FIELD: civil engineering, mining. SUBSTANCE: method for determining soil strength includes building calculated cross section of pit slope under investigation. Then base gallery to be strained and calculated line are determined on the basis of data of natural measurements and geological exploration. Then calculated sections stressed to different extent are selected, and soil shift tests are carried out. Soil samples are selected from each calculated section, and placed in shifting holders of rectangular cross sections to carry out the tests. Number of the holders corresponds to number of the calculated sections. The holders are connected in series. Length of the holders is proportional to scaled length of calculated slide line portion for each calculated section. Length of lower holder 13 is larger than that of upper holder 11 in the direction of shift. Bare sample surface in lower holder 24 is treated to the state of slide surface. Loading to a sample in each holder is accepted average for a proper individual calculated section. Decomposition of forces on slope slide surface and nature forces are accounted. Experimental tests for individual and combined concurrent shifts of all the samples to define summary peak and stable resistance to shift in the process of holder moving at constant speed are conducted preliminary after sample selection. Type of holder joints is selected depending on mechanism and slope shift conditions applied. Main tests are carried out according to scheme of concurrent and combined shift with the least values of summary resistance to shift were obtained. Device to implement this method has upper movable holders 11 being extensible in length, and lower immovable holders 13 fixed in bedframe 20. The holders are installed in one line and may be connected with flexible pullers 17. Removable layers 18 may be placed between them. The holders have individual stamps 15. EFFECT: high reliability. 2 cl, 4 dwg, 7 tbl
