problems.Current road design specifications were directed at secondary and secondary Highway pavement structure design,low-volume pavement structural design methods have no clear guidance,and each area there is a big difference,also makes it difficult for standard uniform.After exploring in pavement structure and construction technology of some local highways because lack of construction technology,construction personnel quality is not up to the requirements,many appeared in the early period of the rural road structure destruction and iMPairment,plus maintenance less or when the wrong way,seriously affecting the road using performance and structural performance,reduce the service life and increased construction costs.Because of Tibet's unique geographical location,special climate,coMPared to other provinces and cities,is characterized by high-elevation alpine areas and ultraviolet rays are very strong.May exist on the iMPact of road construction on the former is permafrost,causing surface freeze-thaw,surface cracks,which effects of ultraviolet radiation on asphalt pavement and the effect of temperature on asphalt pavement line or even close.Traffic conditions and geological specificity,simple structure typical of lower grade roads in rural areas of Tibet must be studied in depth.Paper specific research content following:The study on two main typical structure of rural highway in Tibet are the bituminous pavement,the cement concrete pavement.Based on the analysis of rural highway pavement structure soil base and traffic and combining with the surface of Tibet forward basic conditions of use,the paper recommend the range of the range of the surface and the basecourse materials of design parameters.Finally taking the accumulated equivalent axle,modulus of soil subgrade resiliency,climatic regionalization as variable,the paper put forword the rural highways typical structure of bituminous pavement,cement concrete pavement in rural road in Tibet.