Column Model Research Articles

Interaction Analysis between Cationic Lipid and Oligonucleotide with a Lipid Membrane-Immobilized Monolith Silica Column: A High-Performance Liquid Chromatography Approach.

Understanding the interactions between lipid membranes and nucleotide drugs is crucial for nucleic acid therapy. Although several methods have been employed to evaluate nucleotide-lipid membrane interactions, these interactions can be complex; this complexity arises from how external factors, such as ionic strength or temperature, influence the lipid membrane's overall properties. In this study, we prepared a lipid membrane-immobilized monolithic silica (LMiMS) column for high-performance liquid chromatography (HPLC) analysis to understand interactions between the lipid membrane and nucleic acid. First, the Raman shift, zeta potential, fluidity, and polarity of the LMiMS-column membrane were analyzed and compared to dispersed liposomes (not immobilized) with the same lipid composition. The results indicated that the column can effectively imitate the temperature-dependent properties of the lipid membrane, suggesting that the immobilized lipid membrane can be used as a model of dispersed liposomal membranes. Subsequently, HPLC was performed to analyze the interaction between the lipid membrane and oligonucleotides. The retention factor k was determined as an interaction factor between the LMiMS column and nucleic acid models (poly 10, 25, and 50mer dC) at various temperatures and mobile phase salt concentrations. The results revealed that changes in membrane interaction were significant by the phase state and salt concentration. Further analysis of the retention factor k showed that the interaction is weak below the phase transition temperature but strong above the phase transition temperature. The results indicate that membrane properties (rigidity and polarity) are also related to membrane interaction, which can be evaluated with the LMiMS column. This analytical method can provide a new perspective on estimating the interactions between target molecules and the lipid membrane through their temperature-induced dynamics. From these results, our method could be useful for analyzing lipid membrane-oligonucleotide interactions.

Modeling and Optimization of Distillation Column for Separation of 18O Isotope with Mathematical Model

Positron emission tomography (PET) is an advanced imaging tool for the diagnosis and staging of cancer tumors. This method is based on the detection of increased glycolytic activity in malignant cells, in which cell glucose is concentrated because of an increase in membrane glucose transporters, as well as an increase in some key enzymes, such as hexokinase, which are responsible for glucose phosphorylation. Therefore, for this type of imaging, drugs containing glucose are needed. On the other hand, with the expansion of the use of PET imaging devices, the need for drugs for this type of imaging method [fluorodeoxyglucose drug (FDG)] has also increased significantly. FDG is a drug tracer used in the medical imaging technique of PET. The production of FDG requires the production of 18F and, as a result, reaching 18O with a richness of more than 95%. There are various methods to produce oxygen with high richness. Among these methods, using a distillation column is a suitable method to produce oxygen, which has low efficiency and high production cost. Optimization of the distillation column can reduce the cost of producing high-rich oxygen. Numerical methods are one of the useful techniques for optimization. In this study, the distillation column has been computerized using mathematical models, and then by changing the number of inputs, including the height of the pipes, the temperature of the input of the distillation column has been optimized. Results show that the maximum separation of the desired isotope concentration in the distillation tower depends on the type of isotope desired and the condition of the device and is independent of the type of feed. Also, the input feed has no effect on the concentration distribution.

Hybrid Models of Atmospheric Block Columns of Primary Oil Refining Unit Under Conditions of Initial Information Deficiency

Hybrid Models of Atmospheric Block Columns of Primary Oil Refining Unit Under Conditions of Initial Information Deficiency

Flexible Mushroom-Like Cross-Scale Surface with Extreme Pressure Resistance for Telecommunication Lines Anti-Icing/Deicing.

Ice accretion caused by freezing rain or snowstorms is a common phenomenon in cold climates that seriously threatens the safety and reliability of telecommunication lines and other overhead networks. Various anti-icing strategies have been demonstrated through surface engineering to delay ice formation. However, existing anti-icing surfaces still encounter several challenges; for example, surfaces are prone to ice-pinning formation due to the impact of supercooled droplets, which leads to a loss of anti-icing effectiveness. In this study, a mushroom-like cross-scale surface (MCS) with extreme pressure resistance and superior anti-ice-pinning property was reported. Specifically, the designed MCS, featuring multiscale microfeatures, re-entrant structure, heterogeneous sidewalls, and nanoscale particles, exhibits excellent anti-icing properties. Ice formation was determined to occur through a process involving liquid penetration, condensation, icing, and frost filling. By establishing an anti-ice -pinning model and a bubble column model, the relationship between structural characteristics and anti-icing performance was clarified. The MCS demonstrates excellent static liquid repellency (contact angle >167°) and robust dynamic impact resistance (water impact with Weber number ≥300). Furthermore, it exhibits an ultralow ice adhesion strength of 0.46 kPa. Notably, the ice adhesion strength remains below 5 kPa even after 15 deicing cycles. The anti-ice-pinning mechanism and robust icephobicity induced by the micromorphologies of MCS provide valuable insights for effective anti-icing prospects in telecommunication line surfaces and other areas in the field of information and communication technology.

Comparative Adsorption of Porcine Reproductive and Respiratory Syndrome Virus Strains to Minnesota Soils.

Porcine reproductive and respiratory syndrome (PRRS) is an endemic disease affecting the swine industry. The disease is caused by the PRRS virus (PRRSV). Despite extensive biosecurity and control measures, the persistence and seasonality of the virus have raised questions about the virus's environmental dynamics during the fall season when the yearly epidemic onset begins and when crop harvesting and manure incorporation into the field occur. Therefore, this study aimed to assess the potential for PRRSV to percolate through different soil types, simulating conditions that could lead to groundwater contamination which could represent a risk of herd introduction. An experimental soil column model was used to mimic field conditions. Three PRRSV-2 strains were tested across thirteen Minnesota soils with different physical and chemical characteristics. The findings revealed that PRRSV can percolate through all soil types and that the amount of virus percolated decreases with increased amounts of soil. These results suggest that PRRSV can percolate through different soil types. Further investigations should be undertaken to determine the associated implications for swine health and biosecurity measures.

RATING THE LIMITING SHIFT OF A STORY AS A CRITERIA FOR A SPECIAL LIMITING STATE

The article presents a verification of one of the existing seismic resistance criteria found in domestic and international standards. The study examines the limit value of relative displacement of the first-floor column in a reinforced concrete building under seismic loading using two different material models in a nonlinear dynamic framework. The article introduces a modeling approach that allows for the assessment of the seismic resistance of reinforced concrete buildings and structures in a nonlinear dynamic framework. The objective of the work is to verify the standardized limit drift value for a specific structural scheme when modeling the column with volumetric elements including direct reinforcement. Two different material models, implemented in the LS-DYNA software, were used in the column modeling. The first material model is the Karagozian & Case (K&C) Concrete model. This material model represents a three-invariant model with multiple strength and yield surfaces. The model's input parameters include various factors, including empirical ones, such as yield strength, ultimate strength, and residual strength, which are key parameters for the damage accumulation function. The second material model is the Continuous Surface Cap Model, represented by a closed surface (a cap model with a continuous yield surface). This model also accounts for damage accumulation and the degradation of stiffness and strength under cyclic loading. The results include isocontours of the damage accumulation function in concrete, isocontours of strain and stress intensities in concrete and reinforcement at various time steps, as well as graphs of the damage accumulation functions. The findings confirm the accuracy of the numerically determined limit displacement value and identify which material model most precisely represents the failure mechanisms of concrete, thus indicating its suitability for further in-depth research.

A framework for validating efficiency models of thermal separation columns with tray internals

Abstract Tray columns are globally used for distillation processes, and their performance must be optimized to reduce their cost and energy expenditures as well as carbon emissions. A prerequisite to achieve these targets demands a realistic account of the tray performance based on tray efficiency model application. The proof of concept of a Refined Residence Time Distribution (RRTD) model, recently proposed by the authors, is presented. The multifaceted challenges in acquiring hydrodynamic and performance data suitable for model validation are discussed in this work. In that regard, an unprecedented experimental campaign was performed in a representative large-scale air-water tray column simulator based on the application of multiplex flow profiler, new chemical system, and novel data processing schemes. Using these data and additional case studies, the capabilities of the RRTD model were demonstrated. This model successfully accounted for the impacts of varying local liquid flow characteristics and vapor flow maldistributions on the tray efficiency thereby advancing the state of the art of the tray efficiency models. This work particularly aimed at proposing a constructive framework to evaluate tray efficiency models in the future campaigns, and those campaigns will benefit from the learnings of the present work.

Numerical investigation of nonlinear interaction between salinity- and sediment-induced stratification in highly turbid estuaries and coastal seas

ABSTRACT In highly turbid estuaries and coastal seas where freshwater rivers meet the salty ocean, both salinity-induced stratification (SaIS) and sediment-induced stratification (SeIS) are crucial in shaping total estuarine stratification. This study investigates the nonlinearity emerging from the interaction between SaIS and SeIS using a one-dimensional water column model over an erodible bed, driven by a longitudinal salinity gradient and oscillating tidal currents. The results reveal that total stratification deviates significantly from a simple addition of SaIS under clearwater conditions and SeIS under freshwater conditions, indicating a highly nonlinear interaction. The complex spatial and temporal patterns of the nonlinearity arise from the differing source-sink dynamics of salt and sediment. SaIS reduces SeIS during flood but intensifies it during ebb, whereas SeIS consistently strengthens SaIS. This nonlinearity, which exhibits notable flood-ebb asymmetry, is relatively insensitive to changes in tidal forcing compared to salinity gradient forcing, due to the conflicting effects of tidal currents on salinity straining, sediment diffusion, and turbulent mixing. These findings highlight the necessity of incorporating sediment's modulation of classical strain-induced periodic stratification due to salinity gradients in numerical models to improve predictions of buoyancy and stability in highly turbid estuarine and coastal systems.

BIM-based Rebar Modeling for Variable Section L-shaped Columns

Building Information Modeling (BIM), as a kind of digital means applied in the process of building design, construction and management, has been widely used in all aspects of construction engineering. However, the application of BIM in the field of steel reinforcement engineering, due to the wide variety of rebar and complex shapes in the plan construction drawings, the rebar modeling is inefficient and prone to errors, and the traditional plug-in for standard column models is usually difficult to cope with the demand for modeling rebar of complex components such as variable cross-section shaped columns. Therefore, with the help of the program and algorithms to create a BIM model of rebar can reduce the occurrence of the above problems. This paper mainly uses Revit secondary development technology, with the help of C# programming language to develop a program for automatic generation of reinforcing steel BIM model for variable section L-shaped columns. The program combines the structural requirements of reinforcement in the building code and standard drawings, identifies the key nodes of the shaped column model, calculates the coordinate points of the reinforcement, and carries out targeted algorithmic processing for the arrangement of reinforcement in the complex variable cross-section area of the upper and lower columns to complete the creation of the BIM model of reinforcement in the shaped column. The development of this program provides a variety of efficient ideas for the creation of complex structural reinforcement for other shaped columns, which helps to save the time of designers to create BIM models, ensures the geometric accuracy of the reinforcement model, and helps to promote the informatization and intelligentization of the construction of reinforced concrete structures.

Influence of damage degree of recycled coarse aggregate concrete-filled steel tube columns strengthened with envelope steel jacket under seismic load

ABSTRACT In order to discuss the influence of damage degree of recycled coarse aggregate concrete-filled steel tube columns strengthened with envelope steel jacket (ESJ) under seismic load, eight columns were designed and manufactured to simulate seismic loading, with the design of ESJ strengthening after pre-damage and destruct tests under seismic load. This experiment was conducive to accurately evaluating the influence mechanism and synergistic effect of seismic damage degree and recycled coarse aggregate on the hysteresis curve, skeleton curve, ductility performance, energy dissipation performance, and bearing capacity performance of each specimens, and a suitable seismic damage model was proposed. The ductility coefficient is from 3.36 and 4.64, satisfying the requirements of seismic design. The research results indicate that the degree of seismic damage and recycled coarse aggregate are unfavorable to improve the seismic performance of recycled coarse aggregate concrete-filled steel tube columns strengthened with ESJ under seismic load; Taking the ductility coefficient of specimen SEJS-0 as the basic data, specimens SEJS-1 to SEJS-3 and FC-0 to FC-3 increased by 22.02%, 20.24%, 8.33%, 18.15%, 38.10%, 35.71%, and 23.51%, respectively. Under moderate and severe damage, the ductility performance of enveloped steel jacket-strengthened seismic-damaged specimens decreased by 15.47% and 15.18%, respectively, and the reduction amplitude of both was similar. As the degree of seismic damage increases, the value of the ultimate bearing capacity first decreases and then increases. The method of using recycled coarse aggregate to replace half of natural coarse aggregate has certain feasibility in the field of concrete-filled steel tube columns. Recycled coarse aggregate has a significant impact on the bearing capacity of each stage, while the degree of seismic damage only has a greater impact on the ultimate stage. The established seismic damage model for recycled coarse aggregate concrete-filled steel tube columns strengthened with ESJ under seismic load is feasible and can be used for quantitative evaluation of the seismic capacity of such components.

Effect of soil profile-related parameters on seismic performance of ductile reinforced concrete building frames in California

Strong ground motions with specific site characteristics can lead to structural damage. Comprehending the effects of site characteristics on the dynamic response of structures is crucial for evaluating seismic performance and thereby implementing design that can mitigate potential damage. This study explores how the site characteristics, including the average shear wave velocity, soil depth to rock, and site period, influence the seismic response of reinforced concrete buildings. Soil column models were created using 319 soil profiles located in California and were employed to perform the nonlinear site response analysis of 80 rock motions to generate surface motions. Subsequently, low-to high-rise reinforced concrete moment-resisting frames with four, eight, twelve, and twenty stories that are representative of California were modeled to conduct nonlinear structural analyses. In this process, the influence of the three site characteristics on the response of the surface motions and structures was investigated. This investigation revealed that structural responses tend to increase when the average shear wave velocity ranges from 180 to 360 m/s or when the depth exceeds 135 m. Additionally, structures with a natural period exceeding 1 s were found to be more vulnerable as the number of stories increased. The outcomes will promote the development of seismic design methods based on different site characteristics.

Axial and eccentric compressive behavior of partially encased channel–concrete composite columns with bolted connections in modular buildings

This paper introduces a novel partially encased channel–concrete composite (PECC) column for modular buildings, aiming to eliminate the need for cast-in-place concrete and facilitate rapid assembly. The PECC column consists of two prefabricated modules connected by high-strength bolts. To evaluate the column's viability, six slender specimens—one bare steel column and five composite columns—were tested under axial and eccentric compression. Variables considered included the presence of concrete, the type of transverse connections, bolt spacing, and load eccentricity ratio. The compression performance of the PECC columns was analyzed by examining their failure patterns, load–deformation responses, initial stiffness, compressive capacity, and ductility. Test results revealed that the PECC columns failed due to global buckling, concrete spalling, and crushing. The bolted connections effectively prevented module separation, enabling the PECC columns to exhibit favorable compressive behavior. The reinforced concrete encased in the channel delayed the column's buckling failure, increasing its initial stiffness and compressive capacity by 98% and 198%, respectively. Using perforated steel plates instead of transverse links between the concrete and the channel enhanced the column's initial stiffness by 20% but had little effect on its compressive capacity. Reducing the bolt spacing improved the column's initial stiffness and compression resistance by 50% and 5%, respectively. Additionally, a finite element model for the PECC columns was developed and validated against test results. Finally, simplified formulas derived from Eurocode 4 were proposed to estimate the resistance of PECC columns under axial and eccentric compression.

Detectability of biosignatures in warm, water-rich atmospheres

Context. Warm rocky exoplanets within the habitable zone of Sun-like stars are favoured targets for current and future missions. Theory indicates these planets could be wet at formation and remain habitable long enough for life to develop. However, it is unclear to what extent an early ocean on such worlds could influence the response of potential biosignatures. Aims. In this work we test the climate-chemistry response, maintenance, and detectability of biosignatures in warm, water-rich atmospheres with Earth biomass fluxes within the framework of the planned LIFE mission. Methods. We used the coupled climate-chemistry column model 1D-TERRA to simulate the composition of planetary atmospheres at different distances from the Sun, assuming Earth’s planetary parameters and evolution. We increased the incoming instellation by up to 50% in steps of 10%, corresponding to orbits of 1.00 to 0.82 AU. Simulations were performed with and without modern Earth’s biomass fluxes at the surface. Theoretical emission spectra of all simulations were produced using the GARLIC radiative transfer model. LIFEsim was then used to add noise to and simulate observations of these spectra to assess how biotic and abiotic atmospheres of Earth-like planets can be distinguished. Results. Increasing instellation leads to surface water vapour pressures rising from 0.01 bar (1.31%, S = 1.0) to 0.61 bar (34.72%, S = 1.5). In the biotic scenarios, the ozone layer survives because hydrogen oxide reactions with nitrogen oxides prevent the net ozone chemical sink from increasing. Methane is strongly reduced for instellations that are 20% higher than that of the Earth due to the increased hydrogen oxide abundances and UV fluxes. Synthetic observations with LIFEsim, assuming a 2.0 m aperture and resolving power of a R = 50, show that ozone signatures at 9.6 µm reliably point to Earth-like biosphere surface fluxes of O2 only for systems within 10 parsecs. The differences in atmospheric temperature structures due to differing H2O profiles also enable observations at 15.0 µm to reliably identify planets with a CH4 surface flux equal to that of Earth’s biosphere. Increasing the aperture to 3.5 m and increasing instrument throughput to 15% increases this range to 22.5 pc.

Combined clogging of suspended particle and algae during the recharge with the Yellow River water in the Yufuhe River channel of North China Plain

ABSTRACT Managed aquifer recharge (MAR) is an effective measure for integrated water resources in the North China Plain (NCP). During the recharging, the combined clogging in the aquifer caused by algae and suspended solid (SS) is a problem that was easily ignored by researchers. In this research, a sand column model was designed to investigate the SS-algae combined clogging mechanism in the porous medium during the Yellow River water recharge in the Yufuhe River channel of NCP. The SS-algae combined plugging of the medium appeared earlier and the plugging degree was more serious compared with the SS-only clogging and the algae-only clogging during the infiltration. Meanwhile, the surface clogging degree of the medium is more serious, and the interior is smaller in comparison to the SS-only group and the algae-only group. The filter cake and algae mat are the signs of SS clogging and algae clogging, and the algae mat structure in the SS-algae group is more dense compared to the algae-only group. In the combined clogging experiment, the outflow concentration of SS and algae in the medium is less than the SS-only group and the algae-only group. In addition, algae and SS can limit each other's migration in the medium.

Mechanical performance and strength prediction model of demountable RC columns with a novel bolts-flange connection

This paper developed a novel bolted flange connection and applied it to prefabricated reinforced concrete columns, forming a demountable reinforced concrete column (DRCC). The proposed column-column connection is designed of two main parts: 1) the connection of the rebar to the flange plate; and 2) the connection of the flange plate to plate. The connection could simultaneously satisfy load transfer as well as demountability. The detailed features and construction method of DRCC were introduced firstly. Then, DRCC specimens and cast-in-place specimens were designed and static tests were performed with different eccentricities. The results showed that DRCC specimens present similar damage patterns as cast-in-place specimens, which could be classified to large and small eccentric compression damage. The loading capacity and stiffness of DRCCs is slightly less than that of cast-in-place specimens for the same eccentricity. In the case of large eccentricity damage, the ductility of DRCC is superior to that of cast-in-place specimen. Furthermore, finite element (FE) models of DRCC were developed and validated. The loading capacity, initial stiffness, flange stress and concrete damage under various eccentric ratio are compared by FE parametric analysis. Finally, the modified formula for loading capacity of DRCCs is proposed, and the modified factors c1 and c2 are determined to be 0.85 and 0.90 using tests and FE analysis data. The N-M interaction curve of DRCC is presented based on the modified formula. Compared with the results from tests and FE analysis, the predicted values of N-M curves are tending towards safety.

Numerical analysis, resistance, and behaviour of concrete-filled double-skin corrugated steel tubular short columns

Currently, research and engineering communities have a substantial increase in interest in the design and behaviour of novel arrangements for double-skin composite columns. This includes the concrete-filled double-skin corrugated steel tubular (CFDSCST) columns. Accordingly, this paper investigates the resistance and behaviour of CFDSCST short columns under axial compression. Finite element (FE) models for CFDSCST short columns were generated and validated using available experimental tests. Then, a parametric study was generated to suggest a new lateral confining pressure for the sandwiched concrete. This is followed by exploring these columns' axial resistance and behaviour, considering different influencing factors, such as the depth-to-thickness ratio, concrete cylindrical compressive strength, hollow ratio and steel strength. Two main column configurations were considered: outer corrugated steel tubes (OCs) and inner corrugated steel tubes (ICs). The FE-predicted resistances were then compared with the codified resistances of the British, European, and Chinese. Generally, these methods produced conservative predictions for both OC and IC columns. Hence, based on the so-called confinement-based design, a new resistance was provided for the CFDSCST short columns based on the proposed power-law formulae for the lateral confining pressure caused by the tubes with corrugations. It was found that IC columns provide more confinement and a lower ductility index compared to OC columns. Concerning the behaviour, it was found that increasing tube thickness and concrete strength leads to increased column resistance, while increasing the concrete strength produces a column of reduced ductility. Additionally, increasing the hollow ratio, which reduces the sandwich concrete cross-sectional area, leads to a decreased column resistance, while increasing the steel strength, while maintaining the sandwich concrete cross-sectional area, increases the column resistance.

Removal of Sulfadimethoxine in Aqueous Solution by Adsorption on Mesoporous Carbon/Titania Composites: Batch Scale, Fixed-Bed Column, and Bayesian Modeling

Removal of Sulfadimethoxine in Aqueous Solution by Adsorption on Mesoporous Carbon/Titania Composites: Batch Scale, Fixed-Bed Column, and Bayesian Modeling

Probabilistic modelling of steel column response to far-field detonations

Due to the deficiency of current design guidelines for blast loadings on steel structures, this research develops probabilistic models for steel wide-flange columns under axial and far-field blast loading on both their weak and strong axes. A total of 160 finite element (FE) simulations were conducted using ANSYS LS-DYNA, with columns subjected to different Axial Load Ratios (ALRs) and blast impulses. Validation against two experimental tests showed a strong correlation in displacement plots, with a material model accounting for strain rate effects. Probabilistic models for predicting maximum displacement and residual axial capacity were formulated using Bayesian inference and posterior statistics. These models were developed by incorporating dimensionless physics-based explanatory functions. The slenderness ratio of the column was identified as the most influential. The models account for uncertainties such as material and geometric properties, as well as strain rate effects. Graphical plots between the ALR and Damage Index (DI) were examined to assess the column's damage level. Furthermore, the probability of failure (fragility) of four columns for similar blast impulse was assessed w.r.t DI. These models along with ALR vs DI plots will be useful tools to know the level of building occupancy and retrofitting options.

An Assessment of the Bearing Capacity of High-Strength-Concrete-Filled Steel Tubular Columns Through Finite Element Analysis

This work aimed to evaluate the accuracy of analytical models for predicting the behavior of concrete-filled steel tubular (CFST) columns via finite element analysis coupled with physical nonlinearity. The methodology involved an extensive review of experimental tests from the literature, numerical modeling of columns with different configurations, and a comparison of the results obtained with available experimental data. Several characteristics were evaluated, such as the load capacity, confinement factor, and relative slenderness. The numerical model agreed well with the experimental results, with a less than 10% relative error. The results indicated that analytical models of the Chinese (GB 50936) and European (EC4) codes overestimated some load capacity values (up to 14.9% and 8.7%, respectively). In comparison, the American (AISC 360) and Brazilian (NBR 8800) standards underestimated the ultimate loads (23.3% and 31.6%, respectively). An approach coefficient β is proposed, contributing to safer and more efficient design practices in structural engineering.

Numerical analysis of axially loaded concrete-filled steel tubular columns strengthened with CFRP grid-reinforced ECC

Carbon fiber-reinforced polymer (CFRP) and engineered cementitious composites (ECC) are commonly used to reinforce structural elements, with proven effectiveness in enhancing the performance of concrete-filled steel tube (CFST) columns as shown in prior experimental studies. However, the complex interaction among the components of the reinforced columns, including CFRP, ECC, the steel tube, and the concrete core, as well as the underlying mechanical mechanisms, remain insufficiently understood. This research aims to fill these gaps by developing a 3D finite element (FE) model of circular CFST short columns reinforced with CFRP grid-reinforced ECC for comprehensive numerical analysis. Sensitivity analyses are conducted to determine the governing parameters in the numerical simulation, including mesh size and critical plasticity parameters for the concrete damage model, such as the ratio of the second stress invariant on the tensile meridian to that on the compressive meridian (Kc), and the dilation angle (ψ) for both the concrete core and ECC. The model also accounts for the effects of concrete confinement provided by the CFRP grid-reinforced ECC layer and the circular steel tube. The accuracy of the FE model is validated against existing experimental data, and the model is subsequently used to investigate the behavior of reinforced CFST columns under varying geometric and material properties. The study examines failure modes, axial load-displacement responses, stress distributions, and the contribution of each material component to the load-bearing capacity of the strengthened columns. The results indicate an increase in ultimate axial strength ranging from 13% to 20% for the reinforced CFST columns. While the compressive strength of the ECC has a moderate effect on axial resistance, increasing ECC thickness, concrete strength, and steel tube yield strength significantly enhances the columns’ load-bearing capacity. Finally, a novel design model is proposed and validated, which accounts for the confinement effects provided by the CFRP grid and ECC on the concrete core.