The National Science Foundation has supported creation of eight engineering education coalitions: ECSEL, Synthesis, Gateway, SUCCEED, Foundation, Greenfield, Academy, and SCCME. One common area of work across the coalitions has been restructuring first‐year engineering curricula. Within some of the coalitions, schools have designed and implemented integrated first‐year curricula. The purpose of this paper is fourfold: 1) to review the different pilot projects that have been developed; 2) to abstract some design alternatives that can be explored by schools interested in developing an integrated first‐year curriculum; 3) to indicate some logistical challenges; and 4) to present brief descriptions of various curricula along with highlights of the assessment results that have been obtained.

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The mode II delamination fracture toughness of a ductile and a brittle unidirectional graphite/epoxy composite has been studied using the end-notched flexure (ENF) test and the end-loaded split laminate (ELS) test. The stress field in the vicinity of the crack tip of a split laminate beam under mode I and mode II (ELS test) conditions has been determined by means of a finite-element analysis. Also, the micromechanics of mode II fracture have been studied during in situ and postmortem observations of the fracture process. Both the ENF and ELS tests give similar values for GIIc. However, because elastic material behavior is assumed in the analysis, the GIIc results for a ductile composite are somewhat uncertain because permanent deformation is observed. The ELS test provides a pure shear stress state in the vicinity of the crack tip. The formation of hackles in composites made with brittle resins provides a more tortuous path for the crack leading to an increased resistance to delamination under mode II conditions compared to mode I. However, extensive resin deformation and yielding play a more significant role in the fracture resistance for mode II loading of composites made using a rubber-toughened epoxy.

A new modified beam theory analysis is presented for the ENF specimen, which is used to evaluate the mode II delamination fracture toughness of fiber reinforced composite materials. The analysis combines the solution of a beam on a generalized elastic foundation to incorporate the effect of crack tip deformation, and a Timoshenko Beam Theory solution of the ENF to incorporate transverse shear on the predicted energy release rates. A distinctive feature of this approach is that crack tip deformation and shear deformations are treated separately and explicitly in accounting for deviations from simple beam theory. Two unknown parameters are introduced, however, that must be determined by comparison with finite element solutions. The resulting solution nevertheless demonstrates considerable accuracy over a wide range of material properties (e.g., axial to shear modulus ratios) and crack lengths. In addition, the current analysis compares very favorably with other analyses of the ENF that incorporate the effect of crack tip deformations on the energy release rate.