The focus of this paper is the thick soft rock mass roof track roadway in No. 3606 panel Chaili Coal Mine. Due to its substantial thickness, susceptible damage and deformation during mining process. In order preserve integrity roof, a full anchor cable support scheme proposed after studying mechanism bolt-anchor support. supporting parameters feasibility were determined through experience numer...

In coal mines, bolt loosening in the cage guide is affected by the harsh environmental factors and cage hoist vibration, leading to significant threats to work safety. It is crucial, to this effect, to successfully detect the status of multipoint bolts of guide structures. This paper proposes a system to monitor bolt status in harsh environments established based on the RFID technique. A proof-...

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...

Based on the engineering background of providing advance support for working face mining roadways, this paper studies reasonable technology roadway roofs by combining theoretical analysis, numerical simulation, and field tests. geological conditions 1304 Yineng Coal Mine, FLAC3D simulation software was used to compare analyze effects original single hydraulic prop bolt-mesh-cable without prop. ...

A mechanical study investigating the use of two different methods (grub and bolt screws) to secure external fixation half pins to circular frames. A four part experiment: (1) Grub and bolt screws were used to secure half pins in Taylor Spatial frames. Loosening torques were measured using a calibrated torque wrench. (2) Using universal testing machine (UTM), axial loading was applied to establi...

This study investigated the effects of oversized bolt holes on the properties of bolted connections with steel side members. The intent of the study was to determine (1) how well the European Yield Model (EYM) predicts experimental results for connections with oversized bolt holes and (2) how the loaddeformation behavior of connections is affected by oversized and/or misdrilled holes. Variables...

the load transfer mechanisms of cable bolts differ from those for normal rebar bolts. the cable bolts used in mines are basically steel strands with different constructions depending on the number of wires or elements and the way they are laid. tendon bolts (rebar and cable) are normally evaluated for their strength and load transfer properties. the tendon strength can be evaluated by the tensi...

Computer simulations are widely used in the truck industry in order to provide assistance in the product development. Bolt joints are common in trucks. A bolt fracture usually has a great influence on how a truck structure will behave in a crash. Therefore, when simulating truck crashes it is important to be able to predict when bolt fracture occurs. A material model for 10.9 bolts has been cal...

Bolt-nut connectors play an important role in the safety and reliability of structural systems. Stress concentration due to unequal load distribution can cause fatigue failure in bolt-nut connectors. In this paper, the stress distribution in bolt-nut connectors is studied using an axisymmetric finite element model. Various geometric designs proposed in the literature were studied to determine t...

Pre-stress degradation or looseness of rock bolts in mining or tunnel engineering threatens the stability and reliability of the structures. In this paper, an innovative piezoelectric device named a "smart washer" with the impedance method is proposed with the aim of developing a real-time device to monitor the pre-stress level of rock bolts. The proposed method was verified through tests on a ...