Prediction of Interface Shear Stresses in Elastoplastic Moment-Varying Zones of Advanced Composite Material-Strengthened Concrete Members

The need to reduce the overall weight of aeronautical and space structures while preserving or even improving their performances make the research and development in the field of advanced composite materials necessary for the advancement of aerospace technologies. This paper provides an overview of composite materials and their fiber reinforcement technology in aerospace field. We discuss the reasons for aircraft manufacturers and airlines to use composites and illustrate the definition of composite material. Then, we list the advantages and disadvantage of composite materials and cite different fiber reinforcement technologies of carbon fibers, aramid fiber, UHMWPE, etc. At last, we summarize the present and future applications of composites materials in aerospace and other civil fields. A conclusion is drawn that in the future, composite materials are set for their development, while continually decreasing its costs is still an important task.

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Influence of Ageing on Flexible Pavement Interface Bond under Repeated Shear Stresses

Britain International of Exact Sciences (BIoEx) Journal ◽

10.33258/bioex.v2i2.219 ◽

2020 ◽

Vol 2 (2) ◽

pp. 462-475

Author(s):

Saad Issa Sarsam ◽

Samah Abdulrazzaq AL Nuaimi

Keyword(s):

Shear Strength ◽

Permanent Deformation ◽

Research Work ◽

Application Rate ◽

Shear Stresses ◽

Interface Shear ◽

Concrete Core ◽

Application Rates ◽

Tack Coat ◽

Interface Bond

The durability of interface bond was not sufficiently taken into consideration, and the research work in this field is scares and scattered. The interface bond usually practices dynamic shear stresses throughout its service life while ageing due to volatilization provide stiffness at the interface. In this investigation, an attempt has been made to assess the durability of the interface bond in terms of resistance to ageing under repeated shear stresses. Two types of tack coat (Rapid Curing cutback RC-70 and Cationic Medium setting emulsion CMS) and three application rates have been implemented in the preparation of two layers slab samples (base overlaid by binder, and binder overlaid by wearing) courses using roller compactor. Asphalt concrete core specimens were obtained from the roller compacted slab samples and subjected to long term ageing, then the specimens were subjected to 1200 repeated shear stress cycles. The accumulation of permanent deformation was monitored. Afterwards, the specimens were tested for interface shear strength at 20 °C. Control specimens were also tested for comparison. It was concluded that ageing reduces the total microstrain for RC-70 tack coat by (43.6, 25.6, and 29.5) % and (50, 51.3, and 30.2) % for (binder-base) and (wearing-binder) interfaces for the application rate of (0.15, 0.33, 0.5) l/m2 respectively. However, ageing reduces the total microstrain for CMS tack coat by (37, 35.5, and 40.3) % and (45.2 , 49, and 46.8) % for (binder-base) and (wearing-binder) interfaces for the application rate of (0.1, 0.23, 0.35) l/m2 respectively. Ageing increases the interface bond shear strength by a range of (8-27)% for various interfaces, tack coat type and application rates.

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Advanced Composite Material Applications to F-14A Structure

Fifth Conference on Composite Materials: Testing and Design ◽

10.1520/stp36900s ◽

2009 ◽

pp. 30-30-10

Author(s):

H Forsch

Keyword(s):

Composite Material ◽

Advanced Composite

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Experimental analysis of interfacial shear stress and electrical resistance of indium tin oxide-coated polyethylene terephthalate films for a whole folding test

Journal of Plastic Film & Sheeting ◽

10.1177/8756087919894272 ◽

2019 ◽

Vol 36 (2) ◽

pp. 130-150 ◽

Cited By ~ 1

Author(s):

Bor-Jiunn Wen ◽

Shih-An Huang ◽

Ting-Yu Tseng

Keyword(s):

Shear Stress ◽

Polyethylene Terephthalate ◽

Tin Oxide ◽

Indium Tin Oxide ◽

Electrical Resistance ◽

Interfacial Shear Stress ◽

Interfacial Shear ◽

Shear Stresses ◽

Interface Shear ◽

Conductive Substrate

The purpose of this study is to analyze the performance of the flexible conductive substrate by interfacial shear stress. This study performed automatic liquid-crystal modulating common-path interferometry (LMCI) optical inspections on 125-µm polyethylene terephthalate (PET) substrates having indium tin oxide (ITO) coating thicknesses of 80 nm, 160 nm, and 230 nm. The nonlinear characteristic of the stress-optical coefficient of the ITO material is obtained using LMCI. To validate the performance of the flexible conductive substrate, this study has utilized an automatic sliding-folding testing platform (ASTP) for a whole-folding test. Eventually, this study successfully has utilized interface shear stresses to validate the performance of the flexible conductive substrate depended on the different thicknesses of the conductive layers for whole-folding test by using LMCI and ASTP. According to the measurement results, as the folding radii decrease and the ITO thicknesses of ITO-coated PET substrates increase, the changes of interfacial shear stresses increase in compressive direction and the change-rates of electrical resistance of ITO-coated PET substrate also increase. Therefore, the interfacial shear stress measurement and analysis results depicted on flexible conductive substrates provide a validation for improving the manufacturing process and for reducing process residual stresses.

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Research on EIS-Based Anomaly Detection Technique for Composite Materials

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.3056 ◽

2014 ◽

Vol 556-562 ◽

pp. 3056-3059

Author(s):

Chao Sun ◽

En Sheng Dong ◽

Yong Heng Li ◽

Bing Zhu

Keyword(s):

Composite Material ◽

Composite Materials ◽

Anomaly Detection ◽

Fiber Composite ◽

Electrical Impedance Spectroscopy ◽

Carbon Fiber Composite ◽

Advanced Composite ◽

Advanced Composite Materials ◽

Unit Model ◽

Double Electrode

The application of advanced composite materials in airplane is becoming more and more. Along with the increase of its service time, it may be abnormal. It needs to take an anomaly detection. The electrical impedance spectroscopy (EIS) is applied to the anomaly detection of composite material components in airplane. A uniplanar sensor with double-electrode and two carbon fiber composite samples are made, an experiment circuit is designed. In order to verify the effectiveness of the experimental circuit, the EIS of the Randles unit model circuit is measured, as well as the two composite material samples using the dual-electrode measurement method. The picture of EIS is drawn in Matlab and comparison and analysis are carried out. The preliminary experimental results indicate that the anomalies can be seen by measuring the EIS of the composite materials. It is feasible for the EIS to be applied in the anomaly detection of the composite materials in airplane.

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