<abstract xmlns="http://www.w3.org/1999/xhtml">This article presents the methodology and results of single shear tests of bolt rods under dynamic impact loading generated by means of a drop hammer. Comparative analysis was also performed for bolt rod load capacity, stress and shear work under static and dynamic (impact) loading. The developed method of single shear testing of bolt rods under impact loading makes it possible to obtain repeatable test results concerning maximum bolt rod shearing force, shear stress and shear work values.Comparative shear tests of four types of bolt rods under static and impact loading showed that the APB-type bolt rods made of AP770 steel, which was characterised by having the highest strength, exhibited the greatest shear work. AM22-type bolt rods exhibited a very similar work value. Though the AM22-type bolt rods made of A500sh steel demonstrated lower strength than the APB-type bolts, as well as a smaller diameter and cross section, they dissipated the impact energy better thanks to their higher plasticity. This could indicate the direction of optimisation for bolt rods in order to increase their impact strength.Mathematical relationships were also formulated for selected tests, describing the real single shear courses F d =f(t) of bolts under impact loading. The obtained relationships could be applied in the load assessment process of bolt rods intended for use under roof caving, tremor and rock burst conditions.</abstract>

This article presents the methodology and results of single shear tests of bolt rods under dynamic impact loading generated by means of a drop hammer. Comparative analysis was also performed for bolt rod load capacity, stress and shear work under static and dynamic (impact) loading. The developed method of single shear testing of bolt rods under impact loading makes it possible to obtain repeatable test results concerning maximum bolt rod shearing force, shear stress and shear work values.Comparative shear tests of four types of bolt rods under static and impact loading showed that the APB-type bolt rods made of AP770 steel, which was characterised by having the highest strength, exhibited the greatest shear work. AM22-type bolt rods exhibited a very similar work value. Though the AM22-type bolt rods made of A500sh steel demonstrated lower strength than the APB-type bolts, as well as a smaller diameter and cross section, they dissipated the impact energy better thanks to their higher plasticity. This could indicate the direction of optimisation for bolt rods in order to increase their impact strength.Mathematical relationships were also formulated for selected tests, describing the real single shear courses F d =f(t) of bolts under impact loading. The obtained relationships could be applied in the load assessment process of bolt rods intended for use under roof caving, tremor and rock burst conditions.

Comparative Shear Tests of Bolt Rods Under Static and Dynamic Loading

Studia Geotechnica et Mechanica

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

{"article-title":"Comparative Shear Tests of Bolt Rods Under Static and Dynamic Loading"}

This article presents the methodology and results of single shear tests of bolt rods under dynamic impact loading generated by means of a drop hammer....

Comparative Shear Tests of Bolt Rods Under Static and Dynamic Loading

Article Category: Research Article

Published Online: Jun 30, 2020

Page range: 151 - 167

Received: Nov 20, 2019

Accepted: Jan 29, 2020

DOI: https://doi.org/10.2478/sgem-2019-0038

Keywords
rock bolt, laboratory bolt test, static and dynamic single shear test, shear work

© 2020 Andrzej Pytlik, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Comparative Shear Tests of Bolt Rods Under Static and Dynamic Loading

Article Category: Research Article

Published Online: Jun 30, 2020

Page range: 151 - 167

Received: Nov 20, 2019

Accepted: Jan 29, 2020

DOI: https://doi.org/10.2478/sgem-2019-0038

Keywordsrock bolt, laboratory bolt test, static and dynamic single shear test, shear work

© 2020 Andrzej Pytlik, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
rock bolt, laboratory bolt test, static and dynamic single shear test, shear work