Coral Aggregate Research Articles

Bond of Seawater Scoria Aggregate Concrete to Stainless Reinforcement

This study investigates the bond between seawater scoria aggregate concrete (SSAC) and stainless reinforcement (SR) through a series of pull-out tests. A total of 39 specimens, considering five experimental parameters—concrete type (SSAC, ordinary concrete (OC) and seawater coral aggregate concrete (SCAC)), reinforcement type (SR, ordinary reinforcement (OR)), bond length (3, 5 and 8 times bar diameter), concrete strength (C25 and C30) and concrete cover thickness (42 and 67 mm)—were prepared. The typical bond properties (failure pattern, bond strength, bond-slip curves and bond stress distribution, etc.) of seawater scoria aggregate concrete-stainless reinforcement (SSAC-SR) specimen were systematically studied. Generally, the failure pattern changed with the concrete type used, and the failure surface of SSAC specimen was different from that of OC specimen. SSAC enhanced the bond strength of specimen, while its effect on the deformation of SSAC-SR was negative. On average, the peak slip of SSAC specimens was 20% lower while the bond strength was 6.7% higher compared to OC specimens under the similar conditions. The effects of variables on the bond strength of SSAC–SR in increasing order are concrete type, bond length, concrete strength and cover thickness. The bond-slip curve of SSAC-SR specimen consisted of micro-slipping, slipping and declining stages. It can be obtained that SSAC reduced the curve curvature of bond-slip, and the decline of curve became steep after adopting SR. The typical distribution of bond stress along bond length changed with the types of concrete and reinforcement used. Finally, a specific expression of the bond stress-slip curve considering the effects of various variables was established, which could provide a basis for the practical application of reinforced SSAC.

Bond-Slip Behavior for Corroded Cr Alloy Reinforced Coral Aggregate Concrete Based on Experimental and Hybrid Machine Learning

Bond-Slip Behavior for Corroded Cr Alloy Reinforced Coral Aggregate Concrete Based on Experimental and Hybrid Machine Learning

Mix design optimization of seawater sea sand coral aggregate concrete

Mix design optimization of seawater sea sand coral aggregate concrete

Hardening Mechanism of Coral Aggregates in Cement-Based Systems

In terms of the infrastructure construction near coral reefs, native coral aggregates have been widely implemented as alternative efficient building materials to prepare the "coral concrete". This study focused on the mechanical properties and hardening mechanism of coral particles under cement-based systems. Firstly, coral particles were divided into two categories: coral biological debris particles (calcium sand) and coral parent rock particles (limestone). Subsequently, several elementary laboratory tests were conducted to compare the physical and chemical properties of the samples. The results demonstrate that the specific surface area and open pores of coral particles are bigger than those of quartz sand. Moreover, the water absorption rate of debris and parent rock particles reach 9.9% and 22%, respectively. To further examine the hardening mechanism of coral particles, we carried out particle crushing strength tests, compressive strength tests and nanoindentation tests. Regardless of the tested groups and particle categories, the results show that the wrapped cement slurry universally demonstrated the successful enhancement of crushing strength σ0,d. Particularly, in the size range from 1.18-2.36 mm, wrapped particles of debris and parent rock both reached unusually high σ0,d values: 10.14 MPa and 8.74 MPa, respectively. However, in the size range from 9.5 mm to 16 mm, the σ0,d values of wrapped debris and parent rock reached 4.75 MPa and 3.18 MPa, respectively. According to the nanoindentation tests, the sub-microscopic strength of ITZs was enhanced to more than 1 GPa, which is higher than that of conventional concrete, in terms of the sample with 28-day maintenance. In conclusion, this study has provided a further basis for studying coral concrete material and its hardening mechanism.

Durability of discrete BFRP needle-reinforced seawater sea-sand concrete-filled GFRP tubular columns in the ocean environment

In this paper, a long-term durability test on a new type of seawater sea-sand concrete (SWSSC)-filled glass fiber-reinforced polymer (GFRP) tubular column, which was previously proposed by the authors, was conducted. The adopted inner-filled concrete included seawater sea-sand gravel aggregate concrete (SSGC), discrete basalt fiber reinforced polymer (BFRP) needle-reinforced SSGC (BNSSGC), seawater sea-sand coral aggregate concrete (SSCC), and discrete BFRP needle-reinforced SSCC (BNSSCC). The naked concrete columns and GFRP tube-confined columns were immersed in artificial seawater under ambient temperature for up to 22 months. The variation laws of the axial compressive properties of the short columns were tested and compared, and the performance degradation mechanisms were microscopically analyzed by scanning electron microscopy (SEM). In addition, a long-term prediction model was adopted to predict the degradation of the load-bearing capacity of the environmentally conditioned concrete-filled GFRP tubular columns. The test results showed that for the SWSSC-filled GFRP tubular columns, the strength degradation of the specimens with gravel aggregates was not obvious, while the strength of the columns with coral aggregates all showed a stable degradation trend. Pits and resin shedding were observed on the surfaces of the BFRP needles and GFRP tubes, and fiber/resin debonding was the internal mechanism of the degradation of mechanical properties. The predicted stable axial compression strength retention of the FRP-SSGC columns, FRP-SSCC columns, and FRP-BNSSCC columns was 0.944, 0.917, and 0.823, respectively.

Flexural Behavior of Seawater Sea-Sand Coral Aggregate Concrete Beams Reinforced with FRP Bars

Flexural Behavior of Seawater Sea-Sand Coral Aggregate Concrete Beams Reinforced with FRP Bars

Short-term creep behaviors of seawater sea-sand coral aggregate concrete: An experimental study with Rheological model and neural network

Appropriate utilization of wasted coral aggregates, seawater and sea-sand can effectively resolve the shortage of raw materials for offshore projects and shorten the construction period. However, the low strength and porous nature of coral coarse aggregate will affect the creep properties of seawater sea-sand coral aggregate concrete (SSCAC) under short-term sustained load and this study aimed to investigate the short-term creep behaviors of SSCAC. A total of 72 SSCAC specimens were prepared and subjected to sustained load to analyze the influence of curing age, load duration and applied load level on the short-term creep behaviors of SSCAC; meanwhile, the Rheological model based on the Boltzmann superposition principle and the artificial neural networks (ANN) model were introduced to predict the short-term creep of SSCAC. The experimental results indicated that the creep and hysteretic recovery strain of SSCAC increased with the load duration and applied load level due to its viscoelastic property and the internal micro-damage accumulation, while decreased with the curing ages owing to the cement hydration. Three classical models, ACI209R, B3, GL2000 as well as the present Rheological model, ANN model were compared with the test results. The present models in this study correlated more well with the test results than classical ones. In addition, the creep deformation of SSCAC is 56.1 % and 48.4 % higher than that of ordinary concrete at 3 days curing age and 28 days curing age, respectively. Moreover, the fundamental time-dependent strains of SSCAC could reach its peak within minutes and gradually kept stable during load duration, which implies that the partial hysteretic recoverable deformation gradually transform into unrecoverable deformation with the accumulation of micro-damage in SSCAC. The overall results clearly characterize the short-term creep behaviors of SSCAC and demonstrate that the Rheological model and ANN model can both provide reliable prediction results for the fundamental time-dependent strain of SSCAC.

Mechanical properties and uniaxial constitutive model of fiber‐reinforced coral aggregate concrete

AbstractThis article studied the mechanical properties and constitutive model of fiber‐reinforced coral aggregate concrete (FRCAC). The test results show that basalt fibers, carbon fibers, and polypropylene fibers (BFs, CFs, and PFs) can enhance the cube compressive strength and splitting tensile strength of coral aggregate concrete (CAC), but there are optimum contents. The optimal content of BFs, CFs, and PFs are 0.8%, 1.5%, and 0.3%, respectively. Fibers increase slightly the elastic modulus of FRCAC. The peak stress, peak strain, and ultimate strain of CAC can be improved by fibers, and the improvement effect is CFs, BFs, and PFs in descending order. According to the experimental results, a damage constitutive model suitable for FRCAC was proposed, which can efficiently indicate the stress–strain relationship of FRCAC. The damage parameter in the model can predict the damage evolution process of FRCAC.

Investigation of mechanical strength and permeability characteristics of pervious concrete mixed with coral aggregate and seawater

The availability of the conventional raw materials required to produce pervious concrete on sea islands remote from the mainland is lacking, which could be alleviated by utilizing marine resources. This study aimed to develop seawater coral aggregate pervious concrete (SCAPC) by utilizing coral waste and seawater and assess the potential application of this method to sea islands. The SCAPC specimens were designed with different coral aggregate sizes (2.36–4.75 mm, 4.75–9.5 mm) and aggregate/binder ratios (2, 2.5, 3), and the addition of 10 % of sea sand. The physical properties (hardened density and porosity), mechanical strengths (compressive and splitting tensile strengths), water permeability, and sulfate attack resistance were investigated. The failure surface under mechanical loading and the microtopography between matrix and coral aggregate of SCAPC samples were also characterized. The results showed that the compressive strength and water permeability coefficient of the resulting SCAPCs at 28 days with a porosity ranging from 16.9 % to 33.5 % could reach 6.2–18.5 MPa and 12.9–26.5 mm/s, respectively. This not only satisfied the ACI 522R-recommended values for pervious concrete applicable to pedestrian road areas, but the samples demonstrated excellent permeability. The SCAPC specimens manufactured with aggregate/binder ratios of 2.5 incorporating 10 % sea sand were found to achieve the required balance between compressive strength (11.8–12.5 MPa) and water permeability coefficient (19.6–20.9 mm/s). The failure patterns of the SCAPC samples presented a markedly different complete fracture of coral aggregate point from that of traditional aggregate pervious concrete, ascribing this variation to the characterized fragility of coral aggregate and intensified interfacial adhesion.

Mechanical properties and constitutive model of coral aggregate concrete subjected to dynamic uniaxial and triaxial compression

AbstractThe dynamic compressive mechanical performance of coral aggregate concrete (CAC) has been studied by the servo‐controlled true triaxial testing machine (TAWZ‐5000/3000), the failure modes and the stress–strain curves were obtained under various loading conditions. The effect of strain rates and the constant lateral pressure on the strength, deformation capacity, and failure modes of CAC were analyzed according to the results obtained from the test. The results show that the lateral pressure significantly changes the failure mode while the strain rate only affects the degree. The strength and deformation capacity will improve with the increase of strain rate and lateral pressure, and the lateral pressure diminishes the strain rate effect on mechanical properties. A 5‐parameter empirical dynamic failure criterion was established based on the William‐Warnke criterion. Finally, a 2‐stage dynamic multiaxial compressive constitutive model obeying the Weibull and Lognormal statistical distributions was established, and the model had well‐fitting results with the experimental results.

Durability of BFRP bars embedded in seawater sea sand coral aggregate concrete in simulated seawater environment: Effects of coral coarse aggregate and cement contents

This study evaluates the influences of coral coarse aggregate (CCA) and cement contents on the durability performance of basalt fiber-reinforced polymer (BFRP) bars embedded in seawater sea sand coral aggregate concrete (SSCC). The evaluation is conducted by characterizing the changes in interlaminar shear strength after accelerated exposure in a simulated seawater environment. Accelerated aging tests were conducted under varying exposure durations (60, 120, and 180 days) and temperatures (25, 40, and 55 °C). The 1H low-field nuclear magnetic resonance, Fourier transform infrared spectroscopy, and scanning electron microscopy analyses were conducted to investigate the deterioration mechanisms of embedded BFRP bars. It was found that SSCC-embedded BFRP bars typically have a lower interlaminar shear strength than that of seawater sea sand concrete (SSC)-embedded BFRP bars subjected to the same immersion conditions. This is mainly attributed to the high porosity of CCA, resulting in higher permeability of SSCC than that of SSC. In addition, increasing cement content enhances the initial amount of OH– in SSCC, expands the pitting area of BFRP bars, and maintains OH– concentration better in the exposure tests, accelerating the interlaminar shear strength deterioration of BFRP bars. Microstructure analysis clearly reveals that the deterioration of embedded BFRP bars is mainly caused by resin hydrolysis, fiber-resin interface debonding, and fiber damage after corrosion. Based on the Arrhenius relationship, accelerated aging test results were utilized to predict the service life of SSCC-embedded BFRP bars under the real service condition. The findings of this study are valuable for the application of BFRP bars reinforced SSCC structures under marine environments and provide some insights into improving the long-term performance of SSCC-embedded BFRP bars, i.e., modifying the CCA to minimize the permeability of SSCC and producing low-alkalinity SSCC.

Prediction of dynamic mechanical behaviors of coral concrete under different corrosive environments and its enhancement mechanism

The marine structures are usually exposed to dynamic loadings within short periods and chemical attacks, resulting in severe dynamical damage or failure to concrete structures. The study of the time-dependent changes in the dynamic mechanical behavior of coral concrete under different corrosive environments and low-frequency waves is limited. For the safety and reliable use of coral concrete in the marine environment, different corrosion environments (chloride ions, sulfate ions, and mixed chloride-sulfate ions) and low-frequency waves (0.5–2.0 Hz) were designed to evaluate the dynamic properties of concrete. A model considering the effect of corroded age is formulated to predict the damping capacity of coral concrete. Testing results indicate that sulfate attack shows the most significant effect to influence the dynamic behaviors of coral concrete, while the effect of chloride ion penetration is negligible. The loss factor of coral concrete under corroded environments increases by 59.5% compared with ordinary concrete, even though the loss modulus and storage modulus of coral concrete reduce by 38.5% and 51.8%. It was attributed to coral concrete showing a low ability to resist sulfate attack, resulting in more cracks and pores in the matrix. Coral aggregate with high porosity and interconnected pores in coral concrete works like a cushion to dissipate more external energy. The proposed prediction model (R2 = 0.89) can accurately describe the relationship between erosion age and damping capacity in different corrosion environments, which can guide the application of coral concrete in marine and vibration environments.

Evolution law of crack propagation and crack mode in coral aggregate concrete under compression: Experimental study and 3D mesoscopic analysis

Coral aggregate concrete (CAC) is one of the typical quasi-brittle materials, which is of great significance to explore the damage process of CAC under load from the perspective of fracture mechanics. Therefore, the Cohesive Zone Model (CZM) was introduced to simulate the physical mechanism of crack propagation in CAC materials at the mesoscale adopting the discrete crack method. The main work included test and simulation parts. The tests included CT scanning and mechanical tests, which were used to calibrate the model parameters of CZM and verify the rationality of the meso-mechanical model. Numerical simulation was used to reveal the internal damage and fracture mechanism of CAC. According to the defined damage variables, it was found that the crack growth rate inside the CAC material evolves regularly with the axial strain during compression failure. The crack of CAC with higher strength grade showed oblique sliding shear failure and was more likely to form fracture surfaces, and the aggregate damage was more significant. The revealing of the cracking modes in each strain stage of CAC provides a theoretical basis for guiding the corresponding crack prevention measures. For example, in the stage of significant shear failure, targeted improvement of shear strength and toughness will bring more significant gains.

Physical and mechanical properties of coral aggregates in the South China Sea

Coral aggregate (CA) is a type of marine resource with rich storage capacity and complex physical characteristics, and it is increasingly recognized as an important island engineering material. For the regional variability of CA in the South China Sea, the physical and mechanical properties of different CAs were experimentally studied in this paper. Using the X-ray Computed Tomography technique, the pore characteristics of CA were quantitatively studied in term of the pore shape, size, sphericity, number, volume, etc. Additionally, the uniaxial compressive properties of cylinder CA samples were investigated in term of the failure patterns, stress-strain curves, elastic modulus, strength, and toughness. Results indicate that different CA samples contain a considerable amount of pores with different shapes that are closely related to the coral growth environment. It was found that content of the millimeter-sized pores with a diameter of 0.5∼1 mm is the highest, while the content of the centimeter-sized pores with a diameter greater than 1 cm is the lowest. The porosity of light and heavy CA was determined as 1.37%–22.55% and 3.72%–22.64%, respectively. Splitting failure is the main form of failure to CA under uniaxial compression loading. While the compressive toughness of CA could be effectively improved by the surface-filling method treatment using coral mortar. According to the present results and the existing data, a series of regression equations concerning the physical-mechanical properties of CA were established, which has significant values for the study and application of CA in the South China Sea.

Study on the dense structure and properties of cement-stabilized coral aggregates

The performance of cement stabilized coral aggregates semi-rigid base of pavement with coral reef limestone fragments and biological debris as the main materials is essential in the current reef engineering constructions. The performance of inorganic mixtures such as cement-stabilized coral aggregates mainly depends on the packing state of aggregates and the interfacial bonding among each component. Via digital image analysis theory, a simulation model of the dense packing of particles method was established, considering the influence of arbitrary particles shape distribution, upper limit of particles size, and aggregates gradation. The influencing mechanism of different factors on the packing state was revealed. It was found that the dense packing of coral aggregates is a strong suspension dense structure which did not form the skeleton structure. The strengthening mechanism of the coral particle-coated cement slurry was studied through the experimental analysis of the pore structure of coral rocks and debris particles and the crushing strength of particle-coated cement slurry, combined with the microhardness test of the cement- coral particle interface and the analysis of hydration products. The physicochemical excitation mechanism of hydration products densification，“physical interlocking” and “micro pump” effect at the interface of the cement-coral particle was revealed. Furthermore, based on the macroscopic mechanical properties of cement stabilized coral aggregates, the optimal design ratio of coral aggregates with upper limit particle size of 53mm, fine aggregates content of 45% and cement content of 8% was proposed. The findings of this study can provide a reference for the design and application of cement stabilized coral aggregates semi-rigid pavement base.

Basalt FRP-confined slag-based alkali-activated seawater coral aggregate concrete: Concept and axial stress-strain behavior

This paper presented an experimental investigation on the axial stress–strain behavior of cement-based seawater coral aggregate concrete (CAC) and slag-based alkali-activated seawater coral aggregate concrete (AACAC) confined by basalt fiber‐reinforced polymer (BFRP) sheet, with different BFRP confinement stiffnesses (i.e., 0, 1, 2, 4, and 6 plies) being considered. The experimental results indicated that the FRP confinement was an effective method in enhancing the loading capacity and deformation of cylinder specimens. As the FRP jacket confinement (layer) increased, the slope of the axial stress–strain curves at the ascending branch, axial compressive strength (fcc), and ultimate axial strain (εcc) corresponding to fcc of BFRP-confined CAC and AACAC were gradually enhanced. Compared with the un-confined specimens, the axial compressive strength and ultimate axial strain of the CAC specimens with 6-layer FRP confinement increased by 1.94 and 12.35 times, respectively, while those of the AACAC specimens increased by 2.40 and 10.94 times, respectively. Finally, the expressions for the ultimate strength and ultimate strain of BFRP-confined CAC and AACAC were proposed, and were compared with tested results of FRP-confined CAC available in the literature to verify the reliability of the proposed models.

Unveiling deep-sea habitats of the Southern Ocean-facing submarine canyons of southwestern Australia

Here we present the outcomes of the first deep-sea remotely operated vehicle study of previously unexplored submarine canyon systems along the southwest Australian continental margin. This was conducted around: (1) the Bremer Marine Park; (2) the Mount Gabi seamount and nearby slope-shelf margin at the interface of the Southern and Indian oceans; with new information from (3) the Perth Canyon Marine Park located in the SE Indian Ocean. These canyons differ from many explored around the world in having no connectivity to continental river systems, thus little detrital input, with the Bremer systems and Mount Gabi facing the Southern Ocean which plays a key role in the global ocean circulation and climate systems. Such studies in the vast deep waters around the Australian continent are rare given the lack of local ROV capability available for research, thus little is known about these environments.Using the resources of the Schmidt Ocean Institute, we characterised the submarine topography from high-resolution bathymetric mapping, geology, physical and chemical oceanography, and provide an overview of these environments including the fauna observed and collected. We show that these Southern Ocean-influenced environments incorporate South Indian Central Water, Subantarctic Mode Water, Antarctic Intermediate Water, and Upper and Lower Circumpolar Deep Water, with Antarctic Bottom Water present in deep water just south of the Bremer canyon systems. The richness in megabenthos, especially along the steep, rocky substrates of the canyon heads and walls around the Bremer canyon systems, contrasts to the comparatively depauperate fauna of the more northerly Perth Canyon. Various corals serve as important substrates for a range of other species and often exhibit particular faunal associations. Especially notable are distinct ecological zones including a bryozoan and sponge-dominated (animal) forest on the shelf edge, spectacular coral gardens along canyon margins, and the occurrence of solitary scleractinians well below the aragonite saturation horizon. Subfossil coral deposits were discovered across all three study areas, reflecting periodic waxing and waning of deep-water Scleractinia throughout this southwest region. Extensive pre-modern assemblages at Mount Gabi contrast markedly with the sparse populations of living species and suggest that it might have once been a major coral hotspot, or whether they reflect long-term coral aggregations is yet to be determined. Nevertheless, stark differences in both living and past coral distribution patterns across our study sites point to at least localised fluctuations in Southern Ocean-derived nutrient and/or oxygen supplies to these deep-sea communities.

Three-Dimensional Mesoscopic Investigation on the Impact of Specimen Geometry and Bearing Strip Size on the Splitting-Tensile Properties of Coral Aggregate Concrete

The use of coral aggregate concrete (CAC) as a novel construction material has attracted significant attention for the construction of reef engineering structures. To investigate the static splitting-tensile behaviors of CAC under the influence of two factors, namely specimen geometry and bearing strip size, a three-dimensional (3D) mesoscale modeling approach with consideration for aggregate randomness in shape and distribution was adopted in this study. We established 12 different specimen models with two specimen shapes (i.e., a cube with an edge length of 150 mm and a cylinder with dimensions of ϕ 150 mm × 300 mm) and six strip widths (i.e., 6, 9, 12, 15, 18, and 20 mm) for calculation. The effects of specimen geometry and strip width on the splitting-tensile properties of CAC, such as failure processes, final failure patterns, and splitting-tensile strength ( f st ), are analyzed and discussed systematically. The results indicate the high reliability of the developed mesoscale modeling approach and reveal the optimal computational parameters for simulating and predicting the splitting-tensile properties of CAC. The f s t values of CAC are associated with both the specimen geometry and width of the bearing strip. The f st values of the cube model are slightly higher than those of the cylinder model for the same bearing strip size, representing geometry effects that can be explained by differences in fracture area. Additionally, the f st value of CAC gradually increases with the relative width of the bearing strip ranging from 0.04 to 0.13. Based on the elastic solution theory, the variation area of CAC f st values with the relative width of the bearing strip was determined preliminarily, which has great significance for studying the tensile performance of CAC.

Bond strength and reliability analysis of stainless steel rebar embedded in fiber reinforced coral aggregate concrete

• The failure pattern of all specimens was that rebars were pull out from concrete. • The content of CFs for optimum bond strength is about 0.6%. • The modified thick-walled cylinder theory can accurately predict the bond strength. • The bond lengths were suggested based on the reliability analysis. In order to take full advantage of local material sources in marine environments, dead coral debris is used as a new type of aggregate to manufactured concrete. Due to that coral aggregate concrete (CAC) presents greater brittleness and the abundant existence of Cl - in CAC, carbon fibers (CFs) and stainless steel rebar (SSR) are adopted to reinforce CAC, so as to improve the mechanics of CAC and the durability of CAC structure. Therefore, it is essential to study the bond performance between CFs reinforced CAC and SSR. In this study, 63 CFs reinforced CAC specimens embedded with SSR were submitted for pull-out tests. All specimens showed a pull-out pattern, and further analysis showed that CAC strength, c / d ( c is the thickness of CAC cover, and d is the SSR diameter), and d / l a ( l a is the bond length) presented an approximately linear relationship with bond strength, while CFs content presented an approximate parabolic relationship with bond strength. Based on the above-mentioned results, a bond strength formula was obtained from regression statistics. Also, suggested bond lengths are given through reliability analysis based on the bond strength formula. Furthermore, corrections concerning the properties of CAC and SSR were made to the thick-walled cylinder model to derive the bond strength theoretically, with results showed that the theoretical value fits well with the experimental value.

Bond behavior of coral aggregate concrete and corroded Cr alloy steel bar

In the extremely hot and humid marine environment in the South China Sea, the application of Cr alloy steel bars and coral aggregate concrete (CAC) overcomes the problems of low durability of ordinary reinforced concrete structures and lack of construction materials, accelerates the construction of reefs. The bond-slip performance between CAC and Cr alloy steel bars is the basis of their cooperative work. Considering the complex composition of the microstructure and the structure of the interface of CAC, and the excellent corrosion resistance of Cr alloy steel bars, the bond properties between Cr alloy steel bars and CAC are different from those of ordinary reinforced concrete. Therefore, in this study, the influence of the corrosion ratio of the Cr alloy steel bar was considered, the corrosion of steel bars was accelerated via electricity, and a pull test was conducted to study the bond-slip constitutive relationship between the corroded Cr alloy steel bar and CAC. Through experimental research and theoretical analysis, the distribution law of the bond stress and slip value between the Cr alloy steel bar and CAC along the anchorage length was obtained under different corrosion ratios. The transfer mechanism of the bond stress and the difference in the bond anchorage position between the Cr alloy steel bar and CAC before and after corrosion were analyzed. A bond anchorage position function model reflecting the actual bond distribution law under different corrosion ratios was proposed and the bond-slip constitutive model was established, providing a reference for island construction in the South China Sea.