Crack Load Research Articles

Experimental validation of damaged reinforced concrete beam strengthened by pretensioned prestressed ultra-high-performance concrete layer

Strengthening reinforced concrete (RC) beams with ultra-high-performance concrete (UHPC) can improve mechanical properties and durability from previous studies. To further improve UHPC strengthening efficiency, a new technology using a pretensioned prestressed UHPC (P-UHPC) layer for flexural strengthening was proposed in this study. The flexural capacity and crack resistance of the damaged RC beams strengthened by the P-UHPC layer were investigated through a four-point bending test in order for the results to be used in the analysis and design of strengthening damaged structures. The flexural performance of two P-UHPC strengthened beams (PU), one reinforced UHPC (R-UHPC) layer strengthened beam (RU), and one unstrengthened RC control beam (CB) was tested. This study also determined the influence of UHPC shrinkage and prestressing force on the cracking load and ultimate flexural capacity of the P-UHPC strengthened beams by proposing a formal theory. Results showed that the failure modes of the PU beams were typically bending failure. The PU beams showed good composite performance, and there was no debonding failure at the UHPC-RC interface during the test. Moreover, the flexural performance of the damaged RC beams strengthened with the P-UHPC layer was significantly improved, with the average cracking load of the PU beams higher than that of the CB and RU beams by 87.4% and 28.1%, respectively. The average ultimate flexural capacity was 85.2% and 31.7% higher than the CB and RU beams, respectively. In addition, the P-UHPC layer had a more substantial inhibitory effect on the crack development of the damaged RC beams, and the re-expansion load of the cracks in the damaged RC of the PU beams was 111.5 % higher than the RU beam. Finally, the calculation model and theoretical formula for predicting the cracking load and ultimate flexural capacity of the P-UHPC strengthened beams were proposed, and the test results verified the applicability of the proposed calculation methods.

Flexural Behavior of Reinforced Concrete Beams under Instantaneous Loading: Effects of Recycled Ceramic as Cement and Aggregates Replacement

The flexural behavior of five reinforced concrete beams containing recycled ceramic as cement and aggregate replacement subjected to a monotonic static load up to failure was studied. A full-scale, four-point load test was conducted on these beams for 28 days. The experimental results were compared with the conventional concrete as a control specimen. The cross-section and effective span of these beams were (160 × 200 mm) and 2200 mm, respectively. The data recorded during the tests were the ultimate load at failure, steel-reinforcement bar strain, the strain of concrete, cracking history, and mode of failure. The beam containing 100% recycled aggregates displayed an ultimate load of up to 99% of the control beam specimen. In addition, the first crack load was almost similar for both specimens (about 14 kN). The deflection of the beam composed of 100% of the recycled aggregates was reduced by 43% compared to the control specimen. Regardless of the recycled ceramic aggregates ratio, quantities such as service, yield, and ultimate load of the proposed beams exhibited a comparable trend. It was asserted that the ceramic wastes might be of potential use in producing high-performance concrete needed by the structural industry. It might be an effective strategy to decrease the pressure on the environment, thus reducing the amount of natural resources usage.

Structural Behavior of High Strength Arched Reinforced Concrete Slabs

In the past, the arch represented one of the few structural systems which provide a possibility to cover large spans. Nowadays, the same importance is presented as the need increased with the increase of construction with large spans and with arched structures which are constructed in different shapes and from various materials such as brick, steel and reinforced concrete. The main aim of this study was to investigate the behavior and ultimate strength of concrete arched slab under flexural load. The main parameters considered in the present investigation are, concrete mix compressive strength, thickness of slab, area of steel, curvature and support conditions. A total of fourteen samples of the arched slab are constructed and tested under two-point load. The behavior of the samples is observed by reading the deflection at mid-span and observing the crack patterns and strains at top and bottom fibers. The behavior of arched slab samples is linear up to first cracking load and still linear up to (35% - 55%) from the ultimate load. The load-deflection curve at mid span of the arched slab may be idealized by bilinear curve. The increasing of compressive strength by 116% leads to increase the ultimate load by (15% - 25%). Increasing the slab thickness by 43% leads to increase the ultimate load by (6% -17%). Increasing the area of steel by 45% leads to increase the ultimate load by (29% - 34%). Increasing the curvature by 200% leads to increase the ultimate load by (6% - 28%). Changing the support from simply support to pin-pin leads to increase the ultimate load by (200% - 245%).

Multi-factor sensitivity analysis of chloride ingression: A case study for Hangzhou Bay Bridge

The transport of chloride into concrete is affected by many factors, including temperature, relative humidity, load cracks, and material properties. The purpose of this paper is to analyze the influence of various factors on the chloride ingression process through a case study for Hangzhou Bay Bridge located in marine environment. Firstly, based on the concentration of free chloride in pore solution, a porous media diffusion model is derived, considering the chloride adsorption term. Then, chloride adsorption isotherm, time-varying diffusion coefficient, temperature, relative humidity, and macroscopic cracks are simulated respectively by the porous media diffusion model. The main conclusions are as follows: (1) The chloride adsorption effect and time-varying diffusion coefficient have a great influence on the numerical results, which cannot be ignored in any case. (2) The natural temperature and relative humidity conditions of the case have a small effect on the simulation results. (3) Under the marine atmospheric environment, the macroscopic load cracks have a small influence on chloride ingression in the long term.

Influence of boron addition on the phase transformation, microstructure, mechanical and in-vitro cellular properties of bredigite-type coatings deposited by a spin coating technique

Doped calcium silicates, e.g. bredigite (Ca7MgSi4O16) have recently become a growing interest in biomedicine thanks to outstanding biocompatibility, bioactivity, and improved mechanical properties when compared to calcium phosphate counterparts. Here, we have produced thin bredigite-type coatings on Ti6Al4V substrate by the polyvinyl alcohol (PVA) assisted sol-gel spin-coating technique and studied the influence of boron incorporation (0.5 and 1.0 mol) on the microstructural, phase, nanomechanical, and in-vitro cellular properties of deposited coatings. Chemical and structural analysis of the coatings was thoroughly performed by Focussed Ion Beam Scanning Electron Microscope (SEM/FIB), Atomic Force Microscopy (AFM), differential thermal analysis (DTA-TG), X-ray diffraction (XRD), and Fourier-Transform Infrared spectroscopy (FTIR), while the nanomechanical properties were evaluated by nanoindentation and nanoscratch tests. Overall, all deposited films were smooth and porous composed of ∼25–50 nm nanoparticles. The boron incorporation increased the coating thickness as a result of PVA interaction with borate ions. The nanomechanical properties (Young's modulus, nanohardness, critical load for cracking) decreased by the boron addition as a result of decreasing the strength of grain boundaries between the nanoparticles. The in-vitro contact cytotoxicity testing revealed high proliferation of the osteoblast cells in all coatings giving the potential of application in orthopedics.

Quasi-Static Test Study on Seismic Behavior of Large-Section Fabricated Utility Tunnel

Based on the urban utility tunnel project in Xiong’an New Area, to clarify the seismic behavior of the utility tunnel structure, the overall structure model of the four-cabin large-section utility tunnel and the quasi-static test of the joint specimens have been completed. The results show the following. (1) The hysteresis curve of the overall structure is relatively full, showing good ductility and energy consumption. The middle joint has better bending performance. The ductility of the side joint is worse than that of the middle one. (2) The skeleton curve of the joint specimen is divided into three stages: obvious cracking, yielding, and ultimate load. After the overall structure reaches the ultimate load, the load curve basically tends to be horizontal. (3) The stiffness degradation of the overall structure and the joint specimens continues to be uniform during the entire loading process. (4) The structural design of the fabricated utility tunnel can ensure the seismic behavior under normal condition.

The Effect of the Concrete Elimination Ratio on The Structural Behavior of Bubbled Reinforced Concrete Slabs

This investigation focuses on the impact of the concrete elimination ratio on the structural behavior of bubbled reinforced self-compacting concrete (SCC) slabs. Construction and testing of eight bubbled slab specimens with dimensions of 45x45x80mm are part of the experimental program. The specimens are separated into two categories. The first set of four specimens is used to explore the effect of removing regular strength SCC from concrete, while the second group is used to investigate the effect of removing high strength SCC from concrete. According to the results of the experiments, increasing the number of balls in a typical strength SCC reduces the first fracture load from 8.3 % to 15.5 % and the ultimate load from 3.98 % to 12.15 %. The experimental results indicated that the change of No. of balls for high strength SCC decreases the first crack load from 2.5% to 8.92% and decreases the ultimate load from 5.95% to 16.19%. Also increase the No. of balls, it notes reduced the slab stiffness.

Structural Performance of Reinforced Concrete Beams with Various Cross-Section

The deflection of reinforced concrete beams with various cross-sections was investigated in this work. The experimental program comprised of four reinforced concrete beams that were simply supported. They were put through a two-point load test. High to width ratio (h/b) was (0.36, 0.64, 1, and1.56), concrete compressive strength was from 27 MPa. The gradual increase in the (h/b) ratio (from 0.36 to 0.64, 1 and 1.56) with (27 MPa) compressive strength of concrete leads to increase the first crack load for the (N2, N3 and N4) by (74%, 111% and 122%) respectively as compared with (N1), the beams (N2, N3 and N4) exhibits an increase in the yielding load by (41.2%, 70.6% and 64.7%) respectively as compared with (N1), increase the ultimate load by (25% - 130%). The ductility index is reduced with gradual increase in the (h/b) ratio (from 0.36 to 0.64, 1 and 1.56) for (27 MPa) concrete compressive strength by (1.2% - 25.5%). For the beams (N1, N2, N3 and N4) it is noticed that the central deflection of the four beams reduced gradually at the same load with increase in the (h/b) ratio from (0.36 to 0.64, 1 and 1.56) with constant (27 MPa) compressive strength concrete. The maximum crack width decreases gradually with gradual increase in the (h/b) ratio (from 0.36 to 0.64, 1 and 1.56) for constant (27 MPa).

Analytical Modeling of Crack Widths and Cracking Loads in Structural RC Members

Crack width is a major performance criterion in reinforced-concrete structures, in general, and is of utmost importance in ensuring bridge performance, in particular. A reliable theory-based method is required to assess crack widths and gain insight into their dependence on material, geometry, and loading parameters. A new, exact analytical method is proposed for a one-dimensional reinforced concrete element based on equilibrium, constitutive, and kinematic relationships, accounting for the geometrical and material behavior of the concrete and reinforcement. A linear interfacial bond stress slip is assumed to represents the small slips associated with the limited allowed crack width. Closed-form expressions have been developed and a wealth of information can be calculated immediately, such as the cracking load levels, the crack width dependence on the load level, the expected number of cracks, and the cracks spacing. The entire nonlinear force-displacement relationship of a cracked reinforced-concrete element may be depicted, demonstrating the tension-stiffening behavior that depends on the variations in the crack width throughout the loading history. Comparisons of the model with experimental data demonstrate very good agreement.

Crack Propagation Assessment of Time-Dependent Concrete Degradation of Prestressed Concrete Sleepers

As prestressed concrete sleepers are continuously exposed to various environmental and loading conditions, it is increasingly crucial to analyse their current and future serviceability performance. In practice, the main cause of cracking in prestressed concrete sleepers is usually induced by impact loads. The most heavily influenced sections are the midspan and rail-seat area of sleepers. This paper investigates the effects of time-dependent concrete strength degradation on the capacity of prestressed concrete sleepers. The factors affecting concrete strength degradation are analysed in order to evaluate the crack behaviour of prestressed concrete sleepers. A finite element modelling approach is developed for prestressed concrete sleepers, which is used to assess the effects of structural behaviour in railway sleepers. The sleeper model has been calibrated and validated. This research firstly discusses time-dependent behaviour using load–crack length responses. It is shown that various cracking modes cause an overall increase in the maximum cracking length as prestressed concrete sleepers age. This paper demonstrates that initial cracking loads and ultimate crack lengths have significant change in first 20 years. After 40 years of service life, the crack resistance of prestressed concrete sleepers becomes very weak which is only 61.32% of the new sleeper. In long term, the initial cracking load keeps reducing, and the crack propagation rate becomes sharp. The presented methodology and results can greatly assist in decision-making for the repair or replacement of prestressed concrete sleepers and aid in the design of new prestressed concrete sleepers considering their future performance.

Seismic behaviour of cross vaults with different brick pattern

Cross masonry vaults are common structural elements in historical buildings. They are largely diffused in all European countries, including those characterized by higher levels of seismicity. Although they have been constructed for centuries, they represent some of the most vulnerable elements of traditional architecture, especially with reference to horizontal loads. The understanding of their structural behaviour under seismic loading is a crucial aspect for the accurate assessment of the safety of historical buildings. In the present work, the seismic response of cross masonry vaults is analysed through the Finite Element Method (FEM) and static non-linear analyses considering the effect of different brick patterns and boundary conditions. A simplified micro-modelling approach is adopted for the generation of the FEM models and two different brick arrangements are considered, i.e., radial bricks and diagonal bricks, which are the most widespread in European cross vaults. Two different boundary conditions are assumed in order to simulate a vault with and without lateral confinement. Static non-linear analyses are performed by monotonically incrementing a lateral acceleration until collapse. Results are analysed in terms of maximum load factor, stiffness, ductility, crack pattern and damage mechanisms. The analysis of the results shows that not only boundary conditions, but also the brick pattern strongly influences the vault seismic response both in terms of stiffness and ductility as well as in terms of global capacity.

SHEAR BEHAVIOR OF FIBROUS REINFORCED CONCRETE WIDE BEAMS

When a reinforced concrete beam does not have enough shear strength and / or little amount of secondary rebar are reinforced, the "shear failure" is possible. Such type of failure is not acceptable in civil engineering due it does not indicate any prior notice before the complete failure of the intended structural member. One of the most popular solutions to overcome such shortcoming is the addition of steel fibers due to the ability for enhancing mechanical properties and ductility. Wide beams are such beams that have high width if compared with its thickness, such structural members are frequent in many reinforced concrete building systems and may also face "shear failure" during its service life. The current study investigates the structural behavior of the Steel Fiber Reinforced Concrete Wide Beams by proposing an experimental program comprising casting and testing of twenty beams specimen. The effective shear spans to depth ratio ratios were 2.5 and 3.5, respectively. Two nominal strength levels 30 MPa "Normal strength concrete" and 60 MPa "High strength concrete are also included. The types of steel fibers used are the "End Hocked" as well as the "Staggered" in 0.5% and 1.5% volume fractions for each one. The results showed that the addition of steel fibers enhances the consequent mechanical properties and the relevant structural behavior of wide beams to a serious concern. Furthermore, the addition of steel fibers modified the shear failure mode to "flexural". The first cracking load increased in "Normal strength" from 21.95% to 73.73% by adding "End Hocked" and from 12.19% to 45.45% by adding "Staggered" while such range reported 15.95% to 45.76% for "End Hocked" and 7.25% to 28.81% for "Staggered" in "High strength". Additionally, the ultimate load increased in "Normal strength" from 19.75% to 65.98% by adding "End Hocked" and from 10.52% to 43.81% by adding "Staggered" while such range reported 13.5% to43.57 % for "End Hocked" and 7.25% 29.29to % for "Staggered" in "High strength".

Experimental study on corrugated steel–concrete composite semicircular arches under midspan loading

Corrugated steel–concrete composite arch is a novel structural form that increases the load-bearing capacity of corrugated steel (CS). In this study, the static performance of a CS-plain concrete (CSPC) semicircular arch and CS-reinforced concrete (CSRC) semicircular arch was experimentally investigated under midspan loading using six arch specimens. The performance of four CSPC arch specimens with different bond strengths and concrete strengths was tested and compared. The results showed that insufficient bond strength between CS and concrete caused concrete breakout failure and affected the ultimate bearing capacity significantly, with the largest reduction of 62%. Therefore, adopting a high concrete strength can significantly improve the concrete cracking load and bearing capacity of CSPC arches. Subsequently, a CSRC arch was also tested, together with a reinforced concrete (RC) arch, to investigate the failure mode and ultimate bearing capacity. It was found that because of the high moment of inertia and contribution of the CS to the shear strength, the stiffness and ultimate bearing capacity of the CSRC arch were higher by 86% and 90%, respectively, than that of the RC arch with the same amount of concrete and steel. In addition, based on the measured strain, composite and confining effects were observed in the CSRC arch; however, the confining effect was negligible.

Nonlinear Finite Element Structural Analysis of Reinforced Concrete Beams with out of Plane Parts

The purpose of this study was to investigate and compare the structural behavior of the reinforced concrete beams contain out of plane parts with the straight beam by finite element analysis (FEA) using ABAQUS software package. The studied models were evaluated by comparing their results with previous experimental results of the research done by the same authors. The study focused on the effects of the number of the out of plane parts on the beams' mid span deflection, the cracking and ultimate loads, and failure mode. The obtained results showed that load bearing capacity of the beams with one, two, and three out of plane parts was lower than the capacity of the straight beam by about 35%, 33%, and 68%. In addition, the results of the beams with an even number of out of plane parts were generally better than the results of those with odd number, and the increasing number of out of plane parts changed the failure mode from flexure to combined flexure plus torsion. Finally, the FEM analysis was comparable with those obtained from the experimental procedures with an average difference ratio not exceeding 5% in the ultimate load and 7% in the deflection.

Analysis of computational fluid dynamics (CFD) on fiber reinforced self-compacting concrete

An experimental and CFD analysis of self-compacting concrete uses quarry dust and various partial flea ash substitutes, silica fumes, and both flea ash and silica fume combinations to construct a finely-structured polypropylene reinforced concrete beam. Using three different fractions of fiber volume, this article investigates the influence of polypropylene fibers on self-compacting concrete beams (2.0 percent, 2.5 percent and 3.0 percent). The M30 grade was taken into consideration. This study employed a computational fluid dynamics tool to model the experimental beam and failure scenarios. The three-dimensional CFD technique method used to model concrete beams has proven to be a reliable predictive tool for concrete beam analysis. However, when performing non-linear CFD analysis, it is critical to select appropriate finite elements and the correct mesh density in order to obtain a satisfactory solution to the problem. Furthermore, it has been discovered that linear regression may provide a good forecast of first crack load, deflection at first crack load, yield load, deflection at yield load, ultimate load, deflection at ultimate load, and ultimate load, deflection at ultimate load. There is a high level of agreement between the forecast and the test findings.

Rehabilitation of partially damaged high strength RC corbels by EB FRP composites and NSM steel bars

In this study, a comparison has been done between the efficiency of repairing of partially damaged high strength self-compacting RC corbels using two techniques, namely are NSM steel bars and CFRP sheets. The experimental program consists of testing eleven specimens, one of which acted as a control corbel (without repairing) and the other ten are upgraded using several configurations of alignment with two damage levels (45% and 65%). The response has been discussed in terms of the first cracking load, ultimate load, maximum deflection, failure mode, loading history, crack pattern, toughness value, and ductility index. Results revealed that the NSM steel bars technique could be adopted as an adequate method within the early levels of damage whereas the EB CFRP sheet is more suitable for largely damaged corbels. Moreover, results revealed that NSM technique with the inclined, horizontal, and combined alignment yielded enhancements in ultimate load capacity of 98.6%, 55.1% and 74.2%, respectively for a damage level of 45% and 24%, 50% and 19% for damage level of 65%, respectively. Whereas, the corresponding improvement using the CFRP sheet with damage level of 45% are 52% and 50% for specimens repaired using horizontal and diagonal CFRP sheet, respectively. The respective values are 71%, 38% for damage level of 65%.

Finite Element Analysis of Reinforced Concrete Beams Strengthened with Carbon Fiber Reinforced Polymer Sheets

This paper presents outcomes of extensive research conducted to study the behavior of reinforced concrete (RC) beams strengthened with CFRP sheets and subjected to shear and flexural loading. A 3-dimensional Finite Element(FE) modelling was carried out using ABAQUS software program to simulate the flexural and shearing behavior of a number of RC beams strengthen with CFRP. Moreover, the results of the numerical simulation were compared with actual results of experimental physical modelling of RC beams subjected to the same loading conditions for validation purpose.Appreciable number of sets of control RC beams and CFRP strengthened RC beams for flexural and shear were investigated. All beams were rectangular in cross section. To accurately describe the behavior of these tested RC beams, different material constitutive models were used in the simulation. Concrete damaged plasticity model was used to model concrete;a linear elastic perfectly plastic model was used to model both reinforcing steel and stirrups, while a linear elastic isotropic model was used to simulate the behavior of CFRP material. Moreover, the interface between concrete and CFRP material was accounted for and was simulated using a tie perfect bond model while steel reinforcement is bonded with concrete as anembedded element in ABAQUS. A careful comparison between the results of the experimental tests and those of the numerical simulation showed that the proposed FE model is able to describe the behavior of reinforcedconcrete beams strengthened with CFRP in terms of crack pattern and load deflection curves to an appreciable level of accuracy. Generally, the results demonstrate that numerical approach can be used to deeply investigate thebehavior of RC beams strengthened with CFRP sheets. It was also concluded that the numerical approach was able to capture significant aspects of structural behavior of the tested beams such as strain distribution in CFRP, which is often not easily captured experimentally or analytically.

Experimental and Numerical Study on the Failure Characteristics of Brittle Solids with a Circular Hole and Internal Cracks.

A stress analysis of a circular hole is one of the classical problems in mechanics. Internal cracks are inherent properties of materials, and they are mostly three-dimensional in form. However, studies on hole problems with three-dimensional internal cracks are still lacking. In this paper, internal cracks were generated in brittle materials containing circular holes based on 3D internal laser-engraved crack technology. Then, uniaxial compression tests were performed. The experimental results were compared with the existing literature, and theoretical and numerical simulation studies were carried out. The results show that: (1) The main crack shapes are the primary cracks and remote cracks. (2) The dynamic fracture characteristics existed in the formation of primary cracks and the surface of remote cracks. The tips of primary cracks were arc-shaped, and the surfaces of the remote cracks were curved. Remote cracks were tangential to the orifice where type III spear-like characteristics appeared. (3) The stress birefringence technology can be combined with 3D internal laser-engraved crack technology for internal crack stress information monitoring, the moire around the orifice was “flamboyant”, and the moire at the tip of the prefabricated crack was “petallike”. (4) The existence of internal cracks reduced the cracking and breaking load of the specimen, and compared with the intact orifice specimen, the upper primary crack, the lower primary crack, the remote crack and the failure load were reduced by 41.2%, 31.7%, 15.9%, and 32.3%, respectively. (5) The results of qualitative stress analysis of the orifice specimen were consistent with the initiation law of primary cracks and remote cracks. The K distribution based on M integral and the numerical simulation of crack propagation process based on the maximum tensile stress criterion were consistent with the law of primary crack growth. Compared with the current mainstream method of transparent rock research, 3D internal laser-engraved crack technology has certain advantages in terms of brittleness, crack authenticity, stress field visualization, and fracture characteristics, and the result will provide experimental and theoretical references for research on three-dimensional problems and internal cracks in fracture mechanics.

Flexural Behavior of RC Beams Using Fe-Based Shape Memory Alloy Rebars as Tensile Reinforcement

Recently, various studies for the use of Fe-based shape memory alloy (Fe-SMA) in the construction field have been widely conducted. However, most of the studies for using Fe-SMA are carried out for applying Fe-SMA for strengthening deteriorated structures. However, if Fe-SMA is used as a reinforcement for new structures, the disadvantages of conventional prestressed concrete can be effectively solved. Therefore, in this work, an experimental study was conducted to evaluate the flexural behavior of concrete beams in which Fe-SMA rebars were used as tensile reinforcement. For the study, ten specimens were constructed with the consideration of the cross-sectional area and activation of Fe-SMA rebars as experimental variable. Activation of the Fe-SMA rebars by electrical resistance heating applied an eccentric compressive force to the specimen to induce camber. The camber increased by an average of 0.093 mm as the cross-sectional area of the Fe-SMA rebar increased by 100 mm2. It was also confirmed through the four-point bending tests that the initial crack loads of the activated specimens were 47.6~112.8% greater than those of the nonactivated specimens. However, the ultimate strength of the activated specimens showed a slight difference of 3% to those of the nonactivated specimens. Therefore, it was confirmed that the effect of Fe-SMA activation on the ultimate strength of specimens was negligible.

Evaluation of slag/fly ash based geopolymer concrete with steel, polypropylene and polyamide fibers

Geopolymer composites have become an essential product to reduce CO2 emissions, which is an important problem today and ensures green sustainability. With the increasing concerns with global climate change, studies on geopolymer have also increased. The addition of different fibers also has essential potential for increasing the performances of geopolymer composites. Within the scope of this study, it is aimed to produce a green sustainable product as an alternative to traditional concrete by producing different fiber-reinforced geopolymer concrete. In this study, slag-fly ash-based geopolymer concretes reinforced with three different fiber types (Polypropylene (PP), steel (ST), and polyamide (PA)) were produced and the mechanical properties such as compressive, tensile, drying shrinkage and flexural behavior were investigated. Furthermore, elevated temperature (300, 600 and 900-celsius degrees) and freeze-thaw (250 cycles) tests were carried out within the scope of durability properties. Microstructural analyzes were also carried out to understand the matrix composition. Experimental test results revealed that fiber reinforcement improved some of the strength properties, but was ineffective for some properties. The addition of polypropylene and steel fibers significantly improved the flexural toughness factor value (1469% and 566%, respectively) of geopolymer concretes, while this rate of improvement remained quite low (46%) in the polyamide fiber reinforced geopolymer series. According to shrinkage test values, 50S50FA08ST sample ranged from 264 to 297 microstrains. Also, PP fibers increased the initial crack load from approximately 4500 N to 6750 N and the deflection values significantly improved by reaching the deflection values of 7.5 mm. Moreover, the compressive strength values after 900 °C was obtained as 11–12 MPa for steel fiber reinforced geopolymer concretes. But the freeze–thaw experiments generally revealed that fiber addition did not contribute to the improvement of strength properties.