One of the obstacles in making in situ measurements, especially in severe environmental conditions, is lack of a relatively low cost apparatus used for acquiring and recording data. These severe conditions are frequently met in coal mines where rock bolts are installed to support roof sections. Because of this the aim of the work undertaken by the author at the first stage was inventing and constructing of a portable measurement system. As a programming tool the LabVIEW program was used and as hardware a DAQ card (data acquisition card) installed on a laptop platform and worked out conditioning signal unit were introduced to the measurement chain. After that stage a process of calibrating was realized and comparison of results with those obtained on a laboratory stand was made. Having the apparatus validated the data base of different cases of discontinuity of a cement layer, when rock bolts are grouted into a rock, were calculated. Finally measurements in real working conditions were performed and condition of grouted rock bolts was check out.
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