Composite Arches Research Articles

Experimental and numerical studies on the behavior of corrugated steel-sprayed ECC composite arches with full-shear-connection

This paper proposes a novel corrugated steel-sprayed ECC (CSSECC) composite arch, which possesses high load-bearing capacity and fast construction speed. To investigate the ultimate load-bearing capacity, composite effect, and key mechanical indices, five 6 m-span arch specimens were tested. A finite element model was developed, and parametric analysis was conducted. The results indicate that the ultimate load-bearing capacity and damping ratio of the CSSECC composite arch specimens can reach 3.4 and 6.5 times that of the corrugated steel (CS) arch, respectively, and increasing the ECC thickness significantly enhances the damping ratio. Both studs and epoxy resin contribute to the composite effect, but studs are more reliable than epoxy resin even though their design shear connection degree is the same at 1.2. Finally, a design method for the stability bearing capacity under axial compressive was proposed.

Static behavior of corrugated steel-shotcrete composite arches

A new type of corrugated steel-shotcrete composite (CSSC) arch is proposed, which possesses the advantages of both high load-bearing capacity and ease of construction. Thus it is particularly suitable for bridges, culverts, shafts, and other projects. In this study, the static behavior of the CSSC arch under three-point loading was investigated experimentally and numerically. Four specimens with different rise-span ratios (1/2, 1/8), different spans (3 m, 6 m), and different locations of shotcrete lining (shotcrete outer lining, shotcrete inner lining) were tested. The test results show that the load-bearing capacity and initial stiffness of the CSSC arch could reach 6.8 times and 13.9 times that of the corrugated steel (CS) arch, respectively. When the load was less than 0.4 times the load-bearing capacity of the specimens, CS and shotcrete worked together. After that, the composite effect between CS and shotcrete was weakened. The ductility of the shotcrete outer lining CSSC arch is better than that of the shotcrete inner lining CSSC arch. A finite element model (FEM) was developed to investigate the influences of key parameters on the load-bearing capacity, including the thickness of materials, the strength of materials, the rise-span ratios and spans. Furthermore, calculation methods were proposed to predict the axial compressive capacity of the CSSC arch.

Investigation of the in-plane mechanical behavior of timber and steel–timber composite arches

This research investigates the structural characteristics of steel-timber composite (STC) structures through a comprehensive investigation involving five-point bending tests conducted on both the timber arch and the STC arch. The proposed STC arch configuration employs glulam panels bonded to the steel arch using adhesive, effectively restraining the internal steel components and mitigating the risk of buckling. By analyzing the test results, mechanical behaviors of the specimens were observed, including failure modes, load–displacement curves, and load–strain responses. Notably, the ultimate load-bearing capacity of the STC arch exhibited an approximate 28.44% increase compared to that of the timber arch, while maintaining a steel ratio of 10%. The steel ratio, defined as the proportion between the cross-sectional area of the H-shaped steel and the total cross-sectional area, was a critical factor to evaluate both the improvement effect and economic benefits. Additionally, employing finite element models, the influence of steel strength, timber strength, and steel ratio on the ultimate load-bearing capacity was demonstrated. Furthermore, the proposed analytical methodologies can be effectively employed to evaluate the mechanical performance of the STC arch, offering a valuable framework for assessment.

Nonlinear analysis of thermal–mechanical bending of laminated composite shallow arches reinforced with GPLs

The current research presents an analysis on the nonlinear thermal and mechanical bending problems of nanocomposite arches reinforced by graphene platelets. The graphene nanofillers are distributed through the thickness of the composite arch as the uniform or functionally graded patterns. Thermo-mechanical properties of the nanocomposite arch are evaluated using the Halpin–Tsai rule of mixtures approach. The multi-layered thick arch with shallow curvature is assumed to rest on an elastic nonlinear medium. Equilibrium equations of the assumed arch are obtained using the principle of virtual work and considering the third-order shear deformation theory with the von Kármán type of nonlinearity. The nonlinear governing equations are solved for the nanocomposite arch with immovable simply-supported and clamped–clamped boundaries by using a perturbation-based technique. Different numerical results are presented in this paper to evaluate the effects of curvature ratio, slenderness ratio, elastic medium, and the weight fraction and distribution pattern of GPLs on the thermal and mechanical bending behaviors of composite arches.

Evaluation of static responses for layered composite arches

Abstract Layered composite materials are widely used across a variety of sectors, including the automotive industry, aerospace engineering, offshore, and various mechanical domains, because of their strong yet lightweight structures. Therefore, various emergent theories are available on the deformation of layered beams. The previous research studies are insufficient as they are based on deformation of layered composite and sandwich arches with simply supported (SS) end conditions. Therefore, it is a good opportunity for researchers to investigate the arches using exponential shear deformation and normal deformation theory. The leading hypothesis mainly adds to the research of bending for sandwich and layered composite arches adopting the exponential theory. The present theory does not require any shear correction factor to satisfy zero transverse shear stress condition at the bottom and top fibers of arches. Governing equations and associated end conditions are derived through principle of virtual work. Navier’s techniques used for sandwich and layered composite arches are SS boundary conditions subjected to uniformly distributed load. The results of the current study showed that the exponential normal and shear deformation theories may be used to evaluate static responses for layered composite and sandwich arches. The obtained results from the present theory are validated through the results available in published literature.

Thermomechanical in-plane dynamic instability of asymmetric restrained functionally graded graphene reinforced composite arches via machine learning-based models

Thermomechanical in-plane dynamic instability of asymmetric restrained functionally graded graphene reinforced composite arches via machine learning-based models

Experimental study on the ultimate bearing capacity of damaged RC arches strengthened with ultra-high performance concrete

With the deterioration of the infrastructure and the increasing traffic volume, the service performance of bridge structures dramatically dropped. Strengthening and retrofitting these bridges with ultra-high-performance concrete (UHPC) can effectively improve their mechanical properties and durability. In this paper, the experimental investigation of the behavior of damaged RC arches strengthened with UHPC is presented. Three strengthened arches, including one arch strengthened with C50 (RC1-C50) and two arches strengthened with UHPC (RC2-UHPC, RC3-UHPC), were tested under asymmetric load. Load-deflection behavior, crack propagation pattern and hinge formation mechanism are extensively studied. Results indicated that the initial crack load and ultimate bearing capacity of composite arches strengthened by UHPC were respectively enhanced by 185% and 186%, showing good effects of strengthening and toughening on the original arch. On the premise of closing the cracks in the original arch ring, the stiffness and ductility of the composite arch strengthened with UHPC (RC2-UHPC) were improved by 58% and 34%, respectively. Different from the arch strengthened with C50 (RC1-C50), no obvious cracking and separation phenomena were observed in the interface of composite arches strengthened with UHPC in the whole process of eccentric loading. The combination of keyway and planting bar (rigid and flexible) can provide reliable bonding between the UHPC and the original structure. Finally, the calculation model for predicting the cracking load and ultimate capacity of the composite arches were proposed, and the calculation results are in good agreement with the experimental results.

Experimental and numerical study on slender concrete-filled steel tubular arches subjected to tilting loads

Concrete-filled steel tubes (CFST) are economical for arch bridges because of their high compressive strength and efficiency in construction. Compared to the traditional concrete arches, the CFST arches usually have a large slenderness ratio, which makes the arches more prone to buckling. Despite this, limited experimental investigations have been performed on the buckling behaviour of CFST arches. In this study, a buckling test was performed on two 9 m long CFST parabolic fixed arches having a single circular cross-section with one arch subjected to a central concentrated tilting load and the other to half-span three-point tilting loads. Finite element (FE) models using solid elements were built and validated against the test results, with which the influences of the residual stress on the buckling behaviour of the composite arches were analysed and the confining pressure distribution was obtained. The FE models using beam elements were then built to investigate the confinement effects on the buckling behaviour of the CFST arches. Relatively significant confinement effects were found on the arches and were considered in the FE modelling. The residual stress had a fairly limited influence on the load-carrying capacity of the arches and was ignored in the FE models. Both the built FE models using solid and beam elements performed well in predicting the buckling behaviour of the CFST arches.

Flexural behaviors of CFRP strengthened laminated bamboo arches

Arch structure is a special type of structure, mainly used in bridges, underground buildings and some large public buildings like stadiums. Previous studies have shown that bamboo composite arches are prone to interfacial failure under flexural loading, so that composite materials are considered to be used to reinforce the bamboo laminate. Three different Carbon fiber reinforced plastic (CFRP) reinforcing methods were adopted to strengthen the Laminated bamboo arch (LBA), and three-point bending experiments were conducted to compare the flexural mechanical property of the LBA before and after strengthening. The failure of the LBA is mainly induced by the interfacial delamination. Wrapping CFRP sheets around the LBA can restrain the interlaminar delamination and improve the load carrying capacity of the LBA. In this research, the peak load can be improved by 26.54%. It is also found that the wrapping at the vault is the most important while the wrapping at the haunt has less important effect to improve the load carrying capacity. With CFRP wrapping the utilization ratio of the fiber tensile strength can reaches 0.85, or even close to 1.0.

Buckling mechanism of thin-walled arches with composite polyhedral shapes

The present work is concerned with the pressure capacity of the thin-walled composite arches with different polyhedral shapes. The analytical derivation process involves the employment of the energy theory, the thin-walled shell principle, and the assumed displacement field. The total potential energy formulae of the polyhedral arch are expressed analytically. By taking the first derivatives of the energy function to the two unknowns, it is effortless to obtain two equations of equilibrium. The critical buckling pressure and the equilibrium paths are expressed by solving these two equations of equilibrium simultaneously. Subsequently, good agreements are reached when the proposed buckling pressure is compared with other closed-form expressions for a circular arch with a constant radius. Finally, the effect of the geometric parameters on the critical buckling pressure is analyzed. An enhancement factor is introduced to express the ratio of the buckling pressure between the arch with the polyhedral shapes and the traditional circular cross-section. It is found the enhancement factor reduces when the values of N increases and the ratio of thickness-to-radius increases, respectively. Therefore, a polyhedral arch with a small value of N and a small ratio of thickness-to-radius is recommended in engineering applications.

Analytical Prediction for Nonlinear Buckling of Elastically Supported FG-GPLRC Arches under a Central Point Load.

In this paper, we present an analytical prediction for nonlinear buckling of elastically supported functionally graded graphene platelet reinforced composite (FG-GPLRC) arches with asymmetrically distributed graphene platelets (GPLs). The effective material properties of the FG-GPLRC arch are formulated by the modified Halpin–Tsai micromechanical model. By using the principle of virtual work, analytical solutions are derived for the limit point buckling and bifurcation buckling of the FG-GPLRC arch subjected to a central point load (CPL). Subsequently, the buckling mode switching phenomenon of the FG-GPLRC arch is presented and discussed. We found that the buckling modes of the FG-GPLRC arch are governed by the GPL distribution pattern, rotational restraint stiffness, and arch geometry. In addition, the number of limit points in the nonlinear equilibrium path of the FG-GPLRC arch under a CPL can be determined according to the bounds of successive inflexion points. The effects of GPL distribution patterns, weight fractions, and geometric configurations on the nonlinear buckling behavior of elastically supported FG-GPLRC arches are also comprehensively discussed.

Wrapping and anchoring effects on CFRP strengthened reinforced concrete arches subjected to blast loads

AbstractThis paper studies the effectiveness of bonding carbon fiber reinforced polymer (CFRP) with additional wraps or anchors to strengthen reinforced concrete (RC) arches resisting blast loads, which is of great significance to optimize the CFRP strengthening methods. To improve the anti‐explosion behavior, RC arches are bonded with CFRP sheets in longitudinal and transverse directions, and anti‐explosion behaviors were investigated through experiments. The performance of strengthened arches is discussed in terms of damage degrees in contrast to the un‐strengthened arch. Under explosive loading, the resistance of composite arches to spalling, shearing, and bending is much better than that of control arch. The results show that the anti‐explosion effect of wrapping or anchoring, which can prevent CFRP debonding or peeling‐off, is much better than only bonding CFRP in the longitudinal direction. Besides, simplified analysis models are proposed to assess the blast‐resistant capacity of CFRP strengthened RC arches, which show good agreement with the experiment.

Geometrically nonlinear buckling of graphene platelets reinforced dielectric composite (GPLRDC) arches with rotational end restraints

This paper presents an analytical investigation on the nonlinear buckling behavior of graphene platelets reinforced dielectric composite (GPLRDC) arches with rotational end restraints under applied electric and uniform radial load. The effective materials properties of GPLRDC, including the elastic modulus and dielectric permittivity, are estimated by employing effective medium theory (EMT). The analytical solutions for nonlinear equilibrium, critical load of limit point buckling and bifurcation buckling of the GPLRDC arch are derived according to the principle of virtual work. The critical geometric parameters and electric voltage governing the buckling mode switching behavior are also identified and discussed. The effects of graphene platelets (GPLs) weight fraction, size and geometry, applied DC voltage, AC frequency, as well as geometry of the arch on the buckling behavior are examined comprehensively. It is found that the dielectric property of the GPLRDC has significant effects on the buckling behavior of the GPLRDC when the GPLs concentration exceeds the percolation threshold. The nonlinear buckling behavior of the GPLRDC is quite sensitive to the AC frequency within a certain range. Furthermore, the change of the applied voltage can switch the buckling mode and even the number of limit points of the GPLRDC arch.

Multiple Equilibria and Buckling of Functionally Graded Graphene Nanoplatelet-Reinforced Composite Arches with Pinned-Fixed End

This paper presents an analytical study on the multiple equilibria and buckling of pinned-fixed functionally graded graphene nanoplatelet-reinforced composite (FG-GPLRC) arches under central point load. It is assumed that graphene nanoplatelets (GPLs) in each GPLRC layer are uniformly distributed and randomly oriented with its concentration varying layer-wise along the thickness direction. The Halpin–Tsai micromechanics-based model is used to estimate the effective elastic modulus of GPLRC. The non-linear equilibrium path and buckling load of the pinned-fixed FG-GPLRC arch are subsequently derived by employing the principle of virtual work. The effects of GPLs distribution, weight fraction, size and geometry on the buckling load are examined comprehensively. It is found that the buckling performances of FG-GPLRC arches can be significantly improved by using GPLs as reinforcing nanofillers. It is also found that the non-linear equilibrium path of the pinned-fixed FG-GPLRC arch have multiple limit points and non-linear equilibrium branches when the arch is with a special geometric parameter.

In-plane and out-of-plane free vibrations of functionally graded composite arches with graphene reinforcements

This article presents in-plane and out-of-plane free vibration analyses of functionally graded graphene nanoplatelets reinforced composite (FG-GPLRC) arches. The arch is composed of multiple layers reinforced with graphene nanoplatelets (GPLs) that are evenly distributed in each layer but its weight fraction varies layer-by-layer in the thickness direction. The effective material properties are calculated by Halpin-Tsai micromechanics model for Young’s modulus and the rule of mixture for both mass density and Poisson’s ratio of each GPLRC layer. Analytical solutions are obtained for the fundamental frequencies of the in-plane anti-symmetric vibration and out-of-plane vibration of both fixed and pinned FG-GPLRC arches by using Hamilton’s principle. A comprehensive parametric study is carried out to investigate the influences of distribution pattern, concentration and dimensions of GPLs as well as the geometrical parameters of the arch on the fundamental frequency of the FG-GPLRC arch. It is found that the fundamental frequency of the arch can be considerably improved by adding a lower quantity of GPLs as reinforcing nanofillers.

A theoretical and experimental study on in-plane buckling of orthotropic composite arches under an arbitrary radial point load

Nonlinear in-plane buckling behavior of fixed orthotropic composite arches under an arbitrary radial point load is investigated theoretically, numerically and experimentally in this paper. Analytical solutions that include the bending-stretching coupling effect are developed for both critical buckling load and nonlinear equilibrium path and are validated by the finite element model. A variable-speed displacement control loading system with automatic loading direction adjustment is designed and set up for the test to record the complete buckling evolution process. Comprehensive analytical and experimental results for the critical buckling load and nonlinear equilibrium path of the arches are presented in both tabular and graphical forms, followed by a parametric study with a particular focus on the influences of loading position, stacking sequence as well as the rise-span ratio on the buckling load. Research results indicate that the buckling mode of the composite arch is highly dependent on the modified slenderness ratio. Both buckling mode and the switching modified slenderness ratio are significantly influenced by the loading position. The buckling load is also highly sensitive to stacking sequence and decreases as the 90° lamina is placed far away from the mid-plane.

Nonlinear in-plane buckling of fixed shallow functionally graded graphene reinforced composite arches subjected to mechanical and thermal loading

• Nonlinear in-plane buckling of FG- GPLRC arch subjected to uniform radial load and temperature field is investigated. • Analytical solutions for the limit point and bifurcation buckling loads are derived. • Parametric studies of different parameters on the nonlinear equilibrium path and buckling behavior are conducted. • Switches between limit point buckling, bifurcation buckling and no buckling are obtained and discussed. The nonlinear in-plane buckling analysis for fixed shallow functionally graded (FG) graphene reinforced composite arches which are subjected to uniform radial load and temperature field is presented in this paper. The arch is composed of multiple graphene platelet reinforced composite (GPLRC) layers with gradient changes of concentration of graphene platelets (GPLs) in each layer. The principle of virtual work, combined with the effective materials properties estimated by the Halpin-Tsai micromechanics model for GPLRC layer, is used to derive the nonlinear buckling equilibrium equations of the FG-GPLRC arch, and then the analytical solutions for the limit point and bifurcation buckling loads are obtained. Comprehensive parametric studies are conducted to explore the effects of various distribution patterns and geometries of GPL, temperature field and arch geometry on the nonlinear equilibrium path and buckling behavior of the composite arch. The influence of temperature on the geometric parameters which are defined as switches between limit point buckling, bifurcation buckling and no buckling are also discussed. It is found that a higher temperature field can increase the buckling loads of the FG-GPLRC arch but reduce the value of the minimum geometric parameters that switching the buckling modes. The results also show that even a small amount of GPLs filler content can increase the buckling loads of the FG-GPLRC arch considerably, and distributing more GPLs near the surface layers is the best pattern to enhance the buckling performances of FG-GPLRC arches.

On the vibration analysis of laminated composite parabolic arches with variable cross-section of various ply stacking sequences

The main objective of this study is to perform the free and forced vibration analysis of transversely isotropic and laminated composite parabolic arches with a continuous cross-section variation. The anisotropy of the material of the arch, effects of the rotary inertia, and shear deformations are considered. An efficient unified numerical procedure of the Complementary Functions Method and Laplace transform is applied to solve the strong form of the differential equations that govern the dynamic response of the above structures. The validity and the accuracy of the presented scheme are tested by means of several comparisons with available literature and results of ANSYS. The presented approach has proven to be an accurate and stable numerical method. It is believed that derived results can be used as benchmark solutions for validation of related works in the future.

Experimental Study of the Mechanical Performance of Corrugated Steel Plate-Concrete Composite Structures

This paper presents a comparative study on the composite structure of Corrugated Steel Plate (CSP) with normal and rubberized concrete. One CSP-normal-concrete plate and two CSP arch structures composited with different concretes are established. A theoretical section-property deduction is derived, which demonstrated that the flexural rigidity of such composite structure increased notably. Static and dynamic mechanical experiments are also conducted. Experimental results agree with expectations, and the measured results on plate structures verified the effectiveness of the analytical and numerical solutions. Comparing the deflection of two composite arches shows that the rubberized concrete composite arch has smaller flexural and compressive stiffnesses, resulting in larger deflection. The rubberized concrete composite arch has higher steel stress, lower concrete stress and better energy-dissipating capacity compared with the normal concrete composite arch. Therefore, the CSP-rubberized concrete composite structure is more suitable for anti-shock and earthquake-resistant structures.

A numerical study of the seismic response of arched and vaulted structures made of isotropic or composite materials

The Generalized Differential Quadrature (GDQ) and Newmark methods are chosen to solve time integration problems such as the dynamics of composite arches and vaults with constant and variable cross-sections, under seismic impulse loading applied at the base. A 2D Equivalent Single Layer (ESL) shell theory is used to analyze the problem numerically, where the governing equations of motion are solved in a strong form without passing through any variational formulation. The total time interval is discretized in time steps, as required by a Newmark approach, and the GDQ method is applied to solve a system of linear ordinary differential equations for each time step. The accuracy of the proposed method in predicting the dynamic response of the arched or vaulted structures is demonstrated by comparing the GDQ-based results for different geometries and external loadings, with the ones obtained with a standard Finite Element Method (FEM).