Load and resistance data for precast stringer highway bridges

2006 ◽  
Vol 33 (11) ◽  
pp. 1368-1378 ◽  
Author(s):  
Daman K Panesar ◽  
F Michael Bartlett
Keyword(s):  
Dynamic Load ◽  
Bending Moment ◽  
Highway Bridges ◽  
Normal Weight ◽  
Unit Weight ◽  
Statistical Parameters ◽  
Concrete Core ◽  
Load Effect ◽  
Reliability Indices ◽  
Resistance Data

Statistical parameters for the load effects and resistances of precast "type G" stringer bridges erected in Alberta since the late 1950s are presented to assist practicing engineers assessing similar bridges using the mean load method. The load effect data include unit weight data for normal weight and two lightweight concretes; traffic volumes, gross vehicle weights, and single, tandem, and tridem axle weights observed on primary, secondary, and local roads; and dynamic load allowances for shear and bending moment on short span bridges. Extreme annual traffic loads are derived. The resistance data include compressive and tensile strengths of normal weight and two lightweight concretes and yield strengths for corroded and uncorroded reinforcing steel. Additional statistical parameters are presented to account for other readily discerned bridge-specific idealization factors that affect the reliability indices. Professional factors for flexural and shear resistance are derived using experimental data reported from past investigations of type G stringers by others.Key words: concrete, core tests, corrosion, dynamic load allowance, material properties, single axles, tandem axles, tridem axles, reliability.

Assessment of precast stringer highway bridges using mean load method

2006 ◽  
Vol 33 (11) ◽  
pp. 1359-1367 ◽  
Author(s):  
Daman K Panesar ◽  
F Michael Bartlett
Keyword(s):  
Bending Moment ◽  
Highway Bridges ◽  
Design Code ◽  
Reliability Indices ◽  
Dynamic Load Allowance ◽  
Bridge Approach ◽  
Specific Factors ◽  
The Mean ◽  
Axle Loads ◽  
Critical Sections

The mean load method of the Canadian Highway Bridge Design Code is used to evaluate the shear and bending moment reliability of existing precast "type G" stringer bridges in Alberta that date from the late 1950s. The overall stringer population is categorized into distinct subpopulations using bridge-specific factors, including the degree of deterioration and approach span condition, which are readily identified during a brief field visit or from inspection reports. Critical sections to be investigated for reliability resisting shear forces or bending moments are determined. The reliability indices decrease if the reinforcement is corroded or the bridge approach is not smooth, and the reduction of the maximum axle loads permitted by legislation due to these factors is quantified. For bridge subpopulations where the actual reliability index is less than the target value for current legal axle loads, the critical axle load for moment is less than that for shear. Therefore, if flexural distress is not noted during inspection of such structures, they are likely adequate for the actual loading they are subjected to.Key words: corrosion, deterioration, dynamic load allowance, mean load method, reliability, visual inspection.

scholarly journals Development of heavy truck models and their effects on girder bridges

2021 ◽  
Author(s):  
Lang Liu ◽  
◽  
Lexian Zhang ◽  
Jie Wang ◽  
Hong Yang ◽  
...  
Keyword(s):  
Bending Moment ◽  
Highway Bridges ◽  
Load Effect ◽  
Girder Bridges ◽  
Heavy Trucks ◽  
Bridge Model ◽  
Potential Factor ◽  
Heavy Truck ◽  
Beam Bridge ◽  
T Beam

The traffic on highway bridges has been increasing in both volume and magnitude, which even has become one of the main reasons leading to damages and collapse of bridges. Most of the existing regulations for overloading checking are carried out based on various limits of gross vehicle weights and axle loads. However, the results of relevant researches show that weight is only a potential factor but not the dominating factor in threatening the safety of bridges. In this study, the concept of load-effect-based heavy truck is proposed for overloading checking, and then three years of WIM data were collected and used to develop heavy truck models for each truck type, based on the understanding of the characteristics and configurations of heavy trucks as well as the distribution of their main parameters. Furthermore, the typical heavy truck models selected and their possible combinations are applied to a simply supported pre-stressed concrete T-beam bridge model with three loading levels, considering one-lane, two-lane and three-lane loaded respectively, then the induced load effect, deflection and stress are discussed for 20 loading cases. The results show the bending moment caused by heavy trucks moving on multiple lanes is 1.6 times the value of the standard truck model in Chinese specification, and the eccentric loading due to a very heavy vehicle moving on single lane usually lead to more severe effect.

scholarly journals Development of Brazilian highway live load model for unlimited fatigue life

2020 ◽  
Vol 13 (4) ◽  
Author(s):  
Anselmo Leal Carneiro ◽  
Enson de Lima Portela ◽  
Túlio Nogueira Bittencourt
Keyword(s):  
Fatigue Life ◽  
Bending Moment ◽  
Highway Bridges ◽  
Live Load ◽  
Box Girders ◽  
Load Effect ◽  
Load Model ◽  
Weigh In Motion ◽  
Bias Factor ◽  
Live Load Model

Abstract This work studies the fatigue live load model used in Brazil for highway bridges. Using the unlimited fatigue life approach, the current live load model is evaluated in relation to the actual traffic and a new fatigue live load model is proposed. Weigh-in-motion (WIM) stations data on two important Brazilian highways are used. The main structural analysis performed in this paper consider the bridges as box girders or multiple girders. The ratio between real traffic and the live load model load effect (bias factor) are determined for single and continuous spans in terms of bending moment and shear force. It is found that the bias factor of the current live load can vary a lot and may not ensure unlimited fatigue life. The proposed model, on the other hand, presents more uniform bias factors and is in accordance with the unlimited fatigue life approach for the WIM data.

Safe Platooning Headways on Girder Bridges

2021 ◽  
pp. 036119812110363
Author(s):  
Bowen Yang ◽  
Joshua S. Steelman ◽  
Jay A. Puckett ◽  
Daniel G. Linzell
Keyword(s):  
Prestressed Concrete ◽  
Limit State ◽  
Live Load ◽  
Load Effect ◽  
Operational Strategies ◽  
Reliability Indices ◽  
Girder Bridges ◽  
Legal Limits ◽  
Weigh In Motion ◽  
Load And Resistance Factor

Truck platooning—digitally linking two or more trucks to travel in a closely spaced convoy—is an emerging technology with the potential to save fuel and reduce labor. A framework is described to determine how much a platoon permit load might be increased above Federal Bridge Formula B legal limits, given strict control over the load characteristics and operational tactics. Soon, platoons are expected to advance not only with respect to traffic operations but also in their ability to weigh and report axle weight and spacing, functioning as mobile weigh-in-motion vehicles. Consequently, platoon live load statistics (bias and coefficient of variation) can differ from code assumptions, and are perhaps controllable, which poses a significant opportunity with respect to operational strategies. A parametric study is presented that examined safe headways between platooning trucks, considering different girder spacings, span lengths, numbers of spans, types of structure, truck configurations, numbers of trucks, and adjacent lane loading scenarios. The Strength I limit state was evaluated for steel and prestressed concrete I-girder bridges optimally designed using load and resistance factor design. Reliability indices, β, were calculated for each load case based on Monte Carlo simulation. Summary headway guidance was developed and is presented here to illustrate potential safe operational strategies for varying truck weights and platoon live load effect uncertainties.

Dynamic Load Allowances Corresponding to Different Responses in Various Sections of Highway Bridges to Moving Vehicular Loads

2015 ◽  
Vol 18 (10) ◽  
pp. 1685-1701 ◽  
Author(s):  
Qingfei Gao ◽  
Zonglin Wang ◽  
Chan Ghee Koh ◽  
Chuang Chen
Keyword(s):  
Dynamic Load ◽  
Highway Bridges

Improvement of extrapolation of traffic load effect on highway bridges based on Rice’s theory

2015 ◽  
Vol 15 (3) ◽  
pp. 527-539 ◽  
Author(s):  
Weizhen Chen ◽  
Cheng Ma ◽  
Zhenlin Xie ◽  
Bochong Yan ◽  
Jun Xu
Keyword(s):  
Highway Bridges ◽  
Traffic Load ◽  
Load Effect ◽  
Rice’S Theory

Study on Dynamic Response of Hollow Pile Using the Method of Composite Stiffness Principle and Biparameter

2011 ◽  
Vol 243-249 ◽  
pp. 2679-2683
Author(s):  
Yong Mou Zhang ◽  
Min Yang ◽  
Qiang Gang Yan
Keyword(s):  
Dynamic Load ◽  
Bending Moment ◽  
Dynamic Loads ◽  
Concrete Pile ◽  
Side Resistance ◽  
Geological Conditions ◽  
Internal Forces ◽  
The Finite Difference Method ◽  
Composite Stiffness ◽  
Laterally Loaded

The method of composite stiffness principle and biparameter for laterally loaded pile was used in this paper to calculate the amplitude of deflection and rotation of pile on the ground when the vibration frequency of dynamic load is equal to or close to the natural frequency of pile, i.e. when the pile is in the state of resonance. And the amplitude of the maximum bending moment and its location was also calculated. Then the finite difference method which is simple in principle and easy to program was used to calculate the displacement, soil side resistance and internal forces of pile under horizontal dynamic load. By choosing reasonable parameters, rotation, displacement, and the maximum bending moment of hollow concrete pile and solid pile under the same dynamic loads at pile top in the same geological conditions were calculated respectively. On this basis, the performance differences between hollow pile and solid pile were analyzed. Some advantages of hollow pile were obtained. This research provides a theoretical guidance for the using of hollow pile in engineering.

The Natural Bending Vibration of the Continuous Beam and the Impact Factor of Bridge

2011 ◽  
Vol 90-93 ◽  
pp. 1245-1249 ◽  
Author(s):  
Xiang Rong Yuan
Keyword(s):  
Impact Factor ◽  
Impact Force ◽  
Bending Moment ◽  
Highway Bridges ◽  
Mode Shapes ◽  
Impact Factors ◽  
Beam Model ◽  
Continuous Beam ◽  
The Impact ◽  
Selection Of

The natural frequencies and mode shapes of 2, 3 and 4 spans continuous beam with universal cross section are calculated, and these dynamic parameters of 2 spans continuous beam model are measured. From the analysis and the model test, the locations of the maximum curvatures of the mode shapes are determined, and comparing that with the maximum bending moment of the beam under the action of uniformly distributed load, the selection of the natural frequency of the beam is discussed with the General Code for Design of Highway Bridges and Culverts as the impact factors of the beam is calculated. It is shown from the results of the analysis and the test that, for the impact factor, when the effect of positive bending moment caused by impact force is calculated, the fundamental frequency must be used as shown in the General Code, and the 2nd or 3rd frequency must be used when the effect of negative bending moment caused by impact force is calculated. The selection of the frequency should be combined with the mode shape into account for the specific circumstances.

Preliminary design of standard CPCI prestressed bridge girders by linear programming

1985 ◽  
Vol 12 (1) ◽  
pp. 213-225 ◽  
Author(s):  
Sami M. Fereig
Keyword(s):  
Linear Programming ◽  
Prestressed Concrete ◽  
Programming Model ◽  
Concrete Strength ◽  
Bending Moment ◽  
Highway Bridges ◽  
Concrete Bridges ◽  
Preliminary Design ◽  
Concrete Girders ◽  
Prestressing Force

The design of prestressed concrete bridges using standard CPCI (Canadian Prestressed Concrete Institute) girders is generally done by trial and error, requiring extensive computation. This study will use a linear programming mathematical model to establish preliminary design charts for such cases and to obtain the required prestressing force after losses for a given CPCI bridge interior girder with different spans and spacings. The bridge is designed to carry the MS200-77 loading, and the design conforms with the Canadian Standards Association CAN3-S6-M79 for design of highway bridges. The bridge considered is single-span, with a cast in situ concrete deck acting compositely with the prestressed girders under live load. The linear programming model is also used to determine the design criteria that will control the design for the cases investigated, and to perform the parametric study to evaluate the effect of variations in deck thickness, girder concrete strength, and prestressing losses on the value of the required prestressing force. Key words: bending moment, concrete, girders, highway bridges, linear programming, load, prestressing, span.

Study on Statistical Parameters of Resistance of Steel Highway Bridge Reliability Design in China

2010 ◽  
Vol 163-167 ◽  
pp. 3324-3327 ◽  
Author(s):  
Kun Li
Keyword(s):  
Design Method ◽  
Limit State ◽  
Highway Bridges ◽  
Calculation Model ◽  
Highway Bridge ◽  
Statistical Parameters ◽  
Probability Limit ◽  
Reliability Design ◽  
Structure Reliability ◽  
Bridge Reliability

The coming national specification for steel highway bridge will adopt the design method of probability limit state based on the structure reliability theory. Then the statistical parameters of loads and resistance play a key role in this method. Based on the extensive survey and investigation on site, the parameters of resistance are calculated in the study. In the work, three aspects of resistance’s uncertainty which are the uncertainty of materials properties, geometric parameters of members and calculation model are analyzed respectively. Then, the statistical parameters of five typical members of two commonly used steels—Q235q and Q345qD—in steel highway bridges are calculated. The recommended statistical parameters of resistance of steel highway bridge can be a reference for the new specification.

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