Igor Romenskiy, Tamara Zagoruiko, Alexander Mushchanov
The main approaches to the appointment of spatial and stiffness characteristics of the MARCHI system roofs when regulating the parameters of its stress-strain state
Donbas National Academy of Civil Engineering and Architecture
Abstract. The article discusses the possibilities of covering rectangular large-span roofs with on-standard side ratio with the help of the MARCHI structural system. The basic information about the typification of the main structural members of the MARCHI for rods and joint-connectors are given. The approaches for regulating the basic parameters of the stress-strain state (SSS) of the designed system are offered. Their realization allows to use typical structural elements of the system to cover the non-standard spans. Analytical dependences for appointment of basic parameters (relative height of roof h/l, relative bump of roof f/l) are suggested and the basic dependances of changing SSS parameters of the being designed roof depending on the design parameter change are considered.
Keywords: large-span structural root, system of MARCHI, stress-strain state, typification, unification.
Yevgen Gorokhov, Volodymyr Vasylev, Andrey Alyokhin
Static tests of intermediate portal support of type PMG330-28 on the DNACEA ground
Donbas National Academy of Civil Engineering and Architecture
Abstract. The article presents the results of static tests of portal, single-circuit metal support PMG330-28 voltage 330 based on multifaceted bent legs (IGU) with flange sections and braces. Tests were carried out on ground tests of power lines and tower structures Donbas National Academy of Civil Engineering and Architecture (on the DNACEA Ground). Prop is made of PJSC «Avdiivka Structural Steel Plant», Avdeevka. The purpose of the tests was to determine the bearing capacity and deformability of the support in the main design modes and conformity assessment supports the requirements of the project developed by PJSC «Avdiivka Structural Steel Plant». The tests were carried out on a support 7 of loading schemes that allow to check that the work supports PMG330-28 under static loads.
Keywords: tower testing station, static testing, overhead powerline suppotrs, multifaceted bent poles, displacement, loading scheme, flange connection.
Volodymyr Mushchanov a, Helena Bartolo b, Iurii Priadko a
Stress-strain state of the joints in reliability computation of suspension rod roofs
a Donbas National Academy of Civil Engineering and Architecture, b Polytechnic Institute of Leiria
Abstract. Due to the lack of investigations of reliability estimating of suspension roofs in common with their joints, that lead to urgency of estimation of stressed-strained state and reliability of welded joints of roofs and creating recommendations concerning such structures on the basis of obtained data. Due to this the reliability of large-span suspension roofs was investigated and a novel fundamental approach is proposed for the determination of joints’ reliability in the design phase of suspension rod roofs. The supporting joints of rigid threads to the external and internal contour, intermediate joints of the top and lower chords of supporting threads, joints of vertical and horizontal links to the supporting thread of the roof were used as design data. To estimate the joints’ reliability the logic and probabilistic methods were used for this analysis conjointly with the methods based on mathematical statistics. The structural design of the reliability of suspension roof joints are mainly described by sequential schemes, including parallel connections of dependent elements, corresponding to multi-element connections. The correlation between the elements of structural schematic joint drawings, due to the generality of strength of the steel, allows to reduce the quantity of elements and increase the final reliability level of joints.
Keywords: suspension roof joints, rigid threads, reliability indices, stressed-strained state, logic and probabilistic methods.
Anton Tanasoglo, Igor Garanzha, Vyacheslav Glukhov
Dynamicity coefficient refinement for intermediate support Р110-6 under the action of the pulsation component of the wind load
Donbas National Academy of Civil Engineering and Architecture
Abstract. In the paper is defined a dynamic calculation of the steel i ntermediate overhead power transmission line support P110-6 (OHTL) 110 kV to action pulsation component of the wind load. The purpose of dynamic calculation of lattice overhead line supports to the wind influence is an analysis of steady-state oscillations foothold in wind flow. In this case, the characteristics of nodal displacements, internal forces and stresses are determined in finite elements (lattice and belts) separately from the effects of moderate and pulsation components of the wind load. The technique and results of the dynamic analysis of the equivalent stiffness rod are shown. Paid attention to the main problems that may arise during the transition from the spatial model of the support to the rod with equal strength section. Considering a number of issues related to clarifying the definition of the dynamicity coefficient. On the basis of the calculation and generalization of the results carried out a detailed comparison of the sections’ dynamicity coefficients for the intermediate support with dynamicity coefficients of the equivalent stiffness rod under the action of pulsation component of the wind load.
Keywords: overhead power transmission line, intermediate support, dynamicity coefficient, space model, equivalent stiffness rod.