Experimental Test Setup Research Articles

Development and Assessment of a Miniaturized Test Rig for Evaluating Noise Reduction in Serrated Blades Under Turbulent Flow Conditions

The implementation of serrated stator blades in axial compressor and fan stages offers significant advantages, such as enhanced performance and reduced noise levels, making it a practical and cost-effective solution. This study explores the impact of serrated blade design on noise reduction under specific engine operating conditions. A small-scale experimental test setup with a turbulence-inducing grid was designed for testing multiple grid sizes in order to identify the most promising configuration which replicates rotor–stator interaction. Numerical simulations and early experimental tests in an anechoic chamber using a four-blade cascade configuration at an airflow speed of 50 m/s revealed a small but notable noise reduction in the 1–6 kHz range for a partially matched grid–blade geometry. Serrated blades demonstrated an overall sound pressure level reduction of 1.5 dB and up to 12 dB in tonal noise, highlighting the potential of cascade configurations to improve acoustic performance in gas turbine applications.

Development of Flexible Rotor Balancing Procedure Using Response Matching Technique

Abstract Purpose The two main methods under use for balancing of flexible rotor know as Influence Coefficient Method (ICM) and Modal Balancing Method (MBM). It needs few trials to arrive at predicting the unbalance mass. In presence of initial bow along with unbalance these methods will fail to give accurate predictions. It becomes further complex when rotors are mounted on flexible supports. To overcome the limitations of these two methods, a new method called response matching method is disused here for flexible rotor balancing. Method The objective of present work is to develop a balancing procedure for flexible rotor balancing, wherein unbalance response of Finite element model (FEM) is matched with experimental response using iterative technique. Unbalance masses, moments and shaft stiffness of FEM model was iterated to match experimental unbalance responses at three distinct speeds below its first flexural critical speed. Further, unbalances mass was estimated iteratively to cross the bending critical speed with lower residual amplitudes at critical speeds. Results Experimental test setup was developed to validate the proposed method. Results show that present method predicts the unbalance masses and moments to compensate the bow more accurately. Conclusion Results shows that with single run, rotor unbalance masses and movements are predicted accurately. Corrected masses are used in experimental test setup to check the rotor amplitudes during its bending critical speeds. It shows rotor passes first bending critical speed without excessive amplitudes.

An Experimental Study of an Autonomous Heat Removal System Based on an Organic Rankine Cycle for an Advanced Nuclear Power Plant

The present study focuses on the recovery of waste heat in an autonomous safety system designed for advanced nuclear reactors. The system primarily relies on passive safety condensers, which are increasingly integrated into the design of advanced Pressurized Water Reactors (PWRs). These condensers are typically immersed in large water tanks that serve as heat sinks and are placed at sufficient heights to ensure natural circulation. Such a heat removal system can operate for an extended period, depending on the size of the tank. This research is driven by the potential to recover part of the energy stored in the boiling water volume, using it as a heat source for an Organic Rankine Cycle (ORC) system via an immersed heat exchanger. The electricity generated by the ORC engine can be used to power the system components, thereby making it self-sufficient. In particular, a pump replenishes the water tank, ensuring core cooling for a duration no longer limited by the water volume in the tank. An experimental test setup, including a boiling water pool and an ORC engine with an electrical output of approximately several hundred watts, along with an immersed evaporator, was constructed at CEA (Grenoble, France). Several test campaigns were conducted on the experimental test bench, exploring different configurations: two distinct ORC working fluids, cold source temperature variation effects, and relative positioning of the submerged evaporator and heat source within the water tank impact. These tests demonstrated the reliability of the system. The results were also used to validate both the ORC condenser and evaporator models. This article presents this innovative system, which has recently been patented. Moreover, to the best of our knowledge, the investigated configuration of an ORC that includes an immersed evaporator is original.

Measurement of Innovative Green Façades in the Central European Climate

Green structures, such as green roofs or green façades, are great examples of climate change mitigation. Their impact is mainly focused on roofs in the area of overheating reduction. In this paper, initial measurement results of a green façade experimental test setup are provided. The green façade uses an innovative board from recycled materials with vegetation rooted directly on the board. The tested green façade is divided into three segments. These segments differ from each other in their watering regimes, which are crucial for cooling effectiveness. Watering operates with the assistance of gravity; water flows from the top gutter through the boards. In this paper, these three segments are compared to each other with respect to temperatures on the surface of a regular external thermal insulation composite system façade (ETICS) during two summer days. The green façade showed an impact on the temperature in the ventilated air gap, where the temperature is almost the same as the outdoor air temperature in the morning with direct solar radiation on the façade and lower than the outdoor air temperature in the afternoon. At the peaks, the surface temperatures within the air cavity surface are up to 8 °C lower than those on a new white ETICS coating. This demonstrates a cooling potential, although the surface temperatures are always higher than the outdoor air temperatures during daylight hours.

Sensor-Embedded Tissue Phantom for Magnetic Resonance Elastography Mechanical Failure Testing

Abstract Magnetic Resonance Elastography (MRE) is an imaging technique capable of quantifying the stiffness of in vivo tissue by applying and imaging shear waves produced by an MRE actuator. Poor image acquisition may result from the MRE procedure if there is insufficient contact between the MRE actuator and the patient. An experimental test setup outside of the clinic will aid in reducing the number of failed acquisitions by enabling the development of advanced actuators and actuator systems. This work presents the development and testing of a sensor-embedded tissue phantom setup paired with a support vector machine (SVM) classifier to automate the MRE actuator testing process. MRE actuation of soft tissue is simulated by utilizing a voice coil positioning stage that interfaces with a phantom. To capture the resulting vibrations, accelerometers are embedded inside the phantom. Subsequent characterization experiments verify the functionality of the developed phantoms to capture wave propagation. A secondary investigation was performed by utilizing the developed setup to collect acceleration measurements at varying contact distances. We provide an overview of feature analysis and selection to develop SVM models for contact detection. Multiple SVM models are reported, and the best-performing model displayed almost perfect validation (94.53%) and test (90.91%) accuracy. The pairing of sensor-embedded phantom with an SVM for detection demonstrates potential improvements to the MRE actuator developmental process by automatically assessing contact-related issues prior to clinical testing.

MPPT Optimal Torque Control Strategy for a PMSG-based Wind Turbine Emulator

A wind turbine emulator is a valuable tool, which enables real-time physical simulation of a wind turbine behavior using a dedicated experimental test setup, providing a controlled environment for research and development purposes. One significant advantage of using this tool is its ability to test control algorithms designed to maximize power extraction from the wind turbine. This paper continues previous work on developing a small-scale variable-speed wind turbine emulator based on a Permanent Magnet Synchronous Generator for stand-alone applications (Benhacine et al., 2024). This paper presents enhancements made to the emulator. These improvements facilitate the assessment of a maximum power point tracking control strategy designed to optimize power extraction from the wind turbine.

International inter-laboratory comparison of solar heat gain coefficient of building-integrated photovoltaic modules results of tests with or without power generation and tests with PV cell coverage ratios

The solar heat gain coefficient is one of the important indicators to evaluate the performance of the building envelope components. In a BIPV module, secondary heat transfer to the indoors is reduced, compared to conventional glazing, due to the shielding effect of the PV cells and energy conversion by power generation. There is a difference in SHGC between power-generating (MPP) and effectively open-circuit (OC) states. In this paper, in order to prepare a calorimetric SHGC evaluation methodology for BIPV modules, we documented the current status of the experimental calorimetric test methods and test apparatus adopted by test laboratories in four different countries and identified the differences. Differences between the test laboratories were found in to the applied test methods, solar simulator types, spectral distributions, DC or AC power supplies for the solar simulator, irradiation inhomogeneity on the light-receiving surface of the test sample, temperature conditions between the test chamber and the metering box, and surface heat transfer coefficients. Especially, the round-robin test results obtained in an interlaboratory comparison clarified that the differences in the characteristics of the Calorimetic Hot Box and the Heat Flux Metering methodologies with a cooled plate, the differences in irradiation inhomogeneity on the light-receiving surface of the test sample and differences in surface heat transfer coefficients significantly affect the SHGC evaluation for BIPV modules. In addition, for the SHGC test in the MPP state, it was confirmed that an absolute SHGC reduction effect of 0.02 to 0.04 was obtained for a PV laminate with 81 % cell coverage, for all SHGC test methods and test apparatus. Pe characterises the effect of converting part of the sunlight absorbed by the PV cell into electric power and extracting it from the BIPV module, reducing the heat re-radiated indoors compared to the OC state. Due to this mechanism, the reduction effect Pe always occurs during power generation, regardless of the type of PV cell technology and whether the PV cells are opaque or transparent. In addition, the decrease in SHGC for a given glazing configuration was found to be proportional to the increase in PV cell coverage ratio. SHGC tests with four different cell coverage ratios confirmed that the relationship between PV cell coverage ratio and SHGC is linear to a high degree of accuracy when no electric power is extracted (OC state), provided that the incident radiation is spatially homogeneous. The results obtained will be useful when proposing a calorimetric SHGC evaluation methodology for international standardization, as they document the differences due to a range of test facilities and testing conditions, differences caused by power generation and extraction, and the effect of varying PV cell coverage ratios. The insights gained were valuable in identifying which aspects of test methodology and boundary conditions must be specified with particular attention to detail when calorimetric testing standards are extended to explicitly address the SHGC determination of BIPV modules.

The comparative performance study of the EF7 downsized engines; fuel economy besides CO2 reduction

Engine downsizing is considered a strategic idea in fuel economy enhancement as well as reduction. It is defined in the literature as the decrease in engine geometrical dimensions besides its performance being fixed. In this research, the Iranian gasoline-fueled national engine, EF7, has been investigated for 25% downsizing. After introducing the gasoline-fueled and CNG-fueled versions of downsized engines, their performance, besides release rates are studied in detail. A one-dimensional engine simulator coupled with a 3D-CFD model is developed to carry out such an investigation, an experimental test setup is provided to evaluate the accuracy of the provided numerical model, as well. The first version of presented downsized engines, called EF7, is a 3-cylinder engine with the same geometrical characteristics as the base engine, which is equipped with a turbo-charger and dual CVVT technologies. The EF7 is then introduced by fuel shifting to CNG as the second version of downsized engines, and finally, increasing the compression ratio, the EF7 is presented as the third version of studied-downsized engines. The results show almost the same rate of BSFC besides a 3.4% reduction in concentration for EF7, 20.6% fuel economy enhancement, besides 20.8% reduction in the specific release rate for EF7, and 28.8% fuel economy enhancement, besides 25.3% reduction in the specific release rate for EF7 in comparison with the base engine.

Experimental investigation of an off-grid CPC system integrated with a radiator for the application of space heating

Compound parabolic collectors (CPC) are non-tracking concentrators capable of producing lower to medium-range heating (temperature range of 50–80 °C), making them suitable for space heating applications. CPCs raise the heat transfer fluid temperature to a specific value depending upon the solar irradiation received at the location. In this study, CPC is used to harness the solar energy, and an insulated tank is used to store thermal energy. To facilitate space heating, the hot fluid from the thermal storage tank is passed through a radiator, transferring the thermal energy from the tank to the target heating load. The overall setup consists of two loops with water as heat transfer fluid. Both loops consist of a pump that uses solar PV power. An experimental test setup was installed to measure the ambient heat transfer fluid, radiator fin, and room temperature. The combined system was tested for its performance under actual weather conditions prevailing in the area. Experiments were performed to investigate space heating potential at night, evening, and full day. The energy stored and collector efficiency were calculated for each day. The total thermal energy stored in the tank on a typical day was 67.79 MJ, and the collector efficiency was evaluated to be around 43.7 %. As per the experiment results, the combined CPC and radiator system have a significant potential to be explored in space heating.

Advancing sustainable cooling: Performance analysis of a solar-driven thermoelectric refrigeration system for eco-friendly solutions

The solar-powered thermoelectric refrigerator (SPTR) is an innovative approach that uses solar energy to cool spaces. Its effectiveness relies on solar insolation rates and an intelligent dual-axis solar tracking system (STS) that maximizes solar energy capture. Performance analysis of SPTR with the fixed panel solar system (WST) and dual-axis STS by keeping the SPTR at a standard ambient temperature of 25 °C was carried out under local climate conditions. The experimental test setup includes a thermoelectric refrigerator (TER), thermoelectric module (TEM), solar panels, and STS. The experimental findings showed that the coefficient of performance (COP) of SPTR depends on the solar irradiance, the system's input power, the surface temperature of the solar panels, and the cooling rate. The maximum and minimum values of COPs were 1.19 and 0.27 for directly coupled SPTR with a WST and 2.07 and 0.39 for STS, respectively. Compared with the stand-still solar system, a COP enhancement of 44–75 % is achieved. The results also show that the cooling load is a function of the refrigerated space, and the products are to be cooled, which is affected by the thermoelectric properties of the TEM. The cooling rate is recorded at its maximum when the system is operated using an STS on a clear sunny day with a maximum solar insolation rate. The SPTR has proven to be environmentally friendly, the best alternative to conventional cooling systems, and sustainable due to the independence of traditional energy resources.

Development and performance evaluation of active insulation systems using solid-state thermal switches

Traditional building envelopes have passive insulation systems that cannot respond to dynamic changes in the environment. An Active Insulation System (AIS) consists of Active Insulation Materials (AIMs) that dynamically vary the thermal conductivity of the insulation system. Several researchers have evaluated the impact of AIS on building thermal and energy performance by using simulation tools. Up to 70% savings in annual heating and cooling energy and significant reductions in peak demand have been predicted for some climates with wall systems employing AIS. However, materials and assembly development still need a cost-effective product that achieves the required performance. In this study, we present the process of developing an AIS that we will install in a test hut for its performance evaluation. Minimum performance criteria of the AIS system are developed based on R-low/R-high ratio, required time and efficiency to switch states, and cost estimates. The following steps during this study are creating the concept to meet the requirements, predicting the performance via simulations, developing the experimental setup for bench-scale testing, and finally, constructing a full-scale wall assembly and monitoring the performance when exposed to environmental chamber tests. The selected approach uses off-the-shelf products to create an AIS that can switch R-value between 0.98 ft2·°F·h/BTU (0.173 m2·K/W) and 5.81 ft2·°F·h/BTU (1.02 m2·K/W) and have a switching time of less than one minute between R-high and R-low.

Predicting the rutting behaviour of asphalt concrete in the modified wheel tracking test using DEM and a cohesive viscoelastic–elastoplastic-damage contact model

AbstractThis study used an advanced modelling approach capable of capturing the complex behaviour of asphalt concrete to model the modified wheel tracking test using a recent advanced experimental test set-up in accordance with ASTM D8292-20. The modelling approach uses the discrete element method (DEM) to naturally produce the heterogeneous internal structure and governs the behaviour of asphalt concrete at the grain level by an interparticle contact model. The contact model used is capable of characterising the rate and time dependency, viscoelastic-damage, and plastic-damage behaviour of asphalt concrete utilising the coupling of an elastoplastic-damage law with a viscoelastic-damage law. Unlike the conventional wheel tracking tests run in a fixed boundary condition (fully confined), the modified wheel tracking test considers the effect of boundary conditions on the rutting behaviour of asphalt mixes. Through comparisons and verifications with laboratory data of the rutting test at different boundary conditions (fully confined and unconfined), the modelling approach shows its capability of capturing the rutting behaviour of asphalt concrete in the modified wheel tracking test. Micromechanics analysis shows that the third (tertiary) stage of rutting behaviour is due to the weakening of the internal structure of the asphalt samples with contact bond breaks over time, which is found in the unconfined test. Meanwhile, the tertiary stage hardly occurs in the fully confined test once densification leads to contact of the aggregate–aggregate skeleton, forming a rigid structure to resist the load with lateral support from the fixed boundary condition. Finally, a parametric study was also conducted to provide further insight into the current testing set-up, including the effect of the sample size and boundary condition on the rutting behaviour of asphalt concrete.

Experimental validation of a UAS at engine ingestion conditions: Part I Experiments

In recent years, uncrewed aircraft systems (UASs) have greatly increased in popularity and accessibility to the public. This dramatic increase has led to a substantial risk of a midair collision between a UAS and a commercial aircraft, and these collisions need to be analyzed to understand the dangers associated with them. Soft body (i.e., birds or ice) impacts have been happening since the early days of flight and have been studied thoroughly. In contrast, there has been significantly less research on hard body impacts, with most of the currently published research not using experimentally validated models at the conditions expected to be seen in an engine ingestion. The purpose of this work is to discuss the design and execution of experiments to improve and validate a UAS model for high speed impacts for future engine ingestion studies. The overall effort consisted of first conducting physical tests that represent specific high speed ingestion scenarios. Then simulating these tests using a high fidelity finite element tool. Then finally updating the model as necessary. The design of the experiments, experimental test setup, instrumentation and experimental results are highlighted in Part I of this work. The computational model update and validation of the UAS at conditions seen in an engine ingestion are done in Part II of this work.

Computational Fluid Dynamics Process for Front Windshield Mist Deposition and Its Subsequent Demisting

<div>A vehicle’s heating, ventilation, and air-conditioning system plays a dual role in passenger thermal comfort and safety. The functional aspects of safety include the front windshield demist and deicing feature of the system. The thin-film mist is a result of condensation of water vapor on the inner side of the windshield, which occurs at low ambient temperatures or high humidity. This mist deposition depends on the air saturation pressure at the front windshield. Indian regulation AIS-084 defines the experimental setup for testing, which encompasses both the mist deposition and its subsequent demist process. This regulation mandates testing, which occurs at a later stage of product development. This performance validation can be performed using a three-dimensional computational fluid dynamics approach.</div> <div>Current work summarizes the simulation process for both the mist deposition and the subsequent demisting phenomenon. The complexity of the flow physics is captured via the transient multiphase fluid flow phenomenon subjected to buoyancy effects. This phenomenon is simulated using the Eulerian wall film approach. The wall film deposition of the mist is modeled via species transport. Further, the near-wall thermal effects of surface conduction and heat transfer are simulated by modeling shell conduction layers. Vapor diffusion and relative humidity inside the cabin are modeled using a user-defined function. The process correlation is achieved for two categories of vehicles to establish the process efficacy and robustness. Moving ahead, a design of experiments (DOE) is planned to mitigate the need to simulate mist deposition. The DOE is planning to incorporate deviations in both the input airflow conditions and the imposed ambient conditions. The results from DOE point toward factors that might cause deviations in simulation results with respect to the test. Importantly, the study concludes that the uniform initial thickness assumption of the mist layer can be used for subsequent demist analysis.</div>

Novel Concept for the Expansion of the Fibula Bone as an Autologous Bone Graft: Experimental Tests on an Animal Implant Prototype—In Memoriam Volker Buehren

The current reconstructive surgical procedures implemented after the resection of extended bone segments are associated with high complication rates and long-term treatments. By transplanting an autologous, vascularized and stabilized bone segment, these challenges can be managed. Thus, we propose a novel procedure to expand the currently available autologous bone grafts to the dimensions of the recipient bone using an implantable device. The objective of the present study was to characterize the feasibility of developing an implant prototype for fibula expansion in an in vitro model using a porcine fibula. A balloon catheter, as the part of the implant responsible for expansion, was proven to expand while being periodically filled with sodium chloride. Therefore, the expansion of the balloon catheter was analyzed in an experimental test setup with a 3D-printed porcine fibula with a closure film simulating callus formation to simulate the in vivo situation. Our experimental testing proved the successful expansion of the porcine fibula by the balloon catheter. Hence, the feasibility of the concept for subsequent animal testing was confirmed.

Particle swarm optimization for enhanced maximum power point tracking: design and implementation in Proteus

This study introduces a photovoltaic (PV) system model tailored for PV design, incorporating a particle swarm optimization (PSO) MPPT technique to achieve optimal efficiency, swift responsiveness, and cost-effectiveness. To initiate, a PV module model is formulated within Proteus using SPICE coding. Subsequently, an experimental test setup is deployed to authenticate and validate the model. Following this, a PSO-based MPPT algorithm is proposed, which overcomes the limitations of conventional perturb and observe (P&O) and incremental conductance MPPT methods, notably reducing the reliance on mathematical divisions. To substantiate the effectiveness of the proposed approach, both methodologies are implemented on an affordable Arduino Uno platform utilizing the simulated PV module model. The outcomes highlight that the PSO-based MPPT algorithm excels in terms of rapid response (0.09 s), minimal steady-state oscillation, and an impressive 99 percent efficiency.

Numerical Investigation of an Experimental Setup for Thermoplastic Fuselage Panel Testing in Combined Loading

The main purpose of this study comprises the design and the development of a novel experimental configuration for carrying out tests on a full-scale stiffened panel manufactured of fiber-reinforced thermoplastic material. Two different test-bench design concepts were evaluated through a numerical modeling strategy, which will be validated at the next stage using a targeted series of mechanical tests. A baseline experimental setup was developed after a number of candidate configurations were numerically investigated. The supporting elements along with the load introduction systems were defined in such a way as to represent the stiffness of a fuselage barrel section and its representative loading scenarios. The test rig and the investigated thermoplastic panel were numerically simulated to acquire valuable data pertaining to deformations and stresses when subjected to different loading combinations. Two distinct load cases were numerically examined: the first case was the in-plane compression of the thermoplastic panel, while the second case consisted of an internally applied pressure load introduced via an inflatable airbag, installed under the panel. Both loading scenarios were recreated inside the numerical virtual environment in order to examine two distinct stiffening configurations as well as to determine the maximum/limit loads to be used in the planned future experimental campaign. It was concluded that the designed test rig could successfully be used for the structural evaluation of fuselage panels under representative loading conditions.

Virtual Synchronous Machine Control for Asynchronous Grid Connections

The reduced amount of large synchronous generators results in the need for fast, flexible, and intelligent power distribution devices to enhance the inertia in the modern power system. This paper proposes a new approach to control an asynchronous low-voltage grid connection, employing a virtual synchronous machine with frequency-based power control. The grid-forming converter, receiving the primary side frequency measurement, varies the fed grid frequency on the secondary side artificially, to interact with frequency-dependent resources. This enables the adjustment of the consumed or generated power in the fed grid without the need for additional communication infrastructure, and thus supports the frequency control of the mains. The performance of the proposed frequency control has been validated through simulation and using a newly developed double Power Hardware-in-the-Loop experimental test setup.

Single-component Multi-rate Real Time Hybrid Simulation Pilot Test on a Composite Structure

This paper represents a single component multi-rate Real-Time Hybrid Simulation (mrRTHS) strategy for structural assessment of a cantilever Glass Fiber Reinforced Polymer (GFRP) beam loaded at the tip by a sinusoidal point load. This emulated structure is implemented as a simplified wind turbine blade in terms of geometry, scale and load – here with special attention paid to the root and max-chord section. Thus, the experimental substructure comprises the clamped end of the GFRP beam while the free end makes up the numerical substructure. The partitioning between the numerical and experimental substructure – referred to here as the shared boundary – Includes a discrete point with 3 degrees-of-freedom (dof). The numerical substructure generates a displacement signal through a Taylor basis with a coarse time step to optimize computational resources. Using the previous displacement data points, a finer control signal is generated to ensure accurate actuator control in the transfer system. A DIC and inertia compensator is implemented to account for the compliance and dynamics imposed by the load train in the transfer system. The structural response is investigated by mrRTHS for an execution frequency in the range: 0.074Hz – 2.96Hz for the sinusoidal point load. The system performance is evaluated against an experimental test setup of the emulated structure – referred to here as the experimental reference. With a root-mean-square (RMS) error in the order of 8-20% between the mrRTHS and reference, the system proved successful in terms of stability and overall correlation at the shared boundary, which is considered an important milestone towards single component mrRTHS on a structure like e.g. a wind turbine blade, aircraft wing or similar cantilever-shaped large load carrying structure.

Experimental slip determination of upper GFRP-reinforcement in double span beam tests

Despite the impressive features of the steel rebar-reinforced concrete structures, i.e., ductility and rotation capacity, a new material combination has been recently introduced in the new generation of Eurocodes. Glass Fiber Reinforced Polymers (GFRP) rebars were used to replace the steel reinforcements in concrete structures due to their high corrosion resistance and eco-friendly production techniques. GFRP-reinforced concrete could alleviate the environmental issues that affect the durability of the structures, and mitigate the greenhouse gasses which are of great concern nowadays. Indeed, in many design rules of the actual codes, there are implicit (neglecting thermal, settlements, shrink, and creep effects) and explicit (for redistribution purposes) considerations of ductility, which is in general, delivered by the elastoplastic behavior of steel reinforcements. However, this is not the case in the GFRP-rebars where the stress-strain relation exhibits purely linear elastic behavior until failure. Nevertheless, the overall behavior of the GFRP-reinforced concrete structures does not depend only on the behavior of the concrete and GFRP-rebars but also on the bond between the GFRP-rebars and concrete matrix. It is proven that slip of reinforcements can occur which facilitates a more ductile behavior providing the desired ductility and rotation capacity. An experimental test set-up was built consisting of two identical double span (2×1.3 m) beams (0.24×0.30 m²) and two different configurations of upper reinforcement. The slip of the upper and bottom reinforcements was measured along with the applied loads and observed deformations. Hence, the redistribution capacity could be determined, showing the overall ductility of the GFRP-reinforced concrete despite the two main brittle components, i.e., concrete and GFRP-rebars. Results will be used for the revision activities of the new upcoming fib40 publication handling FRP-reinforced concrete structures.