| With the in-depth implementation of the western development in China, and carrying on the strategy of enriching the province of Yunnan, more highways and municipal roads have been builded to meet the fast-growing economy. Non-abutment slant-legged rigid frame bridge, as a type of highway overcrossing or river-crossing bridge with a single span has an unique advantage of balancing horizontal thrust. The purpose of this paper is to study the non-abutment slant-legged rigid frame bridge. The content of this paper is divided into several aspects as follows:(1) this paper compared the slant legged rigid frame bridge and non-abutment slant-legged rigid frame bridge in economy. And also introduced several calculation methods of lateral bearing capacity of pile, especially the M-method. The economies of using the diagonal brace before and after are stated in this paper. Taking some bridge across Panlong river as a case study, the author found that when the materials of bearing platform was not unchanged, this bridge had a huge economic advantage that the materials of pile are saved25%.(2) this paper takes the bridge across Panlong river on south Agricultural Road in Kunming as an original model, and optimizes its design by Midas civil2010.The results of analysis of internal force and displacement show that the optimal span ratio of L1:L2is0.4to0.6:1, and that the optimal edge diagonal angle is from35°to55°.This paper also analyzed the effects of temperature on non-abutment slant-legged rigid frame bridge. By analyzing the cases, the author obtained a magnitude chart of comparing temperature stress with gravity stress in the condition of two kinds of thermal action.(3) This article do theoretical deduction on the oblique non-abutment slant-legged rigid frame bridge rotating and anti rotating mechanism in the plane. Because of the slant leg and side oblique rod, the skew slant leg rigid frame bridge without abutment effectively limits its plane rotation, and we verified it by numerical examples.The conclusions of this paper not only enrich theories about the non-abutment slant-legged rigid frame bridge, but also provide a preliminary basis for the designing and consultation of that style. |
