An exact dynamic 2D solution for a concentrated force near a stationary semi-infinite crack in an unbounded plane can be used in the transient analysis of wave-scattering problems. Direct approaches to obtaining the solution, however, are complicated by the existence of a characteristic length. A less direct approach is used here which circumvents these complications. As an example, the dynamic...

A new full field optical technique 'Coherent Gradient Sensing' (CGS) is developed and used to study crack tip deformations in transparent as well as opaque solids. A first order diffraction analysis is provided for the technique and its feasibility is demonstrated both in transmission and reflection modes. Preliminary results from the dynamic crack growth experiment clearly demonstrate the capa...

This study investigates the sensitivity of design variables such as ultimate strength of concrete, yield stress of reinforcing steel and damping ratio to the seismic response of staggered wall structures. Two different methods for sensitivity analysis, the tornado diagram method and the first-order second-moment method, are applied to two types of model structures. Non-linear dynamic analyses a...

This paper describes algorithms for threedimensional dynamic stress and fracture analysis using the material point method (MPM). By allowing dual velocity fields at background grid nodes, the method provides exact numerical implementation of explicit cracks in a predominantly meshless method. Crack contact schemes were included for automatically preventing crack surfaces from interpenetration. ...

Strain-rate effects on fracture behavior of unidirectional composite materials are studied. Single-edge notched multi-layered unidirectional graphite composites (T800/3900-2) are investigated to examine fracture responses under static and dynamic loading conditions using a digital speckle correlation method. The fracture parameters for growing cracks are extracted as a function of fiber orienta...