scholarly journals Influence of end Contsrains on the Global Behaviour of a Box Girder

2016 ◽  
Vol 6 (1) ◽  
pp. 7-15
Author(s):  
Daniela Mihaela Boca ◽  
A. Faur ◽  
A. Boca
Keyword(s):  
Prestressed Concrete ◽  
Transport Infrastructure ◽  
Box Girders ◽  
3D Fem ◽  
Important Data ◽  
Box Girder ◽  
Fem Model ◽  
Global Behaviour ◽  
Applied Forces ◽  
Precast Prestressed Concrete

Abstract This study aims to presents the importance of end constrains, boundary conditions and position of the applied forces regarding the design of precast/prestressed concrete box girders. The study is based on a destructive test which was performed on a 37.1 m span single-cell prestressed concrete box girder. The scope of the test was to certify the usage of such girders for the new Transylvania motorway bridges. The test is numerically reproduced through a full 3D FEM model implemented in SAP2000. The influence of the end diaphragms is considered by analysing the beam’s behaviour to six loading conditions: one of which is replicating the loadings during the test, while the others are conceived as real vertical and horizontally loading scenarios. The results obtained for the girders with and without end constrains are compared. The performances of both design solutions in the presence of prestressing are highlighted where applicable. It is considered that the results of this study may provide very important data if considering that Romania has an urgent need to realize a modern and an adequate transport infrastructure.

scholarly journals Computation of Deflections for PC Box Girder Bridges with Corrugated Steel Webs considering the Effects of Shear Lag and Shear Deformation

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Wei Ji ◽  
Kui Luo ◽  
Jingwei Zhang
Keyword(s):  
Shear Deformation ◽  
Prestressed Concrete ◽  
Displacement Function ◽  
Shear Lag ◽  
Longitudinal Displacement ◽  
Box Girders ◽  
Element Analysis ◽  
Box Girder ◽  
Bridge Model ◽  
Bridge Models

Prestressed concrete (PC) girders with corrugated steel webs (CSWs) have received considerable attention in the past two decades due to their light self-weight and high prestressing efficiency. Most previous studies were focused on the static behavior of CSWs and simple beams with CSWs. The calculation of deflection is an important part in the static analysis of structures. However, very few studies have been conducted to investigate the deflection of full PC girders or bridges with CSWs and no simple formulas are available for estimating their deflection under static loads. In addition, experimental work on full-scale bridges or scale bridge models with CSWs is very limited. In this paper, a formula for calculating the deflection of PC box girders with CSWs is derived. The longitudinal displacement function of PC box girders with CSWs, which can consider the shear lag effect and shear deformation of CSWs, is first derived. Based on the longitudinal displacement function, the formula for predicting the deflection of PC box girders with CSWs is derived using the variational principle method. The accuracy of the derived formula is verified against experimental results from a scaled bridge model and the finite element analysis results. Parametric studies are also performed, and the influences of shear lag and shear deformation on the deflection of the box girder with CSWs are investigated by considering different width-to-span ratios and different girder heights. The present study provides an effective and efficient tool for determining the deflection of PC box girders with CSWs.

Design and Analysis of Anchorage Zone and Deviation Block of External Prestressed Concrete Bridge

2013 ◽  
Vol 710 ◽  
pp. 342-347
Author(s):  
Bing Yi ◽  
Fang Yuan Li
Keyword(s):  
Prestressed Concrete ◽  
Optimization Design ◽  
Finite Element Models ◽  
3D Fem ◽  
Box Girder ◽  
Continuous Rigid Frame Bridge ◽  
Rigid Frame ◽  
Key Points ◽  
Prestressed Concrete Bridge ◽  
Rigid Frame Bridge

As an external prestressed concrete box girder continuous rigid-frame bridge with the longest span in China, the Xiantan Bridge was reported in this paper for its special characteristics. The key points of the end cross beam for anchorage zone and deviation block for the deviator were introduced in detail for its design. The finite element models for them with 3D FEM were created to get the stress state to ensure the safety. Taking the stress distribution results into account, the optimization design for the thickness for these key locations was reported too. The results can provide reference for the similar projects.

Creep Effects on Simply Supported Prestressed Concrete Box Girder of High-Speed Railway with Ballastless Tracks

2012 ◽  
Vol 238 ◽  
pp. 733-737 ◽  
Author(s):  
Wang Fang ◽  
Bing Han ◽  
Shao Kun Yang
Keyword(s):  
Prestressed Concrete ◽  
High Speed ◽  
Element Model ◽  
Dead Load ◽  
Box Girders ◽  
Box Girder ◽  
High Speed Railway ◽  
Simply Supported ◽  
Creep Models ◽  
Curing Age

Creep will lead to increasing deflection of prestressed concrete girder, which may induce rails uneven, especially to ballastless tracks in high-speed railways. In this paper, two creep models, CEB-FIP90 and ACI209, were used in a finite element model to analyze influences of creep on simply supported prestressed concrete box girders which are used in high-speed railway in China. Sensitivity analysis was carried on towards curing age, secondary dead load, loading time and prestressing method on deformation of the girder. The results show creep should be controlled in engineering to ensure driving security.

Genetic Analysis and Repair of Cracks in Prestressed Concrete Box Girders during Precast Period

2011 ◽  
Vol 366 ◽  
pp. 55-58
Author(s):  
Shi Ming Liu ◽  
Shun Bo Zhao
Keyword(s):  
Genetic Analysis ◽  
Prestressed Concrete ◽  
Initial Period ◽  
Environmental Condition ◽  
Box Girders ◽  
Construction Procedure ◽  
Precast Prestressed Concrete ◽  
Space Width ◽  
Construction Works

During the initial period of precast prestressed concrete box girders in a bridge, some cracks appeared in five box girders. The paper describes the crack states including location, elongation, space, width and depth. The geneses of the cracks are analyzed considering the concrete proportion, environmental condition and construction procedure. Four of them were permitted to be used after mending of these cracks and another one was abandoned directly. After the preventing measurement was adopted, no cracks appeared in the follow-up precast box girders. The experience can be as reference for the similar construction works.

Transverse Design of Adjacent Precast Prestressed Concrete Box Girder Bridges

PCI Journal ◽  
1996 ◽  
Vol 41 (4) ◽  
pp. 96-113 ◽  
Author(s):  
Ahmed EI-Remaily ◽  
Maher K. Tadros ◽  
Takashi Yamane ◽  
Gary Krause
Keyword(s):  
Prestressed Concrete ◽  
Box Girder Bridges ◽  
Box Girder ◽  
Girder Bridges ◽  
Concrete Box Girder ◽  
Concrete Box Girder Bridges ◽  
Precast Prestressed Concrete

The Detection Research of Tension about Vertical Prestressed Fine Rolled Twisted Bar in Box-Girders Construction of Civil Engineering

2012 ◽  
Vol 568 ◽  
pp. 134-137
Author(s):  
Xing Yuan Lin ◽  
Yan Feng Wu ◽  
Wei Wei Wang ◽  
Feng Zhang
Keyword(s):  
Prestressed Concrete ◽  
Civil Engineering ◽  
Tensile Force ◽  
Construction Process ◽  
Box Girders ◽  
Box Girder ◽  
Box Beam ◽  
Rigid Frame ◽  
Relationship Of ◽  
The Relationship

At present, vertical prestress detection is almost blank during box-girders construction of civil engineering . In order to effectively detect the effective tension at box-girder construction process in civil engineering based on the theory of structural dynamics, scene detection means, the relationship of box-girder vertical prestressing tensile force and dynamic characteristics of the exsertion segment reinforced was established. Vertical prestress of part of the box beam segments of a three-span prestressed concrete continuous rigid frame was detected , the shortcomings of the current vertical prestressing tensile force was analyzed . The results show that: the proposed method is direct, effective and able to effectively monitor the vertical prestressing tensile force. The research has important theoretical and engineering applications for crack prevention of box-girders.

scholarly journals Structural Health Monitoring of Precast Concrete Box Girders Using Selected Vibration-Based Damage Detection Methods

2010 ◽  
Vol 2010 ◽  
pp. 1-21 ◽  
Author(s):  
Zhengjie Zhou ◽  
Leon D. Wegner ◽  
Bruce F. Sparling
Keyword(s):  
Damage Detection ◽  
Prestressed Concrete ◽  
Precast Concrete ◽  
Detection Methods ◽  
Box Girders ◽  
Localization Accuracy ◽  
Structural Health ◽  
Proportional Increase ◽  
Low Levels ◽  
Precast Prestressed Concrete

Precast, prestressed concrete box girders are commonly used as superstructure components for short and medium span bridges. Their configuration and typical side-by-side placement make large portions of these elements inaccessible for visual inspection or the application of nondestructive testing techniques. This paper demonstrates that vibration-based damage detection (VBDD) is an effective alternative for monitoring their structural health. A box girder removed from a dismantled bridge was used to evaluate the ability of five different VBDD algorithms to detect and localize low levels of spalling damage, with a focus on using a small number of sensors and only the fundamental mode of vibration. All methods were capable of detecting and localizing damage to a region within approximately 1.6 times the longitudinal spacing between as few as six uniformly distributed accelerometers. Strain gauges configured to measure curvature were also effective, but tended to be susceptible to large errors in near support damage cases. Finite element analyses demonstrated that increasing the number of sensor locations leads to a proportional increase in localization accuracy, while the use of additional modes provides little advantage and can sometimes lead to a deterioration in the performance of the VBDD techniques.

Research of Prestressed Concrete Hollow Multi-Ribbed Composite Box Girder

2011 ◽  
Vol 368-373 ◽  
pp. 705-709
Author(s):  
Ping Hu ◽  
Dong Qi Zhao ◽  
Hui Li ◽  
Gui Feng Song ◽  
Yi Jun Tang
Keyword(s):  
Prestressed Concrete ◽  
Structure Form ◽  
Box Girders ◽  
Two Phase ◽  
Box Girder ◽  
Force Structure ◽  
Assembly Structure ◽  
Continuous Girder Bridge ◽  
Girder Bridge ◽  
Beam Bridge

Base the shortcomings of pre-simple-supported post-continuous girder bridge construction, a new beam-bridge convert structure system is proposed, that is a kind of structure form of prestressed concrete hollow multi-ribbed composite box girders, the calculation method of two phase and noting are put forward. the kind of Cast-in-place assembly structure is light self-weight, force structure reasonable, easy construction, overall good and overall cost low.

scholarly journals Effect of Construction Method on Shear Lag in Prestressed Concrete Box Girders

2012 ◽  
Vol 2012 ◽  
pp. 1-17 ◽  
Author(s):  
Shi-Jun Zhou
Keyword(s):  
Cross Sections ◽  
Prestressed Concrete ◽  
Construction Process ◽  
Shear Lag ◽  
Box Girders ◽  
Box Girder ◽  
Construction Methods ◽  
Concrete Box Girder ◽  
Concrete Box Girder Bridges ◽  
Girder Bridge

Most of the previous researches conducted on shear lag of box girders were only concerned about simple types of structures, such as simply supported and cantilever beams. The structural systems concerned in these previous researches were considered as determined and unchangeable. In this paper, a finite element method considering shear lag and creep of concrete was presented to analyze the effect of dynamic construction process on shear lag in different types of concrete box-girder bridges. The shear lag effect of the three types of a two-span continuous concrete beam classified by construction methods was analyzed in detail according to construction process. Also, a three-span prestressed concrete box-girder bridge was analyzed according to the actual construction process. The shear lag coefficients and stresses on cross sections along the beam including shear lag were obtained. The different construction methods, the changes of structural system with the construction process, the changes of loading and boundary conditions with the construction process and time, the prestressing, and creep were all imitated in the calculations. From comparisons between the results for beams using different construction methods, useful conclusions were made.

Sign in / Sign up

Export Citation Format

Share Document