Fracture energy release and size effect in borehole breakout

1993 ◽  
Vol 17 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Zdeněk P. Bažant ◽  
Feng-Bao Lin ◽  
Horst Lippmann
Keyword(s):  
Size Effect ◽  
Fracture Energy ◽  
Energy Release ◽  
Borehole Breakout

Size effect on fracture energy of concrete

1990 ◽  
Vol 35 (1-3) ◽  
pp. 107-115 ◽  
Author(s):  
F.H. Wittmann ◽  
H. Mihashi ◽  
N. Nomura
Keyword(s):  
Size Effect ◽  
Fracture Energy

Test Study of Fracture Mechanical Properties of Reactive Powder Concrete with Additives

2014 ◽  
Vol 904 ◽  
pp. 3-6 ◽  
Author(s):  
Zhi Gang Yin
Keyword(s):  
Mechanical Properties ◽  
Energy Release Rate ◽  
Fracture Energy ◽  
Energy Release ◽  
Release Rate ◽  
Fracture Behavior ◽  
Fracture Model ◽  
Reactive Powder Concrete ◽  
Critical Crack Length ◽  
Reactive Powder

The different influencing regular of fly-ash fractiontype of fibre (steel fibre and polypropylene fibre) and fibre fraction on the mechanical property and fracture behavior of Reactive Powder Concrete (PRC) are studied. Fracture mechanical properties of RPC is researched in double-K fracture model and fracture energy release rate G . Test results show that the crack propagation of RPC with steel fibers is limited. Its fracture toughness and pre-critical crack length is largely enhanced. Double-K fracture model and fracture energy release rate G are consistent with describing the fracture behavior of RPC.

MULTIFRACTAL FRACTURE AND SIZE EFFECT

Fractals ◽  
1994 ◽  
Vol 02 (02) ◽  
pp. 245-248 ◽  
Author(s):  
ALEXEI MOSOLOV
Keyword(s):  
Stress Distribution ◽  
Size Effect ◽  
Fracture Energy ◽  
Fractal Geometry ◽  
Critical Stress ◽  
Scaling Laws

The fractal geometry is applied to describe the size effect in the fracture. We proposed a multifractal model for stress distribution in inhomogeneous solids and obtained the exponents in the scaling laws for the critical stress as well as for the apparent fracture energy. These exponents are connected with parameters of fractal geometry of damage.

Acoustic emission measurements and lattice simulations of microfracture events in spruce

Holzforschung ◽  
2010 ◽  
Vol 64 (4) ◽  
Author(s):  
Edwin Nagy ◽  
Eric N. Landis ◽  
William G. Davids
Keyword(s):  
Acoustic Emission ◽  
Fracture Energy ◽  
Energy Release ◽  
Lattice Model ◽  
Failure Modes ◽  
Mechanical Damage ◽  
Peak Strain ◽  
Cumulative Energy ◽  
Ae Energy ◽  
Total Fracture

Abstract A statistical lattice model was developed to investigate the energy associated with damage and failure of wood. The model incorporates several important morphological aspects of wood such as grain direction, early wood percentage and grain geometry. The model was developed to investigate progressive damage under enforced boundary displacements and has been adapted to predict fracture energy related phenomena. In this particular study, notched specimens were loaded in uniaxial tension while monitored by a passive acoustic emission (AE) measurement system. The energy associated with the mechanical damage was measured by the AE instruments and compared with the energy released by ruptured elements in the lattice model. Cumulative energy release was tracked as a function of specimen load and deformation in both model and experiment. A ratio was established between the cumulative AE energy released at the first drop in load and the cumulative fracture energy released when the model load-deformation relationship becomes significantly non-linear. An additional ratio was established between the total fracture energy measured prior to 50% of peak strain and the total fracture energy measured prior to peak strain. The magnitudes of these energy release ratios vary owing to a change in failure modes between the short model and the larger specimens; however, the shape of the AE energy release curve up to failure coincides well with that predicted by the model simulations.

Sign in / Sign up

Export Citation Format

Share Document