
1 2 This test method is under the jurisdiction of ASTM Committee D 18 on Soil For additional information see Suggested Method for Determining the and Rock and is the direct responsibility of Subcommittee D18 12 on Rock Strength of a Rock Bolt Anchor Pull Test Suggested Methods for Rock Bolt Mechanics
Rock bolts are generally exposed to a combination of shear bending and tension that can cause the bolt to deform with increasing joint displacement potentially leading to failure In spite of these combined effects only tensile capacity is currently considered in design and testing
Testing of rock bolts in full scale laboratory controlled conditions is therefore of great importance At the rock mechanics laboratory of SINTEF and Norwegian University of Science and Technology NTNU in Trondheim a rock bolt test rig has been developed for full scale testing for pull shear and combination pull shear tests
Rock Bolt Dollies Rock bolt installation dollies should only transfer rotational energy to the rock bolt during installation not percussive energy when stopers and jacklegs are used The shank end of the dollie must be short enough to avoid contact with the drill piston Typically these rock bolt dollies have a 7 8 quot hex shank and are only 31 4 quot long
Test Results The test results will be categorized as follows Category 1 A perfect bolt in perfect rock conditions this will rarely occur Category 2 A bolt which we consider is serviceable in that it has good anchorage good load transfer along the length of the bolt and reasonable rock grout resin contact Category 3
They are used for destructive and non destructive tests of the different types of bolts By exchanging the gripping head our test equipment can be adapted for different types of bolts expansive split set corrugated etc The bolt tensile test is a very important test to check the quality of the bolts and the correct installation of this thus guaranteeing the optimum
The CT Bolt ™ is a unique combination rock bolt system It offers the combined advantages of an immediate point anchorage and subsequently a fully grouted rock bolt A two step installation procedure allows fast installation and immediate anchorage separate and independent grouting provides flexibility in regard to working cycles
2022 2 16 nbsp 0183 32 The rock bolt test rig was developed in 1995 and has since been regularly upgraded The purpose of the rig is to investigate the mechanical performance of different rock bolts when subjected to different loading
2016 4 1 nbsp 0183 32 Fig 1 Rock bolts installed in the rock left A typical grouted rock bolt right 2 Guided waves in a rock bolt The term guided waves refers to the ultrasonic waves that propagate in solid media with hard boundaries This type of ultrasonic waves is subject to both reflection and refraction with the boundary of the solid which results in mode conversion between
0 40 quot 10 16 mm Thread Size left and right I All Bolts 5 8 11 UNC 3 4 10 UNC 7 8 9 UNC All dimensions in accordance with ASTM F432 amp CSA M430 90 specifications Technical Data C1060 Steel
Rock bolt testing Our team at ME SAFE has had extensive experience with rock bolt failures in Australian underground mines and developed methods to secure these failures These methods have been successfully employed over the past
2014 3 1 nbsp 0183 32 1 1 The objective of this test method is to determine the time over which rock bolt tension decreases from the installed value to a designated minimum value 1 2 This test method is applicable to any anchor system which is not fully encapsulated immediately upon installation including mechanical cement grout resin epoxy polyester and the like or other similar
2020 9 10 nbsp 0183 32 1 11 The calibration data for each load cell test jack pressure gauge and 2 master pressure gauge to be used in the proof testing in accordance with 3 the calibration requirements specified in Section 6 17 3 3 4 5 Rock Bolt and Rock Dowel Preconstruction Conference 6 A rock bolt and rock dowel preconstruction conference may be held at the
2017 4 5 nbsp 0183 32 Several rock bolt testing system were developed over the last two decades that were specialized for non destructive testing of rock bolts Some of them are commercially available and some are undergoing prototyping and testing The Boltometer concept was proposed by Geodynamik in Sweden
1996 3 25 nbsp 0183 32 OF TESTING SHOTCRETE AND ROCK BOLTS R B CLAY and A P TAKACS Dar Al Handasah Adana Turkey 25 th March 1996 Abstract
2013 10 2 nbsp 0183 32 A rock bolt basically holds surface rock formations to the parent rock massive It may retain the surface rock blocks in tension typically for tunnels It may retain the rock face in shear usually for cliff faces rock cuttings and over hangs Initially we considered that 25 mm or even a 50 mm diameter rock bolt would be too slender to test
2016 9 12 nbsp 0183 32 DEGREE PROJECT IN CIVIL ENGINEERING AND URBAN MANAGEMENT SECOND CYCLE 30 CREDITS STOCKHOLM SWEDEN 2016 Pullout test of rock bolts at the Lima Hydropower station Assessment of the test method JAKOB LJUNGBERG KTH ROYAL INSTITUTE OF TECHNOLOGY SCHOOL OF ARCHITECTURE AND THE BUILT
2009 2 17 nbsp 0183 32 0kN 44 8kN Rock edge failure this test block had a number of other test holes drilled in it and the bolt was less than 50mm from the edge After block failure Simulated lead falls bolt in Test conditions Dry indoors Air Temp
Rock Bolt Pull Out Test Apparatus Specification The objective of the test method is to measure the working and ultimate capacities of rock bolt anchors The
2022 1 5 nbsp 0183 32 in contact with the wedge grips In such rocks the use of resin cartridge anchors described later in this chapter is recommended At the other end of the rockbolt from the anchor a fixed head or threaded end and nut system can be used In ei ther case some form of faceplate is required to distribute the load from the bolt onto the rock
2021 5 7 nbsp 0183 32 Rock bolt testing has been carried out for many years It provides essential information regarding failure modes how rock bolts act in fractured rock masses and loading conditions The test allows miners in a fully monitored and controlled way to shear or pull the bolts to loads that are beyond their capacity
Anchors Rock Bolts amp Pre Support The CT Bolt ™ is a unique combination rock bolt system It offers the combined advantages of an immediate point anchorage and subsequently a fully grouted rock bolt A two step installation procedure allows fast installation and immediate anchorage separate and independent grouting provides flexibility in
Over 50 000 Rock Bolts Tested Non destructive testing of rock bolts strands dowels and Tie bars Identifies defects such as lack of grout and corrosion of bars Measures the Safe Additional Loading SAL as the pull off load
OF TESTING SHOTCRETE AND ROCK BOLTS R B CLAY and A P TAKACS Dar Al Handasah Adana Turkey 25 th March 1996 Abstract Shotcrete is frequently used with rock bol ts as support for
rock bolt test rig has been developed for full scale testing for pull shear and combination pull shear tests This paper describes the principles behind this quasi static full scale testing and includes the results and analyses of recent tests performed
2020 9 10 nbsp 0183 32 1 11 The calibration data for each load cell test jack pressure gauge and 2 master pressure gauge to be used in the proof testing in accordance with 3 the calibration requirements specified in Section 6 17 3 3 4 5 Rock Bolt and Rock Dowel Preconstruction Conference 6 A rock bolt and rock dowel preconstruction conference may be held at the
2021 1 25 nbsp 0183 32 Two identical smart rock bolt prototypes were tested in the test tunnel of an underground research laboratory The testing setup used two methods to test these prototypes pull out force and heat flux applied to the rock mass via rope heaters inserted into symmetrically located boreholes around the smart rock bolt
For Annual Book of ASTM Strength of a Rock Bolt Anchor Pull Test Suggested Methods for Rock Bolt Standards volume information refer to the standard s Document Summary page on Testing International Society for Rock Mechanics Commission on Standardization the ASTM website of Laboratory and Field Tests 1974
2014 3 1 nbsp 0183 32 5 3 3 The design load and installation load on the rock bolt system should be predetermined The installation load is less than the anchor capacity as determined by Test Method D4435 The design load is less than the installation load the amount depends on rock properties and the minimum time required to encapsulate the bolts