scholarly journals Acoustic Emission Monitoring of Multicell Reinforced Concrete Box Girders Subjected to Torsion

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Marya Bagherifaez ◽  
Arash Behnia ◽  
Abeer Aqeel Majeed ◽  
Chai Hwa Kian
Keyword(s):  
Acoustic Emission ◽  
Reinforced Concrete ◽  
Cross Sections ◽  
Analysis Data ◽  
Damage Localization ◽  
Box Girders ◽  
Box Girder ◽  
Value Analysis ◽  
Damage Propagation ◽  
Torsion Fracture

Reinforced concrete (RC) box girders are a common structural member for road bridges in modern construction. The hollow cross-section of a box girder is ideal in carrying eccentric loads or torques introduced by skew supports. This study employed acoustic emission (AE) monitoring on multicell RC box girder specimens subjected to laboratory-based torsion loading. Three multicell box girder specimens with different cross-sections were tested. The aim is to acquire AE analysis data indicative for characterizing torsion fracture in the box girders. It was demonstrated through appropriate parametric analysis that the AE technique could be utilized to effectively classify fracture developed in the specimens for describing their mechanical behavior under torsion. AE events localization was presented to illustrate the trend of crack and damage propagation in different stages of fracture. It could be observed that spiral-like patterns of crack were captured through AE damage localization system and damage was quantified successfully in different stages of fracture by using smoothedb-value analysis.

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 Structural condition assessment of reinforced-concrete bridges based on acoustic emission and strain measurements

2020 ◽  
Vol 10 (5) ◽  
pp. 1037-1055
Author(s):  
Imane Bayane ◽  
Eugen Brühwiler
Keyword(s):  
Acoustic Emission ◽  
Reinforced Concrete ◽  
Concrete Slab ◽  
Structural Condition ◽  
Concrete Bridges ◽  
Reinforced Concrete Slab ◽  
Value Analysis ◽  
Operational Conditions ◽  
Emission Activity ◽  
Structural Condition Assessment

Abstract A reliable novel monitoring approach is developed to assess the structural condition of reinforced-concrete bridge elements. The approach is based on combining acoustic emission technique and strain gauge measurements, and it is illustrated by a case study of a composite steel–concrete viaduct in service since 1957. Monitoring was performed on its reinforced-concrete deck slab under traffic and environmental loading for one year. The monitoring setup and procedure are presented. The variation of acoustic emission signals is evaluated regarding strain and temperature measurements. Parametric study, pencil-break test, statistical analysis, crack classification and b-value analysis are performed to assess the structural condition. The acoustic emission activity of the reinforced-concrete slab is evaluated for 1 year under operational conditions. From the monitoring approach, it was possible to identify the nature of the cracking activity in the concrete slab as a function of traffic loading and temperature and to assess in time the condition of the slab-girder connection.

scholarly journals Protective and Blast Resistive Design of Posttensioned Box Girders Using Computational Geometry

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Majid Aleyaasin
Keyword(s):  
Computational Geometry ◽  
Cross Section ◽  
Cross Sections ◽  
Computational Algorithm ◽  
Optimal Shape ◽  
Box Girders ◽  
Cross Point ◽  
Box Girder ◽  
Numerical Example ◽  
Duct Geometry

The optimal tendon profile and its associated duct geometry for posttensioned box girders are investigated. A computational algorithm has been developed to determine an ideal shape for the tendon and duct. The algorithm is based on a diagonal cross point in the Magnel quadrilateral and uses computational geometry instead of graphical drawing. Thereafter, an ideal parabolic and linear tendon profiles can be calculated from which the covering duct could be shaped. To check the optimality of the results, an automatic examination of Magnel diagrams in various cross sections is incorporated in the algorithm. This enables a unique prestress level to be selected that suits all sections. Then, the mideccentricity of the two crossing points with a common prestress line is chosen as a design eccentricity in each cross section. The optimal duct shape is determined based on such automatic inspections. In a numerical example, the linear, parabolic, and optimal duct geometries are compared and drawn. It is concluded that both linear and parabolic duct shapes can be very close to an optimal shape. In a numerical example, an optimal, box girder with linear open access-type tendons is designed that can withstand extra blast load when explosion occurs.

scholarly journals Experimental Study of the Structural Behaviour of Reinforced Concrete Box Girder with the Using of Steel Plates Strengthening and Different Shapes of Cells

2021 ◽  
Vol 14 (1) ◽  
pp. 86-95
Author(s):  
Zahraa Sermed Zuhdiy ◽  
Ali Laftah Abbas
Keyword(s):  
Reinforced Concrete ◽  
Crack Width ◽  
Ultimate Load ◽  
Steel Plates ◽  
Structural Behaviour ◽  
Box Girders ◽  
Box Girder ◽  
Rectangular Cell ◽  
Circular Cell ◽  
Concrete Box Girder

The aim of this research is to study the effect of using corrugated steel plate strengthening on the structural behaviour of reinforced concrete box girder by using corrugated steel plates with vertical and horizontal corrugation and studying the effect of the shape of cells by using rectangular and circular shape with the same web width and strengthening the circular cell with smooth plate. Five simply supported reinforced concrete box girders are casted by using Self-compacting concrete and experimentally tested under four-point load. The box girder specimens are divided into two groups according to the steel strengthening and the shape of cells. The experimental results showed that in the first group, the using of the vertical and horizontal corrugated steel plates strengthening increased the ultimate load by (7.14% and 11.03%) respectively compared with the control box girder, and decreased the crack width, the results also showed that in the second group, the using of circular cell and circular strengthened cell increased the ultimate load by (17.85% and 29.22%) respectively compared with the control box girder with rectangular cell and decreased the crack width. All the box girders in the first and second group failed with diagonal shear.

Influence of Antisymmetrical Actions at Reinforced Concrete Cable-Stayed Bridge

2017 ◽  
Vol 738 ◽  
pp. 3-14 ◽  
Author(s):  
Ivan Balaz ◽  
Yvona Kolekova ◽  
Michal Kovac ◽  
Ivana Veghova
Keyword(s):  
Czech Republic ◽  
Reinforced Concrete ◽  
Beam Theory ◽  
Box Girders ◽  
Cross Sectional ◽  
Box Girder ◽  
Cable Stayed Bridge ◽  
Internal Forces ◽  
Theory Calculation ◽  
Generalized Beam Theory

Calculation of the cross-sectional properties of the concrete box-girder with two-cells using Vlasov`s theory and Generalized Beam Theory. Calculation of the internal forces of the St. Venant torsion, the warping torsion, the antisymmetrical and the symmetrical distortion on the basis analogy with beam on the elastic foundation loaded by transverse actions and tension force at the end of the beam. Creating of influence lines of torsion, antisymmetrical distortion and symmetrical distortion internal forces of large concrete cable-stayed bridge with continuous box-girders with two spans. The application for real reinforced concrete Harp bridge over pond Jordán near Tábor in Czech Republic is investigated. Evaluation of internal lines for action according to Eurocode EN 1991-2.

Acoustic emission by steel fiber reinforced concrete under tensile damage

2017 ◽  
Vol 59 (7-8) ◽  
pp. 653-660 ◽  
Author(s):  
Wang Yan ◽  
Ge Lu ◽  
Chen Shi Jie ◽  
Zhou Li ◽  
Zhang Ting Ting
Keyword(s):  
Acoustic Emission ◽  
Reinforced Concrete ◽  
Steel Fiber ◽  
Fiber Reinforced Concrete ◽  
Fiber Reinforced ◽  
Steel Fiber Reinforced Concrete ◽  
Tensile Damage

Dimension and Frequency Profiles of Concrete Highway Bridges in New Madrid Region of Southeastern Missouri

1997 ◽  
Vol 1594 (1) ◽  
pp. 84-93 ◽  
Author(s):  
Ralph Alan Dusseau
Keyword(s):  
Reinforced Concrete ◽  
Concrete Slab ◽  
Highway Bridges ◽  
Ambient Vibration ◽  
Earthquake Hazards ◽  
Empirical Formulas ◽  
Reinforced Concrete Slab ◽  
Box Girder ◽  
Bridge Spans ◽  
New Madrid

The results of a study funded by the U.S. Geological Survey as part of the National Earthquake Hazards Reduction Program are presented. The first objective of this study was the development of a database for all 211 highway bridges along I-55 in the New Madrid region of southeastern Missouri. Profiles for five key dimension parameters (which are stored in the database) were developed, and the results for concrete highway bridges are presented. The second objective was to perform field ambient vibration analyses on 25 typical highway bridge spans along the I-55 corridor to determine the fundamental vertical and lateral frequencies of the bridge spans measured. These 25 spans included six reinforced concrete slab spans and two reinforced concrete box-girder spans. The third objective was to use these bridge frequency results in conjunction with the dimension parameters stored in the database to develop empirical formulas for estimating bridge fundamental natural frequencies. These formulas were applied to all 211 Interstate highway bridges in southeastern Missouri. Profiles for both fundamental vertical and lateral frequencies were then developed, and the results for concrete highway bridges are presented.

Sign in / Sign up

Export Citation Format

Share Document