Criteria and influencing parameters for the design of piers of semi‐integral bridges

In statically indeterminate systems, imposed deformation generally cannot set freely. In order to achieve the deformation compatibility, constraint forces are required. From this, it can be deduced that the constraint forces for a given deformation are dependent on the stiffness of the system. The greater the stiffness, the greater the internal constraint forces. For this reason, constraint forces in reinforced concrete structures are generally worth mentioning and must be taken into account in the design. The accurate development of a constraint force depends on numerous factors. These are mainly the stiffness distribution over the length, stiffness of the cross section, ductility of the reinforcement and creep ability of concrete. To gain more information about the real behavior, experiments were carried out on reinforced concrete beams and prestressed beams.

Section: Code Regulationsmentioning

confidence: 99%

Constraint forces from imposed deformations

Berger

Feix

2018

“…Excessive creep and shrinkage can lead to extensive cracking, large deformations and, in the case of integral construction method, 1 to high constraint forces. 2 The rheological models for predicting creep and shrinkage of concrete were derived on the basis of a large experimental database. Hereby, relatively small specimens were investigated under constant laboratory conditions.…”

Section: Introductionmentioning

confidence: 99%

“…A realistic estimation of the time‐dependent concrete deformations is essential for an economic and durable design. Excessive creep and shrinkage can lead to extensive cracking, large deformations and, in the case of integral construction method, 1 to high constraint forces 2 …”

Section: Introductionmentioning

confidence: 99%

A 576 m long creep and shrinkage specimen – Long‐term deformation of a semi‐integral concrete bridge with a massive solid cross‐section

Herbers

Wenner²,

Marx

2022

Self Cite

For creep and shrinkage investigations, relatively small cylindrical specimens are generally exposed to constant climatic conditions. The derived mainly empirical prediction models are used for the calculation of large engineering structures with massive cross‐sections. In this paper, the expected values of the material models according to fib Model Code 2010 and Eurocode 2 are compared with monitoring data, which were acquired over a period of more than 12 years during a structural health monitoring of a large viaduct. It was found that in addition to the measured continuous increase in the viscous deformations, seasonal fluctuations due to climatic influences could also be detected. The numerical calculations show that the material models differ significantly in their magnitude and time course of the predicted viscous concrete deformations. In comparison with the monitoring data, a good agreement was achieved when using the material models according to Eurocode 2. The models of the fib Model Code 2010, on the other hand, underestimated the deformations of the massive bridge girder.

“…The response of structural components can be linear or nonlinear depending upon the amount of applied load. The response of soil generally is nonlinear 11–13 . This complication in SSI generates a challenging issue for the optimum design of the pile foundation in a FIB.…”

Section: Introductionmentioning

confidence: 99%

Temperature‐driven fatigue life of reinforced concrete integral bridge pile considering nonlinear soil–structure interaction

Verma

Mishra

2020

In this study, a five‐span fully integral reinforced concrete (RC) bridge has been investigated for fatigue life assessment of its RC piles considering the effects of environmental temperature variation and nonlinear soil characteristics. The effect of daily temperature variation on the abutment wall and pile foundation has been estimated. Multilayers of soil along the abutment pile depth have been considered in the formulations. The soil has been represented as 3D nonlinear springs. A new fatigue model has been used for crack initiation and propagation in the RC piles. In this model, a crack has been assumed to progress successively in three stages from the tension side of the pile. Finite element (FE)‐based modeling and analyses have been carried out to determine the longitudinal displacements and bending moment in piles, abutments, and piers. Furthermore, taking the bending moment as input crack mouth opening distance, crack propagation and fatigue life of pile have been assessed using the FE method‐based software. It is seen that the abutment piles suffer fatigue damage earlier as compared to the pier‐piles as a result of thermal and vehicular loads effects. Also, thermal fluctuation has shown little or no fluctuations in the longitudinal displacements of abutment and piles in the multispan fully integral bridge (FIB). It is expected that the proposed method will be helpful for the bridge engineers in designing the pile foundation passing through multiple soil layers against fatigue damage of a FIB in particular subjected to thermal and vehicular loading.