Concrete Girder Bridges Research Articles

Analysis and Design of Superstructure of Bridge Built Through Engineering College Premises

Abstract: The earlier publication from the authors focused on “The bridge through the college” which highlights how contracts and agreements signed many decades ago have to still be respected and fulfilled. A public highway planned to originally be laid on top of a filled-out irrigation canal passing through the campus of a college that commenced in 1977 was later replaced with an elevated bridge that was completed in 2023 and is now open to the public. The first part of the two-stage manuscript elaborated on the conception of the bridge, the general layout, geometry, and construction of this reinforced concrete girder bridge. The challenges associated in the process of engineering and construction as well as the opportunities missed were discussed. The second part of this study details the analysis process of the girders, the static and dynamic bridge loads considered, the code specifications and guidelines followed. The results of the analyses present the strength and service level member forces the bridge girders and slab are subjected to, and the design governing load combination envelopes. The study presents the superstructure girder designs, slab designs and the design methodology followed overall.

Experimental Investigation on Nonlinear Flexural Behavior of Post-Tensioned Concrete Bridge Girders with Different Grouting Conditions and Prestress Levels

Experimental Investigation on Nonlinear Flexural Behavior of Post-Tensioned Concrete Bridge Girders with Different Grouting Conditions and Prestress Levels

Influence of strand rupture on flexural behavior of reduced-scale prestressed concrete bridge girders with different prestressing levels

In prestressed concrete (PC) bridges, high-strength prestressing steel plays a key role in the flexural response of girders. In both pre-stressed and post-tensioned PC bridge girders, damage induced by corrosion or impact of under-passing high vehicles may led to rupture of one or more strands, significantly affecting the load-carrying capacity against dead and traffic loads. This paper presents an experimental study on the response of PC girders affected by strand rupture at different locations. Four reduced-scale post-tensioned concrete girders with different levels of initial prestressing force were tested under four-point bending. Two specimens with a different level of prestress were initially tested in undamaged configuration to provide a basis for the assessment of damage effects. The other pair of specimens were intentionally damaged - having the same initial prestressing level of their undamaged counterparts - in the lower tendon to investigate their limited flexural response under different performance levels including serviceability and collapse. Damage turned into a different critical cross section outside the loading region, i.e. both cracking and collapse were attained 1.1m away from midspan. In the last section of the paper, a cross sectional analysis of the girder was developed at cracking and ultimate conditions for the prediction of damage impact on failure mechanisms, thus validating the experimental findings.

Finite-Element Performance Degradation Behavior of a Suspension Prestressed Concrete Arch Bridge with Grouting Defects

In response to the difficulty in effectively dealing with grouting defects in corrugated pipes within a suspension prestressed concrete arch bridge, a method for assessing the deterioration in the performance of prestressed concrete girders afflicted with grouting defects was established in the present study. Specifically, a time-varying model of steel strand corrosion within grouting defects was constructed by investigating the corrosion theory of steel strands. In addition, a full-scale numerical simulation model of the long-span prestressed concrete bridge was established based on a practical project. Through the described means, the long-term impact of steel strand corrosion at various locations, lengths, and quantities on the vertical displacement and axial stress of girders was elucidated. The results reveal that in the presence of corrosion affecting 16 steel strands located in the midspan bottom plate, a vertical displacement alteration of 17.55 mm was observed in the midpoint region of the girder over a 30-year period following the bridge’s construction. Further, when considering the combined effects of concrete shrinkage, creep, and the corrosion of 16 steel strands in the midspan bottom plate, the axial compressive stress within the midpoint region of the girder decreased from an initial 6.30 MPa to 0.79 MPa over the same 30-year timeframe post-construction. It was observed that two indicators of vertical displacement and axial stress can be employed to evaluate the performance degradation of prestressed concrete bridge girders with grouting defects. The present findings may provide a reference for the operation and management of bridges with grouting defects.

Grillage Analysis of Prestressed Concrete Girder Deck Superstructure for NH-16 Bridge Flyover; Part-1

Abstract: The bridge superstructure flyover built on National Highway route 16 (NH-16) near Benz circle in Vijayawada to act as grade separated highway for vehicles to cross over National Highway route 65 (NH-65) is made of precast and post-tensioned concrete girders. This article is the first part of the two phase study that focuses on the structural analyses of concrete bridge girders. The bridge girders are analyzed for vehicular loads considered as per Indian Roads Congress Specifications. The IRC Class of loads of 70R and Class A and their wheel load configurations are discussed. The bridge girders along with deck are modeled as grillage girder-slab members in Staad Pro analysis software. The bending moments and shear forces are computed for each of the IRC vehicular load configurations and the envelope forces for governing load configuration are presented for each of the girders. Finally, the article summarizes the maximum flexural and shear demands on the bridge girders. The pros and cons of grillage analysis modeling for prestressed girders and the alternate superior options for precise but quick modeling are also recommended.

Exploring the Effect of Near-Field Ground Motions on the Fragility Curves of Multi-Span Simply Supported Concrete Girder Bridges

Investigating the impact of near-field ground motions on the fragility curves of multi-span simply supported concrete girder bridges is the main goal of this paper. Fragility curves are valuable tools for evaluating seismic risks and vulnerabilities of bridges. Numerous studies have investigated the impact of ground motions on the fragility curves of bridges. Ground motions are commonly categorized into two sets, based on the distance of the recorded station from the seismic source: far-field and near-field. Studies examining the influence of near-field records on bridge fragility curves vary depending on the specific bridge type and type of fragility curve being analyzed. Due to the widespread use of multi-span simply supported concrete girder bridges in the Central and Southeastern United States, this study makes use of this bridge type. This research investigates the component fragility curves for column curvatures, bearing deformations, and abutment displacements by employing 3-D analytical models and conducting nonlinear time history analysis. These curves illustrate the impact of near-field ground motions on different components. The component fragility curves for two sets of records, 91 near-field ground motions and 78 far-field ground motions, were obtained and compared. These findings demonstrate that near-field ground motions have a greater damaging effect on columns and abutments than far-field earthquakes. When it comes to bearing deformations, the far-field earthquake impact is more severe at lower intensities, whereas the impact of the near-field ground motion is stronger at higher intensities.

Fragility Assessment of a Long-Unit Prestressed Concrete Composite Continuous Girder Bridge with Corrugated Steel Webs Subjected to Near-Fault Pulse-like Ground Motions Considering Spatial Variability Effects

Prestressed concrete composite girder bridges with corrugated steel webs (PCCGBCSWs) are extensively employed in bridge construction because of their low dead weight, fast construction, and high prestressing efficiency. Moreover, PCCGBCSWs will experience deformation and failure of the corrugated steel webs, including steel fatigue and fracture, during earthquakes. These changes will introduce safety hazards, which can be addressed via bridge disaster prevention and mitigation. Because near-fault pulse-like ground motions (NFPLGMs) have high peak accelerations, these motions can easily cause damage to a bridge. Therefore, in this study, a seismic fragility assessment is performed for long-unit PCCGBCSWs subjected to NFPLGMs considering spatial variability effects, and a sensitivity evaluation of the seismic fragility is conducted considering girder type, bearing type, ground motion type, and apparent wave velocity to offer a point of reference for seismic design. The results show that PCCGBCSWs are less vulnerable than concrete bridges. The shock absorption effect of the friction pendulum bearing is better than that of the viscous damper. The impact of NFPLGMs on bridges is greater than that of near-fault non-pulse-like ground motions (NFNPLMs) and far-fault ground motions (FFGMs). The seismic fragility under nonuniform excitation conditions is greater than that under uniform excitation conditions, showing an increasing trend with decreasing apparent wave velocity.

The Bridge Through the College (Part-1): Conception and Construction of Reinforced Concrete Bridge Across College Campus

“The bridge through the college” highlights how contracts and agreements signed many decades ago have to still be respected and fulfilled. A public highway planned to originally be laid on top of a filled-out irrigation canal passing through the campus of a college that commenced in 1977 was later replaced with a elevated bridge that has finally finished completion in 2023 and is now open to public. The bridge is designed as reinforced concrete girder bridge with concrete slab top poured composite with the girders. This article explains in detail the engineering, design and construction of a reinforced concrete girder bridge through the campus of Velagapudi Ramakrishna Siddhartha Engineering College in Vijayawada city of India. The challenges associated with design and construction are also discussed. Finally, the lessons learnt at the end of the completion of the bridge are enlisted and recommendations to improve efficiency of our design and construction methods are made. Keywords: Concrete, Bridge, Engineering, Construction, Pier, Girder, Reinforcement

Influence of modeling choices and prior information on the Bayesian assessment of a reinforced concrete bridge

AbstractA lot of bridges are aging and reaching the anticipated service life. To gain insight in their remaining resistance, inspections and measurements can be performed. The resulting information and data can be used to update variables in the degradation models of these bridges. To account for spatial variation, degradation variables can be modeled with random fields. The random fields of the degradation variables are updated based on a Bayesian inference procedure, where different types of heterogenous and indirect data are accounted for. Nevertheless, in this procedure, various assumptions need to be made, such as the quantification of measurement uncertainty, the structural and degradation model to be used, the prior distributions of the variables of interest, and so forth. These assumptions can influence the results of the Bayesian inference. Hence, in this work, it will be investigated what the influence is of different assumptions and how they affect the localization and quantification of damage. This will be done by application to a reinforced concrete girder bridge. The main conclusions are that the model used in the Bayesian inference procedure should resemble the actual structure as good as possible and that simplifications that are allowed in the design can lead to posterior distributions deviating a lot from the actual situation. Moreover, it is illustrated how information from visual observations can be included in the definition of the prior distributions and how this has a beneficial effect on the posterior predictions.

Project Spotlight: Tollway uses largest prestressed concrete bridge girders produced in Midwest

County Prestress & Precast LLC of Janesville, Wis., (formerly operating as County Materials Corp. at the time of this project) manufactured and delivered 523 prestressed concrete girders for the Mile-Long Bridge in Chicago, Ill.

Effectiveness of mortar injection repair activity on an existing prestressed bridge girder

This paper reports the results of an experimental test performed on a prestressed reinforced concrete bridge girder, extracted from an existing bridge of the Italian highway network. The element exhibited cracks damage along the curved tendons of the prestressing system, probably due to the rainwater infiltration into the protecting duct. The experiment consists of a three-point bending test, where a point vertical load is located at mid-span and cyclically increased until bending collapse occurs. Before the test, the cracks pattern has been repaired by high-pressure injection of high-resistance mortar. The test results demonstrate the effectiveness of the mortar injection repair intervention.

Effect of Cracks on the Influence Lines of a Smart Concrete Girder Bridge Based on the Element Size–Independent FE Model

A smart concrete girder bridge usually has various sensors, based on which several physical properties can be measured, and hence, the health condition can be evaluated. Cracks are always observed on a smart concrete girder bridge. In particular, some of the cracks are induced by overloaded vehicles, which is dangerous to its safe operation. However, due to the crack opening and closing effect, it exhibits nonlinear responses, posing challenges for accurately assessing its health condition. Influence lines (ILs) are a promising indicator for bridge damage. However, there is limited research on the effect of cracks on the ILs of a smart concrete girder bridge. A digital twin is commonly used to accompany the smart sensing system to accurately evaluate the health condition, where the finite element (FE) model is of great importance. Therefore, this study proposes an element size–independent FE model construction method based on the concrete damage plasticity (CDP) model to investigate the changes of displacement and strain ILs of different types of smart concrete girder bridges with bending cracks, which is helpful to guide how to use the ILs to identify the cracks and evaluate the health condition. Initially, a concrete constitutive model based on crushing/fracture energy is proposed, and the evolution law of tensile damage based on fracture energy is derived to construct the element size–independent FE model. Subsequently, experiments on a reinforced concrete (RC) simply supported beam and a prestressed concrete (PC) simply supported bridge subjected to bending failure are used to verify the FE models constructed by the proposed method. Finally, the FE models of a smart RC T‐beam bridge and a smart three‐span PC continuous bridge are established to study the changes in ILs caused by bending cracks. The change of displacement IL at the midspan due to cracks for the smart RC bridge exceeds 10% when the reinforcements yield, while it is less than 10% for the smart PC bridge even if the bridge is in the failure state. The change of both displacement and strain ILs becomes greater when the measurement point approaches the cracks, and the change of strain IL is only detectable when the measurement is close to the cracks. Due to the crack opening and closing effect, the displacement and strain ILs of a smart concrete girder bridge with bending cracks are inconsistent when different loads are applied. The findings can also be used as a pre‐IL‐based crack detection using the passing inspection vehicle‐induced dynamic response on a selection of type of ILs, determination of layout of sensors, and mass of inspection vehicle.

A preliminary investigation on material properties of existing prestressed concrete beams

This paper reports some preliminary results of an ongoing research activity addressed to collect and to elaborate the main mechanical properties of materials of pre- and post-tensioned concrete girder bridges. In particular, in this work data samples is obtained by analyzing design documents of a stock of existing bridges realized in Basilicata (south of Italy). At first, the paper presents a proposal on how information available is collected. Then, results of the statistical elaborations on the samples gathered are shown, in order to provide useful support in estimating the mechanical properties of the materials used in the bridges typologies considered in this study.

The Risk of Failure Assessment in Bina Marga Standard Designed Prestressed Concrete Girder Bridges under B-WIM Load Measurement

The use of precast prestressed concrete girder bridges in Indonesia has been increasing rapidly due to their high quality, reliability, and faster construction on site. The girder components are typically designed for a specific bridge span and can be prefabricated. The Directorate General of Highways of the Ministry of PUPR (Bina Marga) has released a standard design for prestressed concrete girder bridges with a typical span of up to 40 m. This design is based on the bridge loading standard SNI 1725 2016, which determines the live traffic load through consensus due to limited data on actual traffic load measurement results. However, the Ministry of PUPR has been implementing actual traffic load measurements using weigh-in-motion (WIM) technology to directly measure the load of passing vehicles. In this study, a risk assessment of the failure risk of a standard Bina Marga bridge with a 40-m span prestressed concrete girder type was conducted based on B-WIM load measurements. The results of this assessment indicate that the standard Bina Marga bridge has a failure risk of 1.48 x 10-4, which is smaller than the acceptable risk of failure according to the AASHTO LRFD Bridge Design Specification as referenced in SNI 1725 2016.

Bayesian-optimized interpretable surrogate model for seismic demand prediction of urban highway bridges

Urban highway bridges are crucial for regional economic development and population mobility, but they are vulnerable to seismic hazards. Accurately predicting the seismic demands of bridges is essential. Several commonly-used methods for seismic demand estimates, such as cloud analysis, incremental dynamic analysis, and multiple stripe analysis, are computationally expensive and subject to theoretical assumptions and convergence issues, especially for portfolios of bridges. Machine learning techniques can be effective, but their lack of interpretability hinders understanding of the surrogate model's predictions. To address these challenges, this study develops a Bayesian-optimized interpretable ensemble learning surrogate model for predicting and interpreting the critical seismic demands of urban highway bridges.Thousands of continuous prestressed concrete girder bridges with typical geometric configurations in China are generated, and 120 ground motion records with different frequency, waveform, and duration characteristics are chosen. The seismic demand dataset is established based on nonlinear time-history analyses for urban highway bridges, accounting for different types of uncertainties. The surrogate models are developed based on the XGBoost ensemble learning method, with hyperparameters automatically and efficiently determined by Bayesian optimization technique. Compared to the random search and grid search methods, Bayesian optimization is approximately 8 times and 29 times faster, respectively, and it also achieves the highest prediction accuracy. Meanwhile, the relationship of each hyperparameter in the surrogate model is also revealed. The prediction results of the proposed model are compared with other machine learning models. The SHAP algorithm is subsequently used to explain the model predictions regarding the feature importance, global interpretations, and feature dependency analysis. The study quantifies the contribution of each structural feature and seismic intensity measure to the selected critical seismic demand and identifies the interaction effects between different input variables in the prediction.

Cracking simulation and analysis of the mortise-and-tenon wet joints in Precast reinforced concrete ribbed girder Bridges

ABSTRACT Flexural tests were conducted on the normal section of two different forms of specimens with wet joints to study the damage and cracks of mortise-and-tenon wet joints. Simulations were performed to analyze the mortise-and-tenon joint specimens. The extent of damage and development of cracks of specimens with straight joints and mortise-and-tenon joints are similar. The interface cracking of the specimens with mortise-and-tenon joints is often caused by concrete cracking at the root. Different tenon sizes have a negligible effect on the cracking load and overall bearing capacity of specimens. Therefore, the tenon end and depth sizes are considered 25–37.5% of the joint width, and the transition zone of the joint interface is selected to be 100–150 mm. According to the calculation formula of the flexural bearing capacity at the wet joint position and reduction factor of straight joints φ f , the correction coefficient of mortise-and-tenon joints φ s was proposed to be 1.03.

Finite Element Analysis of Chloride Ingress in Prestressed Concrete Bridge Girders Accounting for Service-Life Ambient Conditions

Finite Element Analysis of Chloride Ingress in Prestressed Concrete Bridge Girders Accounting for Service-Life Ambient Conditions

Seismic Response of a PC Continuous Box Girder Bridge under Extreme Ambient Temperature

To study the effect of temperature on the seismic performance of a prestressed reinforced concrete (PC) continuous girder bridge with laminated rubber bearings (LRBs), a two-linked continuous bridge was used as the background to consider the effect of extreme temperature on the properties of LRBs and pier concrete. First, the properties of concrete specimens were tested at different temperatures to obtain their mechanical parameters at extreme temperatures. Then, we obtained the effect of extreme temperature on the seismic response of consecutive bridges with LRBs by examining the seismic response of the pier moments, pier top displacements, and bearing deformations. The results show that compared with normal temperatures, the extreme temperature causes a change in parameters of the LRBs and concrete pier, which increases the internal force and displacement response of a pier under an extremely low temperature by 37.13% and 32.74%, respectively. The displacement of bearings under extremely high temperature conditions increases by 16.31%. The influence of temperature changes on the mechanical parameters of LRBs will change the connection stiffness of the pier and superstructure, resulting in significant changes in the seismic response of the pier and bearing, so that the internal force and displacement response of the pier are negatively correlated with the temperature.

A Case Study Based Analysis for the Behaviour and Optimum Design of Steel Concrete Composite Bridge Girders

A Case Study Based Analysis for the Behaviour and Optimum Design of Steel Concrete Composite Bridge Girders

Repair and Retrofitting of Concrete Bridge Girder Using Epoxy, Micro Mortar, and CFRP Sheets

AbstractBangladesh is connected through bridges and many of them are experiencing damages due to the aging of concrete, weathering effect, or excessive loading. Repair and retrofitting of those bridges are becoming inevitable to make them operational. In this study, the damages of a concrete bridge have been investigated through non‐destructive tests and numerical methods. A repair and retrofitting strategy for the damaged girders has been developed using epoxy injection, shrinkage‐compensated micro mortar, and externally bonded Carbon Fiber Reinforced Polymer (CFRP) sheets. The micro mortars are injected inside the large cracks and damaged portions of the girders. The flexural zones of the girders were strengthened using U‐shaped CFRP sheets. Field load tests are also conducted to determine the achieved improvement from the repair strengthening work. Dynamic accelerometers, digital probes, and linear variable differential transformers (LVDT) were attached to determine the actual deflections of the girder before and under loading. Finite Element models (FEM) are developed to validate the field data and determine the shear and flexural resistance of the retrofitted girders. The outcomes show that the retrofitted bridge satisfies the design requirements of the AASHTO‐LRFD guidelines.