The article presents a method for determining the stress-strain state of pile foundations for metal supports of power transmission lines during technical examination of power grid facilities in the Far North. An example of calculation using the LIRA automatic software package is given. The most stressed sections of structures are determined. The prospect of using CAD during technical examination of power grid facilities is proved.
Keywords: building structures, metal structures, energy facilities, stress-strain state, technical expertise
The method of determining the stress-strain state of metal poles of power transmission lines during the technical examination of electric grid facilities is analyzed. An example of a calculation using the automatic LIRA software package is given. The most stressed sections of structures are determined. The calculated method confirms the hypothesis that the triangular cross-section of the traverse of the portal intermediate support of the 500 kV overhead line is more economical (more efficient) than a tetrahedral (classical) cross section.
Keywords: building structures, metal structures, energy facilities, stress-strain state, technical expertise
The article discusses proposals for improving the use of discharge-pulse technology in the construction of boron-injection piles and camouflage widenings of bored piles with diameters of more than 300 mm. The application of voltages on the electrode system of a pulse current generator from 10 to 50 kV and an electric capacity of about 300 UF is considered. It has been found that in the case of using a relatively low voltage on the electrodes and an increase in the electrical capacity of the capacitor bank, the duration of the shock wave pressure on the ground increases several times. This contributes to a more intensive penetration of the liquid hardening material into the intergranular space of the near-well soil massif. It is proposed to use solutions using slag-alkali binders as a hardening material in the formation of boron-injection piles. Such solutions have greater fluidity compared to cement solutions and, when hardened, form a stone with greater strength and density. The article presents data from experimental studies confirming the increased strength (R = 130 MPa) and frost resistance of a solution prepared on slag-alkali binders, as well as data on determining their corrosion resistance to various aggressive media contained in groundwater. The possibility of stable breakdown of the interelectrode gap in aqueous solutions of slag-alkali media of various consistencies has been established, optimal energy parameters of the discharge have been determined for maximum effect of fixing the soils of the foundations.
Keywords: foundations, drilling piles, discharge-pulse technology, slag-alkali binders