A Research On The Shear Lag Effect Of Long Span Curve Continuous Rigid Frame With High Pier

In recent years, with the development of our country super highway, particularly, the large-scale construction of mountain expressway, the curve beam bridge becomes a kind of important bridge type in the modern transportation engineering and has gotten an extensive application. The curve beam bridge can nicely adapt the restriction of geography, consumedly reduce the extension of line and construction cost. However, because of lacking norm, it usually causes the engineers neglect of the influence of the shear lag effect .The shear lag effect makes the box girders of curve continuous rigid-frame bridges appear transverse crack.Above all, the paper introduces the definition of the shear lag effect and current research circumstance. Then, based on the Bai Jianhe Bridge, by using the space solid finite method, the paper gets the shear lag coefficients, of different points of cross sections that belong to curved box girders, under dead load and prestressing force in completed construction. The paper studies the influence effect of the curve bridges with different ratio of beam depth and different height of piers.The main conclusions are as follows:1. The shear lag effect of different points which belongs to same cross sections, aroused by dead load and prestressing force, is different. And the difference grows with the ratio of beam depth reducing.2. To the curve continuous rigid-frame bridges with the radius less than 800 meter, the shear lag effect which is aroused by dead load, the influence of the radius can't be ignored. If the shear lag effect is aroused by prestressing force, the influence of the radius can be ignored.3. The shear lag coefficient can be changed by different height of pier, but the influence is not lager at all.This paper can make people understand the shear lag of effect curved continuous rigid-frame bridges distinctly, and would provide references for engineering designing in curved beam bridges.