Short-term effect of distilled water, seawater and temperature on the crushed and interlaminar shear strength of fiber reinforced plastic composites made by the newly proposed rubber pressure molding technique

2008 ◽  
Vol 29 (6) ◽  
pp. 670-691 ◽  
Author(s):  
Kamal K. Kar ◽  
S.D. Sharma ◽  
A. Mohanty ◽  
P. Kumar
Author(s):  
E Sideridis ◽  
J N Ashton ◽  
R Kitching

The measurement of the interlaminar shear strength of glass-reinforced plastic (GRP) laminates is proposed using an offset four-point bend test on a beam where two (P) of the four forces differ from the other two (Q) and the ratio λ = P/Q depends upon the relative positions along the beam. The paper describes the development of this test which appears simpler, more economic and more realistic in many aspects than other test methods. It is demonstrated theoretically and experimentally that the span length (L), thickness (t) and the ratio λ are important test parameters in determining whether the failure is by shear or by flexure. A test rig was designed and constructed to investigate the influence of these parameters and to determine the interlaminar shear strength of a GRP laminate. Specimens were made from polyester resin containing E-glass fibres in the form of chopped strand mat (CSM). Clear and repeatable interlaminar shear failures have been obtained where L/t was relatively small and Λ large. The crack formation mechanism was studied using photography.


2017 ◽  
Vol 267 ◽  
pp. 103-108 ◽  
Author(s):  
Kakur Naresh ◽  
Shankar Krishnapillai ◽  
Ramachandran Velmurugan

In this study, the Interlaminar shear strength (ILSS) and flexural properties for five different laminate orientations [0°, 45°, [45°/-45°/45°]s, [±45°/0°/90°]s and 90°] of unidirectional carbon fiber reinforced plastic (CRP) and glass fiber reinforced plastic (GRP) composites are investigated. The different approach is used by applying the tensile load on notched specimens for measuring the inter-laminar shear strength. The theoretical flexural properties are obtained using the classical laminate theory [CLT]. The good agreement is obtained between the theoretical model and experimental results. The results indicate that the flexural strength and stiffness are higher for 0° laminate whereas flexural strain is higher for [45°/-45°/45°]s laminates as compared to other laminates. The scanning electron microscopy is used to observe the fracture surface of all laminate orientations of CRP and GRP composites.


Author(s):  
Florian Arendt

A test was done to see if reading a newspaper which consistently overrepresents foreigners as criminals strengthens the automatic association between foreign country and criminal in memory (i.e., implicit cultivation). Further, an investigation was done to find out if reading articles from the same newspaper produces a short-term effect on the same measure and if (1) emotionalization of the newspaper texts, (2) emotional reactions of the reader (indicated by arousal), and (3) attributed text credibility moderate the short-term treatment effect. Eighty-five participants were assigned to one of three experimental conditions. Participants in the control group received short factual crime texts, where the nationality of the offender was not mentioned. Participants in the factual treatment group received the same texts, but the foreign nationality was mentioned. Participants in the emotionalized treatment group received emotionalized articles (i.e., texts which are high in vividness and frequency) covering the same crimes, with the foreign nationality mentioned. Supporting empirical evidence for implicit cultivation and a short-term effect was found. However, only emotionalized articles produced a short-term effect on the strength of the automatic association, indicating that newspaper texts must have a minimum of stimulus intensity to overcome an effect threshold. There were no moderating effects of arousal or credibility pertaining to the impact on the implicit measure. However, credibility moderated the short-term effect on a first-order judgment (i.e., estimated frequency of foreigners of all criminals). This indicates that a newspaper’s effect on the strength of automatic associations is relatively independent from processes of propositional reasoning.


1990 ◽  
Vol 50 (7) ◽  
pp. 801-805 ◽  
Author(s):  
L. E. Matzen ◽  
B. B. Andersen ◽  
B. G. Jensen ◽  
H. J. Gjessing ◽  
S. H. Sindrup ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document