China
Africa
Explore chapters and articles related to this topic
Concrete Arch Bridges
Published in Hulya Sonmez Schaap, Köpriyet: Republican Heritage Bridges of Turkey, 2023
Construction and Special Applications: The construction of an arch bridge is one of the most challenging stages, even dominating the design since the arch is only stable once it reaches its finished state. During the entire construction process, it has to be fully supported on temporary structures. Various support methods are adopted during their construction. The simplest and most economical form was the wooden centring combined with formwork for concreting. Centring is a temporary structure built to provide the support and necessary shape for an arch during its construction. For longer spans, centring was supported as cantilevers from towers erected on piers and from the banksides. Nearly all bridges of the early Republic era were constructed with wooden centring, except the Malabadi bridge which used an arch made of steel as scaffolding after the previous centring was washed away by a sudden flood during construction.
Static behaviour of in scale masonry vaults under imposed settlement of the supports
Published in Renato Lancellotta, Carlo Viggiani, Alessandro Flora, Filomena de Silva, Lucia Mele, Geotechnical Engineering for the Preservation of Monuments and Historic Sites III, 2022
F. Roselli, M. Alforno, F. Venuti, A.M. Bertetto
The experimental set up of the barrel vault was designed to allow both opening and shear tests to be performed (Figure 2). Specifically, one of the abutments is fixed in the x direction and allowed to move in y direction (simple shear mechanism), while the other abutment is fixed in the y direction and can be moved in x direction (opening mechanism). Four pins support the centring, and the slab where they are fixed can be lowered to allow the centring removal after completion of the vault.
Construction materials and main structural elements
Published in Pere Roca, Paulo B. Lourenço, Angelo Gaetani, Historic Construction and Conservation, 2019
Pere Roca, Paulo B. Lourenço, Angelo Gaetani
Centring is a temporary timberwork used by stonemasons to achieve the correct geometry of vaulted system and roof spires (Figure 3.43). The timber structure was also needed as scaffolding (i.e. temporary support).
Construction Process of Vaults in Masonry Bridges: The Importance of Centrings
Published in International Journal of Architectural Heritage, 2022
Benedetta Orfeo, Leonardo Todisco, Javier León
“The arch never sleeps” asserts an ancient Arabian proverb concerning the permanent compressive stresses among its elements to keep equilibrium (Huerta Fernández 1996). This statement is true only when the keystone is placed and the arch (vault) is completed. Until that moment, the voussoirs need to be supported to achieve the final desired shape. This role of support, as already stated, is played by the centring, which is the auxiliary provisional scaffolding composed of a finite number of frames, which in turns are characterised by timber elements (Figure 4a shows a front view of the structure, focusing on one of the three frames; Figure 4b illustrates a perspective view of the whole structure). The centring role is not only to carry the load of the voussoirs during the construction process, but also to define the shape of the vault representing a geometrical guide for the positioning of every single arch voussoir (Durán Fuentes 2007).