Composite Bridge Deck Research Articles

Fatigue behavior of short-headed studs embedded in Ultra-high Toughness Cementitious Composites (UHTCC)

The multi-cracking and strain-hardening capacities of Ultra-high Toughness Cementitious Composites (UHTCC) make it feasible for orthotropic steel bridge decks (OSBDs) applications to control crack width. In this composite bridge deck, shear connectors play an important role in providing good shear strength and ensuring structural service performance. To evaluate the shear resistance of short-headed studs embedded in ultra-thin UHTCC layer, three series of push-out tests were conducted in this study. The test results including shear strength, fatigue strength, failure modes, dynamic slip, stiffness degradation, plastic slip and residual mechanical properties were all considered and carefully discussed. In this study, the shear force of shear connectors was calculated and compared with current codes. The stress amplitude-fatigue life (S-N) relationship of studs was fitted by different codes. Then the empirical formulation was developed to predict the load-slip behavior and stiffness degradation of studs during fatigue loading. The relationship between plastic slip and fatigue life was established and normalized. Furthermore, based on post-fatigue static test results and test results in previous research, a new machine learning model was proposed to predict the residual shear strength of studs and contrasted with previous model. Then Analysis of Variance (ANOVA) with two parameters (i.e. load amplitude, maximum repeated force) was conducted and revealed that the peak load significantly impacted the residual shear strength of push-out specimens compared with load amplitude. Moreover, a parametric study was conducted to further investigate the degradation of studs under various working conditions. By experimental and theoretical analysis, UHTCC could fully develop the shear strength of studs embedded in ultra-thin cover thickness. And related models were established to predict the static and fatigue behavior of steel-UHTCC push-out specimen.

Experimental investigation on UHPC shrinkage of full-scale steel-UHPC composite bridge deck

Three full-scale composite bridge deck segments with various steel-to-UHPC area ratios, as well as free shrinkage specimens, were tested to investigate the restrained shrinkage and cracking behaviors. Based on the measured UHPC strain and temperature, the variations in shrinkage strain were analyzed, and a time-varying analysis theory for calculating elastic modulus and shrinkage stress during UHPC curing process was proposed. The results revealed that UHPC free shrinkage strain (after 30 days) was within 700–750 με. The variation trend in UHPC elastic modulus and shrinkage stress were basically consistent the development of shrinkage strain. The shrinkage tensile stress at UHPC upper surface was approximately 2 MPa, equaling to the difference between cracking stress and axial tensile strength. Based on the free and restrained strains, a time-dependent equivalent stress method was found to be effective for calculating UHPC elastic modulus and shrinkage stress in the composite deck.

Flexural behavior of novel profiled steel-UHTCC assembled composite bridge decks

Ultra-high toughness cementitious composite (UHTCC) has been noticed in the application of composite bridge deck (CBD) structures to avoid tensile cracks, benefiting from its excellent crack resistance behavior and characteristic of tensile strain hardening. In this study, a novel profiled steel-UHTCC assembled CBDs was proposed by adopting duplicate profiled steel parts that integrated the Perfobond rib (PBL) shear connector onto their top flange plates, which will improve fabrication convenience and economic efficiency. The flexural behavior of the assembled CBDs was investigated. Four specimens assembled respectively with T-shaped, Z-shaped, B-shaped, and H-shaped profiled steel parts were designed and fabricated. The failure modes, load-deflection curves, strain distributions, and slippage situations of four specimens were monitored and discussed. Then, the theoretical analyses on the shear connection degrees and ultimate flexural capacities of the assembled CBDs were performed, and a theoretical formula was proposed for calculating the ultimate flexural capacity. Finite element (FE) models of the assembled CBDs were established via ABAQUS software and validated against the test results. Ten groups of FE examples were designed for the detailed study of several key design parameters including shear span length, PBL hole diameter, thickness of UHTCC slab, thickness of steel web, and normalized PBL hole numbers. Finally, the proposed theoretical formula was validated using experimental and simulated results, demonstrating the validity of the proposed formula.

Fatigue analysis of orthotropic steel-ultra-high-performance fiber-reinforced concrete (UHPFRC) composite deck considering accelerated deterioration and self-healing of fractured ultra-high-performance fiber-reinforced concrete in surface water condition

In this study, an orthotropic steel bridge deck overlaid with ultra-high-performance fiber-reinforced concrete (UHPFRC) is investigated using the finite element analysis. The composite bridge deck which is undergone moving-wheel load is examined under environmental surface water conditions. Two phases, i.e., Phases 1 and 2, are considered for the material model of the UHPFRC with stagnant water. In Phase 1, mechanical recoveries of the tensile strength and reloading stiffness are considered for the cracked UHPFRC caused by the autogenous self-healing behavior. In Phase 2, under the moving-wheel load, the crack bridging stress degradation in reinforced overlayer accelerates due to the closing–opening actions of surface cracks in water. In both phases, the deformation behaviors of the steel deck plate and UHPFRC overlayer are numerically examined. The results of the current numerical model agree with the experimental data in terms of the strain tendency, wherein the strain range of the steel deck plate and UHPFRC overlayer decreases in Phase 1 and progressively increases in Phase 2. Therefore, it can be asserted that, under the surface water condition, scenarios considering two phases of the material model of cracked UHPFRC, have governed the strain behaviors of the tested composite bridge deck.

Tensile Fatigue Properties of Ordinary Plain Concrete and Reinforced Concrete under Flexural Loading.

Many bridge structural components are subjected to repetitive vehicle load and temperature gradient action. The resulting cyclic tensile stresses within the structures could cause premature fatigue failure of concrete, dramatically impairing structural components' durability and sustainability. Although substantial knowledge of fatigue properties on low-strength pavement concrete and high-strength structural concrete has been obtained, research on the most widely used normal-grade ordinary concrete in bridge engineering is still ongoing. Therefore, a four-point bending fatigue test of 97 C50 concrete specimens under a constant amplitude sinusoidal wave was conducted in the laboratory, the flexural fatigue behavior of plain and reinforced concrete specimens was studied, and the cyclic deformation evolution of concrete under fatigue loading was obtained. The empirical fatigue S-N equations of concrete with a failure probability p of 0.1~0.5 were derived through statistical analysis of the test results. The fatigue life of the tested specimens exhibited a two-parameter Weibull distribution. In addition to the maximum stress level Smax, the stress ratio R is also a key factor affecting the flexural fatigue life of concrete N. The semi-logarithmic and logarithmic equations were almost identical at the tested stress levels, the latter predicting longer fatigue life for Smax < 0.70. The restraining effect from steel reinforcement slightly lengthened the concrete's fatigue cracking initiation life. The insight into concrete flexural fatigue properties from this study not only contributes to a better understanding of structural concrete, but also provides a basis for the practical evaluation of concrete or composite bridge decks.

Investigation on permanent deformation in steel-concrete composite beam bridge deck pavement under temperature-load coupling effect

Rutting is one of the common distresses observed in asphalt pavement, influenced by temperature and load conditions. To clarify the permanent deformation behavior of steel-concrete composite beam (SCCB) bridge deck pavement under temperature-load coupling effect and provide references for the distress cause analysis, five typical SCCB bridge deck pavements were selected. The temperature distribution and the temperature stress of the pavement structures were analyzed by numerical simulation under periodic temperature variations. In addition, considering the daily variation in traffic volume, the permanent deformation of the five pavement structures were calculated under temperature-load coupling effect. Finally, the influence of heavy load on the development of rutting distress was also investigated. The results show that the temperature field and temperature stresses within the SCCB bridge deck pavement exhibit periodic variations under periodic temperature variations. Additionally, after 500,000 times of standard axle load application, “EA + SMA” exhibits the smallest permanent deformation and the best resistance to rutting distress under temperature-load coupling effect. Finally, heavy load conditions have a great influence on the permanent deformation of SCCB bridge deck pavement. In areas with severe rutting distresses, it is recommended to use “EA + SMA” pavement structure in SCCB bridge.

Study on Shear Resistance and Structural Performance of Corrugated Steel–Concrete Composite Deck

This study looks into a new composite bridge deck structure that employs a corrugated steel plate as the base. The goal is to address the shortcomings of traditional deck-bearing capacity, stiffness, and stress performance. Specifically, this study investigates the shear performance and slip characteristics of this structure. To achieve this, the study analyzes the shear behavior and slip tendencies of the composite bridge deck. The study focuses on the role of shear studs and PBL (Perfobond Leiste) perforated steel plates as essential components for shear connections. The shear performance of the composite deck is analyzed based on the structure of shear connection keys such as shear studs and PBL perforated steel plates. The advantages of composite decks in terms of stiffness, self-weight, load-bearing capacity, shear resistance, slip resistance, etc., are discussed to provide a theoretical reference for practical engineering applications. The shear resistance of shear stud shear keys is investigated through shear push-out experiments, and the shear resistance of shear studs is investigated through finite element simulations based on the ABAQUS 2020 finite element software. The results showed that the shear load capacity of the shear studs increased with the increase in the height-to-diameter ratio for different diameters of the shear studs, and the range of increases was from 2% to 23%. However, when the diameter of the shear stud exceeded 22 mm, the ultimate shear capacity of the shear stud increased with the increase in the height-to-diameter ratio, and the magnitude of the increase slowed down. For the actual design of the composite deck, it is recommended to maintain a shear stud height-to-diameter ratio within the range of 9 to 12. When using a composite deck with a PBL open-hole steel plate, the maximum longitudinal slip at the plate end and within the span is only 0.28 mm and 0.0158 mm, respectively. These values are 31% and 36% lower than those of the composite deck with a peg shear key. Additionally, the vertical peeling within the span of the PBL open-hole steel plate is merely 0.46 mm, showing a 21% reduction compared to that of the shear studs. It can be seen that the PBL perforated steel plates are more effective than the shear studs in resisting slip and peel.

Mode I and Mode II fracture behavior in pultruded glass fiber-polymer – Experimental and numerical investigation

Many recent works have shown that the capacity of pultruded glass fiber-polymer structural members is governed by interlaminar failure. However, there is still a lack of information regarding the fracture properties associated and the best techniques to be adopted. This paper aims to propose a testing methodology and to evaluate the interlaminar fracture of pultruded glass fiber-polymer specimens extracted from a composite bridge deck system. Both Modes I and II were investigated, through Double Cantilever Beam (DCB) and End-Loaded-Split (ELS) tests, respectively. The starter crack (or initial separation) was introduced via a water jet machine and the crack length was measured with the video extensometer technique. In all, nine different methods were applied to obtain the fracture toughness properties. The results are discussed and compared with 2D non-linear finite element models, where the cohesive zone model (CZM) approach was used. The Modified Beam Theory method (MBTASTM) presented the best results for crack propagation in Mode I, whereas differences lower than 1% from experiments were obtained when using the Corrected beam theory using effective crack length (CBTE) and the Experimental compliance method (EMC) methods for Mode II.

Design and Optimization of the Bi-Directional U-Ribbed Stiffening Plate–Concrete Composite Bridge Deck Structure

The steel–concrete composite structure is widely used in civil engineering for large-span bridges. Orthotropic steel bridge decks (OSDs) have particularly gained popularity due to their excellent mechanical performance. To address cracking issues in OSDs and concrete in negative moment regions, a novel bi-directional U-ribbed stiffening plate (BUSP)–concrete composite bridge deck is proposed. By using finite element analysis, the mechanical performance is evaluated based on maximum tensile stress and vertical displacement of concrete overlays. Results show that the BUSP–concrete deck outperformed conventional flat decks. It is also found that increasing the height, thickness, and opening width of U-ribs reduced tensile stress and maximum displacement. Adjusting height had the most significant effect on displacement while opening width affected tensile stress the most. Considering material usage, optimizing height is proved to be more effective than adjusting thickness and opening width. Decreasing spacing parameters improved performance but added complexity and reduced construction convenience. These findings will guide the design and optimization of steel–concrete composite bridge deck structures.

Fuzhou–Xiamen high-speed railway: a new paradigm for China’s cross-sea railways

The new 277 km Fuzhou–Xiamen high-speed railway in China is the country’s first cross-sea railway designed for operational speeds of 350 km/h. Completed in 2023, it involved various advanced construction technologies, including the world’s first 1000 t bridge-building machine to be used offshore, advanced corrosion-resistant steel, pioneering rotation of a main bridge pylon, and aerodynamic steel–concrete composite bridge decks with ballastless tracks. The innovative project represents a milestone for China’s high-speed railway, heralding a new era of cross-sea transportation.

Experimental Investigation on Fatigue Improvement of Orthotropic Steel Bridge Deck Using Steel Fiber Reinforced Concrete

AbstractThe high-performance topping concrete overlay would significantly reduce the fatigue stresses at susceptible details of orthotropic steel deck (OSD) and effectively improve the fatigue performance. Full-scale fatigue tests and numerical simulations were carried out to quantify the effects of steel fiber reinforced concrete (SFRC) topping pavement in reducing the OSD fatigue stresses based on a practical bridge design. Fatigue stress of the OSD critical details was measured from tests and cracking was observed in the SFRC overlay. Both an innovative pre-pump-pulse Brillouin optical time domain analysis (PPP-BOTDA) distributed optical fiber sensor and strain gauges were also used to measure the stress at OSD fatigue-prone details, including the crossbeam cut-out, rib-to-deck weld, rib-to-crossbeam weld and splice of U-rib. The corresponding three-dimensional (3-D) finite element model was then established and verified by the test results, and used to conduct a parametric study to obtain a quantitative expression of fatigue stress reduction factor, in terms of relative elastic modulus and thickness of overlay and steel deck plate. The proposed quantitative model of the fatigue stress reduction effect can guide the cost-effective design of composite bridge deck.

Experimental and Numerical Study of Transversal Flexural Behavior on Steel Ultrahigh-Toughness Cementitious Composite Bridge Decks

Experimental and Numerical Study of Transversal Flexural Behavior on Steel Ultrahigh-Toughness Cementitious Composite Bridge Decks

Mechanical behavior of natural bonding interface in hollow steel-UHPC composite bridge deck

The hollow steel-UHPC (Ultra-high performance concrete) composite deck with interfacial connection by natural bond is a new type of deck with simple appearance and high-stress efficiency. However, the interfacial bonding properties of this composite deck and their effect on the structural performance remain unclear. In this study, the shear tests under different interface sizes, curing conditions and interface states were carried out to analyze the interfacial bonding properties between UHPC and steel tube in composite deck. Besides, the finite element model was used to further study the influence of different interface behaviors on the mechanical properties of composite deck. Results indicated that the whole failure process of UHPC-steel tube composite specimens included the elastic stage, the interface bond failure stage and the friction stage. The ultimate strength of composite specimens would not completely be lost when they failed, since there was also residual interface strength provided by friction. The influence of curing conditions on the interface strength was most significant. The ultimate load of composite deck was increased by 13.69% when the interfacial bonding strength was increased from 0.5 to 4 MPa. However, the influence of interfacial stiffness on the mechanical behavior of composite deck was negligible. When the interfacial fracture energy was increased from 1.4 to 4 N/mm, the ultimate load of composite deck was increased nonlinearly and slowly by 13.87%. Finally, there was little effect on the performance of composite deck when the interfacial bonding strength exceeded 4 MPa or the fracture energy was larger than 4 N/mm.

A Damage Detection Approach in the Era of Industry 4.0 Using the Relationship between Circular Economy, Data Mining, and Artificial Intelligence

Over the last decades, the emergence of new technologies has inspired a paradigm shift for the fourth industrial revolution. For example, circular economy, data mining, and artificial intelligence (AI), which are multidisciplinary topics, have recently attracted industrial and academic interests. Sustainable structural health monitoring (SHM) also concerns the continuous structural assessment of civil, mechanical, aerospace, and industrial structures to upgrade conventional SHM systems. A damage detection approach inspired by the principles of data mining with the adoption of circular-economic thinking is proposed in this study. In addition, vibration characteristics of a composite bridge deck structure are employed as inputs of AI algorithms. Likewise, an artificial neural network (ANN) integrated with a genetic algorithm (GA) was also developed for detecting the damage. GA was applied to define the initial weights of the neural network. To aid the aim, a range of damage scenarios was generated and the achieved outcomes confirm the feasibility of the developed method in the fault diagnosis procedure. Several data mining techniques were also employed to compare the performance of the developed model. It is concluded that the ANN integrated with GA presents a relatively fitting capacity in the detection of damage severity.

Experimental investigation on mechanical behavior of T-type perfobond rid shear connectors under combined shear and tension

The stress of shear connectors becomes more complicated as the span length of steel-concrete composite bridges increases. To bear the great shear and uplift forces, a T-type perfobond rib (T-type PBL) shear connector with sufficient stiffness and ductility is proposed. While the shear behavior of T-type PBL connectors has been evaluated in previous studies, its mechanical performance under combined shear and tension is not well understood due to the particular shape and numerous impact factors. Therefore, one pull-out test considering pure tension and seven modified push-out tests considering combined shear and tension were carried out to investigate the failure mode, bearing capacity, and load-slip behavior of T-type PBL connectors under combined actions. The pull-out test was performed to determine the tensile resistance, followed by a series of modified push-out tests with constant horizontal tension to investigate the structural behaviors. Additionally, the effects of the rib height, flange width, and hole numbers were evaluated. Based on the test results, conical failure surfaces formed from the flange of the T-type PBL to the concrete surface for all specimens, and the concrete failure angle was approximately 32°. The bearing capacity of the specimen improved by 26% when the perfobond rib height increased from 100 mm to 120 mm, but the flange width barely had any effect. The capacity of 1-hole specimen dropped by 20% while 2-hole specimen increased by 8% compared to the standard specimen, which may relate to the distance between adjacent holes. Increasing the rib height by 25% and 50% reduced the initial relative slip (S90) by 30% and 32%, respectively, indicating the improvement in initial stiffness. Generally, the pull-out resistance of the T-type PBL shear connector was enhanced by increasing the flange width, rib height, and number of holes. An evaluation equation considering the hole number and hole spacing was suggested for the bearing capacity of T-type PBL shear connectors under the combined actions. The validity was verified by test results, with a calculated-to-test-result ratio of 1.12 and standard deviation of 0.15. This study could enhance the understanding of the behavior of T-type PBL connectors under the combined actions, and promote the potential application in long-span composite bridge decks.

Shrinkage and cracking sensibility of steel-alkali activated UHPC composite bridge decks

Alkali-activated ultra-high performance concrete (AAUHPC) is a concrete containing excellent properties such as high strength, high durability and low carbon emission. In this study, tests were carried out to investigate the basic mechanical properties of AAUHPC and restrained shrinkage behavior of steel-AAUHPC composite bridge decks. The effects of different parameters (e.g. the stiffness of steel deck, the thickness of AAUHPC layer, arrangement of studs and the temperature and humidity) on the early age contraction and cracking sensitivity of steel-AAUHPC composite bridge decks were investigated. The results showed that the AAUHPC deck without any internal or external restraint showed a higher shrinkage at a faster rate in the early stage. The rate of shrinkage in the later stage declined gradually with age, and the overall shrinkage deformation was found to be stable at the age of 28 days. For the reinforced AAUHPC composite decks subjected to internal and external constraints, the restrained effect of steel deck, studs and steel reinforcement on the shrinkage of AAUHPC was quite prominent which increased with the increase of steel deck stiffness and the thickness of AAUHPC, where as the temperature and humidity of environment showed a minor effect on the restrained shrinkage deformation at 28 days. The tensile properties and toughness of AAUHPC with steel fibers were found to be high. During the entire test, no cracks were observed on the surface of the reinforced AAUHPC composite bridge decks. However, the cracking risk of AAUHPC was high in the first 2 days, and the cracking risk coefficient in the later stage was about 0.2. In addition, the accuracy of the experimental results was verified by finite element analysis.

Flexural Performance and Design of Steel-UHTCC Composite Bridge Decks with Different Composite Degrees under Hogging Moments

Due to the excellent tensile properties and long-term durability, using ultrahigh-toughness cementitious composite (UHTCC) at the hogging moment regions of long-span composite bridge decks is a new solution to the cracking issue. Composite degrees and the longitudinal reinforcement ratio have been suspected of influencing the flexural performance of steel-UHTCC composite bridge decks under hogging moments, but the extent of the influence remains unclear. This study aims to investigate the influence of these two core design parameters. Six specimens with different stud spacings and longitudinal reinforcement ratios were designed to investigate the failure modes, flexural capacity, deformation behavior, and cracking characteristics. The results show that the cracking stresses σ0.05 and σ0.1 in the steel-UHTCC composite bridge decks were 58.6%–216.8% and 58.9%–213.5% higher than those in the steel-normal-strength concrete (NSC) composite bridge decks. As the longitudinal reinforcement spacing reduced from 125 to 75 mm, the growth of the crack width was effectively restrained, and the cracking stresses σ0.05 and σ0.1 increased by 36.6% and 71.2%, respectively. Finally, a modified theoretical model is established to evaluate the influence of composite degrees on the elastic flexural performance of steel-UHTCC composite bridge decks. The dimensionless composite degree η is defined as a core parameter in this model. For practical elastic design, the threshold value of the dimensionless composite degree can be determined as 0.005.

An Experimental Study on Negative Bending Behavior of Composite Bridge Decks with Steel-Fiber-Reinforced Concrete and Longitudinal Bulb-Flat Ribs

An Experimental Study on Negative Bending Behavior of Composite Bridge Decks with Steel-Fiber-Reinforced Concrete and Longitudinal Bulb-Flat Ribs

An Experimental Study on the Flexural Performance of a Steel-ECC Composite Bridge Deck Sheet in the Negative Moment Zone

This paper seeks to solve the problem of orthotropic anisotropic steel deck pavement being prone to damage and fatigue, and to study the negative moment performance of steel-ECC concrete composite deck slabs. In this work, four groups of eight specimens were designed for the negative moment four-point bending test study, which included four variables of two ECC slab thicknesses and two bolt spacings. By analyzing the damage mode, crack distribution characteristics, bending load capacity, load-deflection curve, and load-strain curve, the effects of different ECC slab thicknesses and bolt spacings on the bending performance, deformation capacity, and cracking behavior of the steel-ECC composite bridge deck were investigated. The test showed that the combined structure of the ECC and steel plate showed good integrity and good ductility under a negative bending moment, and the damage mode of the member was pure bending of a section of the ECC with concrete cracking damage. When the thickness of the ECC plate increased from 50 mm to 75 mm, the ultimate flexural load capacity of the specimen increased by 92.6%, and when the distance between bolts was reduced from 200 mm to 150 mm, the ultimate flexural load capacity of the specimen increased by 13.4%. The increase in the ECC layer thickness increases the ultimate bearing capacity of the specimen significantly, and the decrease in the bolt spacing increases the ultimate bearing capacity of the specimen less.

A Symplectic-Spectral Element Method for High Frequency Vibration Analysis and Its Application in Structure-Borne Noise Prediction

The frequency-domain vibration model of the vehicle-track structure is established based on the symplectic-spectral element method (S-SEM). To this end, the vehicle is considered as 10-degree-of-freedom, and the rail is modeled by an infinite Timoshenko beam supported by discrete sprung fasteners. Further, the track slab and base plate are regarded as two-dimensional Timoshenko beams supported by uniformly distributed sprung elements. Using the pseudo excitation method (PEM), the track irregularity is viewed as the pseudo load. The vibration response and the internal force of the single-layer or multi-layer beam models are obtained by solving the corresponding S-SEM-based equations. The spectral forces are also applied in frequency bands to the finite element (FE) and statistical energy analysis (SEA) acoustic models. The steel-concrete composite bridge deck is simulated with composite plate materials. The effectiveness of the proposed method is verified by comparing the predicted results with those obtained from the field test. The achieved results reveal that multi-layer beam structures effectively consume energy, and elastic fasteners and steel springs are capable of effectively reducing bridge noise.