All magnetic elements that form a closed orbit and focus the beam of charged particles in the accelerator are installed on special precise and stable supports – girders. Like any mechanical system, the girder has its natural frequencies, at which the vibrations coming to it are amplified. To ensure the stability of the charged particle beam, it is important to understand how mechanical vibrations are transmitted from the floor to the magnetic element, since even small perturbations can lead to a worsening in the parameters of the charged particle beam. The article presents the results of experimental seismometric measurements of the girders for magnetic elements of the booster Siberian Circular Photon Source “SKIF”. Their natural frequencies are determined.
The results of the analysis of experimental data on pseudotriaxial loading of full-size samples of black shale rocks of the Bazhenov Formation are presented. The experiments were carried out under conditions of uniaxial loading and at lateral compression pressures of 20 and 40 MPa. It is shown that in the considered load range, the deformation of the rock beyond the elastic limit proceeds in different modes: dilatancy and compaction. Despite the low porosity of the rock, the transition from dilatation to compaction occurs at a pressure not exceeding 34 MPa. Based on the analysis of the obtained data, the stages of deformation in the loading diagrams are distinguished and the parameters of the mathematical model with a combined limiting surface are determined, which describes the deformation process in dilatancy and compaction modes.
The article considers a unified approach to modeling logging probes with both galvanic and induction electric field sources. This approach is based on the properties of the functional spaces used in the finite element method and allows for a single software implementation for various logging methods. As an example of the use of the proposed approach, the logging process in an anisotropic medium with a slope of the main axes of anisotropy is considered.
The paper presents the results of velocity observations for current deformation in underground gallery, In wells and on earth surface. Different instruments were used: short-base quarts tiltmeters and laser extensometers, sensors of water level with meters base, and long-base sensors (spacy geodynamic instruments with kilometers bases). Coseismic deformation jumps obtained (up to 10–6) at Baikal and Altay regions. Annual velocities (at 5·10–8 level) were registered at Baikal and Altay.
In the urban conditions in Salekhard city, a complex of methods, including electrical resistivity tomography (ERT), ground penetrating radar (GPR), a seismic survey on refracted waves (REF), on surface waves (MASW) and the standing waves selection, was tested on solving geocryological problems and monitor the permafrost at the building base. As a model object, a residential building on a pile foundation, built according to the principle I and equipped with a continuous geothermal monitoring system, was chosen. It has been established that the ERT, REF, and MASW methods are ineffective in the conditions of a reinforced concrete pile foundation in a grillage and a concrete floor screed with a layer of loose bulk soil under it. The best result was shown by GPR at frequencies of 150 and 400 MHz and seismic exploration with the standing wave selection. A combination of these methods is recommended for determining the upper permafrost boundary under buildings, determining the actual piles-length, the quality of their fixing, assessing the water content of soils in the area around the piles, and establishing the residual building life.
The article presents the results of the interpretation of unique archival data of vertical electrical soundings obtained in the Selenga basin of the Baikal rift zone in the 50s of the last century by the detachment of the Baikal geophysical expedition of the PGO "Irkutskgeofizika", using modern computer technologies. The purpose of this work is to refine the geoelectric characteristics of the sections according to the measurement profiles, as well as the structure of such seismically active structures as the Delta and Fofanovsky faults, the Proval Bay, the Tvorogovo-Istok uplift using a 2–3D inversion program with visual data visualization.
The paper proposed an algorithm for solving the coefficient inverse problem for the Helmholtz equation, which uses the minimization of the functional in the spectral domain. As an example, the parameters of layer on a half-space was found by using of a given function and its derivative on a plain upper boundary in 2D case.
A seismogeological model of the junction zone of the Nepa-Botuoba anteclise and the Ygyattinskaya depression was built based on the results of a comprehensive interpretation of deep drilling and seismic data. The position and propagation of regional high-rank faults have been specified, and a model of tectonic faults of the study area has been constructed. All faults of the study area were divided into three classes: those that cut the entire sedimentary cover; developed in the lower part of the sedimentary section, fading in the Cambrian salt pack; complicating the upper post-salt complex of rocks. Criteria for identifying thinning zones were developed and were made use of to identify oil and gas perspective objects within the Talakh, Ulakhan and Kharystan productive horizons.
