In this paper, the model test for the break angle and the breaking up of the shallow tunnel in soil and sand interbed are presented. Thus, analysing the mechanical behavior of rock mass, comparing some results of the formula with those of the model test.
Based on theory analysis and practical survey in testing ground,had studied influence factors such as caving height,work resistance of supports,coal seam rupture angle,main roof rotary angle and stopping mining time.
Presented in this paper is a design model for the elastoplasticity of anti slide piles. A stability analysis is carried out with the spatial failure wedge in the elastolastic part, deriving the equation for calculating the critical depth h c of the anchoring section of the piles, the plane and spatial solution to the crack angle θ.
When t→∞, the static-state distortion strain energy criteria and the formula for determiming static-state fracture angle are obtained.
In addition, the relative accuracy of three current fracture theories and the new criterion in predicting static-state mixed-mode initiation fracture loading and fracture angle in rock have been evaluated experimentally.
Perimortem injuries may be distinguished from postmortem damage by examining certain attributes such as fracture angle and fracture margins.
Numerical results for the fracture angle are obtained to illustrate the application of the proposed formulation.
The results showed a reduction in the mean fracture angle from 17° preoperatively to 1° postoperatively.
The maximum value (δmax) of the generator break angle is limited by the possibility of the existence of an attached compression shock, dc'.
According to these data a change in the generator break angle for the range δmin≤δ°≤δmax of the angle does not disrupt the nature of the flow in the separation zone, but only alters the size of this zone.
The article presents the results of tests with tubular specimens of aluminum alloy AMg6 subjected to simultaneous tension and internal pressure on a load trajectory in the form of two-link broken lines with the break angle of 90° in the stress space.