Construction Testing Services

· Pull-out tests on mine/quarry roof bolts.

· Pull-out tests on grouted rebar for civil construction projects.

· Pull-out test device calibration.

· Pull -out tests on rebar/bolts anchored in concrete.

· Pull-out tests can be done on rebar/bolts anchored in concrete to determine the physical strength of the rebar/bolts. The testing procedure is intended to determine if the rebar/bolts can withstand a  pre-determined tensile pull and whether there is any slippage of the rebar/bolt or any cracking of the concrete around the rebar/bolt.

· The pull – out tests are conducted using a Dayton, 10, 000 lb/in² capacity hydraulic hand pump.  The hydraulic hand pump is attached to a pull–out device, consisting of a steel lower platen with two 5 ton Enerpac hydraulic cylinders, an upper steel platen is attached to the Enerpac cylinders with a cut out in the middle so that the rebar/bolt can be placed between two hemispherical grips.

· Specimen load is measured by a hydraulic pressure gauge that is incorporated into the hydraulic hand pump. The hydraulic pressure gauge was previously calibrated (summary, linear regression graph) to correlate the pressure generated by the pump to the pull – out force of the hydraulic cylinders.

· A pre-determined axial load is then applied to the rebar/bolt and held for a pre-determined time period. The load, cumulative test time, and position of the rebar/bolt is continuously monitored.  The rebar/bolt movement, defined as a change in distance between the upper and lower platen, is monitored to the nearest 0.001” using a dial gage micrometer. 

· Laboratory Testing of Concrete Cylinders.

· The intent of the testing program is to determine the    compressive strength of the concrete cylinders.

·  The individual concrete cylinders are previously poured into 6” x 12” plastic concrete test cylinders.  After curing for 24 hours, the plastic test cylinders are then removed from the concrete and then submerged in lime water.  The uniaxial specimen ends are then capped with sulfur. The specimen preparation is carried out according to ASTM (C31/C31M-03) standard test procedures.

·   Specimens are then tested using a SATEC, closed‑loop, hydraulically driven, testing frame.  The frame has a 200,000-pound capacity and is externally con­trolled by a PC that is also used for data acquisition.

·   The uniaxial compressive strength is calculated as the load at failure divided by the specimen area.

[ Home ] [ Up ] [ Bolts ] [ Summery ] [ Linear Regression Graph ] [ Pull-Out Device ]

Send mail to with questions or comments about this web site.
Copyright © 2007 Appalachian Mining & Engineering
Last modified: 07/10/07