Research on Deflection and Cracking of Prestressed Concrete Continuous Girder Bridge

2013 ◽  
Vol 838-841 ◽  
pp. 1014-1017
Author(s):  
Fan Guo ◽  
Yong Qing Yang ◽  
Sheng Qian Huang
Keyword(s):  
Prestressed Concrete ◽  
Parameters Optimization ◽  
Design Parameters ◽  
Box Girders ◽  
Prestress Loss ◽  
Box Girder ◽  
Continuous Girder Bridge ◽  
Key Issues ◽  
Girder Bridge ◽  
Bridge Position

Through the checking comparison of example bridge, to analysis the major causes of the cracking and too much deflection for prestressed concrete continuous box girder bridge. Calculated weak position and the current presence of cracks in the bridge position basically consistent, so cracks mainly caused by the prestress loss, concrete creep and the temperature effect, the structure stiffness weakened after cracking, then the actual mid-span deflection is greater than the calculated values bound. Therefore, the cracking and too much deflection appear simultaneous and mutual promote. The view that by improving the mechanical behavior of box girders, design parameters optimization, just the fundamental solution to cracking and too much deflection, also, several key issues need study to be addressed.

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.

Procedure Inversion Effect Analysis of Final System Transformation of Prestressed Concrete Continuous Girder Bridge

2014 ◽  
Vol 501-504 ◽  
pp. 1323-1327
Author(s):  
Xu Luo ◽  
Lu Rong Cai
Keyword(s):  
Stress Distribution ◽  
Prestressed Concrete ◽  
Steel Beams ◽  
System Transformation ◽  
Box Girder ◽  
Pull Out ◽  
Temporary Support ◽  
Continuous Girder Bridge ◽  
Girder Bridge ◽  
Prestressing Loss

When the cantilever construction is adopted by the prestressed concrete continuous girder bridge, the order of two key procedures between removing temporary support and tensing remanent prestressed cable is used to be ignored. In order to study the influence of procedure inversion, the influences on bridge shape, stress distribution and prestressing loss were calculated for one common prestressed continuous concrete box girder bridge by MIDAS CIVIL 2006, respectively. The obtained result presents that: the influence on the bridge shape and the prestressing loss are not apparent, but the influence on the stress distribution is serious; the maximal compressive stress of procedure inversion is more 42.3% than common construction procedure only by tensing the remaining steel beams at box girder; especially, the combining area between the box girder and temporary support is easy to pull out. So, the procedure inversion construction method cant be accepted.

Mechanical Properties Analysis of CFRP Pre-Stressed Section Continuous Thin-Walled Box Girder Bridge Models 22

2014 ◽  
Vol 624 ◽  
pp. 592-595
Author(s):  
Xin Zhong Wang ◽  
Chuan Xi Li
Keyword(s):  
Prestressed Concrete ◽  
Material Model ◽  
Prestress Loss ◽  
Box Girder ◽  
Concrete Material ◽  
Bridge Model ◽  
Change Trend ◽  
Box Girder Bridge ◽  
Girder Bridge ◽  
Bridge Models

An externally pre-stressed continuous box girder bridge model is designed according to loading features of the continuous beam. The CFRP bars and steel strands are used to make two models for externally pre-stressed reinforcements Analysis of the two models under three different load stiffness and loss of prestress, through calculation and analysis, found that two kinds of prestressed concrete material model under three load deflection basic same, also almost the same change trend, prestressed RMS model than model 1, 2 but with the increase of load model 2 prestress loss is big. Analysis results of CFRP materials and application to provide the reference in the bridge.

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.

scholarly journals Load Distribution In Adjacent Precast "Deck Free" Concrete Box-Girder Bridges

2021 ◽  
Author(s):  
Waqar Khan
Keyword(s):  
Prestressed Concrete ◽  
Precast Concrete ◽  
Box Girders ◽  
Box Girder Bridges ◽  
Box Girder ◽  
Girder Bridges ◽  
Concrete Box Girder ◽  
Concrete Box Girder Bridges ◽  
Girder Bridge ◽  
The Moment

Bridges built with adjacent precast, prestressed concrete box-girders are a popular and economical solution for short-span bridges because they can be constructed rapidly. The top flanges of the precast box girders form the bridge deck surface. A shear key is introduced between the adjacent boxes over the depth of the top flange (i.e. 225 mm thick as the thickness of the box's top flange). Canadian Highway Bridge Design Code, CHBDC specifies empirical equations for the moment and shear distribution factors for selected bridge configurations but not for adjacent precast concrete box-girder bridge type. In this study, a parametric study was conducted, using the 3D finite-element modeling, and a set of simplified equations for the moment, shear and deflection distribution factors for the studied bridge configuration was developed.

scholarly journals Load Distribution In Adjacent Precast "Deck Free" Concrete Box-Girder Bridges

2021 ◽  
Author(s):  
Waqar Khan
Keyword(s):  
Prestressed Concrete ◽  
Precast Concrete ◽  
Box Girders ◽  
Box Girder Bridges ◽  
Box Girder ◽  
Girder Bridges ◽  
Concrete Box Girder ◽  
Concrete Box Girder Bridges ◽  
Girder Bridge ◽  
The Moment

Bridges built with adjacent precast, prestressed concrete box-girders are a popular and economical solution for short-span bridges because they can be constructed rapidly. The top flanges of the precast box girders form the bridge deck surface. A shear key is introduced between the adjacent boxes over the depth of the top flange (i.e. 225 mm thick as the thickness of the box's top flange). Canadian Highway Bridge Design Code, CHBDC specifies empirical equations for the moment and shear distribution factors for selected bridge configurations but not for adjacent precast concrete box-girder bridge type. In this study, a parametric study was conducted, using the 3D finite-element modeling, and a set of simplified equations for the moment, shear and deflection distribution factors for the studied bridge configuration was developed.

Study on Spatial Effect of Wide Box Girders under Unbalance Loading

2013 ◽  
Vol 438-439 ◽  
pp. 1093-1097
Author(s):  
Ke Chen ◽  
Lei Wang
Keyword(s):  
Finite Element ◽  
Prestressed Concrete ◽  
Spatial Effect ◽  
Design Calculation ◽  
Spatial Effects ◽  
Box Girders ◽  
Box Girder ◽  
Space Problem ◽  
Girder Bridge ◽  
Element Method

Prestressed concrete continuous wide box girder bridge is widely used in urban bridges, because of its large width-span ratio, spatial effects from unbalance load cannot be ignored. When the bridge was analyzed by beam element system, the increased coefficient of unbalance loading is used to simplified space problem into plane problem. Spatial effect of wide box girder under unbalance loading is calculated by solid finite element method, and used in a project example in Hangzhou. Comparing analysis results of solid finite element with other simplified methods, it shows that the solid element method is more applicable and accurate. This method and results offer reference for similar bridge design calculation.

Study on Crack Causes and Strengthening Measures of Large Span PC Continuous Box Girder Bridges

2010 ◽  
Vol 163-167 ◽  
pp. 3551-3554
Author(s):  
Wei Peng ◽  
Zhi Xiang Zha
Keyword(s):  
Prestressed Concrete ◽  
Load Test ◽  
Box Girder Bridges ◽  
Element Analysis ◽  
Box Girder ◽  
Girder Bridges ◽  
Long Span ◽  
Concrete Box Girder Bridges ◽  
Girder Bridge ◽  
Engineering Projects

This template Based on cracks observation and finite element analysis of real engineering projects as well as bridge load test after reinforcement, causes and types of cracks in prestressed concrete box girder bridges and treating measurements are systematically studied. The results obtained from the calculation are presented to demonstrate the effect of sensitive factors, such as arrangement of longitudinal prestressed tendons, the magnitude of vertical prestressed force, temperature gradient, etc. The results show that the arrangement of longitudinal prestressed tendons and the magnitude of vertical prestressed force take key roles in cracks control of box girder webs. Lots of treating measurements are presented in accordance with different types of cracks, some of them are applied to a reinforcement engineering of a long span pretressed concrete continuous box girder bridge with cracks. Load test after reinforcement of the bridge demonstrates the reasonability of the treating measurements. Several design recommendations and construction measures about reinforcements and some sensitive factors mentioned above are proposed to control cracks.

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.

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