Compressive Capacity Research Articles

Axial compressive behavior and load carrying capacity prediction of prefabricated UHPC tube filled with seawater sea-sand coral aggregate concrete

To reduce construction costs, seawater, sea sand, and dead coral are often used in concrete buildings on distant islands. Such seawater-sea sand coral aggregate concrete (SSCAC) typically has insufficient mechanical properties and high chloride ion content. In this paper, a novel composite column, named SSCAC-filled ultra-high performance concrete (UHPC) tube (SFCT), is proposed and studied. The SFCT column combines a prefabricated fiber reinforced polymer (FRP) hoop reinforced thin-walled UHPC tube with the infill SSCAC. A total of 36 relative large-scale columns were conducted for axial compression tests. The SFCT columns showed a multi-crack failure mode on the surface of the tube without obvious peeling-off of the UHPC cover in the whole loading process. The test results reveal that the UHPC tube in the composite system effectively takes on the additional load released by the inner SSCAC during compacting due to the porous nature and low strength of coral aggregates. Therefore, the compressive behavior of the pre-peak stage of SFCT column is effectively improved compared with existing SSCAC confined by FRP tube or hoops, especially important is increased the axial stiffness. The proposed composite system effectively combines the ultra-high compressive performance of UHPC and the lateral confining effect from FRP hoops. A model was also proposed for predicting the axial load carrying capacity of SFCT columns. The analysis results indicate that selecting relatively thinner UHPC tube in SFCT composite system and using relatively flexible and low-cost basalt FRP (BFRP) and glass FRP (GFRP) hoops instead of carbon FRP (CFRP) hoops as the lateral confining component are economical and could be reasonable measures for manufacturing the composite columns.

Axial Compression Performance Test and Bearing Capacity Calculation of RC Square Column Strengthened by FRP Textile Grid-reinforced ECC

In order to investigate the strengthening effect of FRP textile grid reinforced ECC composite (abbreviated: TRE) restrained RC columns, this study conducted experimental and theoretical studies on the axial compression performance of TRE strengthened RC square columns with RC square columns as the research object. The effects of the chamfer radius of the original column, the type of FRP grid and the number of layers of the grid on the axial compression performance of the TRE-strengthened RC square column were considered. The axial compression tests showed that the strengthened layer exhibited excellent crack control, the reinforced column cracked as a whole without breaking when it was damaged, and the strengthened layer adhered well to the core concrete. Compared with unstrengthened specimens, the compressive strength, ductility and deformation capacity of the RC square column under TRE restraint were significantly higher. The increase of chamfer radius of square column makes the TRE restraint effect better. Increasing the number of grid layers can significantly improve the ultimate bearing capacity and ductility of the strengthened specimens. The effects of TRE strengthening methods with different FRP grids differed, with the same number of grid layers, the ultimate bearing capacity of the specimens strengthened with CFRP grid reinforced ECC was higher, and the cracking load of the specimens strengthened with BFRP grid reinforced ECC was higher. A model for calculating the ultimate bearing capacity of the TRE-constrained RC square column was established, and the validity of the model was verified by comparing the results of this test.

Development of high strength self compacting concrete with waste glass and waste marble

This research investigates sustainable options for self-compacting concrete (SCC) using waste glass (WG) as a substitute for cement and the addition of marble waste as a filler material. The replacement levels of WG varied from 0 % to 20 %, with increments of 5.0 % while 10 % marble waste was added as filler to improve the SCC flowability. A series of experiments on SCC flow properties, mechanical performance, cracking behavior, failure patterns, and microstructure were conducted. Results indicate that WG increased the flowability of SCC. All the WG substituted mixes fall within the SCC limit and possessed better filling and passing ability. Furthermore, mechanical performance was enhanced with the substitution of WG due to micro-filling and pozzolanic action. Maximum compressive strength was achieved at 10 % substitution of WG which improved the compressive capacity of SCC by 17 % and 20 % more than from the reference SCC blend at 28 and 56 days respectively. However, higher percentages of WG (20 %) decreased the compressive capacity of SCC but still greater than reference SCC. Scanning electron microscopy (SEM) and fourier transform infrared (FTIR) analysis provide visible and chemical proof of the microstructural improvements resulting from pozzolanic reactions and micro-filling action. However, WG slightly improved tensile strength and had no impact on the failure pattern, which resulted in brittle failure without any warnings (cracks). Therefore, the study recommends additional research to improve the tensile strength and avoid brittle failure of WG based SCC by adding fibers.

Modelling and lock-seam effects on compressive behaviour of concrete-filled helical corrugated steel tubes

Concrete-filled galvanized helical corrugated steel tube, abbreviated as CFCST, is a new type of composite member that has great potential to be used in seismically active regions or highly corrosive environments. However, the unique lock-seam connections of helical corrugated steel tube (CST) result in high difficulty in precise simulation analysis, and the effects of such connections on the mechanical properties are not clear, so further investigations are needed. This paper attempts to present a detailed finite element (FE) model of CFCST with the real dimension of lock-seam connections, and then investigate the effects of lock-seam connections on the basic compressive behaviour of CFCST stub columns. The FE models are developed with the consideration of the real shape of helical CST, the non-linearity of each constituent material, and the interfacial properties at lock-seam regions. The simulated results are verified carefully through comparisons against experimental results of 41 stub columns under axial compression in terms of failure modes, load–displacement histories, and local stress developments. The influence of lock-seams on the working mechanisms has been particularly investigated and discussed. Parametric studies have also been conducted to investigate the compressive behaviour of the CFCST. Finally, simplified design methods for axial compressive bearing capacity are proposed.

Experimental investigations on the compression capacity of rectangular steel tubular columns strengthened with intermittently welded angle steel

Many steel structure buildings in China were built from the 1970s to the 1980s, and they have been in service for decades. However, due to factors such as changes in their functionality, prolonged disrepair, and erosion of the surrounding environment. Studying the strengthening of many existing steel structures will become an important measure during the “reinforcement period.” Welding angle steel on the surface of steel columns for reinforcement is a commonly used method in practical engineering. However, the traditional continuous welding of angle steel to reinforce rectangular steel tube columns results in a relatively large welding workload on the construction site, extending the construction period and increasing the engineering cost, which cannot guarantee high welding quality. To reduce the workload of on-site welding and the cost of construction reinforcement, intermittent welding is proposed. This article designed 9 test specimens for axial and eccentric compression tests to obtain the failure modes, ultimate bearing capacity, and stress distribution of the cross-section of steel tube columns reinforced with different intermittent welding angle steels. The experimental results indicate that intermittent welding can replace continuous welding for the reinforcement of steel tube columns, significantly reducing on-site welding workload and fully utilizing the role of angle steel reinforcement. If the length of the intermittent welding is too large, local buckling will occur, thereby weakening the reinforcement effect of the angle steel. The existence of batten plates can improve the ultimate bearing capacity of intermittent welded angle steel tube columns. Comparative analysis was conducted using a finite element model, which revealed the force transfer mechanism and ultimate bearing capacity of intermittent welding angle steel reinforced steel tube columns. The optimal weld spacing and weld length for intermittent welding of angle steel to reinforce rectangular steel tube columns provide a theoretical reference for the design and application of practical reinforcement engineering.

Compression behavior of 4D printed metamaterials with various Poisson's ratios

In this study, three types of cellular metamaterials with negative/zero/positive Poisson's ratio and vibration isolation effects were devised and fabricated based on 4D printing of shape memory polymers. The compressive properties and energy absorption capacity of three cellular metamaterials at variable temperatures were evaluated by finite element simulations and compression experiments. To explore the application possibilities of 4D printed cellular metamaterials in deformable structures, shape recovery experiments were carried out, and the results showed that the three types of cellular metamaterials exhibited a high shape recovery rate. The vibration modes and vibration isolation capabilities of 4D printed cellular metamaterials were investigated for three types of cellular metamaterials with negative/zero/positive Poisson's ratio. In addition, based on the deformation reversible capability of the structure, the vibration isolation capability of three cellular metamaterial structures was investigated under different deformation stages. The results demonstrate that the cellular metamaterials with zero Poisson's ratio possess superior vibration isolation capability compared to negative or positive Poisson's ratio cellular metamaterials at different deformation stages by a comprehensive analysis. The methods and conclusions presented in this study will guide the design of functionalized cellular metamaterials with high energy absorption, strong vibration isolation, and autonomous deformation ability.

Analysis and design of axially loaded ring-beam joints connecting steel tubed-RC column and RC beams

This work proposes a reinforced concrete (RC) ring-beam joint system for connecting circular tubed-reinforced concrete (TRC) columns and RC beams. In the joint zone, a thin-walled core steel tube is embedded to reduce the size of the RC ring beam, which is beneficial to construction convenience and architectural layout. A simplified model is established to allow for both the confinement effect of the core steel tube and the load-carrying capacity contribution of the ring beam. This simplified model enables the analysis of the load-resisting mechanism underlying the proposed joint, along with the derivation of an equation for its axial compression capacity. Furthermore, a high-fidelity finite element model is established and validated through test results. Parameter analysis was then conducted to assess the effects of concrete strength, yield strength of the steel tube, thickness of the steel tube, and height of the core steel tube on both the core steel tube stresses and the axial load-capacity of the joints. Formulas for calculating circumferential stresses and longitudinal stresses of the core steel tube are also proposed. The predictions agree well with the results obtained from test and parameter analysis. Lastly, design recommendations and procedures for the joint are proposed, and a design example is given with three types of joints details. The results demonstrate the advantages of the proposed joint in terms of convenient construction and favorable cost-effectiveness.

Eccentric compression capacity of circular CFST columns under random pitting corrosion

This study explores how random pitting corrosion affects the ultimate eccentric load-carrying capacity of corroded CFST columns at various corrosion levels. The research examines how the load-carrying capacity of circular steel tube concrete columns changes under eccentric loading conditions due to variations in the quality loss rate of the external steel tube caused by corrosion. The established finite element model is validated using existing experimental data, showing a high degree of accuracy. Additionally, the study investigates influencing factors, including corrosion thickness (tc/t), both constant and random corrosion (tc/t), eccentricity (e), corrosion pit diameter (Dc), material strength, and component dimensions. The findings reveal how these parameters affect the reduction of eccentric compressive load-carrying capacity. To visually illustrate this effect, the concepts of load reduction factors Rcs′ and Rc′ are introduced, representing the ratio of load-carrying capacity before and after corrosion. Based on extensive random finite element analyses, we propose a load-carrying capacity calculation formula for the eccentric load reduction factor applicable to corroded circular CFST columns. The study also demonstrates that axial compression can be considered a special case of eccentric loading with an eccentricity of 0. Consequently, by incorporating stability and eccentricity reduction factors, adjustments are made to existing axial load-carrying capacity prediction formulas, resulting in the calculation formula for the reduction factor Rc′. By measuring the local quality loss rate of the external steel tube of corroded circular CFST columns, it is possible to predict both axial and eccentric load-carrying capacities.

Experimental evaluation of axial compression performance of precast panels from bamboo-reinforced concrete

This research aimed to determine the performance of bamboo-reinforced concrete precast panels (BRCPP) subjected to axial compressive loads, validated using numerical simulations. Axial compressive load capacity, crack, and failure patterns were investigated and compared with steel-reinforced concrete precast panels (SRCPP) as a control. Eight panels were made with details of four BRCPP and SRCPP, having dimensions of 1200 × 400 × 50 mm3 each. The four SRCPPs consisted of two panels, produced in laboratories and two manufactured by local companies. The variations in bamboo reinforcement spacing were 150 mm and 180 mm, while the gap between steels was 180 mm, and panels were tested under axial compressive load. The results showed that the axial compressive load capacity of BRCPP with a bamboo reinforcement size of 12 × 12 mm2 at a distance of 150 mm was sufficient to meet the specifications of SRCPP panels produced by the local industry. Based on experimental, theoretical, and numerical simulation analysis, the performance of BRCPP showed suitability, making it a considerable choice, specifically for precast panels. The special advantage of BRCPP encompassed eco-friendliness and sustainability.

Energy absorption behaviors of a novel buffer lander-leg with Yoshimura core

In the current soft-landing system, the lander-leg and the buffer are two independent parts which may cause weight problem. The traditional mechanical buffers also have their own shortcomings such as small buffer stroke and being non-reusable. A Novel Buffer Lander-leg with Yoshimura core (NBLY) is proposed in this paper, inspired by the Buckling Restrained Brace (BRB). The design details of NBLY and parameter definitions of the core are presented. The finite element analysis modes have been employed to analyze the nonlinear mechanical behaviors of NBLY subjected to the cyclic loading. NBLY with four different core styles of hexagon, octagon, dodecagon and hexadecagon are analyzed and compared. The restraining ratio and cumulative dissipation energy ratio have been obtained to evaluate the energy absorption properties. The results show that the origami pattern has significant influences on the deformation ductility, plastic energy absorbing and axial load transferring to the core. The NBLY with octagon core has outstanding properties, especially the hysteretic energy dissipation and enhancement of compression capacity. The interaction mechanism between the core and encasing member constrains the deformation extensions and contributes to the frictional energy dissipation of the NBLYs. This paper provides a new conceptual design of buffer lander-leg for soft-landing missions. It can realize the reuse function as a buffer lander-leg with better loading-bearing and energy absorption behaviors.

Lessons learned from large-scale physical modeling of tapered jacking piles: HSDT

To provide an improved understanding of the behavior of screw piles in disturbed soil, as a series of companion papers, laboratory tests with full scale tapered jacking piles were performed in the current study. The designated tapered pile has the similar dimensions, material properties and cone-shaped bottom, with the exception of threads eliminated.
 The main objectives of this paper are to: (1) establish the robust and efficient simple high strain dynamic testing (HSDT) requirements for validating displacement tapered piles capacities while exploring the installation effect; (2) determine a correlation between static and dynamic bearing capacity in compression for steel tapered piles installed by jacking in sand with various relative densities.
 Out of nine large-scale laboratory expriments at Aalborg University Offshore Geotechnics Laboratory [1-3] with the tank filled with Aalborg University Sand No.1, this research exclusively presents some lessons learned from an exemplar tapered jacking pile installation (Test 4) in dry sand (relative density and its response to monotonic and impact loadings. The selected piles have diameter of D=76 mm and 89 mm with length of 2.07 m. The layout of the miniature CPTs carried out to measure soil state is shown in Fig. 1, with four CPTs performed following each jacking installation campaign to study the soil state after the installation of the piles (Fig. 1). In order to fulfill the objectives, the piles are installed by a static compression load that includes an unloading/reloading step, followed by dynamic testing in order to facilitate the determination of the bearing capacity (Fig. 2). The hammer test was carried out on both piles, by a hammer from increasing drop heights of 218, 418, 618, 818 and 1018 mm (Fig.3). The hammer consists of a sleigh with multiple attached steel plates weighting 19.31 kg on average and the sleigh itself weighs 18.55 kg. Tapered pile jacking resulted in dilation extending to a depth of 2.8when diameter exceeds from 76 mm to 89 mm. By contrast, in the region around pile P76, the soil was entirely densified. The tendency to densify the soil near tip area due to jacking installation is observed in both tests, where the initial viod ratio varied from 0.67 to 0.59 and from 0.63 to 0.57 corresponding to piles P76 and P89, respectively (Fig.4).
 Subseuqntluy, Danish Pile Driving Formulas (DDR) introduced by [4] was ustilised which is according to the required potential energy from a hammer stroke to exceed the pile penetration resistance. The mass of the hammer G is defined by:
 where elastic settlement =, A is cross-sectional area, E is the Young’s modulus, l is the installed length of pile which is approximately 1.9 m, and is the maximum static force required to install the pile. The efficiency factor is set as 1. During the impact loading tests, the settlement of the pile is measured with a 1 mm accuracy for each hammer stroke, and the limiting settlement, s was set to yield a certain level (0.1D) when the drop height is 618 mm. Thus, the dynamic bearing capacity = , and ratio= are shown in Table 1.

Simplified Method for Nonlinear Seismic Response Analysis of Corroded Pile-Supported Wharf

Fiber-based finite element analysis (FB-FEA) has been widely recognized for its ability to reproduce experimental results and is also a reliable method for evaluating the nonlinear seismic response of pile-supported wharves (PSWs). Design practice often employs frame analysis (FA) due to its easy implementation. To precisely reproduce the nonlinear seismic response of PSW using FA, it is necessary to configure mechanical properties such as the hinge property correctly. However, it is unclear whether the hinge properties proposed in previous studies can be applied to PSWs with spun piles. In this study, a novel FA method was developed to investigate the nonlinear seismic response of PSWs with corroded spun piles considering PC bar area reduction, deteriorated material properties, the bending stiffness reduction factor, and the moment–curvature relationship of the spun pile. The nonlinear seismic response of corroded PSWs was determined by performing pushover analysis using three methods: FA using the method of the previous study (FA-1), the proposed FA method (FA-2), and FB-FEA. As regards PSW foundations, vertical pile and batter pile configurations were considered. The pushover analysis results were compared in terms of several parameters, such as the natural period, plastic hinge formation, and load capacity of the corroded PSWs. The FA-2 results agreed very well with the FB-FEA results, while the FA-1 results were less precise with respect to the natural periods and load capacities of corroded PSWs. The results indicated that the bending stiffness reduction factor, moment–curvature relationship, and axial load–bending moment (P–M) capacity of the corroded spun piles should be appropriately defined. Corrosion had greater negative impacts on the compressive axial load and bending moment capacities of the spun pile than on its tensile axial load capacity.

Performance of Superabsorbent Polymer as Admixture in Hollow Concrete Blocks

This study investigates the efficacy of superabsorbent polymer (SAP) waste as an admixture in producing hollow concrete blocks. Using the central composite design (CCD) of the response surface methodology (RSM), the concrete blocks were created by adjusting the SAP percentage from 0.05% to 0.25%, with a constant amount of cement and sand ratios ranging from 2.00 to 4.00. After 28 days of curing, the blocks were evaluated for their compressive strength, density, and water absorption capacity. Analysis of Variance (ANOVA) was used to analyze the data. The results showed that the created hollow concrete blocks at optimum condition exceeded the Philippine National Standard and ASTM Standard of 4.14 MPa for compressive strength on non-loadbearing concrete masonry, with theoretical properties of compressive strength of 8.20 MPa, density of 1900 kg/cm3 and 5.28% water absorption at the optimized conditions after numerical optimization using the CCD. This innovation could reduce solid waste output and help the environment by using by-products from companies. This research provides valuable insights into sustainable construction materials and highlights the potential of using superabsorbent polymers in producing hollow concrete blocks.

Cyclic performance of middle partially encased composite braces

The utilization of reinforced concrete to fill the middle section of the H-shaped steel in middle partially encased composite brace (MPECB) effectively restrains the buckling deformation of the steel plates, mitigates compression instability, and enhances the compressive stiffness and bearing capacity of the brace component. To investigate the hysteresis performance and energy dissipation capacity of MPECBs, axial hysteresis tests were conducted on four MPECBs and one comparative H-shaped steel brace. The experimental results revealed that the failure mode of MPECBs involved warping deformation of flange plate and separation from the concrete. Compared to steel brace, MPECBs exhibited significantly improved energy dissipation capacity in the early loading stage, as well as enhanced compressive capacity, while showing minor change in tensile capacity. Additionally, finite element models (FEMs) were developed, and parameter analysis was performed. The FE analysis confirmed that the variations in reinforcing bars and stirrup spacing had a minor influence on the bearing capacity of MPECBs in comparison to modifications in the cross-sectional dimensions of H-shaped steel. However, reducing the stirrup spacing can enhance the utilization of the concrete in MPECB, allowing for its performance to be more effectively harnessed. Furthermore, the formula for calculating the tensile capacity of MPECB was proposed, and the design process for MPECB was summarized based on the calculation method.

Machine learning models for predicting axial compressive capacity of circular CFDST columns

Machine learning (ML), widely recognized for its advanced predictive capabilities, is progressively being employed in structural design. Concrete-filled double skin steel tubular (CFDST) members are extensively utilized due to their exceptional mechanical behavior. However, existing formulas encounter challenges in accurately calculating the axial compressive capacity of circular CFDST members, particularly when high-strength concrete and steel materials are involved, leading to complexity and low accuracy. This paper presents a data-driven framework that leverages the superior predictive performance of machine learning approaches to predict the axial compressive capacity of circular CFDST columns. Finite element models are developed through secondary development of ABAQUS using custom script, which are then validated against experimental data, confirming their effectiveness and applicability. A general database is established, comprising 226 test results and 550 finite element results obtained from the script, to facilitate the prediction of axial compressive capacity for circular CFDST columns. By incorporating the physical mechanisms of CFDST members and conducting correlation analysis, the input parameters for the machine learning models are determined. Decision Tree, Artificial Neural Network (ANN), K-nearest neighbor (KNN) and two ensemble methods including Random Forest, XGBoost, are trained and optimized using the database to provide accurate predictions. The results demonstrate that the KNN model exhibits superior performance and high accuracy, outperforming the four commonly used calculation formulas in the field, particularly for circular CFDST columns using high-strength materials. The proposed data-driven framework shows promising potential for achieving outstanding predictive performance.

Performance of Alkali-Activated Slag Concrete Masonry Blocks Subjected to Accelerated Carbonation Curing

This study investigates the effect of accelerated carbonation curing on the carbon sequestration potential, performance, and microstructure of alkali-activated slag mixes representing concrete masonry blocks (CMBs). The carbonation curing process parameters varied, including initial curing duration, carbonation curing duration, and carbonation pressure. Research findings showed that a maximum CO2 uptake of 12.8%, by binder mass, was attained upon exposing concrete to 4 h initial curing and 20 h carbonation curing at a pressure of 5 bars. The compressive strength and water absorption capacity improved with longer initial and carbonation curing durations and higher pressure. Upon subjecting to salt attack, the mass and strength of 28-day concrete samples increased, owing to the formation of Friedel’s salt and Halite. All mixes could be used as non-load-bearing CMB, with a 1-day strength greater than 4.1 MPa. Based on the global warming potential index, the carbon footprint of carbonation-cured, alkali-activated slag concrete masonry units was up to 46% lower than non-carbonation-cured counterparts. Research findings offer valuable information on the production of carbonation-cured, cement-free concrete masonry blocks to replenish natural resources, recycle industrial waste, and mitigate CO2 emissions.

Axial compressive behavior of the middle-supported irregular-shaped columns in modular aluminum houses

Modular folding aluminum houses (MFAHs) are new modular structures that can be folded, transported, and built directly on-site. In this study, the axial compressive behavior and design method of the middle-supported irregular-shaped columns (MICWs) with a single-cavity open section in an MFAH were investigated. Tests were conducted on 12 MICWs and obtained the indexes of bearing capacity and ductility under different slenderness ratios from 27 to 93. Within this range, the bearing capacity of the specimens decreased by approximately 7% for every slenderness ratio 7.32 increase. A refined finite element model (FEM) was established and verified against the corresponding experimental results, which were in good agreement. Furthermore, FEM was used for an extensive parametric study that consisted of specimens with different initial bending values, initial eccentric values, cavity thickness values, and column lengths. The ultimate strengths were employed to evaluate the current design methods. It is demonstrated that the European code (Eurocode 9) and Chinese code (GB 50429) underestimate the bearing capacity by approximately 20%–30%, whereas the American code (AA-2015), Australian code (AS/NZS-1997) and the Direct Strength Method (DSM) overestimate the bearing capacity, which is unconservative. Based on Perry's formula, an equation for calculating the axial compressive bearing capacity of MICWs was proposed. The theoretical design method was verified by comparing the theoretical results with the experimental and numerical results, and the proposed method was found to be accurate and conservative to some extent.

Preparation a highly sensitive and flexible textile supercapacitor based on lignin hydrogel and polyaniline@carbon cloth composites

The flexible textures are prominent candidates for wearable devices with energy storage and high sensitive sensor properties. This paper proposed a method for preparing a flexible textile supercapacitor with the displacement sensor property, which consisted of lignin hydrogel as the semi-solid electrolyte and polyaniline@carbon cloth as the flexible electrode. A series of lignin hydrogels with different cross-linking degrees, which were employed as the semi-solid electrolyte, were prepared by using kraft lignin and polyethylene glycol diglycidyl ether as a crosslinking agent. It is shown that the compressive strength (0.196 MPa) and water retention capacity (92.9 %) of the lignin-based hydrogel could be greatly improved by adjusting the cross-linking degree of the hydrogel. Furthermore, the textile supercapacitor was assembled by using polyaniline@carbon cloth as the flexible electrode with lignin hydrogel. The electrochemical tests show that the hydrogel supercapacitor has good ionic conductivity and rate capability, maintaining a high capacitance (200.3 F·g−1) and coulomb efficiency after 6000 cycles. Meanwhile, it shows good sensitivity and stability in both pressure and bending sensing tests, and has the potential to become a new generation of flexible materials.

Axial compressive behavior of corroded double-steel-plate composite shear wall with binding bars

Steel structure is susceptible to corrosion, and corrosion will seriously affect its own load-bearing capacity and service life. In this paper, the axial compressive behavior of double-steel-plate composite shear wall (DSCW) with binding bars under different corrosion degrees is experimentally studied. The typical failure modes include the steel plate local buckling, binding bars fracture, concrete crushing, and steel plate weld tearing. The increase of corrosion rate has unfavorable influence on the axial compressive bearing capacity, initial stiffness, and ductility of DSCW. Finite element (FE) models are established to further investigate the axial compressive behavior of DSCW. It is concluded that the concrete and steel plate strength grade, the concrete section area, the steel plate thickness, and the binding bars diameter and spacing significantly affect the axial compressive bearing capacity of DSCW. A formula calculating the axial compressive bearing capacity of corroded DSCW with binding bars is proposed. The formula agrees well with the test results and can provide a reference for the engineering application.

Machine learning models for predicting the axial compression capacity of cold‑formed steel elliptical hollow section columns

Machine learning models for predicting the axial compression capacity of cold‑formed steel elliptical hollow section columns