Papers by Keyword: Effective Flange Width

Abstract: There are few studies about the shear lag effect and the effective flange width of the PC (Prestressed Concrete) box girder bridge with corrugated steel webs throughout the world in current time. In the present paper, based on the three-dimensional finite element analysis for a long-span continuous PC box girder bridge with corrugated steel webs and the corresponding conventional box girder bridge with concrete webs, a comparative study on the shear lag effect under vertical loads are carryied out together with the analyslis on the coefficient of the effective flange width. The results show that in the PC box girder with corrugated steel webs, the transverse distributions of longitudinal normal stress on the section of the slabs are obviousely non-uniform and they are different with those in the conventional PC box girder with concrete webs. And moreover, the shear lag effects in top slab of the PC box girder with corrugated steel webs are almost less obvious than those of the conventional PC box girder with concrete webs. However, the shear lag effects in bottom slab of the PC box girder with corrugated steel webs are almost similar to those of the conventional PC box girder with concrete webs, no matter what kind of vertical bending moment the cross section is subjected to

Abstract: In the present paper, based on the three-dimensional finite element analysis for a three-span continuous PC box girder bridge with corrugated steel webs and the corresponding conventional box girder bridge with concrete webs, a comparative study on the shear lag effect under self-weight is carryied out together with the analyslis on the coefficient of the effective flange width. The results show that At the sections in the negative bending moment near the intermediate piers, the shear lag effect in the bridge with corrugated steel webs is more obvious than that in the bridge with concrete webs by 8%; and the corresponding effective flange width coefficient in the bridge with corrugated steel webs is even smaller than 0.9, so the shear lag effect at these sections should be considered in the design of this type of bridges. At the mid-span section of the middle span of a three-span continuous bridge either with corrugated steel webs or concrete webs, the shear lag effect can be omitted since the corresponding effective flange width coefficient there is close to 1.0.

Abstract: To consider the contribution of the floor to the flexural capacity of frame beams, slabs are usually equivalent to floor "effective flange width" . However, there are no academia acknowledged conclusions about the value of effective flange width was drawn. This article introduced the theories about the calculation of "effective flange width" and studied the influence of node type to the value by comparing various MIDAS simulation models. Finally, we concluded suggested formulas after combining the analysis and experimental results.

Abstract: Effective flange width’s value of U-section steel-encased concrete composite beam was studied by ANSYS. Based on the static equivalent principle, the general rules of effective flange width changed with load are summarized by finite element analysis and considering the effect of 4 factors: width-span ratio, loading form, concrete thickness, and material strength including concrete strength and steel strength. The analysis results show that wide-span ratio and load form has a greater impact on the effective flange width; concrete thickness and material strength’s effects can be negligible.

Abstract: “strong beam and weak column”is the main failure states of reinforced concrete frame structure in the earthquake．This paper studies the influence on the virtual cross-section bearing capacity on extremity of frame beam in reinforced concrete in experiment through the project example and analysis of finite element method,such as slab’s reinforcement，the rigidity of frame beam, the rigidity of orthogonal beam and so on．Exploring the mechanism of slab and frame work together to determine the width of effective flange，which provides references for structural design and engineering application．

Abstract: “strong beam and weak column”is the main failure states of reinforced concrete frame structure in the earthquake．This paper is the experimental study of the influence on the virtual cross-section bearing capacity on extremity of frame beam in reinforced concrete，which is affected by some element，such as slab reinforcement，the rigidity of orthogonal beam and so on．Exploring the mechanism of slab and frame work together to determine the width of effective flange，which provides references for structural design and engineering application．

Abstract: The paper designed three joints namely beam-column joint of reinforced concrete frame without slab and two beam-column joints of reinforced concrete frame with slab, using different loading methods (one direction and two directions) to experiment. The paper studied failure behavior, load-carrying capacity, and slab participation in flexural behavior of beam under different loading modes. Experiment shows that for the joints with slab, flexural capacity at end of the beam under two direction loads than one direction loads lows by about 10%; under one direction load, effective flange width of slab should be taken 8 times thickness, under two direction loads, effective flange width of slab should be taken 10 times thickness.

Abstract: The study of girder-to-column joints under experiment and numerical analysis was carried out to evaluate change of the flexural capacity of the joints with the 2-layer upper reinforcement of girder within rectangular section and the single-layered upper reinforcement at the girder flange. The distribution of the upper reinforcement of girder within the effective flange width was the variable in the experiment and numerical study. The ultimate strength of the specimen with 2-layer upper reinforcements of girder was larger than that of the single-layered specimen by maximum 17.4%. Based on the results of this experimental study, for the single-layered tension reinforcement it is recommended to provide 15% additional reinforcement at twice slab thickness on each side of the main girder to attain the flexural capacity equal to the 2-layered case.