The article gives a description of the developed design of a sample of the connection of wooden elements, which is devoid of the shortcomings of existing technical solutions that allow simulating the actual operation of real wooden structures. The design makes it possible to increase the reliability of the test results, simplifies the test procedure and the test results processing process. The developed design of the sample fully reflects the actual work of the real joints of the beam cage of a wooden building, causes a stress-strain state in the sample, to a large extent similar to the stress-strain state of a real joint due to the correct application of the basic provisions of the similarity theory to connect the model with the full-scale construction of a wooden buildings, schemes for applying the load to the sample and methods for conducting experiments.

Keywords: wooden structures, timber, joining of wooden elements, testing of a sample of connecting wooden elements, wooden beam, main beam, secondary beam, metal plates, screws, reliability improvement

The article describes four developed designs of samples of joints of solid wood elements on aluminum linings. They made it possible to simulate the operation of real connections of the main and secondary beams, as well as crossbars and columns. Tests of connection samples were carried out, one of the four developed variants of sample designs was selected that most fully reflects the actual work of real joints of wooden elements. The strength and deformation characteristics of the joint, the upper boundary of the elastic work area (VGOUR) of the joint are determined. Based on the conducted research, the peculiarities of the work of the studied compounds were determined, a sample of the connection of a wooden element with a metal overlay was developed, which allowed the development of measures aimed at increasing the bearing capacity and reducing the deformability of the studied compounds without significant material costs associated with the purchase of expensive SHERPA linings.

Keywords: solid wood, metal slips, testing of joint specimens, joint bearing capacity, joint deformability, upper limit of the elastic work region, full deformation, permanent deformation, elastic deformation, safety factor

The article presents the results of comparative tests of samples of connections of wooden elements from glued wood on metal linings using screwed and glued screws, 3 samples of each of 5 types of connections (one glueless and four varieties of glued screwed connection). It has been established that the use of epoxy adhesives increases the strength characteristics of the adhesive-free joint by the criterion of breaking load by 1.46, 1.78, 1.70, 1.59 times, by the criterion of the elastic work of the joint by 1.56, 1.56, 1.82, 1.30 times for glued joints (ED-20 + PEPA, ED -20 + THETA, DER-331 + PEPA, DER-331 + THETA) respectively. Of the glued-in samples, the deformation Dult=2mm was achieved only by samples No. 8 (ED-20 + TETA) and No. 14 (DER-331 + TETA) at loads 1.77, 1.40 times greater than the load in a glueless joint. Full deformations Dp at the same load within the limits of elastic work of joints decrease by 7, 10.61, 10.61 times for glued joints (ED-20 + PEPA, ED-20 + TETA, DER-331 + PEPA), respectively. For samples of compounds (DER-331 + TETA) with a compared load value, the deformations are equal to 0.

Keywords: glued wood, metal linings, testing of joint samples, bearing capacity of the joint, deformability of the joint, upper limit of the elastic work region (URL), total deformation, permanent deformation, elastic deformation, safety factor

The article describes the developed design of a sample of joining solid wood elements on SHERPA plates, which made it possible to simulate the operation of nodal junctions of the main and secondary wooden beams for frame buildings and structures. A procedure for testing specimens by loading in steps with periodic unloading has been compiled and tested on three test specimens. The tests of the approved sample of the joint were carried out, its maximum bearing capacity was established, as well as the load corresponding to the upper boundary of the elastic work area (VGOUR) of the joint. The graphs of dependencies were built: "Load - total deformation Dp", "Load - permanent deformation Dо", "Load - elastic deformation Dу", "Elastic deformation Dу - residual deformation per cycle dо". The deformations of the joint were determined within the limits of the bearing capacity of the sample, the calculated bearing capacity of the joint and the coefficient of transition from glued wood to solid wood.

Keywords: solid wood, SHERPA metal strips, test of a specimen of a joint of wooden elements, load-bearing capacity of the joint, deformability of the joint, upper limit of the elastic work area of the joint, total deformation, permanent deformation