Mining Mechanization Institute (Gliwice, Poland):

Brodny J., Professor, Doctor of Engineering Sciences, e-mail: jaroslaw.brodny@polsl.pl

The article discusses the results of studies aimed at improved performance of metal arch support in mine roadways, in particular, yielding of connection joints of support. The author presents theoretical evidence on physical and mathematical modeling of yielding joint in co-operation with metal sections in straight-line portions of arch support. The obtained results are compared with the standard bench testing results, which allows recommending the modeling method for optimization of current designs and engineering new designs of yielding support. The current yielding support designs feature unstable operation. Utilization factor of the current support strength is only 45% of the support maximum capacity [3]. As a consequence, to increase load-bearing capacity, more heavy-duty metal sections and increased number of fasteners are used, which slightly improves the support performance but greatly increases operational cost. Based on the bench tests, the key parameters of performance of a yielding joint are largely affected by the preliminary axial forces of fastening. Appropriate selection of fastening forces to interact in a joint of metal sections would create wide range of options for adjustment of load-bearing capacity of current supports. Such potential is offered by the developed theoretical model advisable for using in optimization of current designs of fasteners and in engineering their new designs.

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2. Brodny J. Wstepna analiza pracy polaczenia srubowego w zlaczu ciernym. Kwartalnik Akademii Gorniczo-Hutniczej, Gornictwo i Geoingynieria, Zeszyt 2. Krakow, 2010.
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