Impact of geometry of the powered roof support section on the rock mass

Szurgacz, Dawid

doi:10.1051/e3sconf/20187100001

Cited by 3 publications

(5 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this regard, the work uses the geometric model of the section. The model and the designations of individual geometric parameters are presented in Figure 3 [37,[41][42][43][44].…”

Section: Section Geometry Analysis Using a Simplified Modelmentioning

confidence: 99%

“…The ideal condition corresponds to the height at which the joints of the inclined canopy and the shield support are maintained. This height depends on the canopy inclination angle ( Figure 3) and is defined by the following dependent [37,41,43,44]:…”

Section: Section Geometry Analysis Using a Simplified Modelmentioning

confidence: 99%

“…In this case, the length of the legs (C) and their angles (α 4 ), as well as the length of the canopy support cylinder (Lc) and the angle of its inclination, must be related to the height h y of the section. These quantities are determined from the following equations [37,41,43,44]:…”

Section: Section Geometry Analysis Using a Simplified Modelmentioning

confidence: 99%

“…Even if the initial positioning of the section is correct, often the floor base and/or canopy shifts asymmetrically during the operation process. The most common cases of canopy and floor base incompatibility during operation are shown in Figure 4 [37,[41][42][43][44][45]. The sections often twist relative to each other (consequently, they are not parallel to each other) and to the axis perpendicular to the longwall surface.…”

Section: Section Geometry Analysis Using a Simplified Modelmentioning

confidence: 99%

“…Most of the activities related to testing of powered roof supports concerns the selection of sections for mining and geological conditions [3,10,[18][19][20][31][32][33] and testing of the section operating parameters (mainly pressure in the legs) at static and dynamic load [3,16,34,35]. A number of publications also concern the study of section design [12,32,[36][37][38][39] and support control systems [12,36,40].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Tests of Geometry of the Powered Roof Support Section

Szurgacz¹,

Brodny

2019

Energies

Self Cite

View full text Add to dashboard Cite

A powered roof support is a basic protection mean for longwall excavations in which highly efficient mining is carried out. The support operates properly when its individual sections are spragged correctly in a working and their operating parameters meet specific requirements. The geometry of the section, and in particular, the correct position of the floor base and the canopy, have a significant impact on the parameters and effectiveness of its work. Disturbances in this area, in many cases, are the cause of damage and improper operation of the support. Therefore, a new method of testing the position of the section in a longwall was developed based on an analysis of its geometry. The basis of this method are inclinometers (angle sensors) mounted on the main structural elements of the section. Recorded values of the angles of inclination of these elements and the developed analytical models are used to determine the positioning of the section in a longwall. The main purpose of the research was to develop a method that would allow, in the simplest possible way, the analysis of section geometry in real conditions. A simplified analytical model was used to determine the actual geometry of the section. It was used then as a basis of an analysis of possible states of the position of the section in the mining wall, including the surrounding rock mass. The results were applied during tests of the section carried out in a testing station and in real (underground) conditions. The developed measuring system helped to determine selected geometrical parameters of the section during these tests. The purpose of the research was to verify the developed model and demonstrate that the geometry of the section has a significant impact on its uneven loading. The obtained results, especially from underground tests, confirmed that during operation the support sections are twisted, which may cause overloading of their construction and disturbance of the operation process. The developed method of testing the geometry of the section is a new approach to analyzing the work of the powered roof support operating in variable mining and geological conditions. The developed method of testing the position of the section based on the angle of inclination of its individual elements is undoubtedly a new approach to this research area. The results obtained should be successfully used in practice to optimize the support section and when selecting support for specific working conditions.

show abstract

“…In this regard, the work uses the geometric model of the section. The model and the designations of individual geometric parameters are presented in Figure 3 [37,[41][42][43][44].…”

Section: Section Geometry Analysis Using a Simplified Modelmentioning

confidence: 99%

Section: Section Geometry Analysis Using a Simplified Modelmentioning

confidence: 99%

Section: Section Geometry Analysis Using a Simplified Modelmentioning

confidence: 99%

Section: Section Geometry Analysis Using a Simplified Modelmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Tests of Geometry of the Powered Roof Support Section

Szurgacz¹,

Brodny

2019

Energies

Self Cite

View full text Add to dashboard Cite

show abstract

Dynamics control of powered hydraulic roof supports in the underground longwall mining complex

Rudzki

Krot

2021

IOP Conf. Ser.: Earth Environ. Sci.

View full text Add to dashboard Cite

The study presents the dynamic analysis of the hydraulic cylinders operated in the powered roof support sections as an important part of the longwall underground mining complexes. This type of hydraulic unit is subjected to frequent shock impacts from the significant rock masses released on the top of mined caverns. Hydraulic props are equipped with safety valves with steel helical springs, which intend to reduce peak loads by the relief of internal pressure. These valves respond to shock with a time delay due to the limited velocity of the pressure wave inside the cylinder and an additional pipe of a small section, which restricts fluid flow in outer space. The new approach represented in this paper is based on mathematical modelling of the interaction of the hydraulic and mechanical parts and using additional signals to control safety valves. Detection of shock in advance (0.02-0.05 s) allows reducing pressure peaks by 30% and avoid failures. The challenges are the development of a “smart valve” with optimised control functions by the signals from additional sensors (vibration, deformation, piston position) and providing fast reaction time with a high flow rate under pressures up to 100 MPa.

show abstract

Analysis of Characteristics of Roof Fall Collapse of Coal Mine in Qinghai Province, China

Wang

Zhao

2022

Applied Sciences

View full text Add to dashboard Cite

This paper presents the roof fall collapse of a coal mine that occurred, causing 20 deaths and 1 injury, in Qinghai Province, China, on 14 August 2021. After the primary investigation of this incident and a brief description of the rescue action undertaken, this report discussed the possible reasons behind this disaster. The fissure water and damaged rock mass are the dominant triggering factors of this incident. Little concern for risk assessment and monitoring systems is one of the main man-made mistakes. Consequently, the reflections and suggestions are put forward to reduce or prevent the occurrence of roof fall incidents in coal mines. The noteworthy actions that are necessary in coal mine projects are conducting risk assessments based on geological condition and building proper support systems for coal mines considering he situation in situ.

show abstract

Impact of geometry of the powered roof support section on the rock mass

Cited by 3 publications

References 12 publications

Tests of Geometry of the Powered Roof Support Section

Tests of Geometry of the Powered Roof Support Section

Dynamics control of powered hydraulic roof supports in the underground longwall mining complex

Analysis of Characteristics of Roof Fall Collapse of Coal Mine in Qinghai Province, China

Contact Info

Product

Resources

About