Device, system and method for dynamic testing of ground support bolts, anchor bolts or rock bolts

Patent metadata

Field	Value
Publication number	US-2016025608-A1
Application number	US-201414765725-A
Country	US
Kind code	A1
Filing date	Feb 5, 2014
Priority date	Feb 5, 2013
Publication date	Jan 28, 2016
Grant date	—

Abstract

A connector, an associated dynamic testing system and method for testing rock bolts or rock anchors in situ. The connector is attached to a rock bolt/anchor and supports a hanging load via a shaft. The connector has a body of two halves retaining upper first and lower second connectors having respective curved surfaces. Each of the two halves has a curved inner surface allowing limited relative rotational movement of the first and second connectors relative to the two halves when a load is applied. A load cell and accelerometer register the load applied to the rock bolt/anchor through the connector and any resulting movement of the rock bolt/anchor.

First claim

1 . A connector to attach a loading device to an in situ rock bolt or anchor bolt in a rock or concrete substrate, the connector comprising:
a body including multiple portions that are releasably connectable together by one or more integral or detachable fastening means; a first attachment means arranged to attach the body to an in situ rock bolt or anchor bolt; and a loading device connection, wherein the loading device connection includes a second attachment means arranged to releasably attach the loading device to the body.

2 . (canceled)

3 . (canceled)

4 . The connector according to claim 1 , wherein the connector includes at least one first curved surface within a cavity in the body, and a corresponding second curved surface associated with the first attachment means.

5 . The connector according to claim 1 , further comprising a third curved surface within a cavity of the body, and a fourth curved surface to contact the third curved surface to allow relative movement of the loading device and the body.

6 . The connector according to claim 4 , wherein the cooperating first and second curved surfaces includes complimentary part spherical surfaces.

7 . The connector according to claim 5 , wherein the cooperating third and fourth surfaces includes complimentary part spherical surfaces.

8 . The connector according to claim 1 , wherein the first attachment means includes rock bolt connection means arranged to attach the connector to the rock bolt.

9 . The connector according to claim 1 , further comprising an adapter for connection of the first attachment means to the rock bolt or anchor bolt.

10 . The connector according to claim 1 , wherein the rock bolt connection means includes an aperture to receive a shaft portion of the rock bolt.

11 . The connector according to claim 1 , wherein the fasteners include at least one retaining plate or ring with holes therethrough to receive bolts.

12 . The connector according to claim 11 , wherein the bolts pass through aligned holes on each plate or ring, and nuts attached to the bolts or engagement of the bolts to threaded holes in the plates/rings retain the two portions together.

13 . The connector according to claim 1 , further comprising at least one accelerometer or at least one load cell.

14 . The connector according to claim 13 , wherein the at least one accelerometer is housed in the connector body.

15 . The connector according to claim 13 , wherein the at least one load cell is provided adjacent the second attachment means.

16 . The connector according to claim 1 , wherein the connector includes a tapered opening to the first attachment means and/or a tapered opening to the second attachment means.

17 . The connector according to claim 1 , further including means to prevent damage to an electrical connector of a load cell provided within the connector.

18 . The connector according to claim 17 , further comprising at least one metal projection adjacent the electrical connector.

19 . The connector according to claim 18 , wherein the at least one metal projection includes a bolt projecting above the load cell electrical connector and a tab of a washer projecting below the load cell electrical connector.

20 . A dynamic testing system for testing rock bolts and anchor bolts in situ, the system including a loading device and a connector to releasably attach the loading device to an in situ rock bolt or anchor bolt, the loading device including at least one releasable weight to apply an impact load through the connector to the rock bolt or anchor bolt when released, and a weight release device, the connector including at least two portions releasably connectable together.

21 . The system of claim 17 , further comprising a connector including a body having multiple portions that are releasably connectable together by one or more integral or detachable fastening means, a first attachment means arranged to attach the body to an in situ rock bolt or anchor bolt, and a loading device connection, wherein the loading device connection includes a second attachment means arranged to releasably attach the loading device to the body.

22 . A method of testing a rock bolt or anchor bolt in situ, the method comprising the steps of:
connecting a connector to an exposed portion of the rock bolt or anchor bolt; attaching a weight drop assembly to the connector; and providing a weight release mechanism to remotely release the weights during testing, the connector including at least one curved surface allowing the weight drop assembly to hang at or near vertical if the rock bolt or anchor bolt in situ is not vertical.

Assignees

• Sandvik Intellectual Property

Inventors

• Darlington Bradley
• Karlsson Marten Bjorn
• Rataj Mieczyslaw

Classifications

• G01N3/303 Primary

  generated only by free-falling weight · CPC title

• G01M7/08

  Shock-testing · CPC title

• E21D21/0093 Primary

  Accessories · CPC title

• F16B7/0426

  for rods or for tubes without using the innerside thereof · CPC title

• G01L5/00

  Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes · CPC title