fast fracture is one of the major failure modes in brittle polymers. generally, crack growth in these polymers may occur under combined tensile-shear loading. however, the fracture test data reported previously for some dental restorative resins can not be predicted by using the available fracture criteria.in this paper, a modified fracture criterion is used for estimating the fracture load for...

This letter describes a newly discovered phenomenon: ductile fracture in cementitious materials. The brittle nature of materials such as concrete and ceramics has prompted the development of various approaches to enhance their fracture toughness. Fibre reinforcement has been the common focus in the toughening of the brittle materials. Two types of fracture have been observed to date in cementit...

The characterization of hydraulic transmissivity of permeable fracture reservoirs is a very important task in the exploration of water resources and hydrocarbons. Previous studies that model the permeable structure as a single fluid-filled fracture failed to explain the observed significant Stoneley wave attenuation across the permeable structure. In this paper, the structure is modeled as a pe...

Ž . Ž . Cluster variable aperture CVA simulated annealing SA is an inversion technique to construct fluid flow models in fractured rocks based on the transient pressure data from hydraulic tests. A two-dimensional fracture network system is represented as a filled regular lattice of fracture elements. The algorithm iteratively changes element apertures for a cluster of fracture elements in orde...

Mode I, quasi-static, steady state crack growth is analyzed for rate dependent materials under plane strain conditions in small scale yielding. The solid is characterized by an elastic-viscoplastic constitutive law and the plane ahead of the crack tip is embedded with a rate dependent fracture process zone. The macroscopic work of fracture of the material is computed as a function of the crack ...

The structural reliability of many brittle materials such as structural ceramics relies on the occurrence of intergranular, as opposed to transgranular, fracture in order to induce toughening by grain bridging. For a constant grain boundary strength and grain boundary toughness, the current work examines the role of grain strength, grain toughness, and grain angle in promoting intergranular fra...

In 1995, the Hyogoken-Nanbu earthquake (M 7.3) ruptured the Nojima fault, Awaji Island, central Japan. To investigate the recovery process of a fault zone after a large earthquake, repeated water injection experiments have been conducted every few years in an 1800-m-long borehole near the Nojima fault since 1997. In addition, the groundwater discharge rate and pressure have been observed in an ...

Trabecular bone fracture is a traumatic and localized event studied worldwide in order to predict it. During the years, researchers focused over the mechanical characterization of the trabecular tissue to understand its mechanics. Several studies pointed out the very local nature of the trabecular failure, finally identifying the fracture zone with the aim to study it separately. The complexity...

in this paper, hardness and tensile properties of welded zone of aluminum 1100 alloys by friction stir welding process was investigated and the effects of rotational and traverse speeds of tool on these parameters was studied. also the fracture cross-section of welded samples was investigated. according the results of this paper, the hardness of weld material is higher than base material and is...

the experimental study and modeling of gravity drainage during water alternative gas injection, wag process, in carbonate rock for one of the iranian off-shore reservoir at lab-scale were carried out. the mechanism of gravity drainage during the wag process, and its contribution to the oil recovery in the fractured carbonate reservoirs were also studied. in the wag process alternatively gas is ...