Reinforcement Configurations Research Articles

Predicting the moment resistance and localization strain of reinforced UHPFRC cross-sections subjected to bending

The determination of the ultimate moment resistance of UHPFRC sections additionally reinforced with reinforcing steel or prestressing requires addressing the failure mode “crack localization”. At this failure mode, the growth of a single localized crack initiates the failure of the structural member. The onset of crack localization generally coincides with the decrease of fiber contribution in the flexural crack. In order to predict both the ultimate moment resistance and the localization strain, a verification method is derived based on mechanical principles. The contribution of UHPFRC in tension to the moment resistance is estimated by a stress block which is calibrated by means of experimental stress-crack opening relations. The stress block is applied to the tension zone of the section and is limited to a specific crack width being correlated with the beginning decrease of the fiber contribution in the flexural crack. To convert the crack width into strain a structural characteristic length is defined accounting for both the size effect and the reinforcement configuration. The proposed method is checked against experimental results and by parameter studies. The comparison with the results obtained by applying the stress–strain relation defined in NF P18-710 shows differences in the predicted localization strain which are predominantly attributed to the fact that the structural characteristic length defined in NF P18-710 does not account for the reinforcement configuration.

A simplified analysis of a configuration of geosynthetic reinforcement in GRPS embankments

Geosynthetic-reinforced and pile-supported (GRPS) embankments are increasingly used in recent years to reduce the differential settlement and increase the bearing capacity of the embankments. A new theoretical model is proposed to calculate the tensile force distribution and cross-sectional configuration of the geosynthetic reinforcement used in the Geosynthetic-reinforced and flexible pile-supported GRRPS and Geosynthetic-reinforced and rigid pile-supported GRFPS embankments. The accuracy of the proposed methods is verified by the results from laboratory model tests, centrifuge model tests and theoretical models in the literature. It is found that the tensile forces along the geosynthetic are distributed unevenly both in GRRPS and GRFPS embankments with the maximum and minimum magnitudes located at the edge and centre of the pile cap, respectively. The soil arching effect contributes more to the bearing capacity of the GRPS embankment than the membrane effect. It is found through the analyses of the centrifuge and model tests data that the soil arching effect contributes 65–75% of the total load transfer efficiency.

Investigation of RC Buildings after 6 February 2023, Kahramanmaraş, Türkiye Earthquakes

Two major earthquakes struck Pazarcık and Elbistan, towns in Kahramanmaraş, Türkiye, on 6 February 2023, approximately 9 h apart. The first earthquake, recorded at 04:17 local time, had a Mw = 7.7, with a focal depth of 8.6 km. At 13:24 local time, a second earthquake occurred with Mw = 7.6 at a focal depth of 7 km, approximately 90 km north of the first one. A total of 11 provinces were severely affected by these earthquakes. As of 15 April 2023, they caused close to 51,000 deaths and almost 215,000 completely destroyed/severely damaged buildings. At some locations, the largest horizontal peak ground acceleration (PGA) values of the first and second earthquakes exceeded the code-generated PGAs by almost 3 and 1.75 times, respectively. A technical team visited these areas within 15 h of the first earthquake. The purpose of this article is to present their observations, findings, and the characteristics of the two earthquakes, with comprehensive site survey results supported by photographs. This study concludes that most of the collapsed and severely/moderately damaged buildings in the region were built between 1975 and 2000, when site inspections were rare or non-existent. In addition to the high PGAs recorded in these earthquakes, it was verified that the design and construction of these buildings did not fully comply with the earthquake codes valid at the time. The collapsed buildings and their damage patterns confirm inadequate development length, violation of bending stirrup ends at 135°, deficiencies in construction materials and reinforcement configuration, noncompliance with confinement zones, violation of the strong beam-stronger column analogy, and issues related to building inspection. Based on the extent of the damage, it is strongly recommended that the structural performance inspection of all other buildings located near major fault lines, specifically those constructed between 1975 and 2000, should be completed. Since these earthquakes generated much higher PGAs, which is believed to be one of the main reasons for the extensive damage, a re-evaluation of all other PGAs along major fault lines is also recommended.

Loss-free tensile ductility of dual-structure titanium composites via an interdiffusion and self-organization strategy

The deformation-coordination ability between ductile metal and brittle dispersive ceramic particles is poor, which means that an improvement in strength will inevitably sacrifice ductility in dispersion-strengthened metallic materials. Here, we present an inspired strategy for developing dual-structure-based titanium matrix composites (TMCs) that achieve 12.0% elongation comparable to the matrix Ti6Al4V alloys and enhanced strength compared to homostructure composites. The proposed dual-structure comprises a primary structure, namely, a TiB whisker-rich region engendered fine grain Ti6Al4V matrix with a three-dimensional micropellet architecture (3D-MPA), and an overall structure consisting of evenly distributed 3D-MPA "reinforcements" and a TiBw-lean titanium matrix. The dual structure presents a spatially heterogeneous grain distribution with 5.8 μm fine grains and 42.3 μm coarse grains, which exhibits excellent hetero-deformation-induced (HDI) hardening and achieves a 5.8% ductility. Interestingly, the 3D-MPA "reinforcements" show 11.1% isotropic deformability and 66% dislocation storage, which endows the TMCs with good strength and loss-free ductility. Our enlightening method uses an interdiffusion and self-organization strategy based on powder metallurgy to enable metal matrix composites with the heterostructure of the matrix and the configuration of reinforcement to address the strength-ductility trade-off dilemma.

Enhancing the mechanical and electrical conductivity of copper matrix composites through grafting carbonized polymer dots (CPD) onto carbon nanotube surfaces

Tailoring the structural design of reinforcement is an effective strategy to attain the homogeneous dispersion and robust interface bonding in carbon nanotubes reinforced copper (CNTs/Cu) composites. Herein, a novel zero-dimensional carbonized polymer dots (CPD) was synthesized and grafted onto the CNTs surfaces via a typical one-step hydrothermal method. The resultant reinforcement, CPD@CNTs, exhibited good dispersibility due to the abundant polar functional groups on CPD. Furthermore, the interface adhesion was also ameliorated by means of the in-situ formed Cu2O transient phase. The CPD@CNTs/Cu composite shows outstanding mechanical performances, the yield strength and tensile strength had increased to 269 MPa and 308 MPa, while maintained excellent ductility (43 %). Moreover, the electrical conductivity of the composite remains at a high level of 95.3 %IACS. Our findings suggest that adjusting the structural configuration of reinforcement is a feasible approach to optimize dispersion and interfacial structure.

Projectile Impact on Plain and Reinforced Concrete Slabs

Reinforced concrete is a material frequently used in protective structures and infrastructure exposed to extreme loading. In this study, the ballistic perforation resistance of 100 mm thick plain and reinforced concrete slabs impacted by 20 mm ogive-nose steel projectiles was investigated both experimentally and numerically. Two different reinforcement configurations were used to investigate the effect of rebar diameter and spacing. Concrete with nominal unconfined compressive strength of 75 MPa was used to cast material test specimens and slabs. Ballistic impact tests were performed in a compressed gas gun facility. The mechanical properties of the concrete were found using standardised tests and two-dimensional digital image correlation, and the constitutive relation was described by a modified version of the Holmquist-Johnson-Cook model. Finite element models in LS-DYNA reproduced the projectile residual velocity in good agreement with the experimental results. The primary objective of the study was thus to validate a rather simple constitutive relation intended for large scale numerical simulations of concrete structures exposed to ballistic impact loading, while a secondary objective was to investigate the effect of reinforcement on the ballistic perforation resistance of concrete slabs both experimentally and numerically since the literature is somewhat inconsistent on this matter.

Nonlinear analysis of interior and exterior beam-column connections under reversed cyclic loading

This paper presents a case study into the application of nonlinear finite element for the analysis of interior and exterior beam-column joints under reversed cyclic loading. Three beam-column joints, with different reinforcement configurations and test conditions, were considered to assess the accuracy of the currently available constitutive models in predicting the full hysteretic response of beam-column joints under reversed cyclic loading. To this end, the three beam-column joints were modelled in ATENA-GiD which implements nonlinear constitutive models for steel and concrete, the latter of which are formulated within the context of crack-band and crush-band approaches. In this paper, the default constitutive models in the program were employed to evaluate the accuracy of the existing modelling and analysis procedures. From the series of results presented, it is shown that the existing constitutive models are capable of predicting various aspects of the joint behaviour under reversed cyclic loading with good accuracy. This includes the peak load capacity, degrees of pinching and strength degradation, strength and stiffness degradation, unloading and reloading stiffnesses, crack patterns and failure modes.

Oštećenja AB zgrada u İzmiru nakon potresa u Egejskom moru 30. listopada 2020.

An earthquake with a magnitude of Mw = 6.6 and a depth of approximately 16.5 km occurred on 30 October 2020 off the cost of Samos, a Greek island 35 km southwest of Seferihisar, a town in İzmir. The earthquake caused several collapses and severe structural damage in approximately 6,000 buildings, specifically in the Bayraklı District in İzmir Bay. This paper presents the observations and findings of a technical team that visited the earthquake-affected areas immediately after an earthquake. Eleven partially or fully collapsed buildings and several severely damaged reinforced concrete buildings were investigated. Based on the site observations, we observed that almost all of the collapsed or severely damaged reinforced concrete buildings in the region were built between 1975 and 2000. Site observations also confirmed that the construction of these collapsed or damaged buildings did not conform to the requirements outlined in the Turkish Earthquake Codes used at the time. The failures and severe damage to buildings in earthquake-affected areas are primarily related to inadequate reinforcement configuration, poor material quality, the absence of geotechnical studies, and framing problems related to their lateral load-carrying systems. Therefore, it is recommended that all the buildings located in and around İzmir Bay, particularly those built between 1975 and 2000, be structurally evaluated to prevent any further loss of life and property during future earthquakes.

Experiment study on reactive powder concrete beams using spirals reinforcement under torsion

This paper investigates the torsional behavior of reactive powder concrete (RPC) beams using spiral reinforcement. The influences of parameters, including different spiral reinforcement configuration, spiral reinforcement ratio, and the steel fiber content on the torsional performance of the nine RPC beams, were investigated and discussed. The experimental results showed that the failure mode, ultimate torque, torsional stiffness, and energy dissipation of the RPC beams were not affected by longitudinal reinforcement alone, but it improved the ductility. Compared to commonly used stirrups, the locked spiral reinforcement exhibits more torsional ductility, stiffness, and ultimate torque of the RPC beams. But the torsional ductility, stiffness, and ultimate torque decreased when the spiral reinforcement was unlocked. The cracking torque and pre-cracking torsional stiffness of beams were less affected by the locking and unlocking of spiral reinforcement. Greater steel fiber content and spiral reinforcement ratio resulted in higher torsional ductility, torsional stiffness, energy dissipation and ultimate torque of the locked spiral reinforcement reinforced beams. The pre-yielding torsional stiffness and plastic dissipation capacity were strongly influenced by spiral reinforcement states and spiral reinforcement ratio. The pre-cracking torsional stiffness and energy dissipation of RPC beam were determined by the steel fiber content. Considering the torsional contribution of steel fiber and concrete tensile strength, a new formula for calculating the ultimate torque of RPC beam was proposed, and the calculated value was closer to the experimental value.

Feasibility of improving shear performance of RC pile caps using various internal reinforcement configurations: Tests and finite element modelling

The loads from columns and bridge piers are transferred to the pile foundation by reinforced concrete (RC) pile caps, which are important structural components whose behavior is significantly affected by the internal reinforcement configuration. Therefore, the current study experimentally investigates the shear response of RC pile caps by testing nine specimens have identical dimensions and various reinforcement configurations. The experimental matrix is designed to study (i) the influence of using a closed transversal reinforcement along with the presence of an upper reinforcement only or an upper and side reinforcement together. (ii) Behavior of RC pile caps internally reinforced with various closed-side bars’ area and (iii) the impact of the interaction between the longitudinal reinforcement of the piles and the column in the presence of upper reinforcement only or side closed bars solely. RC pile cap specimen internally reinforced with closed transversal reinforcement with upper reinforcement and 12 mm-diameter closed side bars can be considered the optimal reinforcement form due to the fact that this specimen achieved the highest ultimate load and toughness of 1286 kN and 1089 kN.mm, respectively. Moreover, the current research involves the development of a three-dimensional (3D) non-linear finite element model to evaluate the response of RC pile caps while taking into account concrete's tensile strength and softening behavior in either tension or compression. Results of the numerical model well agreed with the experimental data. Additionally, a parametric study is conducted using the verified model to examine the impact of utilizing bent bars positioned perpendicular to the shear crack's direction on the ultimate load, failure pattern, and toughness of the RC pile caps.

Flexural and compressive performance of BFRP-reinforced geopolymer sea-sand concrete beams and columns: Experimental and analytical investigation

The combination of geopolymer sea-sand concrete (GSSC) and basalt fiber reinforced polymer (BFRP) reinforcement has the potential to optimally exploit the advantages of both materials, resulting in superior structural durability and environmental friendliness. The resulting structure is called a BFRP-reinforced GSSC structure, which has broad application prospects in marine engineering construction. This paper presents a recent experimental and analytical investigation into the flexural and compressive performance of BFRP-reinforced GSSC structures to verify the expected benefits of such a material combination. In particular, a type of GSSC that uses MgO as an expansion agent to reduce concrete shrinkage was used in this study. The results of four-point bending tests on nine rectangular beams, where longitudinal reinforcement ratios and reinforcement types were key parameters, and monotonic axial compression tests on seven columns, where concrete types and transverse reinforcement ratios were key parameters, are reported in this paper. The test results initially confirmed the advantages of using GSSC in combination with BFRP reinforcement and showed that: (1) the ultimate carrying capacity of BFRP-reinforced GSSC beams and columns was higher than that of conventional steel-reinforced counterparts for the same reinforcement configurations; (2) the flexural and compressive capacity of BFRP-reinforced concrete beams and columns could be enhanced by an appropriate increase in reinforcement ratio and the addition of expansion agents. Finally, this paper presents design equations for the flexural and compressive capacity of BFRP-reinforced GSSC structures.

Experimental Study on the Seismic Mechanism of Full-scale Specimens of Superimposed Slab Shear Walls with Innovative Construction Details

The seismic performance of precast reinforced concrete structures has long been a source of concern that impedes their use in seismic regions and high-rise buildings. To further optimize the reinforcement configuration and enhance the seismic performance of the superimposed slab shear wall structures, this research proposed a superimposed slab shear wall with innovative construction details. Five innovative superimposed slab shear walls and one cast-in-place concrete shear wall were designed and tested under low cycle lateral load. The effect of axial compression was considered during tests and analyses as well. In this paper, the seismic performance, including failure mode, hysteretic behavior, load-bearing capacity, lateral stiffness degradation, energy dissipation, and seismic ductility was investigated and analyzed. The experimental results showed that five innovative superimposed slab shear walls and one cast-in-place concrete shear wall exhibited a similar failure mode of flexural-shear failure, and a large area of concrete was damaged and crushed at the shear wall corner. However, the area of crushing concrete in the cast-in-place concrete shear wall was relatively small. And the area of crushing concrete in the superimposed slab shear walls increased with the axial compression ratio. For the superimposed slab shear walls, the development of concrete cracks decreased gradually with the enlargement in the axial compression ratio, while the length of the cracks increased in this respect. The results indicated that innovative superimposed slab shear walls had a higher strength capacity and lower lateral-resistant stiffness than the cast-in-place concrete shear wall. With the enlargement in the axial compression ratio, the peak strength capacity of the superimposed slab shear wall increased obviously, while it degraded rapidly after the peak load. It is suggested that the contribution of axial compression to the shear resist capacity of the inclined section should not be considered in practical design. Meanwhile, the ductility coefficients of the six specimens were larger than 2.2, which was in accordance with the seismic requirements. This investigation could provide effective experimental data for future structural seismic performance evaluations and applications of precast superimposed slab shear wall structures.

Quasi-static cyclic behavior of precast high-strength concrete tunnel segments reinforced with GFRP bars

The cyclic behavior of fiber-reinforced polymers (FRP) reinforced precast concrete tunnel lining (PCTL) segments under quasi-static cyclic flexural loading has not yet been experimentally tested and reported on in the literature. This study investigated the cyclic behavior of glass-FRP (GFPR) reinforced precast high-strength concrete (HSC) tunnel lining segments. Full-scale segments measuring 3100 × 1500 × 250 mm were tested under quasi-static cyclic flexural loading. Two cycles of loading and unloading were applied at 1.25%, 2.5%, 5%, 10%, 25%, 50%, and 75% of the maximum displacement obtained from the static testing results, followed by a single cycle up to failure. The test parameters included concrete compressive strength, longitudinal reinforcement ratio and transverse reinforcement configuration (closed ties versus double U-shaped ties). The experimental findings of this study revealed that the GFRP-reinforced HSC PCTL segments exhibited stable hysteretic response until failure. In addition, the test results show that the GFRP-reinforced HSC PCTL segments were able to achieve adequate ductility indexes as well as deformability limits. A theoretical prediction according to the North American codes and design guidelines, including flexural capacities, cracking moment, and crack width, was made and the results compared to the experimental results. This research illustrates the advantages of using HSC for PCTL segments internally reinforced with GFRP bars under quasi-static cyclic flexural conditions.

Influence of aperture size on the performance of square footing resting on rattan reinforced sand

ABSTRACT Rattan fibre as a reinforcement material can be a promising candidate for fabricating mattresses that improves the bearing capacity and settlement reduction of sand. Apart from observing the potential of rattan mats in reinforcing the sand beds, an attempt is made to understand the role of apertures with varying dimensions in enhancing the load bearing performance of sand. A series of plate load tests were performed to study the effect of the depth of top layer reinforcement, width, aperture size of rattan mats and number of reinforcement layers. After comparing the test results of various aperture sized mats, openly woven rattan mats performed superior to closely woven mats. The incorporation of rattan mats under the most effective reinforcement configuration has enhanced the bearing strength improvement factor and settlement reduction factor to 7.1 and 0.85, respectively, for closely woven rattan mats and about 8.16 and 0.94 for openly woven rattan mats with optimum aperture sizes.

Experimental and analytical study on structural performance of reinforced lightweight geopolymer composites panels

Various lightweight panels such as autoclaved aerated concrete (AAC) panels have been widely used in the prefabricated construction. With the growing demand for eco-friendly building materials, geopolymer as cementitious material has been extensively studied. A novel ambient-cured lightweight geopolymer composite (LGC) with expanded polystyrene (EPS) was recently developed by the authors and demonstrated sound static and dynamic mechanical properties. In this study, a new lightweight reinforced panel made of LGC is proposed for prefabricated structures. Five full-scale panels, including one AAC panel and four LGC panels with different configurations, were prepared and tested under four-point bending to investigate the effects of panel thickness and reinforcement configuration on the structural performance. The test results showed that the LGC panels demonstrated better structural performance, with the characteristic ultimate bending capacity 57%-110% higher than that of the corresponding AAC panel. An analytical study was also conducted, and empirical formulae were proposed to predict the ultimate bending capacity of LGC panels.

Centrifuge Model Tests and Numerical Analysis of Uplift Capacity of Strip Anchors in Geogrid-Reinforced Sand

Anchor-type foundations are one of the foundation types used in structures subject to tensile forces. These anchors are generally designed according to the weight of the soil on them depending on the depth they are buried at and the frictional resistance obtained from the failure surfaces during failure. One method of increasing the uplift capacity of the foundation without increasing the burial depth is the use of geogrid material. In this study, the uplift capacities of strip anchor plates at different embedment depths were investigated by considering the geogrid effect placed in different combinations. The aim of the study is to investigate whether a more economical solution can be obtained by using geogrid without increasing the embedment depth of the anchor plate. Experiments were carried out using centrifugal experimental setup, which gives values closer to the real results. The tests were performed on sand of two different densities for anchor burial depths H/B = 2 and H/B = 5. According to the results, the uplift capacity is significantly improved when geogrid is used. As the reinforcement configuration, the use of a single geogrid layer placed just above the anchor plate with an inclination angle of 45 degrees gave more effective results than using the geogrid horizontally and vertically. In the study, up to 98% increases in uplift capacity were obtained with reinforcement. In addition, the prototype model was analyzed with a numerical program based on the finite element method, and the results were compared with the experimental results. As a result of the comparison, it was observed that the experimental and numerical results were compatible with each other. Suggestions for practice are presented using the results obtained.

Mechanical Properties of GFRP Bolts and Its Application in Tunnel Face Reinforcement

As a new type of pre-reinforcement material for tunnel faces, glass fiber-reinforced polymer (GFRP) bolts can effectively and safely improve the stability of tunnel faces in soft surrounding rocks and speed up excavation. Therefore, in this paper, systematic research is carried out on the bond strength of GFRP bolts in tunnel faces and their relative pre-reinforcement parameters. Firstly, the effects of rebar diameter, anchorage length, and mortar strength on the bonding properties of GFRP bars were studied by indoor pull-out tests. The bond strength-slip curves under different working conditions were obtained, and the curves showed that the ultimate bond strength between GFRP bars and mortar was negatively correlated with the diameter of GFRP bars but positively correlated with the strength of the mortar. In addition, the increase in anchorage length led to a reduction in bonding strength. Secondly, inverse analysis was used to analyse the mechanical parameters of the bond performance of the anchor bars by the finite difference software FLAC3D, and the results indicated that 1/5 of the compressive strength of the GFRP bar grouting body can be taken as the ultimate bond strength to calculate the cohesive strength of the grout. Additionally, the formula of GFRP bar grouting body stiffness was revised. Finally, based on the results of laboratory tests and the inverse analysis, the numerical simulation analysis results showed that the optimal reinforcement configuration for a shallow buried tunnel face surrounded by weak rock is to use GFRP bars with a length of 17 m arranged in the center circle of the tunnel face with a reasonable reinforcement density of 1.0 bolt/m2. The calculation formula of the stiffness and cohesion strength of the GFRP bar grouting body and the reinforcement scheme proposed in this paper can provide a reference for the construction of shallowly buried rock tunnels in soft surrounding rock.

Time-dependent study of load transfer mechanism in geocell reinforced soil bed

Geocell-reinforced embankments are commonly subject to rail or road traffic which comprises repetitive loads. However, the existing equations for the analysis and design of geocell-reinforced systems are based on performance under static loads. Hence, it is imperative to study the performance of geocell-reinforced embankments under repetitive loads. The study addresses the shortage of time-dependent studies on geocell-reinforced systems by analyzing the performance of geocell-reinforced embankments under repetitive loads over time. The actual curvature of honeycomb-shaped pockets is carefully modeled for accurate analysis of the load transfer mechanism of geocell-reinforced soil. The study analyses two different geocell configurations that are conventionally adopted in practice. In the first case, the geocell platform is placed at the embankment base and restrained within the toe of the embankment. In the second case, the platform is extended on both sides to serve as a working platform. The study aims to assess the effect of the configuration of geocell reinforcement under different types of loading. The time-dependent response of the embankment over the geocell platform is then analyzed for static and repetitive loads to assess the performance of geocell-supported embankments under different loading applications. The lateral deformation at the toe, stress on the subgrade, and heave characteristics are analyzed for time. It is observed that the presence of geocell at the embankment base not only reduces the stress transferred to the subgrade but also mitigates differential settlement over time. The difference in reinforcing effect under static and repetitive loads is notable in the case of surface heave reduction. Both configurations reduce stress on the subgrade. However, for a significant reduction in surface heave, it is recommended to place the geocell mat as a working platform extending beyond the embankment toe on both sides.

Seismic performance of resilient recycled aggregate piloti-type structure employing ultra-high strength bars

A resilient recycled aggregate piloti-type brick masonry structure equipped with ultra-high strength bars (UHSB) in the pilotis and shear walls was proposed. Quasi-static test and finite element analysis based OpenSees were conducted to study its seismic performance. The main parameters include different steel bar categories, reinforcement configurations, storey stiffness ratios and shear wall distributed reinforcement ratios. The results revealed that both the recycled aggregate concrete (RAC) frame-shear wall structure at the first storey and the upper recycled brick masonry structure showed satisfactory deformation performance and stable load-carrying capacity. The frame-shear wall structure at the weak first storey is prone to suffer from shear failure of the shear wall under the relatively large drift due to the larger proportion of shear deformation. The plastic damage of the pilotis and shear wall reinforced with UHSB was obviously reduced. The arrangement of diagonal UHSB in the shear wall can significantly improve the shear resistance and prevent the premature shear failure of the shear wall, and further enhance the resilience and seismic performance of the bottom-storey structure. The proposed resilient frame-shear wall structure of bottom storey presented excellent repairable performance. The innovative piloti-type brick masonry structure with resilient bottom storey can give full play to the resilience and seismic performance of its bottom-storey frame-shear wall structure even with a relatively higher storey stiffness ratio.

Mechanical properties of steel reinforced coral aggregate concrete column under uniaxial compression

The production of coral aggregate concrete (CAC) from coral debris effectively addresses the lack of building materials in island construction. Due to the low compressive strength and visible brittleness of CAC, steel reinforcement with anti-rust treatment is adopted to improve the mechanical properties of CAC. This paper presents an experimental study on the mechanical behavior of 45 anti-rust coated steel reinforced coral aggregate concrete (RCAC) columns under uniaxial compression, designed with the consideration of concrete strength and configurations of the transverse reinforcement. The test results show that the volumetric ratio of lateral confinement can improve the compressive strength and ductility of RCAC effectively. The strengthening effect of diamond-shaped composite and spiral hoop is higher, while that of rectangular hoop is slightly weaker. The increase of concrete strength has a significant positive effect on the peak stress, but not on the peak strain. Based on the experiments, the formulae for the peak stress and peak strain of RCAC are given, and the constitutive model of RCAC is proposed. Moreover, the calculation method of the theoretical bearing capacity is arrived at, and the predicted values with a specific safety reserve are close to the measured values.