Fiber Reinforced Polymer Sheets Research Articles

Behavior of Reinforced Concrete Beams without Stirrups and Strengthened with Basalt Fiber–Reinforced Polymer Sheets

This paper reports on a series of four-point bending experiments to investigate the shear capacity of reinforced concrete (RC) beams strengthened with externally bonded basalt fiber–reinforced polymer (BFRP) sheets. The experimental results show that BFRP sheets can significantly increase RC beams’ shear capacity and ductility. To analyze the fracture and mechanical behaviors of BFRP sheet–strengthened RC beams, a three-dimensional (3D) finite-element model (FEM) based on the application of cohesive elements was developed. Mixed-mode constitutive models of the BFRP–concrete interface, the concrete potential fracture surface, and the reinforcement–concrete interface were proposed. The proposed constitutive models were able to characterize the interface’s normal separation, tangential slip, and friction. A comparison of the simulation and experimental results indicates that the proposed numerical model can appropriately simulate the mechanical response, crack propagation, and crack distribution of BFRP sheet–strengthened RC beams. Finally, based on the proposed 3D FEM, a series of numerical tests were conducted to investigate the influence of key parameters (i.e., sheet elastic modulus, sheet bonding area, and sheet bonding angle) on the shear capacity of BFRP sheet–strengthened RC beams.

Flexural capacity enhancing of notched steel beams by combining shape memory alloy wires and carbon fiber-reinforced polymer sheets

Combining shape memory alloy (SMA) and carbon fiber-reinforced polymer (CFRP) sheet can achieve a self-stressing SMA-CFRP composite, providing an innovative prestressing method for steel elements. This study applied SMA(Ni–Ti–Nb) wires and CFRP sheets to achieve composite strengthening for notched steel beams. The effectiveness of SMA-CFRP composite for flexural strengthening of notched steel beams was evaluated, and the formula for the maximum allowable moment of the strengthened beams with SMA-CFRP composites was proposed. The four-point bending test results showed that the ultimate load and flexural stiffness of the strengthened beams with SMA-CFRP composites increased by 79.2% and 57.9% more than those of the unstrengthened beams. By comparison, the CFRP-only and SMA-only strengthened beams merely achieved half the ultimate load and flexural stiffness over the strengthened beams with SMA-CFRP composite. Besides, compared to the unstrengthened beams, the notch tip yield load for the strengthened beam with SMA-CFRP composite was increased by 230%, while the notch tip yield load for strengthened beams with CFRP-only and SMA-only just increased by 70% and 125%. These indicate that the SMA-CFRP composite strengthening can significantly delay crack propagation and improve the load capacity and stiffness of notched steel beams. Moreover, the analytical results of the maximum allowable moment were in good agreement with experimental results, indicating the accuracy of the proposed analytical equations.

Improving cyclic response of heat-damaged non-ductile RC joints using CFRP hybrid systems

The behavior of non-ductile, heat-damaged reinforced concrete (RC) beam column joints was investigated in this experimental research work. A hybrid system formed of carbon fiber-reinforced polymer (CFRP) sheets and strings was used to improve the cyclic response of these non-ductile, heat-damaged joints. To evaluate the cyclic performance of these joints, twelve RC beam-column joints were cast and classified into four categories: Three joints were kept without strengthening as control specimens. Three joints were strengthened with one layer of CFRP sheets and one NSM-CFRP string in the beam and in the column; three joints were strengthened with two layers of CFRP sheets and two NSM-CFRP strings in the beam and in the column; and three joints were strengthened with three layers of CFRP sheets and three NSM-CFRP strings in the beam and in the column. In addition, the joints were tested at three different temperatures, which are: ambient, 400 °C, and 600 °C. The experimental findings show a considerable improvement in the cyclic performance of non-ductile heat-damaged RC beam-column joints strengthened with a hybrid CFRP system (greater lateral displacement, higher load capacity, higher energy dissipation, higher displacement ductility, and slower secant stiffness degradation). Furthermore, the effectiveness of CFRP composites increases as the degree of heat damage increases.

Efficiency of CFRP torsional strengthening technique for L-shaped spandrel reinforced concrete beams

Abstract The present study aims to get experimentally a deeper understanding of the efficiency of carbon fiber-reinforced polymer (CFRP) sheets applied to improve the torsional behavior of L-shaped reinforced concrete spandrel beams in which their ledges were loaded in two stages under monotonic loading. An experimental program was conducted on spandrel beams considering different key parameters including the cross-sectional aspect ratio (i.e., web height/web thickness), and the availability of the CFRP strengthening system. The ledge of the spandrel beams was exposed during testing to a very high eccentric load, which was transferred to the web of the spandrel beam causing high shear, torsion, and bending moments. Consequently, the applied load resulted in in-plane and out-of-plane deformations of the web accompanied by flexural and shear cracks. This article demonstrates the advantage of using CFRP sheets to strengthen the mentioned members. The applied CFRP sheets increased the failure torsional load by about 37% compared to the identical L-spandrels without strengthening. The outcomes indicate that using CFRP sheets show improvement in restricting the deflections and rotation of L-spandrels due to increasing spandrel stiffness. The reduction in the degree of rotation attained more than 33% in comparison to the spandrel beams without strengthening. The experimental program confirmed the applicability of the proposed strengthening technique for compacted and slender L-shaped spandrel-reinforced concrete beams.

Behavior of GFRP reinforced concrete slabs with openings strengthened by CFRP strips

The utilization of fiber-reinforced polymer (FRP), can be an efficient, and long-lasting solution for increasing the durability of reinforced concrete (RC) structures in hostile environments. FRP can be used as a reinforcement or as a strengthening technique that may recover the load capacity of a structure. This paper aims to investigate the flexural behavior of one-way concrete slabs with openings reinforced by glass fiber-reinforced polymers (GFRP) bars and strengthening using carbon fiber-reinforced polymer (CFRP) sheets. The experimental work consists of five one-way concrete slabs that were tested up to failure. All slabs had the same dimension, 750*2650 mm, with a thickness of 150 mm, and were reinforced with the same reinforcement ratio. The experimental work included one specimen without openings and without strengthening as a solid slab. While, the remaining slabs were fabricated with two different openings, rectangular and square 250*500 mm, and 250*250 mm respectively, and strengthened by CFRP sheets. The test results show that the failure load of existing slabs with mid-span openings is decreased by around 41% and 43%, for one and two openings respectively, compared to the solid slab. The utilization of CFRP sheets enhances the flexural load-carrying capacities by about 52% and 44% and improves the stiffness at the ultimate load by about 101%, and 95%, and decreases the deflection at a service load by about 56% and 54%, respectively compared with the un-strengthened slabs. Furthermore, the experimental data were used to validate a finite element (FE) model along with an additional parametric study.

Numerical analysis of reinforced concrete beams subjected to impact loads

Abstract Numerical models for impact load assessment are becoming increasingly reliable and accurate in recent years. The processing time duration for such analysis has been decreased to an acceptable level when combined with modern computer hardware. The aim of this study was to represent a simulation technique and to verify the validity of modern software in measuring the response of reinforced concrete beam strengthened by carbon fiber-reinforced polymer (CFRP) sheet subjected to impact loads at the ultimate load ranges. In this investigation, ABAQUS/Explicit Software’s nonlinear finite element modeling had been used. The response of the impact force–time history and the displacement–time history graphs were compared to the existing experimental results. The adopted general-purpose finite element analysis is verified to be capable of simulating and accurately forecasting the impact behavior for structural systems. In addition, a parametric analysis was carried out to gain a better knowledge of the performance of reinforced concrete beams under impact loading. Four parameters had been changed among the analyzed beams such as impact velocity, impact mass, CFRP sheet thickness, and compressive strength of concrete. Generally, it has been found that using a CFRP sheet in strengthening reinforced concrete beams can greatly improve the members’ impact behavior by improving stiffness as well as increasing load-carrying capacities. The enhanced performance characteristics of strengthening beams under impact loads correlate with the applied kinetic energy and CFRP thicknesses. Finally, for beams with high compressive strength, the deflection values were reduced because of the increase in stiffness.

Ultimate torsional resistance and failure modes of FRP-strengthened reinforced concrete members: A nonlinear design model

Reinforced concrete (RC) structural members, especially flanged and spandrel beams, bridge girders, curved beams, and eccentrically loaded beams may be subjected to significant torsional loading. Despite extensive research on the strengthening of RC members, far too little attention has been paid to the torsional behavior of RC members strengthened with fiber-reinforced polymer (FRP) sheets. Therefore, a limited number of guidelines specified the design of externally bonded FRP systems in torsion. This study provides an important opportunity to advance the understanding of the torsional behavior of FRP-strengthened members by developing a nonlinear design model predicting the failure mode and ultimate torsional resistance of FRP-strengthened RC members subjected to torsion. Serious discussions and analyses of desired failure modes emerge by defining two balanced conditions between the components, and eight failure regions. The first balanced condition defined between FRP and concrete specifies the failure mode of the member, and the second balanced condition defined between steel and concrete is used for the analysis of steel reinforcement stresses. A clear design approach is proposed in this study to access the desired percentage of the externally applied FRP sheets based on the required torsional strength. Moreover, the ultimate stresses and strains of concrete struts, steel reinforcements, and FRP sheets are derived by incorporating the nonlinear behavior of concrete. To evaluate the validity of the design method, 70 FRP-strengthened specimens are collected from 11 previous studies; then, a comparative analysis is conducted among the experimental results, the estimations of the presented model, and the predictions of the commonly available guidelines for torsional strengthening. The excellent agreement between the test results and the presented model estimations confirms the validity and accuracy of the presented model.

A State-of-the-Art Review on Axial Compressive Behavior of Concrete-Filled Steel Tubes Incorporating Steel Fiber and GFRP Jacketing

Several types of fibers have enhanced the structural response of reinforced concrete-filled steel tubes (CFSTs). This article presents a state-of-the-art review of studies done on the axial compressive behavior of steel and glass fiber-reinforced CFSTs. The aim of using fibers is to improve the response of the CFSTs. This research indicates the findings of experimental programs and analytical evaluations of the effects of the fiber incorporation on the behavior of the CFSTs. The results of this research work demonstrate that steel fibers (SFs) have enough evident improving effects on the failure mode and load-carrying capacity of the CFSTs. The SFs greatly increase the ductility of the CFSTs. To enhance the compressive strength and ductility of the CFSTs, adding the SFs by 1% to the concrete mix is more effective than adding by 1.5%. The use of the SFs mixed with expansion agent considerably increases the yield and ultimate loads of the CFSTs. More glass fiber-reinforced polymer (GFRP) sheets reduce buckling and develop the compressive strength of the CFSTs. The implementation of the GFRP jackets not only enhances the load-carrying capacity of the CFSTs, but also increases their ductility. The GFRP reinforcement techniques for the CFSTs are also effective in improving their structural stiffness and energy absorption capacity.

Rehabilitation of Shear damaged Reinforced Concrete Beams with U-Wrapped Carbon Fiber Reinforced Polymer Sheets: Experimental study

This paper presented an experimental study of external rehabilitation of damaged Reinforced Concrete (RC) Beams with Carbon Fibre Reinforced Polymer (CFRP) sheets. The primary objective is to study the shear behavior of four simply supported beam specimens with an total length of 1700mm, a width of 150 mm, and a depth of 250 mm was tested under a monotonic two-point load. The variable used in this study was the specimen damage ratio (50%, 60%, and 70%), while the layout of CFRP sheets and shear-span to effective depth ratio (a/d = 2.5) were kept constant. The design of the examined beams was according to ACI 318M-19 to ensure shear failure. From this study, it was concluded that external rehabilitation with U-shape CFRP sheets offered a very adequate and efficient rehabilitation method for damaged RC beams. Each beam's behavior was examined concerning the crack pattern, first crack load, load-deflection and ultimate load. The CFRP rehabilitation has improved the ultimate load capacity of damaged beams by about 10.91% to 15.96% compared with the expected remaining ultimate load capacity of control specimens without rehabilitation, as well as an increment in the deflection of mid-span from -6.81%, 24.11% at an ultimate load.

Stepped Reinforced Concrete Beams Retrofitted with Carbon Fiber-Reinforced Polymer Sheets and Ultra-High- Performance Concrete

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Effect of corroded reinforcement on capacity of square reinforced concrete columns confined with FRP sheets under eccentric loads

Steel corrosion is one of the primary causes which significantly degrade the load-carrying capacity and FRP (fibre reinforced polymer) strengthening efficiency of FRP-strengthened reinforced concrete columns under eccentric loading. However, this issue has not been studied comprehensively and systematically in the literature. Particularly, there has been no study on the strengthening efficiency of basalt FRP (BFRP) which is becoming popular due to its excellent performance and affordable price. This study experimentally investigates the effect of corrosion level of reinforcement by mass (0%, 15% and 30%), relative eccentricity (e/h = 0.125 and 0.375), type of FRP (CFRP and BFRP) and FRP thickness (1 or 3 layers) on the load-carrying capacity and deformation of corroded-reinforcement reinforced concrete (RC) columns. The experimental results showed that steel corrosion reduced the load-carrying capacity of the unstrengthened RC columns up to 23% and this degradation increased with the corrosion level. Both CFRP and BFRP have proven excellent strengthening efficiency since the capacity of the FRP-strengthened corroded-reinforcement RC columns increased up to 47%. Particularly, the strengthening efficiency of BFRP sheets was slightly lower than that of CFRP sheets (<7%). On the other hand, the increase of the relative eccentricity from e/h = 0.125 to e/h = 0.375 reduced the strengthening efficiency of FRP. In addition, a semi-empirical model was proposed to predict the capacity of corroded-reinforcement RC columns strengthened with FRP under eccentric loading. The predictions match well with the experimental results with a small coefficient of variation.

Properties of Concrete Columns Strengthened by CFRP-UHPC under Axial Compression

Ultra-high-performance concrete (UHPC) is a kind of structural material with ultra-high strength, extremely low porosity, and excellent durability, which has extremely broad application prospects. In order to promote the application of UHPC constrained by carbon fiber-reinforced polymer (CFRP) sheets as strengthening material in practical engineering, a total of nine specimens were designed, and two kinds of UHPC strengthening layer thickness (35 mm and 45 mm, respectively) were designed. By changing the constraint form of the UHPC strengthening layer (longitudinal reinforcements and ordinary stirrups, longitudinal reinforcements and spiral stirrups, and CFRP sheets, respectively), the axial compression performance of the strengthened column was explored. The study shows that compared with the without strengthened column, the uplift of carrying capacity of the strengthened test column is 277–561%. The reinforcement form of the strengthening layer has little influence on the lifting capacity. Among the three different strengthening methods, the wrapped CFRP has the best improvement effect on carrying capacity and ductility, followed by longitudinal reinforcements and spiral stirrups in the strengthening layer. With the increase of CFRP layers from two to five layers, the maximum carrying capacity increases by 21.3%. The carrying capacity of three different types of UHPC-strengthened columns is theoretically calculated, and the accuracy of the theoretical calculation method is verified by comparing the test value with the theoretical value, which provides a theoretical basis for the application of UHPC-strengthened columns in the future.

Experimental tests of FRP-HSC hybrid beams under four-point bending

This paper provides an experimental study of a new fiber-reinforced polymer (FRP)-high strength concrete (HSC) hybrid beam, which consists of a glass FRP (GFRP) I-shaped profile beam strengthened with a layer of HSC on top and carbon FRP (CFRP) sheets on the web. In this study, a total of two GFRP I-shaped profile beams, two GFRP I-shaped profile beams strengthened with CFRP sheets on the web and nine FRP-HSC hybrid beams were tested under four-point bending loading. The test parameters varied for the existence of CFRP sheets, the flange width of the GFRP profile, the width of the HSC slab, the type of shear connectors and the interfacial connection method. The test results indicated that bonding CFRP sheets, increasing the flange width and HSC slab width all showed positive effect on the ultimate bearing capacity and initial rigidity. Compared with U-shaped GFRP shear keys and inverted T-shaped GFRP shear keys, the hybrid beams using steel bolts had the highest ultimate load capacity and initial rigidity. The hybrid beams using the composite-bond interface (CB) performed better than the hybrid beams using wet-bond (WB) and dry-bond (DB) interfaces.

Experimental study on the effects of external strengthening and elevated temperature on the shear behavior of ultra-high-performance fiber-reinforced concrete deep beams

The shear behavior of deep beams, especially of ultra-high-performance fiber-reinforced concrete (UHPFC), is rather intricate, as it depends on several factors, including its depth, concrete strength, amount of flexural and shear reinforcements, the ratio of shear span to depth, and the bearing area under the load and at the support. Moreover, these beams may be exposed to elevated temperatures requiring strengthening, which has not been adequately studied. This study examines experimentally the shear capacity of UHPFC deep beams strengthened using carbon fiber-reinforced polymer (CFRP) sheets for improving the shear strength of deep beams after exposure to an elevated temperature. Eight specimens were cast in four groups of two specimens each. Testing of the beams of the first group was performed at the ambient temperature, whereas the beams of the second group were tested after being exposed to a temperature of 450 °C. For the third group, the deep beams were strengthened by CFRP U-wrap strips and tested at the ambient temperature, whereas the beams of the fourth group were subjected to the elevated temperature of 450 °C, followed by strengthening using CFRP U-wraps and then testing to collapse. The test results indicated that the post-peak behavior was affected significantly by the elevated temperature. Moreover, the experimental results indicated the excellent performance of strengthening schemes in improving the post-cracking behavior of UHPFC deep beams, enhancing shear strength (up to 16 %), energy-based ductility index (39 % to 648 %), and deflection ductility index (68 % to 144 %). An analytical model is developed to predict the load-carrying capacity of UHPFC deep beams strengthened after exposure to elevated temperature.

Modeling and prediction of short/long term mechanical behavior of FRP-strengthened slabs using innovative composite finite elements

The analysis of plates or slabs strengthened with fiber reinforced polymer (FRP), especially when it comes to geometric irregularity and the time-varying characteristics of adhesive, presents multi-faceted simulation, modeling and computational challenges. In this paper, two new multilayer composite plate elements are proposed to model and analyze FRP-strengthened slabs, aiming at meeting these challenges with efficiency. The novelty relies on that the innovative elements realize the modeling of substrate, adhesive layer and FRP sheet in one “macroscopic” element rather than modeling each component by separate elements. One of them is capable of emulating geometric irregular structures while the other has better accuracy, and the flexible combination of them can be used to achieve accurate simulation and calculation of various strengthening systems. Another novelty is the extension of the study from elastic to viscoelastic by introducing an appropriate rheological interface and correspondence principle. The consistency with literature verifies the correctness of the proposed elements, subsequently, they were used to investigate the influence of the FRP tapering ends and strengthening forms on the reinforcement effectiveness. It is found that the proposed method is convenient to predict the short/long term mechanical behavior of FRP strengthened slabs with accuracy and computational efficiency, thus contributing to the design and optimization of the strengthening system.

Evaluation of flexural strengthening methods for beams with simulated deterioration using spike-anchored FRP externally bonded sheets and near-surface-mounted strips

• 20 beams were tested to evaluate FRP flexural strengthening techniques. • Specimens were detailed to mimic the common deterioration of bridge beams. • The effect of FRP spike anchor arrangements were evaluated. • Results show that more FRP spike anchors may not translate to superior performance. • Unsymmetrical steel and NSM reinforcement layouts were considered. In consideration of past research on both externally bonded and near-surface-mounted (NSM) fiber-reinforced polymer (FRP) reinforcement for the strengthening of deteriorated reinforced concrete elements, additional work is needed to investigate the application of FRP for flexural strengthening in specific scenarios and for specific member types. Furthermore, the need exists for guidance regarding reliable anchorage of externally bonded sheets for flexural strengthening. An experimental investigation was conducted on 20 reinforced concrete beam specimens with details and simulated deterioration patterns representative of the beams of in-service adjacent box beam bridges. Special focus was placed on the effective arrangement of FRP spike anchors for externally bonded FRP, unsymmetrical deterioration of steel reinforcement, and the eccentric placement of NSM strips. The results show that spike anchors located only at the ends of the externally bonded FRP sheets provided superior performance compared to anchors placed at multiple locations along the sheets. Moreover, the eccentricity of reinforcement did not play a significant role in the effectiveness of the strengthening systems. The test results also highlight the importance of bond on the performance of members strengthened with NSM reinforcement. Overall, the findings extend beyond adjacent box beam bridges and have a wide applicability to other flexural members.

Design method for glulam beams strengthened with flax fiber reinforced polymer sheets

The strengthening efficiency of flax fiber reinforced polymer (FFRP) reinforcement is evaluated by four-point bending tests, conducted on full-scale glulam beams strengthened with FFRP sheets. Experimental variables include different layers (three-layer or six-layer), attaching types (unidirectional or bidirectional), and attaching configurations (longitudinal, U-shaped or fully wrapped). The failure modes, load-deflection curves, strain changes, load capacities, flexural rigidity, energy absorption, and ductility of the tested specimens were recorded and discussed. Results indicate that the bending performance of a beam strengthened with three-layer longitudinal FFRP sheets outperforms that of a six-layers. The strengthening efficiency of bidirectionally attached FFRP is significantly higher than that of unidirectionally attached FFRP. Furthermore, a theoretical model for the ultimate load of test beams was developed and validated on the basis of these results, demonstrating good agreement with the experimental results. The design value of tensile strength for FFRP sheets was determined by reliability analysis. Based on the test data and recommended values for tensile strength of FFRP sheets, the reliability indexes β for the design formulas were calculated to further verify their applicability and reliability. Finally, the global modification factors for design formulas were calculated and recorded to achieve the target reliability requirement (β = 3.2 specified in the Chinese code GB50005-2017).

Enhancement of the Fragility Capacity of RC Frames Using FRPs with Different Configurations at Joints.

This paper reports the results of an investigation into the effectiveness of different lengths of Fiber-Reinforced Polymer (FRP) sheets in retrofitting the joints of Reinforced Concrete (RC) frames to improve the fragility function of ordinary RC frames. Several 8-storey RC buildings were investigated through FE modelling. The accuracy of the FE models was verified using peer research results. Fragility curves of FRP-retrofitting joints of two referenced RC frames were carried out by OpenSees, through Incremental Dynamic Analysis (IDA) analysis under 22 far-field earthquake records from 0.1 g to 4.0 g (with 0.1 g interments), based on FEMA P-695. Two types of retrofitting methods, web and flange bonding, were modeled and studied. The results showed that the fragility capacity of the retrofitted RC frames was significantly improved. Moreover, frames with longer sheets of FRP showed increased performance. In the complete state, the range of probability of exceedance grew from 2-2.5 g to 3-3.5 g (nearly 1 g), whereas, in the minor state, this growth was nearly 0.05 g. However, the fragility function of the flange-bonding was enhanced at a higher rate compared with that of the web-bonding RC frames. Carbon Fiber-Reinforced Polymer (CFRP) and Glass Fiber-Reinforced Polymer (GFRP) materials improved the probability of exceedance of the complete state from 3 g to 4.5 g and 4.8 g in flange bonding frames. This enhancement for both types of frames was more significant when joints were retrofitted with 400 and 500 mm compared with 600, 700, and 800 mm. The midpoint of the PGA at the complete damage state in the web-bonding frame increased from 1.076 g to 1.664 g and in the flange-bonding frame retrofitted with GFRP and CFRP raised from 1.551 g to 2.769 and 3.076, respectively. The collapse margin ratio (CMR) indicates an acceptable improvement in the retrofitted frames. Overall, the rate of enhancement in fragility function from the original frame to the frame with 500 mm FRP was significant; however, the slope of this rate declined for longer FRP sheets. The fragility performance improvement resulted in controlling plastic hinging by FRPs.

Computer Simulations of End-Tapering Anchorages of EBR FRP-Strengthened Prestressed Concrete Slabs at Service Conditions.

This article examines numerically the behavior of prestressed reinforced concrete slabs strengthened with externally bonded reinforcement (EBR) consisting of fiber-reinforced polymer (FRP) sheets. The non-linear finite element (FE) program Abaqus® is used to model EBR FRP-strengthened prestressed concrete slabs tested previously in four-point bending. After the calibration of the computational models, a parametric study is then conducted to assess the influence of the FRP axial stiffness (thickness and modulus of elasticity) on the interfacial normal and shear stresses. The numerical analysis results show that increasing the thickness or the elastic modulus of the FRP strengthening affects the efficiency of the FRP bonding and makes it susceptible to earlier debonding failures. A tapering technique is proposed in wet lay-up applications since multiple FRP layers are often required. It is shown that by gradually decreasing the thickness of the FRP strengthening, the concentration of stress along the plate end can be reduced, and thus, the overall strengthening performance is maximized. The tapering is successful in reducing the bond stress concentrations by up to 15%, which can be sufficient to prevent concrete rip-off and peel-off debonding failure modes. This article contributes towards a better understanding of the debonding phenomena in FRP-strengthened elements in flexure and towards the development of more efficient computational tools to analyze such structures.

Experimental and Numerical Investigation of an Innovative 3DPC Thin-Shell Structure

The development and application of new Fiber Reinforced Polymer (FRP) material and 3D printing construction technology provide a basis for making up for the shortcomings of traditional thin-shell structures and building new thin-shell structures with better performance. In this paper, a new 3D Printing Composite (3DPC) thin-shell structure is proposed, which is prepared using a FRP plate as a permanent base mold and combining it with 3D printing cement technology. Both the typical experiment and finite element numerical simulation analysis of the 3DPC thin-shell structure are carried out. The results show that the maximum load capacity of the 3DPC thin-shell structure is increased by 53.3% as compared with the corresponding traditional concrete thin-shell structure. The presence of the FRP sheet effectively delays the generation of initial cracks and enhances the ductility of components.