Concrete Composite Deck Research Articles

Structural Design and Mechanical Behavior Investigation of Steel–Concrete Composite Decks of Narrow-Width Steel Box Composite Bridge

Steel–concrete composite decks are commonly employed in narrow-width steel box composite girder bridges to augment their lateral spanning capabilities, while the concurrent omission of longitudinal stiffeners leads to a substantial reduction in the number of components, thereby yielding a structurally optimized bridge configuration. This paper delineates the structural design parameters of a narrow-profile steel box composite girder bridge and assess the mechanical behavior of its incorporated steel–concrete composite deck under static and fatigue loading conditions. To this end, two full-scale segment specimens from the composite bridge decks were subjected to equal amplitude cyclic fatigue tests. The investigation specifically concentrated on the impacts of two types of shear connectors—namely, perforated steel plates combined with shear studs and perfobond rib shear connectors (PBL connectors)—on the static and fatigue performance, including fatigue stiffness, of the steel–concrete composite bridge decks. The results indicate that, under the static bending condition, the composite deck specimen equipped with stud connectors demonstrates superior overall flexural stiffness in comparison to the specimen featuring PBL connectors. Furthermore, the flexural stiffness of the steel–concrete composite specimens experiences a negligible alteration across two million fatigue loading cycles. Upon the completion of two million fatigue loading cycles, the composite deck specimens incorporating the shear connectors composed of perforated steel plates and shear studs exhibit relatively wider crack widths under the static peak load. Both configurations of the steel–concrete composite bridge deck specimens manifest evident interfacial detachment, signifying insufficient tensile pull-out stiffness of the shear connectors. It is recommended to increase the quantity of the shear connectors or select the pertinent types in order to enhance the interface shear resistance.

Flexural performance of a prefabricated steel–UHPC composite deck under transverse hogging moment

This paper aims to investigate the flexural performance of a prefabricated steel–ultra-high-performance concrete (UHPC) composite deck (PSUCD) consisting of an orthotropic steel deck (OSD) and a reinforced UHPC layer under transverse hogging moment. Ten full-scale steel–UHPC composite slab specimens were subjected to four-point flexural tests, which varied shear connectors, steel reinforcement, and wet joint interfaces. The results showed that all specimens exhibited typical flexural failure with excessive opening of critical cracks in the UHPC layer. The specimens utilizing notched perfobond strip connectors (NPBLs) with perforating rebars had higher nominal cracking strength (maximum crack width of 0.05 mm) and ultimate capacity by 15% and 27%, respectively, compared to those using studs. The perforating rebars in NPBLs improved post-cracking performance, increasing nominal cracking strength and ultimate capacity by 14% and 16%, respectively. The lateral interfaces of rectangular-tooth-shaped wet joints resulted in a local weak link in PSUCDs, leading to a 17% decrease in nominal cracking strength, and as much as 26% if interfacial roughening was omitted. Increasing the diameter of surficial reinforcement from 10 mm to 12 mm improved nominal cracking strength and ultimate capacity by 20% and 17%, respectively. Considering the influence of wet joint interfaces, prediction models for maximum crack width, nominal cracking strength, and ultimate capacity were developed and validated for the performance design of PSUCDs under transverse hogging moment.

Performance of recycled aggregate concrete composite metal decks under elevated temperatures: a comprehensive review

ABSTRACT This comprehensive review explores the performance of composite metal decks and structural elements incorporating recycled aggregate concrete (RAC) at elevated temperatures. Despite the acknowledged environmental benefits of using recycled aggregates in concrete production, there is a notable gap in the literature regarding their behaviour under fire conditions. The investigation delves into studies encompassing fire resistance, physio-thermal properties, mechanical attributes, and structural performance of composite metal decks constructed with RAC. The analysis reveals that the inclusion of recycled aggregates has both positive and negative impacts on these elements when exposed to high temperatures. The fire resistance of metal decking composite slabs is significantly influenced by material properties, composition, and RAC mix design. Experimental findings indicate that RAC slabs showed larger midspan deflection under load and fire exposure compared to their counterpart NC slabs. After 120 min. of duration, the mid-span deflection of RAC-0 was recorded to be 19 % higher than the corresponding deflection of NC-0 slab. While temperature-time curves show comparable performance between RAC and natural concrete (NC) slabs, RAC slabs exhibit a notably lower ratio of soffit temperature to the upper surface temperature, resulting in increased spalling. In conclusion, this study advocates for the broader utilization of RAC in constructing structural elements, particularly composite slabs facing extreme temperatures. However, it emphasizes the need for additional research to optimize fire resistance and gain a comprehensive understanding of their behaviour. The findings provide essential guidance for structural engineers and researchers involved in the design of sustainable and fire-resistant structures.

Study on early shrinkage and cracking of slab in UHPC light-weight composite deck based on ambient temperature and humidity effects

This study investigates the early performance and potential issues of ultra-high-performance concrete (UHPC) light-weight composite decks (LCBDs) used in municipal highway bridge design. The major objective of this research was to understand the complex evolution of temperature and humidity within immature UHPC thin layers, which can lead to deformation and secondary stress, potentially causing cracks and threatening the long-term applicability and safety of steel-concrete composite bridges. Understanding of the mechanism of this process will be the basis for subsequent work. The early performance of UHPC with ordinary concrete is compared. Besides, discussions are conducted on the basic thermal conductivity theory of three-dimensional porous media and the hydration mechanism of cement-based materials that are appropriate for early-stage UHPC. Subsequently, a refined thermo-mechanical coupling analysis method for steel-UHPC LCBD was proposed, implemented using ABAQUS, and validated through a UHPC composite beam test. This method was applied to calculate the early shrinkage of the UHPC layer in a steel-UHPC LCBD and evaluate the risk of cracking in an actual bridge expansion project, providing a rationality evaluation of a bridge design and its construction procedure.

Numerical and experimental study of a segmentally prefabricated orthotropic steel–ultra-high-performance concrete composite deck for long-span cable-stayed bridges

Utilizing the high strengths, toughness, and durability of ultra-high-performance concrete (UHPC), a segmentally prefabricated orthotropic steel–UHPC composite deck (POSUCD) system has been developed for long-span cable-stayed bridges. The deck system combines an orthotropic steel deck (OSD) with a reinforced UHPC layer using notched perfobond strips (NPBLs). The UHPC layer is prefabricated onto the OSD of the girder segment in the factory to form the POSUCD. After the precast UHPC layer is cured, the girder segments are transported to the bridge site and assembled. The precast UHPC layers are then connected via transverse wet joints before tensioning stay cables. Against the background of the Danjiangkou Reservoir Bridge with a main span of 760 m, finite element (FE) analysis was conducted to examine the stress state and flexural tests were carried out on local full-scale models to verify the feasibility of POSUCD. The results show that the prefabricated UHPC layer reduces the maximum static compressive stress of the steel deck in the girder system by 21%, and the stress ranges at fatigue-prone details of the steel deck are decreased by 28%–90% compared to traditional OSDs with asphalt overlay. Since the prefabricated UHPC layer helps withstand dead axial load in the main girder, the high compressive strengths of UHPC can be utilized more effectively than in deck systems with UHPC only used as a cast-in-situ overlay to resist vehicular wheel loads. The transverse wet joint interfaces were identified as the weakest aspect of the POSUCD, whether under tension or compression; however, their nominal flexural strengths along the longitudinal direction meet the required design standards. The shear resistance of NPBLs was also well confirmed by the minimal interfacial slip on the specimen when it reached the ultimate capacity under positive bending moment.

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.

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.

Lateral trusses between I‐girders introducing torsional stiffness to a composite bridge in Guatemala

AbstractThe ways of designing and building steel girder bridges with a composite concrete deck vary much between different parts of the world. A bridge system with twin steel I‐girders or a concept with multiple (more than two) girders can be used. The design and use of details and secondary systems also vary a lot. In order to give horizontal stabilization and distribute horizontal loads, bracing between the I‐girders bracings are often used. Although not so common, the bracing can also be used to distribute vertical loads between the main girders. To describe and to analyze the possible impact from using a lateral bracing, this paper describes the design of a curved bridge in Guatemala City and its challenges. The new Bridge over the Pinula River is designed as a steel‐concrete composite bridge with multiple steel girders with a concrete deck on top and has lateral bracing between the girders. The bridge is used as a case study to analyze the impact from a lateral bracing system on the vertical load distribution between the longitudinal girders. The bridge was designed with lateral bracing between the top flanges along the whole bridge and with bracing between the lower flanges near the supports. The case study shows that the distribution of eccentric vertical loads between the longitudinal girders can be improved by using lateral bracing between the lower flanges for multiple girders. In some cases, it may not be beneficial to use lateral bracings along the whole bridge length, like for example this bridge. In this case due to the governing design cases in the construction stages where these bracings influenced the torsional stiffness of the bridge in such way that an unfavorable distribution of the support reactions between the six girders at some supports was achieved.

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.

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.

End diaphragm and interior cross frame modeling in steel tub girder superstructures

Composite steel tub girders are proven to be an economical choice for long span bridges. However, detailed analysis of such superstructures requires extensive Finite Element (FE) modeling that includes many internal and external diaphragms. This paper is an attempt to study diaphragms and interior cross frames in tub girders and present simplified FE modeling details for the tub girder superstructures under gravity and seismic loadings incorporating accurate end diaphragm and interior cross frame stiffness equations. The simplified model is applicable to design of new tub girder bridges as well as load rating, health monitoring and retrofitting of existing bridges which require more sophisticated models. To this end, first a parametric study using 18 different FE models was carried out to better understand the behavior of tub girder superstructure and its components such as end diaphragms, the composite concrete deck and interior cross frames. Second, the stiffness equations for the end diaphragms and interior cross frames were derived analytically. These were associated with equivalent beam elements, which were used in combination with girder/deck elements to arrive at the simplified model. The resultant FE modeling was validated against detailed 3D FE models under gravity and seismic loads as well as the fundamental modes of vibration. Results indicated that the modeling approach is able to efficiently simulate different component behaviors and estimate the static and dynamic demands on the girders with remarkable accuracy.

Study of a Layered Plate Girder Element of Composite Materials and Its Applications

This study aims to provide an effective method to study the behavior of a steel–concrete composite deck. First, the structural characteristics of the composite deck and the challenges arising in the computational analysis of the structure using general software are described. Then, an LPGE element that combines the plate element and the girder element into one element to conveniently construct the model with high computation efficiency is proposed. Based on the principle of multivariate field function, the constraint matrix for the plate and girder and the stiffness matrix for the LPGE are derived. The LPGE method is used to study the behavior of the composite deck through the computation of a steel truss arch bridge. The computation results are compared with the results obtained in ANSYS and the test results to verify the correctness and effectiveness of the LPGE method. The results of the paper offer references for the analysis of steel–concrete composite decks.

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 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.

Wind tunnel tests on the unsteady galloping of a bridge deck with open cross section in turbulent flow

Steel–concrete composite bridge decks may risk galloping instability during their bridge-launching phase, since the normally first launched steel boxes could feature bluff and lightweight cross section. In our previous study, a bridge deck of open cross section (typically used in steel–concrete composite bridges) has been found in smooth flow highly prone to the unsteady galloping instability occurring at relatively low reduced wind speed. Considering the natural wind field is usually turbulent, motivations arise to understand what role can the incident turbulence play in the galloping instability of this open cross section deck. New wind tunnel tests were therefore carried out in grid-generated turbulent flow, characterized by an integral length scale comparable to the bridge deck height and an intensity of 9% to 15%. For the interested wind angles of attack around null, static tests first indicate the incident turbulence is able to promote an even higher galloping factor than that in smooth flow, while the Strouhal number shows a decrease. This suggests a higher proneness for the galloping and vortex induced vibration to interact. In aeroelastic tests, however, the typical unsteady galloping instability due to the interaction with vortex induced vibration has never been observed. Instead, the unsteady galloping is initiated in a more complicated manner: unrestricted oscillation arises at a reduced wind speed clearly higher than the Kármán-vortex resonance one even for a very low Scruton number (the mass-damping parameter), combined with the absence of any Kármán-vortex excitation. Nevertheless, similar to the smooth flow condition, the nosed-up 4° remains to be the most unfavorable wind angle of attack in turbulent flow, featuring the lowest galloping onset in the low Scruton number condition. Finally, dependent on the magnitude of Scruton number, it is able to conclude that the incident turbulence can either suppress or promote the galloping instability of this bridge deck.

Fatigue assessment of steel-UHPC composite deck with a thin polymer overlay in a long-span suspension bridge under static and random traffic loads

Steel-ultra-high performance concrete (UHPC) composite deck emerges as a novel structure that is promising to improve the fatigue performance of orthotropic steel deck (OSD). However, a long-span suspension bridge has a strict requirement on the self-weight of a steel-UHPC composite deck because it is susceptible to dead load variations. This study evaluates the fatigue performance of the steel-UHPC deck with a thin polymer overlay (TPO) in the Yichang Yangtze River Highway Bridge, a long-span suspension bridge, under static load and random traffic flow. The measured strains at the fatigue-prone details were employed to calculate the equivalent stress ranges and total fatigue life of the steel-UHPC deck. A three-dimensional finite element model was established and validated by experimental measurements to evaluate the steel-UHPC deck’s stiffness and the TPO layer’s crack resistance. The differences between the stress values predicted by the validated model and the experimentally measured ones were around 5%. The results showed that the steel-UHPC deck with TPO significantly reduced fatigue-prone details’ equivalent stress ranges without increasing the dead load. The maximum stress reduction at various details reached 62%, and the total fatigue life at each detail in the steel-UHPC deck reached infinite life. The TPO layer has enough crack resistance in case the deck is overloaded by 50%. Compared with the original deck, the steel-UHPC composite deck improves the OSD’s local stiffness and reduces relative deformation between structural components, thus reducing the stress ranges at fatigue-prone details and improving the bridge deck’s fatigue performance. The results can provide a reference for the design and retrofit of the deck overlay of the long-span suspension bridge with OSD.

Saleyard Bridge, UK – an improved approach to precasting steel–concrete composite bridge decks

Saleyard Bridge carries the A465 Heads of the Valleys Road over the River Clydach near Gilwern, Monmouthshire, UK. It comprises a 67 m single-span steel–concrete composite multi-girder superstructure made integral with the abutments. A full-depth precast deck was chosen to tackle site constraints and improve constructability. The alternative precast panel connection detail developed used straight laps to overcome the problems that can arise from using typical U-bar loop type connections between precast deck panels. The successful use of the precast panels proved that a deck design with straight laps was a practical alternative. The ability to increase the multi-beam centres and avoid cantilever edge formwork created a more economical solution with savings estimated at £500 000. The paper examines the detailed design and construction planning needed to realise the savings and speed up construction as well as improving site safety. The lessons learnt are also applicable to the wider use of precast panels as an alternative to in situ concreting.

Shrinkage effect and mechanical performance of steel-ultra-high performance concrete composite deck under negative bending action

Shrinkage effect can result in damages in steel-UHPC composite decks. And these damages may even cause mechanical performance degradations. The details are critical to deck design practice and evaluation theory establishment while not being clearly understood. In this study, static shrinkage monitoring and negative bending tests on two full-scale segmental composite deck specimens (D12 and D16) were sequentially conducted. 12-mm- and 16-mm-diameter reinforcements were respectively embedded in the specimens. Simulation and parametric analysis were executed as well for further understanding. The 90 days static shrinkage monitoring results showed the maximum induced compressive strains on reinforcements of D12 and D16 were 559 με and 328 με. The maximum compressive strains on steel deck plates were 80 με and 82 με. It indicated shrinkage effect cannot be ignored. The bending test results showed the UHPC tensile strain maximums were 1458 με and 1149 με in the two specimens when the maximum UHPC crack width was 0.10 mm. Moreover, the simulation analysis results also showed that the model with 90 days shrinkage effect had a 16% lower bending secant stiffness at the load level equivalent to allowable UHPC crack width. And the reduction increased to nearly 40% when the crack width reached 0.10 mm. In addition, the parametric analysis showed that a strain-hardening feature could be favorable to delay the UHPC damage evolution compared with a strain-softening one with relatively lower tensile strength. These results provided important support to the design practice of steel-UHPC composite decks.

Tensile behavior of a prefabricated Steel–UHPC composite deck system with notched perfobond strips

This paper proposes a prefabricated steel–ultra-high-performance concrete (UHPC) composite deck (PSUCD) system equipped with notched perfobond strips (NPBLs) for long-span cable-stayed bridges. Compared with the use of an ultra-thin UHPC overlay, the proposed deck system better leverages the high compressive strength of the UHPC. Seven full-scale composite panel specimens with varying details of joint interfaces and shear connectors are subjected to tensile tests. The experimental results reveal that compared with a monolithic UHPC layer, the tensile strengths of the UHPC layer at the initial and nominal cracking (corresponding to a maximum crack width of 0.05 mm) are reduced by 47 % and 64 %, respectively, when flat joint interfaces are introduced and by 16 % and 40 %, respectively, when the interfaces are rectangular-tooth-shaped. The higher steel reinforcing ratio derived from the use of NPBLs placed across the joint interfaces leads to a distinct improvement in the post-cracking performance of the wet joints. Considering the weakened tensile strength and sectional area ratio of the joint interfaces, a prediction method for the crack widths at the wet joints in PSUCD systems is developed, and its prediction accuracy is verified.

Performance of semi lightweight concrete composite deck slabs under falling mass

In the present scenario probability of unexpected and accidental loading is high for the infrastructures. There is an urgent need to analyse these structures to check their viability against impact load. Composite structures are currently used to utilize the benefits of different materials. Past research works focused on the response of composite slabs under static load. Studies related to the impact response of composite slabs are limited, and the behaviour of less dense slabs is still to be explored. There is a demand to focus on the reaction of semi-lightweight aggregate concrete for composite grooved trapezoidal decking slabs subjected to drop mass impact. The study focused on the cushioning effect of six composite slab specimens (1000 mm × 930 mm × 80 mm) along with welded wire mesh and steel fibers as secondary reinforcements. Two were cast using control concrete (NC), and four were cast using lightweight concrete (LC). The collision was achieved by dropping a 55 kg steel cylinder to hit the center of the slab from a height of 1 m. Numerical modeling and analysis of similar slabs under impact load were carried out in ANSYS. The parameters concentrated are impacted force–time history, acceleration, crack pattern, bond-slip behaviour, and stress contours. The results show that lightweight concrete with welded wire mesh as secondary reinforcement could be effectively utilised as a cushioning layer for the composite deck system under falling mass scenarios.