Structural behavior of non-symmetrical steel cable-stayed bridges non-symmetrical cable-stayed bridges;parametric study;design parameters;steel bridge;design guidelines; Despite of the growing number of built examples, the analysis of non-symmetrical cable-stayed bridges has not received considerable attention from the researchers. In fact, the effects of the main design parameters in the structural behavior of these bridges are not addressed in detail in the literature. To fill this gap, this paper studies the structural response of a number of non-symmetrical cable-stayed bridges. With this aim, a parametric analysis is performed to evaluate the effect of each of the main design parameters (the ratio between the main and the back span length, the pylon, the deck and backstay stiffnesses, the pylon inclination, and the stay configuration) of this kind of bridges. Furthermore, the role of the geometrical nonlinearity and the steel consumption in stays are evaluated.

Modern computational resources provide important and efficient tools for analyzing structures of all scales, materials, and typologies, especially historic structures. However, not all methods can correctly answer questions about the structural behavior of inherently discontinuous unreinforced masonry constructions. Such continuous methods, photoelasticity and finite element methods, are pervasively and incorrectly used to analyze masonry structures despite the availability of more appropriate methods. This article addresses the use of these different analyses by comparing the different results of two previous continuous model studies of the pier buttresses of Amiens Cathedral to new results using two discontinuous methods, discrete element methods, and graphical thrust line analysis. This case study validates the use of graphical thrust line analysis and challenges the use of continuous models in analyzing historic masonry constructions. Furthermore, these results resolve a longstanding debate about the placement of pinnacles while providing evidence that the analysis method must reflect physical behavior.

In a “classical” vertical planar arch bridge subjected only to in-plane loads, its funicular geometry (which is the geometry that results in an equilibrium state free from bending stresses, i.e., simply under axial forces) is contained within a vertical plane. In the so-called “spatial arch bridges,” their structural behavior extends from the essentially vertical in-plane behavior of the “classical” arch bridges to a three-dimensional behavior. The paper presents how the Force Density Method, which is a form-finding method originally developed for cable meshes, can be simplified to easily obtain three-dimensional funicular arches. The formulation and flow chart of the method is presented and discussed in detail within this paper. Additionally, some case studies illustrate its scope. This paper intends to be useful at the conceptual stage of bridge design when the three-dimensional geometry for the spatial arch bridge typology is considered either because of functional requirements, structural efficiency, or for aesthetical purposes.

The current paper relates the state of the art of construction of viaducts with a movable scaffolding system (MSS). Two different procedures are introduced: the traditional sequence and the new sequence applied to some viaducts in Spain. The traditional sequence consists of two phases: first, concreting the bottom slab and webs, and then concreting the top slab of the deck. Once the first and second casting phases are completed, the total prestressing force is introduced. The new sequence consists of concreting a self-supporting core (i.e., the bottom slab, webs, and only a portion of the top slab). Once the self-supporting core has hardened, a partial prestressing force is introduced so that the scaffolding can be advanced to the next span; the central zone of the top slab is cast in a second phase. Both sequences are described here with their constructive peculiarities and issues.