Institute Giprostroymost

To evaluate the impact of long-term deformations caused by concrete creep and shrinkage on the stress-strain state of the rigid column-superstructure joint in a frame bridge. To verify the applicability of modern creep and shrinkage models for this type of structure. Methods: The numerical modelling was performed using the Finite Element Method (FEM) in the Midas Civil software. Nonlinear long-term eff of concrete creep and shrinkage, as well as prestress losses in the reinforcement, were considered. Results: It was established that concrete shrinkage exerts the most signifi infl on longitudinal deformations and on forces in the joints during the early service stage. Concrete creep partially compensates for the stresses induced by shrinkage. The most signifi changes in forces occur within the fi year of service; thereafter, the rate of change decreases substantially. The research results have confi the necessity of accurately accounting for long-term deformations in design. Practical signifi The presented results will enable a more accurate prediction of the rigid column-superstructure joint behavior in frame bridges, thereby reducing the risk of crack formation and elevated residual stresses. This will contribute to enhanced reliability and durability of bridge structures.

Purpose: to consider the problem of railway subgrade stability under seismic conditions. Show the need to increase stability during an earthquake. Determine the possibility of increasing seismic resistance by introducing a damping layer into the structure. Determine the optimal damping parameters, taking into account the rational use of subgrade materials. Methods: calculations of embankment stability are carried out using the method of G. M. Shakhunyants. An earthquake is taken into account through an increase in shear forces acting on the cells of the sliding massif. The maximum accelerations of the compartments are determined based on the results of finite element method dynamic calculation of a stress-strain state of the embankment during an earthquake, which is specified through an accelerogram. Results: the effectiveness of using a damping layer in the embankment structure, introduced to increase seismic resistance, has been shown. The dependence of the stability coefficient of the embankment on the Rayleigh parameters of the material composing the body of the entire embankment has been determined. For the best material parameters, the optimal thickness and position of the damping layer in the structure are determined, at which the stability coefficient takes on a standard value and the volume of the damping layer is minimal. Practical importance: as an alternative to the normative approach, the possibility of increasing the stability of a railway embankment under earthquake conditions by introducing a damping layer into the structure is presented. An algorithm for selecting optimal damping parameters has been determined in order to increase seismic resistance.

Wind loads lead to bridge oscillations. To verify aeroelastic stability of superstructures physical aerodynamic investigations are performed with vehicles taken into consideration. Usually oscillation amplitudes in this configuration are much bigger than without vehicles. At the same time, stiffness and damping of the vehicles are not modeled as that could decrease oscillation amplitudes. The main goal of this work is to determine vehicle influence on bridge superstructure damping. To solve the system of equations of motion from which vertical oscillations of vehicle – structure system were determined implicit Newmark method was implemented. Vehicle – structure system damping was assessed by logarithmic oscillations decrement, obtained from the results of free decay and forced resonance vibrations. Calculations were performed with different number of traffic lanes used by vehicles. Furthermore, suspension stiffness and damping also varied. As a result, it was obtained that for suspension with good damping characteristics vehicle – structure damping system was several times bigger than for superstructure without vehicles. With a satisfactory condition of the suspensions, the influence of vehicles can be estimated at 20 %. The obtained results can allow increasing the decrement of superstructure model in physical aerodynamic investigations with consideration of vehicles. However, it is necessary to carry out some research on determination of most frequently used vehicles’ suspensions.

В статье охарактеризована пространственная организация инновационной деятельности в городах России и её столице, отмечены быстрое развитие цифровых технологий, способ­ствующее вхождению России в число стран - инноваторов рейтинга Bloomberg-2018, возможности использования потенциала, накопленного в сфере исследований и разра­боток, для совершенствования производства, образования, строительства, здравоохранения и коммунального хозяйства. Инновационная деятельность в России становится инструмен­том совершенствования градостроительной среды, однако в производстве инноваций федеральные округа и входящие в них города участвуют с разной активностью.
 В Центральном округе сосредоточивается более половины занятых исследованиями и разработками, а в Москве - чуть менее трети. В столице организуется единый инновационный кластер (ИК), включающий учреждения Российской академии наук, Московский государственный университет, технические вузы, технопарки, ИТ - компании, бизнес-инкубаторы и другие связанные с ними объекты. Идет процесс создания высокотех­нологичных предприятий, производительность труда превыша­ет средние показатели по стране в 2,5 раза. В конструкторском бюро Российской самолетостроительной компании МиГ (РСК «МиГ») разрабатываются прогрессивные технологии, создают­ся новые и совершенствуются существующие виды продукции. Инноград «Сколково» готовит магистров и аспирантов для работы в области информационных технологий, энергетики, биомедицины и космической медицины.
 Московский опыт распространяется на удалённые регионы России, включая кризисные города (например, Новокузнецк и Тольятти). В статье намечены пути оживления кризисных городов Европейской и Азиатской частей страны и ставится задача создания модели эффективного градопреобразования с использованием инструментов инновационной деятельности.

The article deals with some interesting engineering solutions implemented in the process of installation of arch span structures of the channel part of the bridge crossing the Volga river in Nizhny Novgorod, due to the design features of the arch span structures and local conditions: technology of assembling arches on the coastal slipway; construction of the slipway for Assembly and tightening of the arch trusses of the arch; technology lateral shifting of the arches on the piers on carriage; design piers of the carriages and pusher device; technology of loading and transportation of arches on floating supports; design of floating supports, their adjustment, strengthening of used barges; snap-in for positioning floating supports; erection strengthening arched spans with temporary stands and pendants; technology of lifting and installation of arches in the design position; used equipment and floating means; a way of immersing the tubular piles piers and methods to confirm their load-carrying ability; necessary coordination with regulatory organizations. The engineering novelty of the above technical solutions in the method of installation of arched superstructures with flexible tightening and cable-stayed suspensions – a design that was not initially adapted to surfacing installation. The author presents drawings and photographs of the most typical auxiliary structures and technological processes that took place during the construction of arch span structures of the bridge. This material can serve as an analogue in the design and construction of such out-of-class bridges across large navigable rivers.

The issues of a numerical modelling magnetic field topology in the front part of the microtunneling shield with regard to massive ferromagnetic objects in its structure, such as rotor, main drive shaft, blade-bed plate, bed plates and hydraulic cylinder block, were considered. Based on the investigation results, the authors established a possible use of ferroprobe sensors to monitor the parameters of the magnetic field formed by underground power utilities, the requirements to the parameters of ferroprobe magnetic sensors were determined, and their arrangement in the shield was defined. The influence of the ferroprobe arrangement in the microtunneling shield housing being a massive ferromagnetic object was established and investigated. The measures to eliminate accidental feedback between the ferroprobe windings arising during its operation in the shield housing were offered. The possibility to arrange the magnetic sensors in the microtunneling shield housing for realization of a magnetometric part of the advanced exploration system was experimentally confirmed.

В статье на основе анализа исследований исторической городской среды формируется перечень качеств, определяющих идентичность исторического поселения. Описываются качества идентичности поселка Билимбай, одного из исторических горнозаводских поселений Урала. Выявлены тенденции развития городов-заводов Урала и факторы, угрожающие сохранению исторической идентичности. Работа выполнена по плану ФНИ на 2019 г. при поддержке РААСН и Минстроя России в соответствии с Государственной программой Российской Федерации «Развитие науки и технологий» на 2013-2020 гг., Программой фундаментальных научных исследований государственных академий наук на 2013-2020 гг. The article forms a list of qualities that are necessary to determine the identity of a historical settlement. The list is based on the analysis of studies of the historical urban environment. Describes the qualities of the identity of the Bilimbay, one of the historical mining and metallurgical settlements of the Urals. The development trends of the Urals city-plants and the factors entailing a threat to the preservation of historical identity are identified.

Modern buildings and structures are, most often, complex multi-element systems created in order to implement a lot of various functions. During their life cycle a great deal of operation states take place. The specificity of structural engineering is such that its final product (a structure or a building) should meet three, often contradictory, requirements: functionality, aesthetics and designability.