Rocks testing

Durst, P. 2002. Geochemical Modelling of the Soultz-sous-Forets Hot Dry Rock Test Site Coupling Fluid-Rock Interactions to Heat and Fluid Transport. PhD thesis. University of Neuchatel, 127 p. 

The purpose of die tests described on the paper of Missouri School of Mines (Ref 7) is to help in predicting expl performance in rock from performance in water. Four expls were tested both in water and in rock so that direct comparison of the results of the two methods of testing could be made. The rock tests were made at a granite quarry operated by the Consolidated Quarries Division of the Georgia Marble Co, near Lithonia, Ga. The rock was uniform with sp gr ca 2.6 and propagation velocity of about 18000 ft/sec. The underwater tests were made in a deep pond at the Armour Foundation test facility near Coal Ciry, Illinois. Water had sp gr 1.0 and propagation velocity 5000 ft/sec... 

The experiments have also demonstrated the flow reducing effect of fracture normal stress and fracture shear displacement on the fracture cross flow. Both fracture normal stress and fracture shear displacement seem to be of equal importance for the weakest rock tested. When the rock strength increases, the stress to strength ratio becomes the dominating factor, and fracture shear displacement seems to be of reduced importance. 

In 1978 discussion about the limit depth of cracks inside the Earth s crust took place in our Institute. The participants were J.R. Rice, B.V. Kostrov, the authors of this presentation, et al. The answer was found later when the rock testing data were collected, Nikolaevskiy (1979) and it was simple the Mohorovicic boundary is the limit depth for an open crack system. This conclusion contained, as one can see, also the genesis of the crust itself. The result of the following study is given below. 

According to the rock test standard proposed by International Society for Rock Mechanics (ISRM), the specimens were made into samples with size (j) 50 mm x 100 mm (Fig. 3). The tests were carried out by the TAW-2000 rock mechanics rigid servo-controlled testing machine at North China University of Water Resources and Electric Power (Fig. 4). 

B. Rocking test. Apply a horizontal force to the pole and attempt to rock it back and forth in a direction perpendicular to the line. Exercise caution to avoid causing power lines to swing together. Apply the force to the pole either by pushing it with a pike pole or pulling the pole with a rope. If the pole cracks during the test, it is unsafe. 

Recordkeeping Buckling at the ground line, Unusual angle to the ground, Cracks, Holes, Shell rot and decay, Knots, Depth of setting, Soft, wet, or loose soil, and Burn marks. A hammer and/or rocking test may also need to be conducted. None required. 

In this type of database data is stored in tables (entities) which are related to each other via identification numbers (ID). Due to the relations between datasets and the building of so called master tables, redundant data and mistakes (e.g. spelling mistakes) can be avoided. This model type supports and combines huge data volumes in a fast way and therefore it is suitable for a rock testing database. 

Lama RD, Vutukuri VS Series on rock and solid mechanics, Bd. II handbook on mechanical properties of rocks — testing techniques and results, Clausthal, 1978, Trans Tech Pubhcations. 

A hammer and/or rocking test may also need to be conducted. 

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