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A corrective Smoothed-Particle Method (CSPM) is proposed to address the tensile instability and, boundary de®ciency problems that have hampered full exploitation of standard smoothed particle hydrodynamics (SPH). The results from applying this algorithm to the 1-D bar and 2-D plane stress problems are promising. In addition to the advantage of being a gridless Lagrangian approach, improving the above two major obstacles in standard SPH makes it attractive for applications in computational mechanics.

Two different solution algorithms of the corrective smoothed particle method (CSPM) are developed and examined with linear elastodynamic problems. One is to use the corrective ®rst derivative approximations to solve the stress-based momentum equations, with stresses evaluated from the strains. This is an approach that has widely been adopted in smoothed particle hydrodynamics (SPH) methods. The other is new, in which the corrective second derivative approximations are used to directly solve the displacement-based Navier equations. The former satis®es the nodal completeness condition but lacks integrability; on the contrary, the latter is truly complete. Numerical tests show that the latter outperforms the former as well as other existing SPH methods, as expected.

A method for predicting impact-induced delamination in composite lami nates was proposed. This method is suitable for low velocity impact with heavy impactors. Static delamination fracture toughness was used to predict delamination crack growth under impact conditions. Curing stresses were also considered and found to play a signifi cant role in evaluating the fracture toughness of some laminates such as [905/05/90 5]. Ex periments were performed to obtain the impact force history from which the peak force was used to determine the extent of delamination crack length. The prediction of delami nation size using static fracture toughness was found to agree very well with the experi mental result.

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