scholarly journals Unified approach for bridge deck design

2021 ◽  
Author(s):  
Karim Meleka
Keyword(s):  
Bridge Deck ◽  
Flexural Rigidity ◽  
Single Point ◽  
Point Load ◽  
Live Load ◽  
Design Code ◽  
Design Alternatives ◽  
Wheel Loading ◽  
Torsionally Stiff ◽  
Concrete Deck

Current Canadian Highway Bridge Design Code includes design provisions to establish live load demands in (i) reinforced concrete decks over longitudinal girders, (ii) orthotropic deck over longitudinal girders, and (iii) orthotropic deck over transverse beams. However, it only provides an equation for factored applied moment on concrete deck under single point load. Similar equations for orthotropic decks are as yet unavailable. As such, parametric study was conducted to lead to new empirical expressions for moment in bridge decks subjected to truck wheel loading considering each of the three cases of orthotropy: (i) relatively torsionally stiff, flexurally soft decks; (ii) relatively uniformly thick decks; and (iii) relatively torsionally soft, flexurally stiff decks. Using the proposed formulations, bridge deck design can be treated in a unified way across different deck types, accounting for longitudinal-transverse flexural rigidity of decks. Application of these methods can significantly simplify the analysis of decks and allow bridge engineers to make comparisons across different deck design alternatives.

scholarly journals Unified approach for bridge deck design

2021 ◽  
Author(s):  
Karim Meleka
Keyword(s):  
Bridge Deck ◽  
Flexural Rigidity ◽  
Single Point ◽  
Point Load ◽  
Live Load ◽  
Design Code ◽  
Design Alternatives ◽  
Wheel Loading ◽  
Torsionally Stiff ◽  
Concrete Deck

Current Canadian Highway Bridge Design Code includes design provisions to establish live load demands in (i) reinforced concrete decks over longitudinal girders, (ii) orthotropic deck over longitudinal girders, and (iii) orthotropic deck over transverse beams. However, it only provides an equation for factored applied moment on concrete deck under single point load. Similar equations for orthotropic decks are as yet unavailable. As such, parametric study was conducted to lead to new empirical expressions for moment in bridge decks subjected to truck wheel loading considering each of the three cases of orthotropy: (i) relatively torsionally stiff, flexurally soft decks; (ii) relatively uniformly thick decks; and (iii) relatively torsionally soft, flexurally stiff decks. Using the proposed formulations, bridge deck design can be treated in a unified way across different deck types, accounting for longitudinal-transverse flexural rigidity of decks. Application of these methods can significantly simplify the analysis of decks and allow bridge engineers to make comparisons across different deck design alternatives.

Employing Surface Roughness for Bridge-Vehicle Interaction Based Damage Detection

2011 ◽  
Author(s):  
Vesna Jaksic ◽  
Vikram Pakrashi ◽  
Alan O’Connor
Keyword(s):  
Surface Roughness ◽  
Damage Detection ◽  
Flexural Rigidity ◽  
Single Point ◽  
Point Load ◽  
Ride Quality ◽  
Breathing Crack ◽  
Bernoulli Beam ◽  
Statistical Parameters ◽  
Euler Bernoulli Beam

Damage detection and Structural Health Monitoring (SHM) for bridges employing bridge-vehicle interaction has created considerable interest in recent times. In this regard, a significant amount of work is present on the bridge-vehicle interaction models and on damage models. Surface roughness on bridges is typically used for detailing models and analyses are present relating surface roughness to the dynamic amplification of response of the bridge, the vehicle or to the ride quality. This paper presents the potential of using surface roughness for damage detection of bridge structures through bridge-vehicle interaction. The concept is introduced by considering a single point observation of the interaction of an Euler-Bernoulli beam with a breathing crack traversed by a point load. The breathing crack is treated as a nonlinear system with bilinear stiffness characteristics related to the opening and closing of crack. A uniform degradation of flexural rigidity of an Euler-Bernoulli beam traversed by a point load is also considered in this regard. The surface roughness of the beam is essentially a spatial representation of some spectral definition and is treated as a broadband white noise in this paper. The mean removed residuals of beam response are analyzed to estimate damage extent. Uniform velocity and acceleration conditions of the traversing load are investigated for the appropriateness of use. The detection and calibration of damage is investigated through cumulant based statistical parameters computed on stochastic, normalized responses of the damaged beam due to passages of the load. Possibilities of damage detection and calibration under benchmarked and non-benchmarked cases are discussed. Practicalities behind implementing this concept are also considered.

Investigation of an externally restrained concrete bridge deck slab on a multi-girder bridge model

2011 ◽  
Vol 38 (2) ◽  
pp. 233-241 ◽  
Author(s):  
John Newhook ◽  
Judy Gaudet ◽  
Rahman Edalatmanesh
Keyword(s):  
Bridge Deck ◽  
Single Point ◽  
Point Load ◽  
Concrete Bridge ◽  
Simultaneous Application ◽  
Bridge Model ◽  
Deck Slabs ◽  
Concrete Bridge Deck ◽  
Girder Bridge ◽  
Deck Slab

The steel-free bridge deck system is an innovative solution in which the concrete deck slab is externally restrained by a series of steel straps. The ultimate strength characteristics of externally reinforced concrete bridge deck slabs were investigated in this paper. A 1/3 scale experimental model of a bridge with six girders was constructed for the study. This was the first known set of test results on a bridge model with more than four girders. A single point load, simulating the dual tire print of the CHBDC design truck, was applied at various locations on the deck and loading increased until punching failure occurred. The influence of different parameters including transverse diaphragms, proximity for the load to restraint straps, residual strength after strap removal, and simultaneous application of wheel loads in adjacent panels of the deck was tested to obtain a comprehensive understanding of the resistance of this deck system. The testing results confirmed that the interior panels of the deck have inherently higher punching resistance than the exterior panels. Most significantly, the study provided significant statistical data on the punching resistance of these deck slabs.

Application of a simplified method of calculating longitudinal moments to the Ontario highway bridge design code

1979 ◽  
Vol 6 (1) ◽  
pp. 36-50 ◽  
Author(s):  
Baidar Bakht ◽  
M. S. Cheung ◽  
T. S. Aziz
Keyword(s):  
Orthotropic Plate ◽  
Concrete Beams ◽  
Plate Theory ◽  
Highway Bridge ◽  
Live Load ◽  
Design Code ◽  
Worked Example ◽  
Development Methodology ◽  
Simplified Method ◽  
Torsionally Stiff

A manual method for calculating the design live load longitudinal moments in superstructures of most right bridges is presented. The bridge types that can be analysed by this method are: slab bridges, beam and slab bridges incorporating both steel and concrete beams, bridges incorporating wooden beams, and slabs on hollow trapezoidal or other such torsionally stiff beams.The proposed method was developed by orthotropic plate theory, and was checked by the grillage analogy method. The basis of the method and details of development methodology are presented. The effect of the various parameters on the transverse distribution of longitudinal moments is discussed.The method is useful not only for the ease with which design longitudinal moments can be obtained, but also because it enables the designer to investigate the effects of making changes in the design on distribution characteristics.To demonstrate the simplicity of the solution a worked example is included.

Comparative Evaluation of Crack Width for Reinforced Concrete Bridge Deck

2021 ◽  
Vol 9 (10) ◽  
pp. 59-67
Author(s):  
Shivank Tamrakar
Keyword(s):  
Reinforced Concrete ◽  
Crack Width ◽  
Bridge Deck ◽  
Constant Width ◽  
Bridge Decks ◽  
Concrete Bridge ◽  
Live Load ◽  
Reinforced Concrete Bridge ◽  
Concrete Bridge Decks ◽  
Reinforcement Bar

Abstract: Cracking in reinforced concrete bridge decks is a massively concern in the India. Many concrete bridge decks, inobservant to the age of construction, have shown different levels and patterns of cracking. Not only does cracking of bridge decks weaken the bridge infrastructure, but also allows the inflow of corrosive agents into the reinforcement. In this study, the crack width evaluation of RC bridge deck of span of 5 m. and 9 m. is based on equations given by IRS Concrete Bridge Code 1997 for different cases like- the effect of depth variation, reinforcement diameter, clear cover, variation in live load moment, spacing of tension reinforcement and different no. of tension reinforcement bar to constant width for the same crosssection. This study concluded that crack width increases with increase in clear cover, variation in live load moment and spacing of tension reinforcement while it decreases with increase in reinforcement diameter, depth of the bridge deck and number of reinforced bars and percentage change evaluation of different parameter of 5m and 9m span bridge deck. Keyword: Crack Width, Cracking, Bridge Deck Slab, Crack Spacing.

scholarly journals A Planar Parallel Device for Neurorehabilitation

Robotics ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 104
Author(s):  
Jawad Yamine ◽  
Alessio Prini ◽  
Matteo Lavit Nicora ◽  
Tito Dinon ◽  
Hermes Giberti ◽  
...  
Keyword(s):  
Single Point ◽  
Point Load ◽  
Experimental Procedure ◽  
Rehabilitation Robots ◽  
Parallel Kinematic Mechanism ◽  
Kinematic Behaviour ◽  
3D Printed ◽  
Parallel Kinematic ◽  
Robotic Devices ◽  
Kinematic Optimization

The patient population needing physical rehabilitation in the upper extremity is constantly increasing. Robotic devices have the potential to address this problem, however most of the rehabilitation robots are technically advanced and mainly designed for clinical use. This paper presents the development of an affordable device for upper-limb neurorehabilitation designed for home use. The device is based on a 2-DOF five-bar parallel kinematic mechanism. The prototype has been designed so that it can be bound on one side of a table with a clamp. A kinematic optimization was performed on the length of the links of the manipulator in order to provide the optimum kinematic behaviour within the desired workspace. The mechanical structure was developed, and a 3D-printed prototype was assembled. The prototype embeds two single-point load cells to measure the force exchanged with the patient. Rehabilitation-specific control algorithms are described and tested. Finally, an experimental procedure is performed in order to validate the accuracy of the position measurements. The assessment confirms an acceptable level of performance with respect to the requirements of the application under analysis.

scholarly journals Interlaminar Bonding Properties on Cement Concrete Deck and Phosphorous Slag Asphalt Pavement

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1427 ◽  
Author(s):  
Guoping Qian ◽  
Shunjun Li ◽  
Huanan Yu ◽  
Xiangbing Gong
Keyword(s):  
Bridge Deck ◽  
Asphalt Pavement ◽  
Asphalt Mixture ◽  
Fine Aggregate ◽  
Cement Concrete ◽  
Bonding Properties ◽  
The Impact ◽  
Phosphorous Slag ◽  
Bridge Deck Pavement ◽  
Concrete Deck

The slippage damage caused by weak interlaminar bonding between cement concrete deck and asphalt surface is a serious issue for bridge pavement. In order to evaluate the interlaminar bonding of cement concrete bridge deck and phosphorous slag (PS) asphalt pavement, the shear resistance properties of the bonding layer structure were studied through direct shear tests. The impact of PS as a substitute of asphalt mixture aggregate, interface characteristics, normal pressure, waterproof and cohesive layer types, temperature and shear rate on the interlaminar bonding properties were analyzed. The test results indicated that the interlaminar bonding of bridge deck pavement is improved after asphalt mixture fine aggregate was substituted with PS and PS powder, and the result indicated that the shear strength of grooved and aggregate-exposed interfaces is significantly higher than untreated interface, the PS micro-powder or anti-stripping agent can also improve the adhesion between layers when mixed into SBS asphalt. This study provided important theoretical and practical guidance for improving the shear stability of bridge deck pavement.

Limit Analysis and Yield-Line Theory

1968 ◽  
Vol 35 (2) ◽  
pp. 357-362 ◽  
Author(s):  
Antoni Sawczuk ◽  
P. G. Hodge
Keyword(s):  
Limit Analysis ◽  
Single Point ◽  
Point Load ◽  
Simply Supported ◽  
Yield Line ◽  
Yield Line Theory ◽  
Line Theory ◽  
The Relationship ◽  
Line Analysis ◽  
General Method

The relationship between limit analysis and yield-line analysis is investigated. Attention is restricted to simply supported, isotropic slabs subjected to single-point loadings. It is found that conventional yield-line analyses quite often give substantial overestimates of the carrying capacity. A general method is formulated for finding the yield-point load, and various examples are considered.

Sign in / Sign up

Export Citation Format

Share Document