Portland Cement Concrete Specimens Research Articles

The Behavior of Ceramic Fiber Geopolymer Concrete under the Effect of High Temperature

Geopolymer concrete (GC), also known as green concrete, contains slag, silica fume, and fly ash as binders. The absence of cement in concrete is critical to protect the world from the environmental impacts of cement production. In addition, exposure to high temperatures is a critical parameter that causes loss of strength in concrete. In this study, Geopolymer concrete samples were prepared with 10 different samples containing different proportions of slag, silica fume, and porous ash and subjected to various physical, mechanical, and optical tests. The sample (GS90) with optimum workability and compressive strength, which also showed high performance in water absorption, freeze-thaw, and UPV tests, was used in high-temperature tests. Portland cement concrete (PCC) was used as a control sample. This study investigated the effect of high temperatures on the physical and mechanical properties of fiber-free GCs containing 2%, 5%, and 10% by volume of ceramic fibers. Therefore, fiber-reinforced, fiber-free, and PCC specimens were subjected to high-temperature tests at 100, 300, 600, and 900 °C. As a result of the observation of crack growth, color changes, and compressive strength parameters in the samples subjected to high-temperature tests, the thermal resistance of the 10% ceramic fiber geopolymer concrete sample was 2.5% higher than other samples. There is no study in the literature that examines the behavior of ceramic fiber-reinforced geopolymer concrete at high temperatures. This research revealed an important finding by proving that ceramic fiber reinforcement increases the compressive strength of geopolymer concretes at a remarkable rate after high-temperature impact.

Bond performance of steel rebar in alkali-activated slag-based concrete after exposure to elevated temperature

Bond strength deterioration between reinforcing bars and surrounding concrete is critical to structural performance loss during a fire. However, available studies on the bond behavior between alkali-activated concrete and reinforcing bars at elevated temperatures are insufficient. This study conducted pull-out tests on alkali-activated slag-based concrete (AAC) specimens with three concrete strength grades (C30, C50, and C70) and rebar diameters (14, 18, and 22 mm) at ambient temperature and after exposure to 200, 400, 600, and 800 ℃. The experimental and analytical results showed that AAC pull-out specimen using normal-strength concrete was more prone to splitting failure than Portland cement concrete (PCC) specimens and required greater lateral confinement. The absolute and relative values of residual bond strength for AAC and PCC specimens after high-temperature exposure were similar, which corresponds to their similar thermal degradation of concrete strength. After exposure to 200 ℃, 400 ℃, 600 ℃ and 800 ℃, their rebar bond strength declined rapidly to about 80%, 50%, 15%, and less than 10% of their respective bond strength at ambient condition, respectively. Compared with the counterpart PCC specimens, AAC specimens exhibited greater peak slip and relatively smaller bond stiffness after exposure to elevated temperature due to smaller elastic modulus of AAC. Further, the concrete strength and concrete cover-to-rebar diameter ratio have a significant effect on the failure mode and residual bond strength of AAC pull-out specimens. To evaluate the residual bond property of reinforced AAC after exposure to elevated temperature, an empirical model of bond strength versus temperature and a simplified bond-slip constitutive equation were proposed.

Impact of freeze-thaw environment on concrete materials in two-lift concrete pavement

The freeze-thaw (FT) damage is a potential severe distress on concrete pavements in seasonal frozen regions. This study focuses on the FT resistance of a two-lift concrete (2LC) pavement, including a polypropylene fiber reinforced concrete (PFRC) top lift and a conventional portland cement concrete (PCC) bottom lift. The rapid FT test was conducted on PCC, PFRC, and 2LC specimens and the relative dynamic modulus and mass loss were measured. The mechanical properties of concrete materials were investigated in laboratory, including compressive, tensile, flexural strengths, and flexural modulus. In the end, the influence of FT damages of concrete materials on pavement responses was evaluated. It is found that with the addition of the PF, the PFRC and the 2LC exhibited better mechanical properties and less mass loss than the PCC after FT cycles. The PFRC and the 2LC behaved better FT resistance than the PCC. The Voigt model can predict mechanical properties of 2LC in freeze-thaw process. Through pavement response analysis, the FT damage was found shortening the service life of 2LCP. In summary, the proposed 2LC pavement was justified a better alternate concrete pavement type on resisting the FT environment in seasonal frozen areas.

Evaluation of the Impact Echo Method for Concrete Bridge Decks with Asphalt Overlays

Asphalt overlays have been commonly used to extend the service life of deteriorated concrete bridge decks. Nonlinear, viscoelastic asphalt has properties that differ considerably from the properties of the underlying portland cement concrete (PCC) deck. The impact echo (IE) method has been extensively used to nondestructively evaluate PCC structures. The method, however, performs differently on asphalt overlays, especially when a membrane is placed between the overlay and the deck. The general recommendation has been to perform IE tests on asphalt overlays in cold weather. The temperature range under which IE can be used, however, is still uncertain. This study was conducted to systematically examine IE performance on asphalt overlays. Three PCC specimens with three types of asphalt overlays―asphalt with a liquid membrane, asphalt with a sheet membrane, and asphalt without a membrane―were tested in a temperature chamber. The three PCC specimens had identical designs, materials, and artificial defects. The nondestructive evaluation (NDE) results from the tests indicate that: (1) 32°F and below is the appropriate temperature range for IE to detect defects in the underlying deck; and (2) membranes can significantly reduce the propagation of waves into the underlying deck.

Dispersion of Multi-Walled Carbon Nanotubes in Portland Cement Concrete Using Ultra-Sonication and Polycarboxylic Based Superplasticizer

The potential properties of carbon nanotube-cement based materials strongly depend on the dispersion of carbon nanotubes (CNTs) within the cement matrix and the bonding between CNTs and the hydrated cement. The homogeneous dispersion of CNTs in the cement matrix yet is one of the main challenges due to strong van der Waals forces between nanotubes. In this study, a polycarboxylic ether based superplasticizer and ultra-sonication technique was used for dispersion of multi-walled carbon nanotubes (MWCNTs). Portland cement concrete specimens with different concentrations of MWCNTs (0.04 and 0.1 % by the weight of cement), with and without the presence of superplasticizer were investigated. Compressive strength test results revealed a significant improvement in mechanical properties of sample containing 0.1 % MWCNTs and 0.2 % superplasticizer. Moreover, field emission scanning electron microscopy (FESEM) images of fractured surfaces of hardened specimens showed a good dispersion of MWCNTs within the cement matrix. This method was developed to facilitate the uniform dispersion of MWCNTs in the cementitious concrete for better reinforcement in nanoscale and mechanical properties enhancement by transfer of load between the nanotubes and matrix.

Experimental Validation of a Numerical Model for Simulating Radiographic Imaging of Portland Cement-Based Materials

This paper presents a numerical modeling approach, developed within the CIVA RT virtual radiography software, for simulating radiographic imaging of Portland cement-based materials. The modeling approach is validated experimentally for 20 and 30 cm thick Portland cement concrete specimens, which were imaged over a range of source intensities using a 450 keV COMET MXR-451 X-ray tube. Both a discrete coarse aggregate (DCA) model and a computationally efficient homogenized concrete (HC) model were investigated. The study found that for concrete sections thicker than 10 cm, the HC model provides radiation transmission predictions comparable to the DCA model, which was attributed to the increase in photon scattering with specimen thickness. The experimental validation study utilized film-based radiography and considered target optical density measurements of 1.0, 2.0, and 3.5. In general, numerical predictions from the virtual radiography model were in good agreement with the experimental data. For the 20 cm thick specimens, relative error in the numerical predictions ranged from 18 to 20 %. Relative error in numerical predictions for the 30 cm thick specimens ranged from 4 to 8 %. The improvement in model prediction accuracy for the thicker specimens was attributed to increased filtration of lower energy radiation, which reduced the influence of approximation error in the lower energy region of the photon emission spectrum.

Recycling MSTP Sludge as an Admixture in Concrete

One of the main objectives of this study was to activate the pozzolanic activity of sludge, produced by municipal sewage treatment plants (MSTP), make it become an admixture to replace a part of cement in concrete. Nowadays, a significant quantity of MSTP sludge is obtained in China. That is why this paper examines the possibility of adding this waste product to plain concrete with Portland cement. Preliminary studies are carried out on using MSTP sludge as an admixture by thermal (calcining) and mechanical (grinding) treatment. The pozzolanic activity of the calcined sludge ash (CSA) evaluated by Cement Mortar test. The CSA-blended cement concrete was formed into specimens of cubic concrete with 100 mm×100 mm×100 mm. They are with 30 wt. % cement replaced by CSA, which was prepared by the optimal activation conditions. The Cement Mortar test results revealed that the optimal activation conditions of CSA were as follows: calcined at 800°C for 2.5 hours followed by fast cooling in air and then ground until 60 minutes. Besides, the compressive strengths of concrete specimens with added 30% CSA were 103.6% and 105.3% of those of the ordinary Portland cement concrete specimens at 7 and 28 days, respectively. These results demonstrate the feasibility of recycling MSTP sludge as an admixture in concrete for construction engineering.

Cement Stabilization of Conventional Granular Base and Recycled Crushed Portland Cement Concrete

Challenges in finding high-quality sources of natural aggregate have led Saskatchewan, Canada, road agencies to explore alternative solutions to meet aggregate demands. The use of recycled materials, such as recycled portland cement concrete (PCC), though traditionally limited to low-quality applications such as subbase or backfill materials, shows promise as a technically viable solution that also offers economic and environmental advantages. In this study, mechanistic material testing was used to examine the effects of cement stabilization on traditional granular base and on two impact-crushed recycled PCC materials from different locations. The unstabilized PCC materials had substantially better mechanistic material properties than the unstabilized conventional granular base material; this result indicates that PCC materials could be suitable for use in high-quality applications, such as base course layers, rather than being limited to use in low-quality applications, such as utility and embankment fills. This study also showed that cement stabilization substantially improved the mechanistic properties of conventional granular base material, yet had a much less pronounced effect on the material properties of the PCC materials. This result may be attributable to poor absorption of the cement by the PCC or a lack of rehydration of the PCC. There was minimal variability in the mechanical behavior of the PCC specimens despite a difference in stockpile location. Both types of PCC material were processed and crushed with the same technique and equipment.

Effects of w/c ratio on Portland limestone cement concrete

Hitherto, limestone has been recognised as a suitable substitute for cement replacement. The present study was an experimental investigation of the properties of Portland limestone cement and the effects of water-to-cement (w/c) ratio on performance of concretes containing it. The Portland limestone cement concrete specimens (containing 14% limestone) with w/c ratio of 0·35, 0·45 and 0·55 were experimentally compared to ordinary Portland cement concrete specimens. The results demonstrated that w/c ratio has a prominent effect on the performance of Portland limestone cement concretes, with higher w/c resulting in weaker performance. Therefore Portland limestone cement containing 14% limestone can be considered as a low-cost, effective and available supplementary cementing material.

Freeze–thaw damage and chemical change of a portland cement concrete in the presence of diluted deicers

The present study experimentally investigates the effect of different diluted deicers on concrete deterioration. Laboratory simulations of environmental freeze/thaw cycling were first conducted on Portland cement concrete specimens in the presence of various deicers (NaCl, K-formate, NaCl-based deicer, K-acetate-based deicer, Na-acetate/Na-formate blend deicer, CMA deicer, or MgCl2 liquid deicer); and SEM/EDX measurements were then conducted for the concrete samples. Under the experimental conditions in this study, the CMA solid deicer and the MgCl2 liquid deicer were benign to the concrete durability, whereas K-formate and the Na-acetate/Na-formate blend deicer showed moderate amount of weight loss and noticeable deterioration of the concrete. NaCl, the NaCl-based deicer, and the K-acetate-based deicer were the most deleterious to the concrete. In addition to exacerbating physical distresses, each investigated chemical or diluted deicer chemically reacted with some of the cement hydrates and formed new products in the pores and cracks. Such physiochemical changes of the cement paste induced by the deicers pose various levels of risks for the concrete durability.

Long-Term Effects of Magnesium Chloride and Other Concentrated Salt Solutions on Pavement and Structural Portland Cement Concrete

Many state highway agencies use various chemicals to deice or anti-ice pavement and bridge surfaces. Most often these are aqueous solutions of various chlorides (e.g., magnesium chloride, sodium chloride, and calcium chloride) or other chemicals such as calcium magnesium acetate, urea, or others. Possible detrimental effects to concrete caused by these chemicals have not been fully examined and documented. Mortar specimens of three different water-to-cement ratios (0.4, 0.5, and 0.6) were immersed in concentrated solutions of various chemical deicers and held above freezing at a constant temperature of 40°F up to 84 days. Considerable expansion and cracking were noted in specimens immersed in the MgCl2 and CaCl2 solutions. Petrographic analysis and quantitative microanalysis were used to positively identify the presence of Mg(OH)2 (brucite) formation in the outer layers of the specimens. Furthermore, the results presented clear evidence of calcium oxychloride formation in the specimens analyzed. Further research is being conducted, including the same immersion test at 40°F on portland cement concrete specimens, to identify whether this distress mechanism is of concern for structures such as roads and bridges when subjected to deicing chemicals containing CaCl2 or MgCl2.

Cleaning of concrete fouled by lichens with the aid of Thiobacilli

Concrete specimens weathered for over a decade in the moderate Belgian climate, showing a black organic outer layer that mainly consisted of lichens, were cleaned with a new biological technique. A mixture of sulphur oxidising bacteria of the genusThiobacillus supplemented with an appropriate nutrient was applied to a fouled concrete surface, either by sprinkling or by submersion. The aim was to remove the fouled layer in such a way that the surface is uniformly cleaned. The general effect of the technique was evaluated by colorimetry and microscopy. Two sets of weathered concrete specimens, containing blast furnace slag cement or ordinary portland cement, were investigated. The effectiveness of the technique depended on the cement type of the concrete specimens. The effect on the ordinary portland cement concrete specimens was in some cases up to a factor 2 stronger than the result on the blast furnace slag cement specimens. The sprinkling treatment was about 50% as effective as the submersion treatment but was very promising in the case of in situ acidification. A side effect was the formation of a gypsum layer on some of the specimens, resulting in a whiter colour.

Evaluation of altered pyroclastics from Rhodope prefecture, Thrace, Greece as constituents of pozzolanic cements

In the Komotini Tertiary basin, tuffs of various types are alternated with tuffites, siltostones, sandstones and marls forming a thick volcanosedimentary sequence. The tuffs are characterised as ash-, fine ash- and in some cases as welded ash tuffs. Crystal-,lappili- and breccia tuffs also occur. The tuffs are built up of glass shards, pumice shards and crystal fragments which are cemented by glassy material. Crystal fragments are represented by quartz crystals. Plagioclase, albite, sanidine and biotite exist as well. Essentially, the vitric parts of the tuffs are altered to zeolites (heulandite 2 and/or mordenite, analcime, laumontite / scolecite), clay minerals (smectite, kaolinite +/or mixed layer I/S of regular type), Si02 minerals (quartz, cristobalite) and K-feldspar. For the purposes of this study, firstly, standard portland cement concrete specimens and concrete specimens with pyroclastic material from three different places, replacing portland cement by 20%, were prepared. The mineralogical composition of the samples under study and the area where they come from, is as follows: a. Iampolis: analcime + quartz + K-feldspar + albite + Illite/Smectite b. Darmeni : analcime + quartz + K-feldspar + albite + calcite c. Skaloma : smectite + cristobalite + heulandite-2 + mordenite + K-feldspar + quartz The compressive strength of the prepared specimens after periods of 7 and 28 days was measured and the pozzolanic activity of the samples was calculated according to ASTM Standard C618. Following the first test, the pozzolanic activity of a second sample from Iampolis area was more extensively studied. The compressive strength of concrete specimens made of 100% Portland cement of 145 type, and concrete specimens that were prepared by replacing Portland cement in proportions of 10, 20, 30 and 40% was determined. From the results of this study it is concluded that the analcimic tuffs could be a potential source for pozzolanic cement. More extensive study is needed for the estimation of the percentage of the altered pyroclastics that gives the optimum results concerning the cement pozzolanic activity. The optimization of the pozzolanic properties of the altered pyroclastics by calcination may be investigated as well.

Microwave Sensing of Moisture Content in Concrete Using Open-Ended Rectangular Waveguide

The existence of moisture in concrete is a major cause of damage to the concrete structure, so there is an increasing need for nondestructive detection and monitoring of moisture content in concrete. Microwave nondestructive testing (MNDT) techniques have advantages over other NDT methods (such as radiography, ultrasonic, and eddy current) regarding low cost, good penetration in nonmetallic materials, good resolution and requirement of only one face of material for testing. In this paper, microwave open-ended rectangular waveguide was used to measure the electromagnetic properties of Portland cement concrete (PCC) over a frequency range of 7.0 to 13.0 GHz. PCC specimens of six different water cement ratio (w/c) were prepared. PCC dielectric properties were evaluated at different moisture content ranges from saturated to oven dry. The results show reflection coefficients, dielectric constants and loss factors increase with increasing moisture content of PCC. At the same values of moisture content, the reflection coefficients, dielectric constants and loss factors of PCC increase with decreasing w/c ratio. The measured values of reflection coefficients, dielectric constants and loss factors can be used to determine the moisture content of PCC.

Characterization of portland cement concrete using electromagnetic waves over the microwave frequencies

A study was conducted to evaluate the effect of the basic properties of Portland cement concrete (PCC) and chloride presence (in PCC) on its dielectric properties over the microwave frequency range of 0.1 to 1 GHz. PCC specimens were prepared at three w/c ratios, 0.35, 0.45, and 0.55, using three aggregate types, limestone, quartzite, and active-silica, and two types of cement, type I and high alkali. Other PCC mixes were prepared and contaminated with two methods, addition of sodium chloride (NaCl) to the mixing water and immersion of hardened PCC specimens (prepared at a 0.45 w/c ratio) in 6% (by wt) NaCl solution after 28 days of curing. The dielectric properties were evaluated using a coaxial transmission line designed to allow measurements over the frequency range of 0.1 to 1 GHz. The dielectric properties of PCC specimens were evaluated over curing time. Powdered PCC samples were obtained from chloride contaminated specimens and chloride contents were determined using Virginia Tech Procedure. The results showed significant effects of curing time on the dielectric properties of PCC specimens and insignificant effects of w/c ratio, air entrainment, and cement type. The dielectric properties showed a significant difference between PCC specimens with different aggregate types. The chloride presence (in PCC) did not influence significantly the PCC dielectric properties.

Microstructural Studies of Alkali-Silica Reaction in Fly Ash Concrete Immersed in Alkaline Solutions

This article presents expansion and microstructural data for a series of concrete mixes containing reactive flint aggregate, with a range of fly ash levels, exposed to various alkaline salt solutions. This study was undertaken to determine whether fly ash has any influence on alkali-aggregate reaction beyond changes in pore solution chemistry; in these tests the external source of alkalis should neutralize pore solution effects. Fly ash was found to be effective in reducing expansion even after extended periods (44 months) of exposure in 1N NaOH at 80°C, notwithstanding the presence of abundant reactive silica and an inexhaustible supply of alkali hydroxides. Higher levels of ash (40%) prevent damaging expansion and cracking in this environment despite considerable evidence of reaction. In some cases, flint grains had been completely removed by dissolution. The addition of Ca(OH)2 at the mixing stage was found to increase the expansion of all the concretes; the effect on concrete with 40% ash was most marked, the expansion increasing by nearly 20 times. The most noticeable difference between deteriorated control specimens (no ash) and concrete with 40% ash was the formation of a calcium-alkali-silica rim on certain flint grains in concrete without ash. Such particles were invariably sites of expansive reaction with cracks emanating from them. The absence of such a feature in concrete with 40% ash is probably linked to the reduction in Ca(OH)2 at the cement-aggregate interface. It is possible that the formation of this reaction rim produces expansive forces itself or acts as a semi-permeable membrane preventing diffusion of alkali silicate solution from the reaction site, thereby leading to osmotic pressure generation. Regardless of the actual mechanism, the presence of Ca(OH)2 appears to be critical for the development of expansion due to alkali-silica reaction. It was observed that the alkalis of the reaction product were distributed in bands. In the Portland cement concrete specimens, the distribution of the gel consisted of a high calcium reaction rim at the aggregate-cement interface with a sodium-rich silica gel adjacent to it, followed by a potassium-rich silica gel. The potassium-rich silica gel appears to have a crystalline, needle-like structure, whereas the sodium-rich silica gel is amorphous. In fly ash concrete specimens in which the formation of calcium-rich reaction rim was prevented, it was observed that the sodium-rich gel had diffused into the surrounding cement matrix, and the potassium-rich gel had remained within the original aggregate boundary.

Design and evaluation of a coaxial transmission line fixture to characterize portland cement concrete

Electrical characterization of portland cement concrete (PCC) is necessary for reliable operation of many electromagnetic nondestructive evaluation (NDE) techniques. Examples of such techniques include ground penetration radar (GPR). For that purpose, PCC specimens were cast, and their complex permittivity and magnetic permeability were measured over a wideband of frequencies (1 MHz to 10 GHz) using both time domain and frequency domain measurement techniques. As part of an ongoing research project, three set-ups to measure the dielectric properties of PCC were designed. The measurements are carried out over a frequency range of 0.1 MHz to 10 GHz. The three different set-ups are parallel plate capacitor (0.1 MHz–40 MHz), coaxial transmission line (0.1 GHz–1 GHz), and TEM horn antenna (0.5 GHz– 10 GHz). This paper discusses the development of the coaxial transmission line fixture. It was designed to allow the evaluation of large PCC specimens and obtain an average effect of PCC components. A time domain reflectometry (TDR) setup was used in the design of the fixture and in testing its performance. A calibration scheme was developed and used to calibrate the fixture. Using a two-port S-parameter model, the complex permittivity and magnetic permeability of the PCC specimens were evaluated by frequency domain measurement. Time domain measurement techniques were based on one-port S-parameter model. Evaluation of the set-up using especially molded PCC specimens showed that curing status can be detected at a lower frequency using the imaginary component of the relative permittivity.

Detection of Chlorides in Concrete Using Low Radio Frequencies

Chloride intrusion into reinforced portland cement concrete (PCC) is of special interest to researchers due to chloride's action as a catalyst and accelerator of PCC reinforcing-steel corrosion. The authors conducted experiments to study the effect of chloride contamination of PCC on its complex permittivity over low radio frequencies (RF) range (0.1-40.1 MHz). Quartzite and limestone were the aggregates used to prepare the PCC mixes at a water-to-cement ratio (w/c) of 0.45. Partial immersion in NaCl solution and the addition of NaCl to the PCC mixing water were the two methods used to induce chlorides into PCC. For the NaCl addition to the mixing water, three levels of chloride contents were used. Dielectric measurements were recorded for PCC specimens during the 28-day curing period and continued for 6 months. Powder PCC samples were gathered occasionally to estimate the chloride content in the PCC specimens. Findings indicate that complex permittivity of PCC specimens increased quantitatively as the chloride content increased, until quantitatively 75 percent of the chloride content estimated theoretical saturation volume. Aggregate type and frequency also significantly impacted on the measured dielectric constant.

New Procedure for Evaluating Bond Strength of Concrete Reinforcement

The bond strength between concrete and reinforcement is critical to the performance of reinforced concrete structures, including continuously reinforced concrete pavements (CRCP). Unfortunately, a widely accepted test is not available for this critical property. Commonly used procedures apply the load to the reinforcing unit and the load is transferred from the unit to the concrete. Poisson's effects are induced in the reinforcement and a reduction in cross section results. The ensuing failure is not generally representative of the stress transfer mode between concrete and reinforcement in most structures. The proposed procedure obviates the Poisson's effects by applying the load directly to the concrete. Load is transferred to the steel in the vicinity of a preformed crack. Applicability of the procedure is demonstrated using a particular type of flat CRCP reinforcement; however, the procedure has been used on conventional steel and glass-fiber reinforced plastic reinforcement with equal success. The loading rate and instrumentation regime are adaptable to the needs of the researcher. Reinforced portland cement concrete specimens of various strengths were tested to evaluate the procedure and the reinforcement itself. The K-value was found to be satisfactory and comparable to conventional steel rebars. Also the mobilization of yield resistance ratios for the flat units were comparable to conventional steel reinforcing units.

New Procedure for Evaluating Bond Strength of Concrete Reinforcement

The bond strength between concrete and reinforcement is critical to the performance of reinforced concrete structures, including continuously reinforced concrete pavements (CRCP). Unfortunately, a widely accepted test is not available for this critical property. Commonly used procedures apply the load to the reinforcing unit and the load is transferred from the unit to the concrete. Poisson's effects are induced in the reinforcement and a reduction in cross section results. The ensuing failure is not generally representative of the stress transfer mode between concrete and reinforcement in most structures. The proposed procedure obviates the Poisson's effects by applying the load directly to the concrete. Load is transferred to the steel in the vicinity of a preformed crack. Applicability of the procedure is demonstrated using a particular type of flat CRCP reinforcement; however, the procedure has been used on conventional steel and glass-fiber reinforced plastic reinforcement with equal success. The loading rate and instrumentation regime are adaptable to the needs of the researcher. Reinforced portland cement concrete specimens of various strengths were tested to evaluate the procedure and the reinforcement itself. The K-value was found to be satisfactory and comparable to conventional steel rebars. Also the mobilization of yield resistance ratios for the flat units were comparable to conventional steel reinforcing units.