Article shows results of anchor pullout tests for two types of anchors: bent foundation anchor bolt and torque-controlled undercut anchor. Effective embedment depth is determined during research for bent anchors 16, 24 and 36 mm in diameter. Tests were carried out for 37 specimens with different embedment depth in a range from 150 to 650 mm. Load-displacement diagrams for static and cyclic dynamic pullout tests in uncracked and cracked concrete were acquired. Cyclic loading pattern simulated seismic loads. Test results for undercut anchors with diameter of 12, 16 and 20 mm and embedment depth of 125, 190 and 250 mm respectively allowed to estimate the influence of cracks in concrete and cyclic loads on ductility of anchor during pullout tests. It is stated that embedment depth required by regulatory documents for bent anchor bolt is higher than admissible embedment depth acquired in tests as a result of comparative analysis of design and optimal anchor bolt structure.

Abstract. The article presents the results of the experimental determination of the physical and mechanical characteristics of rubber-metal vibrationproof supports used in the construction of facilities in the areas of increased seismic hazard. The testing was based on two necessities: to substantiate the possibility of using such a constructive seismic protection solution and to create reliable calculation models of the structures with rubber-metal support. More than thirty samples were tested in the laboratory under various loads and impacts. The elastomers were tested in accordance with the requirements written in EN-1337-3. The experiment was performed on three types of elastomer model samples to determine their vertical and horizontal stiffness, the tensile strength and modulus of elasticity and creep. The work was performed on INSTRON power equipment and a test rig equipped with MTS hydraulic jacks installed in the power frame. The testing results of elastomeric support models were confirmed by the determination of individual characteristics on the full size specimens at the corresponding load. Thus, the test has confirmed and proved the validity of the use of elastomeric bearings for seismic protection of a mall construction.

Mechanical properties of specimens were researched for model analysis of stress-strain behavior in the stress concentration zone for plate structures using aluminum alloys. Traditional and new structure materials including Russian (1915T and 1565ch) and foreign (6082 – Russian analogue AD35) developments with different alloyage systems (Al-Mg, Al-Mg-Si and Al-Zn-Mg accordingly), strengthening methods, corrosive resistances and welding capacities are studied. Strain and fracture resistance is shown for axial and eccentric tension and for impact bending in the temperature range from -70 to +20°C. Acquired results allow us to designate loads reasonably for structure design using aluminum alloys and estimate their durability.

The article includes results of shear test of rubber-metal seismic insulators (elastomers) for different service actions. Research shows influence of low temperatures, material aging and cyclic loads on horizontal stiffness and shear modulus of elastomers. Tests were carried out according to existing Russian and foreign regulatory documents. An insignificant decrease in elastic properties of elastomers is seen after aging and cyclic loading. Influence of low temperatures increases stiffness of elastomers by 23%.

The article addresses mechanisms of anchorage failure in a concrete base studied within the framework of physical experiments. The authors investigated the most frequently used types of anchors, such as the cast-in-place and post-installed ones. The anchorages were studied under static and dynamic loading, similar to the seismic type. During the experiments, the post-earthquake condition of a concrete base was simulated. Within the framework of the study, the authors modified the values of such parameters, such as the anchor embedment depth, anchor steel strength, base concrete class, and base crack width. As a result of the experimental studies, the authors identified all possible failure mechanisms for versatile types of anchorages, including steel and concrete cone failures, anchor slippage at the interface with the base concrete (two types of failure mechanisms were identified), as well as the failure involving the slippage of the adhesive composition at the interface with the concrete of the anchor embedment area. The data obtained by the authors encompasses total displacements in the elastic and plastic phases of deformation, values of the bearing capacity for each type of anchorage, values of the bearing capacity reduction, and displacements following multi-cyclic loading compared to static loading. As a result of the research, the authors identified two types of patterns that anchorages follow approaching the limit state: elastic-brittle and elastoplastic mechanisms. The findings of the experimental research allowed the authors to determine the plasticity coefficients for the studied types of anchors and different failure mechanisms. The research findings can be used to justify seismic load reduction factors to be further used in the seismic design of anchorages.