scholarly journals Performance and Cost-Effectiveness of Short Pitch-Based Carbon Fiber Reinforced Mortar Composite

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4693
Author(s):  
Md. Safiuddin ◽  
George Abdel-Sayed ◽  
Nataliya Hearn

This paper discusses the performance of the short pitch-based carbon fiber reinforced mortar (CFRM) composite considering its key properties and cost-effectiveness. Five different types of mortar composite were produced using 0–4% volume contents of short pitch-based carbon fibers. The mortar composites were tested for inverted slump cone flow (flow time and volume flow), unit weight, air content, compressive strength, flexural strength, impact resistance, and water absorption. The cost-effectiveness of CFRM was assessed based on the performance to cost ratio (PCR), which was calculated for each mortar composite, considering its workability, mechanical properties, and durability. The inverted slump cone volume flow was counted as a measure of workability, whereas the compressive strength, flexural strength, and impact resistance were considered as the major attributes of the mechanical behavior. In addition, the water absorption was used as a measure of durability. The test results revealed that the mortar composite made with 3% carbon fibers provided adequate workability, a relatively high unit weight and low air content, the highest compressive strength, excellent flexural strength, good impact resistance, and the lowest water absorption. It was also found that the PCR increased up to 3% carbon fibers. Beyond a 3% fiber content, the PCR significantly decreased. The overall research findings revealed that the mortar with 3% carbon fibers was the optimum and most cost-effective mortar composite.

Buildings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 300
Author(s):  
Md. Safiuddin ◽  
George Abdel-Sayed ◽  
Nataliya Hearn

This paper presents the water absorption and strength properties of short carbon fiber reinforced mortar (CFRM) composite. Four CFRM composites with 1%, 2%, 3%, and 4% short pitch-based carbon fibers were produced in this study. Normal Portland cement mortar (NCPM) was also prepared for use as the control mortar. The freshly mixed mortar composites were tested for workability, wet density, and entrapped air content. In addition, the hardened mortar composites were examined for compressive strength, splitting tensile strength, flexural strength, and water absorption at the ages of 7 and 28 days. The effects of different carbon fiber contents on the tested properties were observed. Test results showed that the incorporation of carbon fibers decreased the workability and wet density, but increased the entrapped air content in mortar composite. Most interestingly, the compressive strength of CFRM composite increased up to 3% carbon fiber content and then it declined significantly for 4% fiber content, depending on the workability and compaction of the mortar. In contrast, the splitting tensile strength and flexural strength of the CFRM composite increased for all fiber contents due to the greater cracking resistance and improved bond strength of the carbon fibers in the mortar. The presence of short pitch-based carbon fibers significantly strengthened the mortar by bridging the microcracks, resisting the propagation of these minute cracks, and impeding the growth of macrocracks. Furthermore, the water absorption of CFRM composite decreased up to 3% carbon fiber content and then it increased substantially for 4% fiber content, depending on the entrapped air content of the mortar. The overall test results suggest that the mortar with 3% carbon fibers is the optimum CFRM composite based on the tested properties.


2021 ◽  
Author(s):  
Md. Safiuddin ◽  
George Abdel-Sayed ◽  
Nataliya Hearn

Pitch is a viscoelastic polymer material consisting of aromatic hydrocarbons. It is used to produce carbon fibers with sheet-like crystal structures. The aim of the work presented in this paper was to evaluate the effects of pitch-based short carbon fibers on the workability, unit weight, and air content of freshly mixed mortar composite. Experimental investigation was carried out on five different types of mortar composite, including a control mortar. Four mortar composites were prepared including pitch-based short carbon fibers with 1–4% volume contents. The fresh mortar composites were tested to determine their slump, inverted slump cone flow (flow time, mass flow, and volume flow), unit weight, and air content. In addition, the correlation between the slump and flow time of various mortar composites was determined. It was found that the slump decreased with the increasing volume content of carbon fibers. The flow time of mortar composite increased, and therefore its mass flow and volume flow decreased with a greater volume content of carbon fibers. The slump was strongly correlated with the flow time, with a correlation coefficient of 0.9782. Furthermore, the unit weight of the fresh mortar composite decreased due to the incorporation of carbon fibers. However, amongst the different carbon fiber reinforced mortar composites, the mortar with 3% fiber volume content provided the highest unit weight. The air content results were consistent with the unit weight results. The change in air content of various mortar composites followed a trend reciprocal to that of unit weights. When the overall effects of carbon fibers were compared, it was observed that the fiber volume content higher than 3% resulted in a significantly low workability and provided a much lower unit weight with greater entrapped air content.


2021 ◽  
Author(s):  
Md. Safiuddin ◽  
George Abdel-Sayed ◽  
Nataliya Hearn

Pitch is a viscoelastic polymer material consisting of aromatic hydrocarbons. It is used to produce carbon fibers with sheet-like crystal structures. The aim of the work presented in this paper was to evaluate the effects of pitch-based short carbon fibers on the workability, unit weight, and air content of freshly mixed mortar composite. Experimental investigation was carried out on five different types of mortar composite, including a control mortar. Four mortar composites were prepared including pitch-based short carbon fibers with 1–4% volume contents. The fresh mortar composites were tested to determine their slump, inverted slump cone flow (flow time, mass flow, and volume flow), unit weight, and air content. In addition, the correlation between the slump and flow time of various mortar composites was determined. It was found that the slump decreased with the increasing volume content of carbon fibers. The flow time of mortar composite increased, and therefore its mass flow and volume flow decreased with a greater volume content of carbon fibers. The slump was strongly correlated with the flow time, with a correlation coefficient of 0.9782. Furthermore, the unit weight of the fresh mortar composite decreased due to the incorporation of carbon fibers. However, amongst the different carbon fiber reinforced mortar composites, the mortar with 3% fiber volume content provided the highest unit weight. The air content results were consistent with the unit weight results. The change in air content of various mortar composites followed a trend reciprocal to that of unit weights. When the overall effects of carbon fibers were compared, it was observed that the fiber volume content higher than 3% resulted in a significantly low workability and provided a much lower unit weight with greater entrapped air content.


Fibers ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 63 ◽  
Author(s):  
Md. Safiuddin ◽  
George Abdel-Sayed ◽  
Nataliya Hearn

Pitch is a viscoelastic polymer material consisting of aromatic hydrocarbons. It is used to produce carbon fibers with sheet-like crystal structures. The aim of the work presented in this paper was to evaluate the effects of pitch-based short carbon fibers on the workability, unit weight, and air content of freshly mixed mortar composite. Experimental investigation was carried out on five different types of mortar composite, including a control mortar. Four mortar composites were prepared including pitch-based short carbon fibers with 1–4% volume contents. The fresh mortar composites were tested to determine their slump, inverted slump cone flow (flow time, mass flow, and volume flow), unit weight, and air content. In addition, the correlation between the slump and flow time of various mortar composites was determined. It was found that the slump decreased with the increasing volume content of carbon fibers. The flow time of mortar composite increased, and therefore its mass flow and volume flow decreased with a greater volume content of carbon fibers. The slump was strongly correlated with the flow time, with a correlation coefficient of 0.9782. Furthermore, the unit weight of the fresh mortar composite decreased due to the incorporation of carbon fibers. However, amongst the different carbon fiber reinforced mortar composites, the mortar with 3% fiber volume content provided the highest unit weight. The air content results were consistent with the unit weight results. The change in air content of various mortar composites followed a trend reciprocal to that of unit weights. When the overall effects of carbon fibers were compared, it was observed that the fiber volume content higher than 3% resulted in a significantly low workability and provided a much lower unit weight with greater entrapped air content.


Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 683
Author(s):  
Xinfeng Wu ◽  
Yuan Gao ◽  
Tao Jiang ◽  
Ying Wang ◽  
Ke Yang ◽  
...  

Because the aerogel has ultra-low density and good impact resistance, the aerogel material, epoxy-hardener system, and expandable polystyrene beads (EPS) were used to prepare the lightweight aerogel reinforced hollow epoxy macro-spheres (AR-HEMS). The multi-phase epoxy syntactic foam (ESF) was manufactured with the epoxy-hardener system, HGMS (EP-hardener-HGMS), and AR-HEMS by “the compression modeling method.” In this experiment, in order to enhance the strength of the ESF, some different kinds of the carbon fiber (CF) were added into the EP-hardener-HGMS system (CFR-EP). The influence of the volume stacking fraction, inner diameter, and layer of the AR-HEMS and the content and type of the CF in the EP-HGMS (CFR-EP) system on the compressive strength of the ESF were studied. Weighing the two factors of the density and compressive strength, the ESF reinforced by 1.5 wt% CF with 90% AR-HEMS has the better performance. This kind of the ESF has 0.428 g/cm3 nd 20.76 Mpa, which could be applied in 2076 m deep sea.


2012 ◽  
Vol 476-478 ◽  
pp. 1585-1588
Author(s):  
Hong Pan ◽  
Guo Zhong Li

The comprehensively modified effect of cement, VAE emulsion and self-made acrylic varnish on mechanical and water-resistant properties of gypsum sample was investigated and microstructure of gypsum sample was analyzed. Experimental results exhibit that absolutely dry flexural strength, absolutely dry compressive strength, water absorption and softening coefficient of gypsum specimen with admixture of 10% ordinary Portland cement and 6% VAE emulsion and acrylic varnish coated on its surface can respectively reach to 5.11MPa , 10.49 MPa, 8.32% and 0.63, respectively.


2018 ◽  
Vol 225 ◽  
pp. 01022
Author(s):  
Falak O. Abasi ◽  
Raghad U. Aabass

Newer manufacturing techniques were invented and introduced during the last few decades; some of them were increasingly popular due to their enhanced advantages and ease of manufacturing over the conventional processes. Polymer composite material such as glass, carbon and Kevlar fiber reinforced composite are popular in high performance and light weight applications such as aerospace and automobile fields. This research has been done by reinforcing the matrix (epoxy) resin with two kinds of the reinforcement fibers. One weight fractions were used (20%) wt., Epoxy reinforced with chopped carbon fiber and second reinforcement was epoxy reinforced with hybrid reinforcements Kevlar fiber and improved one was the three laminates Kevlar fiber and chopped carbon fibers reinforced epoxy resin. After preparation of composite materials some of the mechanical properties have been studied. Four different fiber loading, i.e., 0 wt. %, 20wt. % CCF, 20wt. % SKF, AND 20wt. %CCF + 20wt. % SKF were taken for evaluating the above said properties. The thermal and mechanical properties, i.e., hardness load, impact strength, flexural strength (bending load), and thermal conductivity are determined to represent the behaviour of composite structures with that of fibers loading. The results show that with the increase in fiber loading the mechanical properties of carbon fiber reinforced epoxy composites increases as compared to short carbon fiber reinforced epoxy composites except in case of hardness, short carbon fiber reinforced composites shows better results. Similarly, flexural strength test, Impact test, and Brinell hardness test the results show the flexural strength, impact strength of the hybrid composites values were increased with existence of Kevlar fibers, while the hardness was decrease. But the reinforcement with carbon fibers increases the hardness and decreases other tests.


Author(s):  
Adriane Pczieczek ◽  
Adilson Schackow ◽  
Carmeane Effting ◽  
Itamar Ribeiro Gomes ◽  
Talita Flores Dias

This study aims to evaluate the application of discarded tire rubber waste and Expanded Polystyrene (EPS) in mortar. For mortars fine aggregate was replaced by 10%, 20% and 30% of rubber and, 7.5% and 15% of EPS. We have verified the consistency, density, amount of air and water retentitivity in fresh state. The compressive strength, water absorption, voids ratio and specific gravity have been also tested in hardened state. The application of rubber powder contributed to the increase in entrained air content and in reducing specific gravity, as well as reducing compressive strength at 28 days. The addition of EPS also contributed to the increase of workability, water absorption and voids ratio, and decreased density and compressive strength when compared to the reference mortar. The use of rubber waste and EPS in mortar made the material more lightweight and workable. The mortars mixtures containing 10% rubber and 7.5% EPS showed better results.


Author(s):  
Nguyen Van Chinh

Drying shrinkage is the main cause of early age cracking of concrete and mortar. A wide range of research has been conducted to reduce the drying shrinkage, including using fibres or chemical admixtures. This paper investigated the effect of shrinkage reducing admixture on the flexural strength, compressive strength, drying shrinkage, water absorption and porosity of mortar. The mix compositions were ordinary Portland cement (OPC) : sand : liquid = 1: 1: 0.38 in which liquid consisted of water and shrinkage reducing admixture (SRA). SRA was used at the proportions of 2%, 4%, and 7% by weight of cement. The test results show that SRA reduces the flexural and compressive strengths of mortar. The reduction in flexural strength and compressive strength at 28 days is 14% and 25%, respectively at 7% SRA dosage. In addition, SRA significantly reduces the drying shrinkage and water absorption of mortar. At 7% SRA dosage, the drying shrinkage at 53 days is reduced by 60% while the water absorption rate at 24 hours is reduced by 54%. However, SRA has a minor effect on the pore size distribution, effective porosity, and cumulative intrusion volume of mortar.


1989 ◽  
Vol 4 (6) ◽  
pp. 1339-1346 ◽  
Author(s):  
C. T. Ho ◽  
D. D. L. Chung

Unidirectional and continuous carbon fiber tin-matrix composites were used for the packaging of the high-temperature superconductor YBa2Cu3O7–δ by diffusion bonding at 170 °C and 500 psi. Tin served as the adhesive and to increase the ductility, the normal-state electrical conductivity, and the thermal conductivity. Carbon fibers served to increase the strength and the modulus, both in tension along the fiber direction and in compression perpendicular to the fiber layers, though they decreased the strength in compression along the fiber direction. Carbon fibers also served to increase the thermal conductivity and the thermal fatigue resistance. At 24 vol. % fibers, the tensile strength was approximately equal to the compressive strength perpendicular to the fiber layers. With further increase of the fiber content, the tensile strength exceeded the compressive strength perpendicular to the fiber layers, reaching 134 MPa at 31 vol. % fibers. For fiber contents less than 30 vol. %, the compressive ductility perpendicular to the fiber layers exceeded that of the plain superconductor. At 30 vol. % fibers, the tensile modulus reached 15 GPa at room temperature and 27 GPa at 77 K. The tensile load was essentially sustained by the carbon fibers and the superconducting behavior was maintained after tension almost to the point of tensile fracture. Neither Tc nor Jc was affected by the composite processing.


Sign in / Sign up

Export Citation Format

Share Document