Rock burst support of deep rock mass has always been a difficult problem in geotechnical engineering. Aiming at the mass, new type pressure yielding and energy-absorbing bolt system is designed this paper. The energy absorption characteristics laminated spring members with different wall thicknesses were studied by static axial compression test drop hammer dynamic impact test. experimental resu...

In order to investigate the influence of various connecting systems on the buckling load of global shallow grid shells, stability analysis were performed in this chapter. Using all of the moment-rotation curves and load displacement curves which were performed in chapter 4, buckling behaviors could be simulated with special consideration to the nonlinear connection stiffness of various connecti...

Abstract Using the spatial structure of external staggered split-level panel layout, a combined support technology for adjacent roadways was developed and analyzed rock bolt anchor cable mechanism. The influence side parameters on mechanical properties anchorage body stress distribution lateral coal were revealed using FLAC 3D software. optimal bolts cables subsequently determined, effect gob-s...

INTRODUCTION Sliding hip screw fixation is well established in the treatment of trochanteric fractures of the hip. The X-Bolt Dynamic Hip Plating System builds on the successful design features of the sliding hip screw but differs in the nature of the fixation in the femoral head. A randomised pilot study suggested that the X-bolt Dynamic Hip Plating System might provide similar health-related ...

The aim of this study was to examine the behavioural and cranial/spinal responses of alpacas culled by captive bolt shooting and the resulting pathophysiology of captive bolt injury. Ninety-six alpacas were shot (103 shots) in a range of locations with a penetrating captive bolt gun (CBG). Ten (9.8%) alpacas were incompletely concussed following the first shot. No animals required more than two...

In this work, in order to analyze the load distribution on bolted joints, three different configurations of joints were modeled using the finite element method FEM, varying the joined parts and shim thickness, the intensity of the applied loads and the bolt diameter. All the proposed models are bi-dimensional, modeled with plate elements which present the same inertial moment of the parts in be...

In this paper, fatigue strength of the engine damper cap screw bolt is determined. Engine damper cap screw is critical fastener. Critical fastener is a term used to describe a cap screw that, upon failure, causes immediate engine shutdown or possible harm to person. So, determination of fatigue strength is important. S-N method is used for cap screw fatigue strength determination by testing num...

A simple, small-bolt method was developed and refined for evaluating and screening treatments being considered as prophylactics against bark beetles (Coleoptera: Curculionidae: Scolytinae). Using this method, 4 insecticide products (3 active ingredients) were evaluated against the southern pine beetle, Dendroctonus frontalis Zimmermann, intermittently during a period spanning 1 day to 9 months ...

The nuts and bolts problem is the following : Given a collection of n nuts of distinct sizes and n bolts of distinct sizes such that for each nut there is exactly one matching bolt, find for each nut its corresponding bolt subject to the restriction that we can only compare nuts to bolts. That is we can neither compare nuts to nuts, nor bolts to bolts. This humble restriction on the comparisons...

We discuss the lift of certain D6-antiD6-brane systems to M-theory. These are purely gravitational configurations with a bolt singularity. When reduced along a trivial circle, and for large bolt radius, the bolt is related to a nonsupersymmetric orbifold type of singularity where some closed string tachyons are expected in the twisted sectors. This is a kind of open-closed string duality that r...