Three-Dimensional Finite-Element Analysis of Chevron-Notched Fracture Specimens


Book Description

Stress-intensity factors and load-line displacements were calculated for chevron-notched bar and rod fracture specimens using a three-dimensional finite-element analysis. Both specimens were subjected to simulated wedge loading (either uniform applied displacement or uniform applied load). The chevron-notch sides and crack front were assumed to be straight. Crack-length-to-specimen width ratios (a/w) ranged from 0.4 to 0.7. The width-to-thickness ratio (w/B) was 1.45 or 2. The bar specimens had a height-to-width ratio of 0.435 or 0.5. Finite-element models were composed of singularity elements around the crack front and 8-noded isoparametric elements elsewhere. The models had about 11,000 degrees of freedom. Stress-intensity factors were calculated by using a nodal-force method for distribution along the crack front and by using a compliance method for average values. The stress intensity factors and load-line displacements are presented and compared with experimental solutions from the literature. The stress intensity factors and load-line displacements were about 2.5 and 5 percent lower than the reported experimental values, respectively. Raju, I. S. and Newman, J. C., Jr. Langley Research Center NASA-TM-85798, NAS 1.15:85798 RTOP 505-33-23-02...













Rock Dynamics and Applications 3


Book Description

Rock Dynamics – Experiments, Theories and Applications is a collection of scientific and technical papers presented at the Third International Conference on Rock Dynamics and Applications (RocDyn-3, Trondheim, Norway, 26-27 June 2018). The papers in the book reflect the recent developments in experiment and theory as well as engineering applications of rock dynamics. Rock dynamics studies the response of rock and rock masses under dynamic loading and during the state transition from static loading to kinetic movement. It also includes the study of engineering countermeasures to dynamic instability of rock and rock masses. The topics in the book include: - Dynamic theories - Numerical simulation - Propagation of stress waves - Dynamic tests of rock - Stability of underground openings under dynamic loading - Rockburst - Seismic monitoring - Dynamic rock support - Blasting - Earthquake-related rock structure damage, etc. Applications, such as rockburst, dynamic rock support, seismic monitoring, blasting and earthquake-related rock structure damage, are paid special attention in Rock Dynamics – Experiments, Theories and Applications. The papers, from specialists both from mining and tunnelling branches, discuss commonly interested dynamic issues. Their experience and knowledge in the application of rock dynamics are extremely valuable for all academics, engineers and professionals who work with rock dynamics.




Engine Structures


Book Description







Scientific and Technical Aerospace Reports


Book Description

Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.




Fracture of Brittle Disordered Materials: Concrete, Rock and Ceramics


Book Description

This book derives from the invited IUTAM Symposium in September 1993. The contributions discuss recent advances in fracture mechanics studies of concrete, rock, ceramics and other brittle disordered materials at micro and structural levels. It draws together research and new applications in continuum, damage and fracture mechanics approaches.