The use of composite structures in construction is increasing. The optimized combination of the two materials concrete and steel produces particularly cost-efficient structures. This book presents a ...large number of numerical examples with detailed explanations of the provisions of Eurocode 4. It deals with the most common structural components in building construction: beams, columns and slabs. Furthermore, comprehensive chapters provide insight into the topics of creep and shrinkage, as well as fatigue.
This book enables the reader to efficiently perform analyses of composite structures. It is a valuable reference book for professionals as well as an outstanding means for students to become familiar with the Eurocode 4.
The fatigue life assessment of orthotropic steel decks of highway bridges still hasn’t been sufficiently investigated. The inspection results of orthotropic steel decks have shown that their working ...life can be shorter than other members of steel highway bridges due to fatigue. This means that particular details of orthotropic decks can be critical regarding the service life of a bridge. The fatigue life of typical details of orthotropic steel decks for the real load models in Croatia and for the standardized load model of highway bridges in Eurocode has been analysed. The reliability indices have also been calculated for these details and they have been used to determine reliable fatigue life. The paper proposed the introduction of the reliable fatigue life concept which is not explicitly specified in the modern standards for structures. This concept has been offered as well as the guidelines for further probabilistic research on reliable fatigue life.
A review of current surveys related to composite columns made of concrete filled tubes with embedded steel cores, known as Geilinger columns, is presented in the paper. Advantages and scope of ...application of this innovative composite column type are presented. Calculation of such columns according to the general method given in EN 1994-1-1, which is applied with known geometrical and structural imperfections, is explained. The simplified calculation method suitable for engineering practice is also considered. The aspects of fire resistance design are discussed.
U radu je prikazan pregled suvremenih istraživanja spregnutih stupova izvedenih s cijevima ispunjenim betonom i s umetnutim čeličnim jezgrama, a poznatih su kao Geilinger stupovi. Prikazane su ...prednosti i područje primjene tih inovativnih tipova spregnutih stupova. Objašnjen je proračun ovakvih stupova prema općoj metodi danoj u EN 1994-1-1 koja se primjenjuje s poznatim geometrijskim i strukturnim nesavršenostima. Također je razmatrana pojednostavnjena metoda proračuna prikladna za inženjersku praksu. Obrazloženi su aspekti proračuna požarne otpornosti.
This chapter demonstrates the design of a composite column with partially concrete‐encased H‐section subject to axial compressive load and bending moment. In order to ensure adequate force transfer ...between the steel and the concrete, stud connectors and reinforcement are provided. The resistance of the cross‐section to combined compression and bending is calculated in two ways: using the interaction curve of N–M and using the interaction polygon of N–M. Also, the chapter illustrates the design of load introduction for combined compression and bending. The forces at the interface are determined by elastic theory and by plastic theory. However, the bending moment about the z‐z axis was caused by taking into account the equivalent member imperfection about the z‐z axis. This means that the check of resistance should be carried out for combined compression and biaxial bending. The check based on the interaction polygon was carried out in accordance with EN 1994‐1‐1.
Beam to Beam Joints Dujmović Darko; Lukačević Ivan; Androić Boris
Composite Structures According to Eurocode 4,
2015, 2014-12-08
Book Chapter
This chapter illustrates four types of secondary beam to primary beam pinned joints. In cases where speed of erection is an important consideration, the secondary to primary beam pinned joint can be ...used. In this case, the secondary beam is connected to the primary beam by means of the single extended end plate which is welded onto the cleat. The cleat is welded onto the top flange of the primary beam. The extended end plate is slotted and welded onto the cleat, so the transmission of tensile force from the secondary to the primary beam is ensured. Two variants of continuous beam to beam joints are shown in the chapter. Continuity is achieved by means of cover plates welded onto the top flanges of the secondary beams and contact plates. Alternatively, the continuity can also be ensured by steel reinforcement in the concrete slab.
Effective Width of Concrete Flange Dujmović Darko; Lukačević Ivan; Androić Boris
Composite Structures According to Eurocode 4,
2015, 2014-12-08
Book Chapter
This chapter illustrates the method of calculation of the effective width of the concrete flange due to shear lag. The method is recommended in clause 5.4.1.2, EN 1994‐1‐1. It is considered that a ...continuous composite beam consists of two spans and a cantilever. We need to calculate the value of the effective width of the concrete flange b
eff
for the mid‐span regions AB and CD, for the support regions BC and DE and for the support at A. Elastic global analysis may be based on the stiffness calculated using the results for AB and CD. However, the differences between these values are so small that the structural element ABCDE can be analysed as a beam of uniform section with the effective width of the concrete flange b
eff
= 1,650 m.
This chapter designs a two‐span composite beam according to the plastic–plastic procedure. In this case, action effects are calculated by rigid plastic global analysis, and the resistance to bending ...is based on a plastic model. For this procedure, all cross‐sections of the composite beam should be in class 1. The continuous beam has changed the static system from statically indeterminate to statically determinate. Rigid plastic global analysis can be used for ultimate limit state verifications other than fatigue. Also, this method is not applicable in cases where second‐order effects have to be considered. For calculation internal forces, bending moments and deformations at serviceability limit state, the elastic global analysis should be used. The restrictions on the application of rigid plastic global analysis given in clause 5.4.5, EN 1994‐1‐1, are such that linear ‐ elastic global analysis is often used for composite beams.
This chapter shows the calculation of the value of time‐dependent strains of concrete due to creep and shrinkage. These values influence the determination of the effects of actions. In the chapter, ...the effect of action is related to the calculation of the design bending moment at the internal support of the continuous composite beam. This moment is obtained by summing the bending moment due to the actions (permanent and variable) and the bending moment due to shrinkage. Primary and secondary effects due to creep and shrinkage of the concrete flange must be taken into account appropriately. For the continuous beam, the global analysis is performed with defined regions of cracking of concrete, clause 5.4.2.3(2), EN 1994‐1‐1. Shrinkage of the concrete flange causes sagging curvature and shortening of the composite beam.
This chapter demonstrates the design of a composite column subject to axial compression. The concrete‐filled column consists of a circular hollow section filled with concrete. In concrete‐filled ...hollow sections no longitudinal reinforcement is normally necessary. However, if the design for fire resistance is required, the longitudinal reinforcement can be used, clause 6.7.5.2 (1), EN 1994‐1‐1. Since the considered member is subjected only to end compression, clause 6.7.3.5(2) enables buckling curves to be used. It is important to note that imperfections are unavoidable and that they result in deviations from the behaviour of member subject to “perfectly centred load”. Imperfections may be divided into geometrical imperfections and structural imperfections. The influence of geometrical and structural imperfections can be allowed for by equivalent geometrical imperfections which are given in EN 1994‐1‐1, and depend on the buckling curve. The use of buckling curves is limited to axially loaded members.
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