Amount Of Polypropylene Fibers Research Articles

Experimental study to compare the strength of concrete with different amounts of polypropylene fibers at high temperatures

It is widely known that adding fibers to concrete improves the properties of concrete, which has a brittle behavior. Although concrete has high compressive strength but poor tensile strength, this has led researchers to offer a variety of ways to deal with this weakness. The use of fibers is one of the methods used to enhance concrete behavior. Fire is one of the most important cases in structures; if the temperature is high or its duration is long, it will cause serious damage to the structure. The present study is an experimental study in which different concrete samples with different amounts of polypropylene fibers and different cement content are exposed once at a normal temperature of 25 °C and again at high temperatures, including 250 °C and 500 °C. The effect of temperature on the compressive and tensile strengths of concrete containing 0.5%, 1.5%, and 2% polypropylene fibres and with cement contents of 200 kg/m3, 260 kg/m3, and 320 kg/m3. The compressive and tensile strength was evaluated at curing 28 days of strength. The results showed a severe strength loss for all concretes after exposure to 500 °C. The relative compressive strengths of concretes containing PP fibers were higher than those of concretes without PP fibers. The tensile strength of concrete was more sensitive to high temperatures than the compressive strength. Based on the test results, it can be concluded that adding 2% PP fibers can significantly promote the residual mechanical properties of concrete during heating. The compressive strength at 25 °C with 2% PP fibres decreases by 43% with cement contents of 200 kg/m3 and 64% with cement contents of 260 kg/m3, and 37% with cement contents of 320 kg/m3, respectively. Also, the compressive strength at 500 °C with 2% PP fibres decreases by 61% with 200 kg/m3, 59% with 260 kg/m3, and 42% with cement contents of 320 kg/m3, respectively.

Experimental study on the properties of ultra-high-strength geopolymer concrete with polypropylene fibers and nano-silica.

Because of the recent progress in materials properties, specifically high-strength concrete, further research is needed to evaluate its suitability, understanding, and performance in the modern-day world. This research aims to enhance the performance of ultra-high-strength geopolymer concrete (UHS-GPC) by adding nano-silica (NS) and polypropylene fibers (PPFs). Three 1%, 2%, and 3% different amounts of PPFs and three NS 5%, 10%, and 15% were utilized in the samples. Various performance parameters of UHS-GPC were evaluated, such as fresh property, compressive strength, modulus of elasticity split tensile, flexural and bonding strength, drying shrinkage, load-displacement test, fracture performance, and elevated temperature. The test outcomes showed that by raising the percentage of PPFs and NS to the allowable limit, the performance of UHS-GPC can be improved significantly. The most improved performance of UHS-GPC was obtained at 2% polypropylene fibers and 10% nano-silica, as the compressive, splitting tensile, flexural. Bond strength was improved by 17.07%, 47.1%, 36.52, and 37.58%, and the modulus of elasticity increased by 31.4% at 56 days. The study showed that the sample with 2% PPFs and 10% NS had excellent performance in the load-displacement test, drying shrinkage, fracture behavior, and elevated temperature. At 750°C elevated temperature, the samples' strength was reduced drastically, but at 250°C, the modified samples showed good resistance to heat by retaining their compressive strength to some degree. The present work showed the suitability of PPFs and NS to develop ultra-high-strength geopolymer concrete, which can be used as a possible alternate material for Portland cement-based concrete.

Performance investigation and parameter optimization of ultra-light aerated concrete using orthogonal experimental design

In order to investigate the influence of different experimental conditions and additives on the performance of ultra-light aerated concrete (ULAC), more than 300 ULAC specimens with a dry density of around 160 kg/m3 were prepared in this study. The optimum conditions of the experimental process and the dosage range of three admixtures were obtained by two series of single-factor experiments. The results show that the unification of experimental conditions is necessary for the experimental process; the range of water-binder ratio (w/b) is 0.5 ∼ 0.52; the replacement ratio range of fly ash and silica fume are (Rf, 3∼6 %; Rsi, 3∼4 %); the amount of polypropylene fiber (Mpp) is 3∼5 %. Through orthogonal experimental design, the dependence of the compressive strength, flexural strength, dry density, thermal conductivity upon Rf, Rsi, w/b, Mpp, and conditioning agent (Ac, an inorganic material) of ULAC is here investigated. The impact of four factors and their interactions on all property indexes (PIs) was studied by analysis of variance. A modified multiple-index assessment method was proposed to optimize the parameter combination for four PIs of ULAC. The results show that the Rf is the significant influencing factor of all PIs, and the interactions among the three active additives significantly impact the performance of ULAC. Nevertheless, the interaction between Rf and w/b has little impact. The repeated tests show that the deviations between the property index and the target value obtained by the theoretical prediction model are 2.63 %, 2.59 %, 2 % and 4.79 %, respectively, and according to the comprehensive weighted scoring method, the deviations between them are 2.56 %, 1.44 %, 4 % and 4.6 %, respectively. The deviations obtained by the two methods are less than 5 %, demonstrating that this method could be widely used in the ULAC multi-index system parameter optimization.

Experimental Study and Failure Criterion Analysis of Rubber Fibre Reinforced Concrete under Biaxial Compression-Compression

In order to examine the biaxial compression-compression properties of rubber fibre reinforced concrete (RFRC), an experimental study on RFRC under different lateral compressive stresses was carried out by considering different rubber replacement rates and polypropylene fibre contents. The failure modes and mechanical property parameters of different RFRC working conditions were obtained from the experiment to explore the effects of rubber replacement rate and polypropylene fibre content on the biaxial compression-compression properties of RFRC. The following conclusions were drawn. Under the influence of lateral compressive stress, the biaxial compression-compression failure mode gradually developed from a columnar pattern to a flaky pattern, suggesting that the incorporation of rubber and polypropylene fibres into the concrete resulted in a significant change in the development of cracks. For different rubber replacement rates and polypropylene fibre contents, the vertical compressive stress exhibited the same developing trend under the influence of lateral compressive stress. Specifically, the lateral compressive stress imposed the minimum effect on the vertical compressive stress when the rubber replacement rate and polypropylene fibre content were 20% and 0.4%, respectively, and imposed the maximum effect when the rubber replacement rate and polypropylene fibre content were 20% and 0%, respectively. With the increase of rubber replacement rate, the vertical peak stress was significantly reduced, which implies that an appropriate amount of polypropylene fibres can increase the vertical peak stress to a certain extent. Then, the biaxial compression-compression mechanism of RFRC was analysed from the microscopic level by using scanning electron microscope (SEM). Meanwhile, based on Kupfer’s biaxial compression-compression failure criterion and the octahedral stress space, a biaxial compression-compression failure criterion for RFRC was proposed, which was proven to have good applicability. The research results of this study provide important theoretical basis for the engineering application and development of RFRC.

Preparation and application of the novel resin microcapsules in self-repairing cement composites with polypropylene fibers

According to this article, the novel, highly absorbent, resin microcapsules prepared by the sharp hole-bath method, together with the polypropylene fibers, were used in the cementitious materials, with an aim to study the impacts of the dosage of polypropylene fibers, the mass fraction of microcapsules and the curing age on the strength of mortar and its self-repair effect. The uniaxial compression test and the permeability test were also applied to evaluate the mechanical properties of specimens and the self-repair effect of cracks. The results showed that when the amount of microcapsules is 1.5% and the amount of polypropylene fibers is 0.17%, the specimen reaches its peak strength, meanwhile the microcapsules have no negative effect on its initial compressive strength. When the amount of microcapsules is 0.75% and the amount of polypropylene fibers is 0.17%, the strength repair rate and the seepage repair rate of cement-based materials reach the best. In addition, the strength repair rates showed that, compared with the single addition of microcapsules, the ‘bridging effect’ of polypropylene fibers could help microcapsules better complete the crack self-repair work.

Modeling and analysis of fiber-reinforced high-performance concrete strength prediction based on nonlinear programming

In this study, the nonlinear programming software Design-Expert and Lingo were used to establish a mathematical model between the fiber volume fraction and the strength of high-performance concrete for steel and polypropylene fibers in single or mixed concrete. The interaction of the two kinds of fiber in the matrix was considered. The results show that the fiber-reinforced high-performance concrete strength model conformed to the quadratic and cubic functional relation. The significance analysis of the model regression variance was performed, showing that the amount of polypropylene fiber had no significant effect on splitting strength and flexural strength of concrete while, steel fiber and hybrid fiber affected the compressive strength significantly. Additionally, polypropylene fiber helped increase the compressive strength of concret; and steel fiber had a greater effect on improving splitting tensile and flexural strength. The correlation between the predicted and tested strength of both models was demonstrated by SPSS statistical analysis, with greater significance when compensating for the discrete points of the predicted strength. A comparative analysis of existing strength prediction models verified the model's applicability for fiber-reinforced fiber-performance concrete. By modifying the discrete points, the correlation between the experimental values of compressive, splitting and flexural strength of concrete and the predicted values of the Pearson coefficient increase by 14.19%, 32.78% and 9.58%, respectively. The ratio value of predicted strength to tested strength is close to 1, while a large error appeared when the existing models were used for fiber-reinforced high performance concrete.

Comparison of the Mechanical Behavior of Concrete Containing Recycled CFRP Fibers and Polypropylene Fibers

The incorporation of natural or recycled fibers in concrete represents a field for improvement in this structural material and a step towards sustainability. The objective of this research is to determine whether the addition of recycled carbon fibers (CFRP), which have been hardened using epoxy resin, improves the behavior of concrete and whether its performance is comparable to that achieved by adding polypropylene fibers, which would result in a viable recycling alternative for this type of fiber. In order to explore this objective, 120 specimens were produced, on which compression, flexural, and impact tests were performed, and into which recycled CFRP fibers or polypropylene fibers were incorporated. By comparing the results obtained, it may be concluded that the addition of fibers substantially improves the ductility of the concrete and reduces the spalling effect when compared to concretes without added fibers. The concretes containing recycled CFRP fibers in quantities of 3 kg/m3 and 6 kg/m3 obtain better flexural and impact behaviors than concretes featuring the same amounts of polypropylene fibers, making this recycling alternative viable for CFRP fibers as well as reducing the amount of energy and raw materials that would be used to manufacture the fibers.

Experimental statistical models for the study of cement-concrete for road pavements

The article presents the calculation and statistical analysis of the experimental statistical (ES) model of the several samples of concrete and reinforced concrete for road pavements. For the analysis, the Program (dialogue) Complex COMPEX was used, which was developed at the Odessa State Academy of Civil Engineering and Architecture by scientists of the scientific school of prof. V.A. Voznesensky. In the research of the structure and properties of rigid road pavements concrete with an optimal plan, a 4-factor experiment was carried out, in which the following factors of concrete composition were varied: X1- the amount of Portland cement PC II / A-Sh-500, from 400 to 500 kg / m3; X2- the amount of polypropylene fiber from 0 to 2 kg / m3; X3- the amount of Metakaolin, from 0 to 30 kg / m3; X4- the amount of complex action additive (polycarboxylate type) Coral ExpertSuid-5, from 0.6 to 1% of the cement mass. An increase in the amount of Coral ExpertSuid-5 additive from 0.6 to 0.8% of the cement mass is noticeable, by 10…12%, and decreases the W/C ratio of mixture. An increase in the amount of this additive of complex action to 1% causes a further, but less noticeable, decrease in W/C ratio.

The effect of polypropylene fiber addition to mechanical properties of concrete

Concrete is the one of the building construction materials that has a high compressive strength, but it has lower tensile strength. The addition of fibers to concrete is expected to improve its mechanical properties. In this study, the concrete was added with Polypropylene (PP) fiber with a length of 12 mm. The compressive strength of concrete specimens was 20 MPa with the variety of fiber used was 0.5 kg/m3; 1 kg/m3; and 1.5 kg/m3. The test were conducted on 36 specimens in the form of cylinders and cubes. The tests were compressive strength, split tensile strength and water absorption at the age of 28 days. The highest value of the compressive strength of the fiber concrete was the amount of Polypropylene fiber 1 kg/m3, namely 2.92 MPa, increase of 6.92% of the compressive strength of concrete without additional fiber. The highest value for the split tensile strength in the amount of Polypropylene fiber 1 kg/m3 was 2.34 MPa or an increase of 21% from the tensile strength value of concrete without additional fiber. Meanwhile, the lowest water absorption capacity of concrete is the addition of 1.5 kg/m3 of fiber, which is 2.366% or has decreased by 64% from the concrete without fiber.

Effect of polypropylene fiber content on compressive and flexural performance of recycled concrete

Recycled concrete was a kind of green, environmental protection and energy-saving building material, and its mechanical properties can be improved by adding polypropylene fiber. Taking the polypropylene fiber content as a parameter, experiment of cube compressive strength and bending strength on polypropylene fiber recycled aggregate concrete (PFRAC) and natural aggregate concrete were done, among which the PFRAC has 50% replacement rate of recycled aggregate. Through the comparison of strength and fracture mode of specimens, the influence of polypropylene fiber content on the pressure resistance and fracture resistance of recycled concrete were studied, and the recycled concrete’s appropriate amount of polypropylene fiber which strength can reach to natural aggregate concrete were obtained. The results were as follows: the compressive strength and bending strength of recycled concrete with polypropylene fiber were obviously intensified and the strength continuously intensifies along with the adding of fiber content. The compressive strength and bending strength of PFARC exceed that of natural aggregate concrete when fiber content was up to 1.0kg/m3. The recycled concrete with polypropylene fiber can still maintain the property of crack without breaking after damage, and the britttle fracture morphology wouldn’t occur in it.

Piezoresistivity enhancement of functional carbon black filled cement-based sensor using polypropylene fibre

In this study, different dosages of carbon black (CB) and polypropylene (PP) were added to develop functional cementitious composites as cement-based sensors. The results show that electrical conductivity increased with the amount of PP fibres, due to the enclosed CB nanoparticles and more conductive passages. The compressive strength slightly decreased, while the flexural strength was significantly increased with the increased amount of PP fibres. The improvement is mainly achieved by the reduced CB concentration in cement matrix and the excellent tensile strength of PP fibres. Under the cyclic compression, the piezoresistivity increased by three times for 0.4 wt% PP fibres filled CB/cementitious composite, regardless of the loading rates. The flexural stress sensing efficiency was considerably lower than that of compressive stress sensing, but it increased with the amount of PP fibres. Moreover, fitting formulas were proposed and used to evaluate the self-sensing capacity, with the attempts to apply cement-based sensors for structural health monitoring.

Effect of Polypropylene Fiber on Frost Resistance of Cemented Soil

Polypropylene fiber is widely used as a reinforcing material in composite materials of various engineering projects, because it has high strength and corrosion resistance. In this study, with the purpose of examine the impact of discrete polypropylene fiber on frost resistance of cemented soil, cemented soil treated with polypropylene fiber is used as the research sample. Firstly, the impact of curing time, fiber content and length on the strength of cemented soil has been considered. And then, the frost resistance characteristics of cemented soil reinforced by polypropylene fiber with the content of 0.5% have been investigated. The results show that with the development of curing time, the strength of cemented soil increases logarithmically. By adding an appropriate amount of polypropylene fiber, the strength of the specimen may be improved. In this study, cemented soil reinforced by polypropylene fiber 0.1% in content and 3 mm in length has the best reinforcement effect. After 21 cycles of freezing and thawing processes, a sharp decline in strength of cemented soil without fiber, and the strength loss ratio is up to 45%. There are cracks in the specimens, and some of the specimens have broken off. Differently, after 21 freeze-thaw cycles, the strength of the cemented soil with fiber decreased less, and the strength loss ratios are between 1 and 13%, and there are only small cracks on the surface of specimens. The results show that adding discrete polypropylene fiber is a suitable method to prevent the generation and development of internal cracks in the cemented soil during freezing and thawing, thereby improving the frost resistance. These results can be used as a reference for the application of cemented soil reinforced with fiber in seasonal frozen regions.

Effects of Polypropylene Fiber Content on Strength and Workability Properties of Concrete

Low tensile strength of plain concrete is due to the inherent presence of microcracks due to drying shrinkage occurrences or other causes of volume changes in concrete. The addition of a proper amount of fibers to concrete would act as crack arrester thus improves its static or dynamic properties. In this paper, the concrete with different amount of polypropylene fiber was investigating to find out the fibers effect on its fresh and mature properties. A plain concrete mix (reference mix) prepared for comparison purposes. Nine concrete mixes were prepared with different fiber volume fraction (FVF) ranging from 0.06% to 2.16%. It has been found out that the fiber content of the concrete mix will increase compressive, splitting, and flexural strengths of the concrete at the age of 28 days. The strengths increased and reached their maximum value at a corresponding (FVF) of about 0.36%. In comparison with the reference mix, the increase in the maximum compressive strength was about 18%, while the increase in maximum splitting tensile strength was about 16% and the increase in flexural strength was about 14%. When the fiber content increased beyond the mentioned 0.36% volume fraction: The concrete strengths started to decrease due to high volume fiber interface with the cohesiveness of the concrete matrix causing difficulty in concrete compaction with lowering its workability. At fiber (FVF) of 0.96%, the concrete slump value became zero. Thus, forced vibration needed for the compaction. For each mature concrete mix density and water absorption percentage were measured. It has been noticed that with an increase of fiber dosage in the concrete mix its density will decrease leading to contrarily an increase in the water absorption percentage. This was due to an increase in air void in the concrete due to the reduction in the workability of the concrete.

Lightweight foamed concrete with foam agent addition

Lightweight foamed concrete with foam agent addition varied from 0 to 7wt% was fabricated and the influence of foam stabilizer and polypropylene fiber (PPF) addition on mechanical performance of lightweight foamed concrete was researched. The experimental data revealed that the density, thermal conductivity, flexural and compressive strength exhibited a rapidly downward trend with the increase of foam agent content due to generation of a large number of pores by decomposition of foam agent. The samples with foam stabilizer addition possessed better mechanical properties and lower thermal conductivity compared to the samples without foam stabilizer addition due to the improvement of pore structure. Besides, an appropriate amount of PPF could enhance flexural and compressive strength of specimens, while excess PPF was proven to be counterproductive.

Evaluation of Ʋ-Lnp' Curves for the Stabilization of Saline Clayey Soils

Saline soils are one of the challengeable soils that can cause many problems in civil engineering designs. In this study, volume change behavior and stress path changes in the Ʋ-Lnp' space of these soils, and the effect of stabilization and reinforcement on them have been investigated. Case study of this research is Amirkabir Highway between Qom and Kashan. In 54th Km of this highway, road surface is distorted and it is observed that its soil is saline clay in field investigation; and considering surface flow of water in that place, it is induced that, probably, the presence of water causes such a condition. For this purpose, after sampling and conducting preliminary experiments such as particle size analysis, Atterberg limits and compaction, first of all, the soil of considered place was examined by swelling potential and consolidation tests. as a result, volume change behavior parameters of undisturbed and disturbed soils have been determined and it was specified that disturbed soil has a considerable swelling potential. Then swelling potential and consolidation tests have been conducted on stabilized samples with different amount and curing time of lime, epoxy – resin polymer and also reinforced samples with different amount of polypropylene fiber; moreover, their results for two cases of stabilized and non-stabilized samples have been compared. According to the results of the consolidation experiments and the potential for swelling, it is observed that the impaction strongly affects the volume behavior and the soil stress path. The comparison among swelling parameters (free swelling and swelling pressure) of stabilized samples with polymer and lime and reinforced samples with polypropylene fiber showed that all of these materials reduce free swelling, but for the case of swelling pressure, with 9 % of polymer swelling pressure increases and for other cases this pressure decreases, that this issue is one of disadvantages of polymer stabilization. The results obtained from the consolidation test indicate that the slope of the normal consolidation line λ and the swell line slope κ in the stabilized samples are smaller than the unstabilized samples.

PARAMETERS AFFECTING THE STRUCTURAL ANALYSIS OF A TUNNEL STRUCTURE EXPOSED TO FIRE

Behaviour of cut-and-cover tunnels exposed to fire should be analysed by using a realistic structural model that takes account of mechanical and thermal effects on the structure. This has been performed with the aid of Finite Element (FE) software package called SOFiSTiK in parallel, for two types of elements as a scope of research project financed by the German Bundesanstalt für Straßenwesen BAST. Since the stiffness of the structure at elevated temperatures is highly affected, a realistic model of structural behaviour of the tunnel could be only achieved by considering the nonlinear analysis of the structure. This has been performed for a 2–cell cut and cover tunnel by taking account of simultaneous reduction of stiffness and strength and the time-dependent increasing indirect effects due to axial constraints and temperature gradients induced by elevated temperatures. The thermal analyses have been performed and the effects were implemented into the structural model by the multi-layered strain model. The stress–strain model proposed by EN 1992-1-2 is implemented for the elevated temperature. Since there was sufficient amount of Polypropylene fibres in the concrete mixtures, modelling of spalling was excluded from the analysis. The critical corresponding stresses and material behaviour are compared and interpreted at different time stages. The main parameters affecting the accuracy and convergence of the results of structural analysis for the used model are identified: defining a realistic fire action, using concrete material model fulfilling the requirements of fire situation in tunnels, defining appropriate time intervals for load implementations. These parameters along with other parameters, which influence the results to a lesser degree, are identified and investigated in this paper.

EXPERIMENTAL AND NUMERICAL ANALYSIS OF ULTRA HIGH PERFORMANCE CONCRETE (UHPC) MEMBERS IN CASE OF FIRE

<p>The research activity in progress and the advancements in concrete technology are leading to an increased use of high performance and ultra high performance concrete in structural engineering. Due to its high compressive strength and ductile behavior in combination with steel fibres, UHPC structural members can be designed as slender and light structures compared to standard concrete design. This increasingly leads to the option in architectural design to highlight the bearing capacity of the building without hiding the structural components.</p><p>In case of fire safety design a disadvantageous behavior of UHPC compared to normal strength concrete is well known and documented. The high packing density of the cement matrix is the main reason for explosive spalling behavior when exposed to fire. To avoid spalling, an appropriate amount of polypropylene fibres has to be introduced in the concrete mix design. In addition, slender and light structures are in general more sensitive to fire exposure due to the higher surface to volume ratio.</p><p>In this paper, the analysis of the thermal and mechanical material properties using experimental and numerical methods is presented. The investigations were carried out during the priority program 1182 in the research project “Theoretical and experimental determination of the high temperature behavior of ultra high performance concrete (UHPC)”, funded by the German Research Foundation (DFG), see (Schmidt 2014) and (Hosser et al. 2014).</p>In the project the thermal properties heat conductivity, specific heat capacity and the temperature dependent density as well as the mechanical properties like the temperature dependent stress-strain-relation and thermal expansion were experimentally determined. In addition, the optimum fibre content was determined. The findings of the project were used to develop a material model and checked against experimental results on fire exposed UHPC columns using a FE model.

The Reasonable Amount of Polypropylene Fiber on Low-Intensity Manufactured Sand Concrete in the Case of Fixed Powder Paste

Compared with the river sand, manufactured sand’s particle type and gradation is relatively poor and the surface is mat .The manufactured sand also has a big effect on the workability of concrete. In this paper,the Equivalent powder paste’s volume of manufactured sand concrete was determined according to Mehta and Aitcin’s ideas for the preparation of HPC,at the same time,the equivalent powder paste volume is assumed as the cement paste volume in the experiment. The influence of polypropylene fiber on Manufactured sand concrete’s workability and Compressive strength were researched in the case of fixed powder paste .

Coalescence filtration performance of blended microglass and electrospun polypropylene fiber filter media

Submicron polypropylene (PP) fibers of three different sizes (300nm, 600nm, and 900nm) were prepared via electrospinning. The fibers were blended with microglass (MG) fibers to form composite media in varying fiber concentrations to obtain PP to MG fiber surface area ratios (AR) of 0.5, 1 and 2. The effects of fiber size and amount of electrospun PP fibers on wettability and filtration performance of the blended PP+MG media were measured. The wettability of the filter media were characterized by a modified Washburn test and expressed as the lipophilic to hydrophilic (L/H) ratio. The wettability characterization shows that hydrophobicity of filter media increases with the amount and size of electrospun PP fibers. In liquid–liquid coalescence experiments the amount and fiber diameter of the electrospun PP fibers significantly affected the separation efficiency and the pressure drop as compare to MG fiber only media. The separation efficiency was greatest for the smallest fibers (300nm) and the intermediate AR of 1.0. The pressure drop tended to increase with the amount of PP fiber and with fiber diameter.

폴리프로필렌 섬유로 보강된 하이볼륨 플라이애시 시멘트 복합재료의 성능 향상 기법

폴리비닐알코올 섬유와 폴리에틸렌 섬유 등의 합성 섬유는 고연성 섬유보강 시멘트 복합재료를 제조하는데 성공적으로 사용되고 있다. 폴리프로필렌 섬유 역시 복합재료를 제조하는데 사용되고 있지만, 고연성을 구현하는 목적보다는 고온에 노출된 콘크리트의 내화 성능 향상 목적으로 사용되고 있다. 이 연구에서는 폴리프로필렌 섬유로 보강된 시멘트 복합재료의 성능을 향상시키는 방법에 대하여 논하고자 한다. 폴리프로필렌 섬유보강 시멘트 복합재료의 성능을 평가하기 위하여 5가지 배합을 결정하였다. 1종 보통포틀랜드시멘트 (OPC)와 OPC를 다량 치환한 플라이애시를 결합재로 사용하였고 물-결합재 비는 0.23~0.25이다. 또한 부피비로 2%의 폴리프로필렌 섬유가 사용되었으며, 연성을 향상시킬 목적으로 폴리스틸렌 비드가 사용되었다. 슬럼프, 밀도, 압축강도, 1축 인장 실험을 포함한 일련의 실험을 수행하였으며, 실험결과, 파괴역학, 마이크로역학, 통계이론을 이용하여 폴리프로필렌 섬유보강 시멘트 복합재료의 성능을 향상할 수 있는 것으로 나타났다. The synthetic fibers including Polyvinyl alcohol and Polyethylene fibers have been successfully used in the manufacture of high ductile fiber reinforced cementitious composites. Polypropylene (PP) fiber has also been used in composites, not for the purpose of achieving a high level of tensile ductility but to improve the fire resistance performance of concrete exposed to high temperatures. This paper discusses the method for enhancing the performance of composites supplemented with PP fiber. Five types of mixture proportions were designed with high volume fly ash for testing the performance of composites. Type I cement and fly ash F were used as binding materials. The water-to-binder ratio was 0.23~0.25, and the amount of PP fiber used was 2 vol%. Polystyrene bead were also used to increase the tensile ductility of composites. A series of experiments including slump, density, compression and uniaxial tension tests were performed to evaluate the performance of cementitious composites supplemented with PP fiber. From the test results, it was exhibited that the performance of composites supplemented with PP fiber can be enhanced by adopting the mechanics and statistics theory.