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The National Engineering Education Delivery System (NEEDS) is an entirely new courseware development and distribution system which wiJJ provi de Widespread, rapid, electronic access to an almost arbitrarily large number of diverse instructional modules (2-4). Curricular material in the NEEDS database are organized bya diverse range of indices. Links across dlsdplines are provided in the form of "curricular paths" tlvough the elements in the database. This year, NEEDS will be available not only to this Coalition but to aU engineering sc. hools, both ~~ a library/database and a broad distribution channel for the results of their work in developing new concepts, methods, curricula a. nd tools. NEEDS ADDRESSES KEY ISSUES IN ENGINEERING EDUCATION TODAY Synthesis is developing blueprints for model programs that will systematically restructure our undergraduate curricula to meet the needs and competitive pressures of the twenty-first century.

Response of quasi-isotropic laminates of SiC coated Carbon/Carbon (C/C) composites have been investigated under flexural loading at various temperatures. Varia tion of load-deflection behavior with temperatures are studied. Increase in flexural strength and stiffness are observed with the rise in temperature. Extensive analyses through Optical Microscope (OM) and Non-Destructive Evaluation (NDE) have been per formed to understand the failure mechanisms. Damage zone is found only within the neighborhood of the loading plane. Isoparametric layered shell elements developed on the basis of the first order shear deformation theory have been used to model the thin lami nates of C/C under flexural loading. Large deformation behavior has been considered in the finite element analysis to account for the non-linearities encountered during the actual test. Data generated using finite element analysis are presented to corroborate the ex perimental findings, and a comparison in respect of displacement and stress-stram be havior are given to check the accuracy of the finite element analysis. Reasonable correla tion between the experimental and finite element results have been established.

The present work investigates the damage development under fatigue and static loading in graphite/epoxy laminates. The tensile strength, modulus and tensiontension fatigue data for [0/0/90] 3s laminate were generated at three stress levels (70%, 80% and 90% of ultimate strength). The residual strength and modulus of the specimens were determined at 70% and 90% of the ultimate strength. The characteristic lives of cycles to failure ( N f ) as a function of applied stress were determined using Weibull analysis. The specimens were subjected to cyclic loading a determined percentage of the characteristic life at a given stress level, and the progressive damage determined as a function of applied number of cycles was analyzed using ultrasonic non-destructive technique.The results indicate that there is insignificant degradation in residual strength and stiffness as a result of static tension loading (90% of S ult ). The Weibull analysis shows a significant change in characteristic lives of the number of cycles to failure at stress levels 70, 80 and 90% of ultimate strength. The change of residual strength and modulus is negligible within 50% of N f at both 70% and 90% of S ult . The ultrasonic C-scan in such case shows resin cracks with no delamination and fiber breakage. When the specimens were fatigued for cycles less than half of the total cycles required for failure ( N f ) at 70 % and 90% of the ultimate strength, the change in both residual strength and modulus was observed to be negligible. The ultrasonic C-scans of the fatigue specimens, in these cases, showed micro and macro cracks in the matrix but no delamination and fiber breakage. On the other hand, there was significant reduction in the strength and modulus when the material was fatigued for cycles higher than 50% of N f . The non-destructive evaluation of the fatigued specimens in these cases revealed cracks in the matrix as well as debonding and breakage of fibers and a significant amount of delamination.

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