Study On The New T-beam Cross-sectional Design

To meet the increasing demand of traffic volumn and enhance the connectionbetween cities, much work has been done in the design and construction of highway inrecent years, among which bridge engineering in mountain areas makes up a largeportion．Simply supported T beam bridge（or simply supported continuous structure Tbeam bridge）is a structure form typical bridges in mountainous area and Taking theT-beam general diagram of the Department of Transportaion in2008asreference．After researching and Summing up this kind of bridge’s advantages anddisadvantages, The new T-beam cross-sectional(double T type) is putted forward．ThisT-beam has certain reference significance and selection of value onsubsequentmountain highway’s design and construction．This paper collects aesign and construction data of the T-beam with five pieces ofbeams from the available general diagram． Considering engineering quantity, hoistingweight, stability which the prefabricated beam builds in and the number of cast in situconcrete wet joint,this paper designs the new types of cross-section structure such assix pieces of double beams and four pieces of beams． Then a comparative analysis ofrigid connected beam method and grillage method is carried out to reach reasonablecalculation pattern for the load transverse distribution coefficient of T-beam bridge．By establishing finite element modle and using grillage method, the loadtransverse distribution coefficient of T-beam with the span being20m,30m, and40min the form of4,5and6pieces of beams is worked out． In condition of optimalreinforcement ratio, a comparative analysis of the internal forces during constructionunder transient situation, the internal forces in carrying capacity limit state underpersistant situation, and the limit state and internal forces for normal use underpersistant situation of the T-beam bridge with the same span but different types ofcross-section is carried out to obtain a reasonable design of T-beam bridge of mountainhighway． Considering the hoisting quantities for T-beam with different span anddifferent cross-section styles during construction, the T-beam with the optimalcross-section style is selected from the perspective of construction, which provides abasis for the the design and construction of the bridge with the same structure type inthe future．...