Journal of South China University of Technology(Natural Science Edition) ›› 2024, Vol. 52 ›› Issue (8): 89-102.doi: 10.12141/j.issn.1000-565X.230566

• Architecture & Civil Engineering • Previous Articles     Next Articles

Mechanism and Mechanical Characteristics of Cable-Catenary Arch Combined Structure

HAO Tianzhi1,2(), LI Chunhua1, YANG Tao1(), LONG Xiayi2, DENG Nianchun1   

  1. 1.School of Civil Engineering and Architecture,Guangxi University,Nanning 530004,Guangxi,China
    2.Guangxi Beitou Transportation Maintenance Technology Group Co. ,Ltd. ,Nanning 530022,Guangxi,China
  • Received:2023-09-11 Online:2024-08-25 Published:2024-03-14
  • Contact: 杨涛(1979 —),男,博士,副教授,主要从事组合结构受力性能研究。 E-mail:yangt@gxu.edu.cn
  • About author:郝天之(1980 —),男,博士,正高级工程师、研究员,主要从事桥梁检(监)测、评估及维修加固研究。E-mail: htz0537@163.com
  • Supported by:
    the Science & Technology Base and Talent Project of Guangxi(AD23026026);the Natural Science Foundation of Guangxi(2023GXNSFAA026427)

Abstract:

With the increase of traffic volume and overloading of vehicles, the mechanical properties of early arch bridges under live load can no longer satisfy the needs of modern traffic due to low design load grade, lack of effective maintenance and long term operation. To improve the mechanical performance of this kind of arch bridges, this paper proposed a cable-catenary arch combined structure. The cables were symmetrically arranged on both sides of the arch rib to form a new force system, which could change the force transmission path of the catenary arch structure and reduce the internal force of the arch structure. Under the mechanical diagram of cable-arch combined structure, the force equation of the cable-arch combined structure was established based on the elastic center method, and the analytical solution of the internal force of the arch rib was deduced by the approximate curve integration method under the vertical moving load. The reliability of the analytical solution was verified by ANSYS finite element analysis software, and the influences of design parameters such as cable constraint position, arch-axis coefficient, rise-span ratio, and axial stiffness ratio on the internal force of the arch structure under lane loading were analyzed. The mechanical properties and internal variation rules of the cable-arch combined structure were revealed. The results show that the relative error between the analytical solution of the internal force and the finite element result is within 1%. The setting of the cable changes the positive and negative interval distribution of the bending moment influence line value of the arch structure, and effectively reduces the peak value of the bending moment influence line of the arch structure, which can greatly reduce the overall bending moment of the arch structure and make the bending moment distribution more uniform. From the arch foot to the arch crown, the reduction of the bending moment and the growth of the axial force of the arch structure gradually decrease. As the axial stiffness ratio increases from 0.02 to 0.10, the negative bending moment of the arch foot decreases nonlinearly, with the maximum decrease of 63.7%; the increase of the cable force is inversely proportional to its value, and when the cables are set at 0.3L (L is the span of the arch) from the arch crown, the cable force can be increased to 1.9 times that at the axial stiffness ratio of 0.02. The influence of the rise-span ratio on the internal force of the arch structure cannot be ignored. The greater the rise-span ratio is, the greater the change in internal force of the arch structure is. The effect of arch-axis coefficient on the internal force of the arch structure can be neglected.

Key words: cable-arch combined action, arch bridge reinforcement, catenary arch, rise-span ratio, arch-axis coefficient, internal force influence line, analytical solution

CLC Number: