**3.3 Cable-stayed bridge**

A cable stayed bridge, **Figure 4**, consisting of cables connected to load-bearing tower pylons and the deck below are used to span large distances. By connecting the cables to the pylons a fan like pattern is created. In effect the cable-stayed bridge is a statically indeterminate continuous girder bridge where the dead and live load internal forces are smaller than a girder bridge. With their structural members in tension the cable-stayed bridge makes more efficient use of materials.

In a paper by J. Radic et al. [4] the authors point out a great number of parameters are required for the shaping of cable-stay bridges, where principal requirements for the shaping of beams, stay cables and pylons are explained. Cable-stayed bridge design analysis must take into account strong interactions between principal loadbearing structural elements. As an example the principal properties of the Jarun bridge cable-stayed bridge in Croatia are explained in the light of guidelines for the shaping of cable stay bridges, and an accent is placed on specific features of this bridge [4].

**Figure 3.** *Example of a steel beam bridge. CC BY-SA 3.0.*

#### **Figure 4.**

*Cable-stayed bridge Rio Antirrio Bridge in Greece. Opened 2004 length 2.8 km. CC BY-SA 3.0.*

## **3.4 Cantilever bridge**

The cantilever bridge, **Figure 5**, made from structural steel or pre-stressed concrete, using simple trusses and beams, connects two cantilever arms in a suspended span center piece with no direct support underneath. Horizontal beams and diagonal bracing support the bridge load with no vertical bracing. The first cantilever bridge in 1866 was the Hassfurt Bridge over the Main River in Germany, with a span of 124 feet, and was considered a major engineering breakthrough in bridge construction at the time. The Canadian bridge Pont de Quebec, Quebec City, **Figure 4**, which opened in 1919, after 30 years and two collapses, is the longest cantilever bridge in the world.

In a paper by Rajeshirke et al., India [5] the authors describe the use of balance cantilever bridges in India which are widely used in hilly regions where supporting from the bottom is difficult. The name Balance Cantilever Bridge is a construction methodology which balances out the cantilever portion and is one of the most effective methods of building bridges without the need of false work. Balanced cantilever bridges are used for special requirements like construction over traffic, short lead time compared to steel and use local labour and materials. Extradosed bridge is a unique type of bridge between Girder Bridge and cable-stayed bridge. As most of the literature covers either balance cantilever bridge or extradosed bridge, this paper introduces and attempts to summarize comparative study of balance cantilever and extra dose bridge with its span arrangement, span by depth ratio, and pre-stressing of steel [5].

### **3.5 Suspension bridge**

Developed in the early 1800s suspension bridges were a marvel in bridge engineering and capable of spanning great lengths. The basic components of a suspension bridge are main cables, towers, and secure anchorages at both ends of the bridge. The deck carrying the dead load and vehicle traffic is hung from the suspension cables with vertical suspenders. The load carrying members are the main cables as tension members made of high-strength steel and are efficient in carrying loads. With this suspension cable configuration the dead weight of the bridge can be reduced making longer spans possible. Early suspension bridges had problems with vibrations and wind loading before the dynamics of wind loading on bridsges was understood. John Roebling was the first engineer to build suspension bridges designed for wind loading

**Figure 5.** *Pont de Quebec Opened 1919 987 m. CC BY-SA 3.0.*

*Perspective Chapter: Bridge Deterioration and Failures DOI: http://dx.doi.org/10.5772/intechopen.109927*

**Figure 6.** *John R Roebling Suspension Bridge Cincinnati, OH Opened 1867. CC BY-SA 3.0.*

with the Roebling bridge in Cincinnati, Ohio, **Figure 6**, and the Brooklyn bridge in New York City.

In a paper by Arioglu [6] the author describes "suspension bridges as masterpieces of the engineering profession with conceptually clear cut 5-piece load-bearing systems which are highly hyperstatic and undergo large displacements under loads having nonlinear behavior and are sensitive to horizontal loads, such as wind loading. Suspension bridges are the most elegant, aesthetic and relatively economic structures of our civilization. Suspension bridge designs are based on mathematical models, using known patterns of physical behavior, but have many unknowns and uncertainties. This paper explores practical mathematical expressions obtained through regression analyses to predict key design parameters of long span suspension bridges such as main geometric dimensions, material quantities/qualities and dynamic properties for preliminary design calculations.

A large design parameter database matrix for 20 long span suspension bridges was collected to bring out heuristic approximations through regression analyses. These regression models are used to examine the design parameters of 1915 Çanakkale Bridge Project, which will break the longest span record with a main span length of 2023 m and the tallest tower record with 318 m (IP Point). It was observed that the dimensions, mass distributions and material qualities selected for the design of 1915 Çanakkale Bridge agree with the findings of this study." [6].

The key design parameters for regression models used by Arigulo on existing suspension bridges correlated well with the design parameters for the new 1915 Canakkale Bridge over the Dardanelles in Turkey. The bridge opened in March 2022 with a span of 3.7 km and is the longest suspension bridge in the world.
