Considering Reasonable Design Of The Long-span Concrete Continuous Rigid Frame Bridge Side Span Ratio Of Creep

Whether the edge selection of span ratio is reasonable, not only affect the rationality ofthe dead load internal force distribution, affects the rationality of the design of prestressedand economy, affect the construction difficulty, and so on, but also can produce very bigeffect to the total cost of the bridge, so choose the reasonable side span ratio should considerthe contents of the continuous rigid frame bridge in the overall design.Due to the size of the side span ratio will affect the arrangement of the prestressed,which in turn affect the structural internal force distribution and the size of the variable creep,and creep will affect the structural internal force redistribution, and the important influenceacross the middle and lower scratching and cracking. Therefore, we must consider theinfluence of creep in the reasonable boundary ratio. In the present it can’t accurate analysisand calculation under the condition of creep, creep as a random variable to envelope design,then, estimate their impact on the bridge. Hai xin sha bridge and Fu zhou bridge as theengineering background, the creep of envelope design method is used to analysis andresearch of large span continuous rigid frame bridge three spans and four spans reasonableside span ratio. through analysis and research on the optimal structure and can reduce theadverse effects of creep of structure reasonable span ratio in the side.the main work In this paper includes：(1) Reasonable concrete continuous rigid frame Bridges at home and abroad in recentyears are summarized in the side span ratio and creep of the relevant literature, this paperexpounds the reasonable considering the creep of side span ratio in the research presentsituation, points out the limitations of the present situation of research. And creep is putforward with the team as a random variable envelope design method.(2) Put forward the reasonable internal force of long span continuous rigid frame targetstate, emphatically discusses the reasonable side span ratio in the goal is to make continuousrigid frame bridge with reasonable internal force, simple construction, economic andreasonable, and the minimum bending energy method for cast-in-situ three and four spansection continuous beam in the reasonable span ratio in the study. (3) This paper introduces the mechanism of concrete creep, calculation theory andprediction model, and discusses the forecasting model of difference, and expounds theinfluence of continuous rigid frame bridge.(4) This paper Take the Hai xin sha bridge as the engineering background, studies thethree spans of the concrete continuous rigid frame bridge of reasonable span ratio byconsidering the creep.(5) This paper Take the Hai xin sha bridge as the engineering background, studies thethree spans of the concrete continuous rigid frame bridge of reasonable span ratio byconsidering the creep.The main conclusions In this paper includes：(1) Only at the the reasonable span ratio, the structure of the dead load distribution isreasonable, the prestressed beam layout is relatively easy, make the effect of creep on thestructural minimum at the same time.(2) Cast-in-situ three span section continuous beam of the reasonable span ratio is0.79.Cast-in-situ four span section continuous beam of the reasonable span ratio is0.81.(3) This paper Take the Hai xin sha bridge as the engineering background, byconsidering the creep, the three spans of the concrete continuous rigid frame bridge ofreasonable span ratio is0.552～0.576(4) This paper Take the Fu zhou bridge as the engineering background, by consideringthe creep, the three spans of the concrete continuous rigid frame bridge of reasonable spanratio is0.577～0.6.