scholarly journals Study on the Reinforcing Effects of the FRP-PCM Method on Tunnel Linings for Dynamic Strengthening

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Xiaoshan Wang ◽  
Lin Wei ◽  
Zaiquan Wang ◽  
Yujing Jiang ◽  
Liming Zhang ◽  
...  
Keyword(s):  
Stress Reduction ◽  
Axial Stress ◽  
Reduction Rate ◽  
High Strength ◽  
Construction Method ◽  
Fiber Reinforced ◽  
Underground Structures ◽  
Fiber Reinforced Plastic ◽  
Reinforced Plastic ◽  
Reinforcing Effects

In recent years, fiber-reinforced plastic (FRP) has been widely used in the reinforcement of concrete structure fields due to its favorable properties such as high strength, low weight, easy handling and application, and immunity to corrosion, and the reinforcing effects with FRP grids on tunnel linings should be quantitatively evaluated when the tunnels encounter an earthquake. The aim of the present study is to estimate the reinforcing effects of fiber-reinforced plastic (FRP) grids embedded in Polymer Cement Mortar (PCM) shotcrete (FRP-PCM method) on tunnel linings under the dynamic load. A series of numerical simulations were performed to analyze the reinforcing effects of FRP-PCM method quantitatively, taking into account the impacts of tunnel construction method and cavity location. The results showed that the failure region on lining concrete is improved obviously when the type CII ground is encountered, regardless the influences of construction method and cavity location. With the increment of ground class from CII to DII, the axial stress reduction rate R σ increases from 13.18% to 48.60% for tunnels constructed by the NATM, while for those tunnels constructed by the NATM, R σ merely varies from 0.72% to 2.11%. R σ decreases from 43.35% to 34.80% when a cavity exists on the shoulder of lining, while decreasing from 14.7% to 0.12% when a cavity exists on the crown of lining concrete. All those conclusions could provide valuable guidance for the reinforcing of underground structures.

Restraint of Voids Generated Inside Injection Molded Products by In-Mold Pressing Method

2018 ◽  
Vol 12 (6) ◽  
pp. 930-939 ◽  
Author(s):  
Atsushi Motegi ◽  
Tomohiro Hishida ◽  
Yasuhiko Murata ◽  
◽  
Keyword(s):  
Injection Molding ◽  
High Strength ◽  
Compression Molding ◽  
Fiber Reinforced ◽  
Pressing Method ◽  
Glass Fiber Reinforced Plastic ◽  
Fiber Reinforced Plastic ◽  
Reinforced Plastic ◽  
Injection Molded ◽  
Injection Compression Molding

In recent years, long glass fiber reinforced plastic and carbon fiber reinforced plastic have begun to be used for structural components that require high strength. As a result, thick-walled injection molded products are being manufactured. However, defects, known as voids, are generated inside the molded product and decrease the strength of the molded product, posing a significant problem at molding production sites. The partial compression method, which is a type of injection compression molding, is effective in preventing voids in thick-walled injection molding. However, there have been limited studies that comprehensively investigated the effects of the compression conditions on void prevention in thick-walled injection molding products or the shape and dimension of the molded product, or the issues in the molded product produced by applying compression. The authors have previously proposed the in-mold pressing (IMP) method, which allows the application of partial compression without the use of an injection compression molding machine and verified its validity. In this study, we proposed a compression device in which a servomotor-driven hydraulic pump actuator is used to propel a movable rod to apply compression to the melt inside the mold cavity. The IMP method using this device was applied to mold thick-walled products with thicknesses of 10 mm and greater, and the effects of compression on the generation of voids inside the molded product and the shape and dimensions of the product were investigated. The results indicate that the generation of voids can be prevented by application of this method. In addition, it was found that marginal deformations, which can pose issues, occur in the molded product when compressive stresses generated inside the molded product by compression are released after demolding.

Face Milling of Carbon Fiber Reinforced Plastic Using Poly Crystalline Diamond Tool

2014 ◽  
Vol 1017 ◽  
pp. 383-388 ◽  
Author(s):  
Jumpei Kusuyama ◽  
Akinori Yui ◽  
Takayuki Kitajima ◽  
Yosuke Itoh
Keyword(s):  
Carbon Fiber ◽  
High Strength ◽  
Face Milling ◽  
Hole Drilling ◽  
Carbon Fiber Reinforced Plastic ◽  
Fiber Reinforced ◽  
Fiber Reinforced Plastic ◽  
Reinforced Plastic ◽  
Carbon Fiber Reinforced ◽  
Poly Crystalline Diamond

Carbon Fiber Reinforced Plastic (CFRP) is a high-strength and high-elastic-modulus composite material that is hardened by impregning carbon fiber with epoxy resin. Although, many sutdies of hole drilling of CFRP have been conducted, few sutdies of face milling of CFRP have been carried out. Face milling is necessary for surfaceing of aerospace parts, which is indispensable for airplane construction. Machining of CFRP is difficult because of the extreme tool wear and delamination that occur. The authors investigated face milling of CFRP using a newly developed Poly Crystalline Diamond (PCD) tool. The resultts show, that the cutting force and surface roughness are affected by the fiber orientation of the CFRP, and that delamination can easily occur in the outer layer of face-nilled CFRP.

Experimental Research on Interlaminal Shear Strength of GFRP Bridge Decks under Simulated Concrete Environment

2012 ◽  
Vol 525-526 ◽  
pp. 249-252
Author(s):  
Wei Chen Xue ◽  
Kai Fu
Keyword(s):  
Shear Strength ◽  
Bridge Deck ◽  
Bridge Decks ◽  
High Strength ◽  
Sample Surface ◽  
Fiber Reinforced ◽  
Glass Fiber Reinforced Plastic ◽  
Fiber Reinforced Plastic ◽  
Reinforced Plastic ◽  
Shear Strength Degradation

Fiber reinforced plastic (FRP) composite which has high strength, high fatigue resistance, low density, and better corrosion resistances is desirable characteristics for bridge applications, especially decks. According to the ACI 440.3R04, Glass fiber reinforced plastic (GFRP) bridge deck samples were immersed into the simulated concrete environment at 60 for 92d (corresponds to the natural environment 25 years). The results show that, with the time increased, the interlaminal shear strength of GFRP bridge decks decreased significantly. After being exposed to the simulated concrete environment for 3.65d, 18d, 36.5d and 92d, the interlaminal shear strength degradation of GFRP bridge decks were 18.69%, 25.90%, 50.93% and 53.74%, respectively. The micro-formation of the GFRP bridge deck sample surface was surveyed under scanning electron microscopy (SEM), which indicated that with the aging time increased, corrosion pits in the surface of GFRP bridge decks became more obviously and the interface between fiber and resin was severely damaged. Therefore, the degradation of FRP under the simulated concrete environment should be considered in the design of FRP bridge decks.

The Effect of Fiber Winding Angles on the Bending Strength of Fiber-Reinforced Plastic Rods

2007 ◽  
Vol 345-346 ◽  
pp. 661-664
Author(s):  
Hoy Yul Park ◽  
Moon Kyong Na ◽  
Myeong Sang Ahn ◽  
Seog Young Yoon ◽  
Seong Soo Park
Keyword(s):  
Bending Strength ◽  
High Strength ◽  
Shear Stresses ◽  
Fiber Reinforced ◽  
Fiber Reinforced Plastic ◽  
Reinforced Plastics ◽  
Reinforced Plastic ◽  
Bending Load ◽  
The Difference ◽  
Fiber Winding

Fiber-reinforced plastics consist of fibers of high strength and modulus embedded in, or bonded to a matrix with distinct interfaces between them. Because fiber configuration plays a key role in determining mechanical strength of fiber-reinforced plastic rods, especially bending strength of fiber-reinforced plastic rods was measured and simulated numerically in variation with winding angles. Also, stress distribution in fiber-reinforced plastic rods was simulated numerically under the condition of constant bending load to fiber-reinforced plastic rods. The measured bending strength of fiber-reinforced plastic rods in variation with winding angles was different from that of simulated. The difference between measured and simulated results was due to the effect of shear stresses on the strength of fiber-reinforced plastic rods.

scholarly journals Thermal Conductivity of High-Strength Polyethylene Fiber and Applications for Cryogenic Use

2011 ◽  
Vol 2011 ◽  
pp. 1-10 ◽  
Author(s):  
Atsuhiko Yamanaka ◽  
Tomoaki Takao
Keyword(s):  
Thermal Conductivity ◽  
Molecular Weight ◽  
High Molecular Weight ◽  
High Strength ◽  
Fiber Direction ◽  
Fiber Reinforced ◽  
Cross Sectional ◽  
Fiber Reinforced Plastic ◽  
Reinforced Plastic ◽  
Polyethylene Fiber

The local temperature rise of the tape is one of instabilities of the conduction-cooled high temperature superconducting (HTS) coils. To prevent the HTS tape from locally raising a temperature, high thermal conductive fiber reinforced plastic was applied to coil bobbin or spacer for heat drain from HTS tape. The thermal conductivity of ramie fibers increases by increasing orientation of molecular chains with drawing in water, and decreases by chain scission with γ-rays irradiation or by bridge points in molecular chains with vapor-phase-formaldehyde treatments. Thermal conductivity of high strength ultra-high-molecular-weight (UHMW) polyethylene (PE) fiber increases lineally in proportion to tensile modulus and decreases by molecular chain scissions with γ-rays irradiation. This result suggested the contribution of the long extended molecular chains due to high molecular weight on the high thermal conductivity of high strength UHMW PE fiber. Thermal conductivity of high strength UHMW PE fiber reinforced plastics in parallel to fiber direction is proportional to the cross sectional ratio of reinforcement oriented in the conduction direction. Heat drain effect of high strength UHMW PE fiber reinforced plastic from HTS tape is higher than that of glass fiber reinforced plastic (GFRP) and lower than that of aluminum nitride (AlN). In the case of HTS coil, the thermal stability wound on coil bobbin made of high strength UHMW PE fiber reinforced plastic is good as that of AlN, and better than that of GFRP.

Fabrication and Testing of FRP Open Coil Springs

2014 ◽  
Vol 592-594 ◽  
pp. 1065-1069 ◽  
Author(s):  
R. Arularasan ◽  
Y.K. Sabapathy
Keyword(s):  
Automobile Industry ◽  
Weight Ratio ◽  
High Strength ◽  
Fiber Reinforced ◽  
Variable Parameters ◽  
Glass Fiber Reinforced Plastic ◽  
Fiber Reinforced Plastic ◽  
Glass Fiber Reinforced ◽  
Reinforced Plastic ◽  
Low Weight

Increasing competition and innovation in automobile sector tends to modify the existing products or replace old products by new and advanced material products. A suspension system of vehicle is also an area where these innovations are carried out regularly. Now days the automobile Industry has shown much interest in using Fiber Reinforced Plastic (FRP) components replacing conventional steel components due to its “high strength to low weight” ratio. Therefore replacement the steel open coil suspension springs (in heavy automobiles) with Glass Fiber Reinforced Plastic (GFRP) open coil springs with the main aim to reduce its weight and thereby reduce the fuel consumption to some extent. A semi mechanized pultrusion process (E –Glass and Epoxy Resin) and braiding process is selected for fabricating the GFRP open coil springs. It is then tested in lab to study some of the variable parameters. Keywords: Fiber reinforced plastic (FRP) , Coil spring , Pultrusion

Lightweight Camshaft Module Made of High-strength Fiber-reinforced Plastic

MTZ worldwide ◽  
2020 ◽  
Vol 81 (9) ◽  
pp. 26-31
Author(s):  
Katrin Schindele ◽  
Thomas Sorg ◽  
Tilo Hentschel ◽  
Johannes Liebertseder
Keyword(s):  
High Strength ◽  
Fiber Reinforced ◽  
Fiber Reinforced Plastic ◽  
Reinforced Plastic ◽  
High Strength Fiber

scholarly journals Mechanical behavior of patched steel panels at elevated temperatures

2019 ◽  
Vol 1 (1) ◽  
Author(s):  
S Surendran ◽  
G L Manjunath ◽  
S K Lee
Keyword(s):  
Fracture Toughness ◽  
Dynamic Fracture ◽  
High Strength Steel ◽  
High Strength ◽  
Dynamic Fracture Toughness ◽  
Fiber Reinforced ◽  
Fiber Reinforced Plastic ◽  
Reinforced Plastic ◽  
Steel Panels ◽  
The Impact

Preventive maintenance is an accepted practice in engineering to keep the structural reliability of ship hulls at the highest possible level. Designers ensure a longer period in between the consecutive maintenance of ship hull parts to optimize expenditure. This is relevant in view of the difficulty in reaching farthest corners in ballast tanks, fuel storage tanks, cofferdams etc. Prior maintenance of the deck and hull parts save a considerable amount of the owner’s budget.A portable technology like patching becomes more handy and economic. Performance of both unpatched and patched samples during dynamic loading conditions being examined in the present investigation. The high strength steel panels with a dimension of 70mm×15mm×3mm were edge cracked for lengths of 4mm and 7mm, with width of 1mm for both. The edge cracked high strength steel panels are repaired with composite patches using GFRP (glass fiber reinforced plastic), CFRP (carbon fiber reinforced plastic) and AFRP (aramid fiber reinforced plastic). The patching was done by 3 and 5 layered and impact tested by Charpy impact tester at ranges of high temperatures. The amount of energy absorbed in the impact is converted to dynamic fracture toughness values and compared for evaluating the performance of FRP (fiber reinforced plastics). Finite element analysis was done for evaluating the stress intensity factors at different types of patching and testing conditions. Comparatively the AFRP patched samples showed better dynamic fracture toughness values at different temperatures.

scholarly journals Research and Design of Submerged Vehicle’s Propeller Blade

2019 ◽  
Vol 8 (12S) ◽  
pp. 324-329
Keyword(s):  
High Strength ◽  
Fiber Reinforced ◽  
Propeller Blade ◽  
Glass Fiber Reinforced Plastic ◽  
Fiber Reinforced Plastic ◽  
Glass Fiber Reinforced ◽  
Reinforced Plastic ◽  
Ansys Apdl ◽  
Von Mises ◽  
Research And Design

Recently, Fiber Reinforced Composite is used for making a propeller blade to develop its performance by increasing the payload and underwater speed of the vehicle. As a consequence of its feathery weight & high strength, numerous scholars/scientist substituted the conventional metallic material with composite material for crafting the propeller. In the contemporaneous work, predictions of pressure circulation around the profile of a propeller blade as a result of hydrostatic pressure difference are existing. Static structural stress investigation was executed for a single combination i.e. carbon fiber reinforced plastic (CFRP) & for hybrid condensation (a combination of two composite materials) i.e. CFRP & Glass Fiber Reinforced Plastic (GFRP). ANSYS APDL software is used to conclude von Mises pressure developed in the propeller blade. The result has been given away that it is more beneficial to use the hybrid blended material than the composite one. The weight value of propeller blade is found to be lower for the hybrid complexes, proposing the intrinsic worth of the contemporaneous work.

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