Magazine of Civil Engineering

RAR RUS 3-22 Peter the Great Saint Petersburg Polytechnic University Levandovskiy Andrey levandovan@corning.com

Polytechnicheskay, 29

6701751705 0000-0002-7889-1996 Peter the Great Saint Petersburg Polytechnic University Boris Melnikov kafedra@ksm.spbstu.ru

Polytechnicheskay, 29

Corning SNG OOO Shamkin Artemiy shamkinaa@corning.com Modeling of porous material fracture Wide use of various porous materials in construction engineering applications requires development of up to date methods of non-destructive characterization and optimization of such materials. This work explores an approach to modeling of fracture of a brittle porous material. Available 3D digital data on the specimen geometry is converted into uniform finite element mesh consisting purely of elements of cubic shape. Fracture model is based on a series of linear solutions. Thus approach to linear modeling described in the previous papers could be utilized. Fracture is modeled by consecutive element erosion. A special element erosion criterion is established to avoid finite element size dependency. Two speed-up algorithms are proposed and tested. The approach described can be used for modeling fracture of uniform construction materials, also materials with inclusions under various mechanical and thermal loads. 10.18720/MCE.69.1 porous material fracture tomography element deletion element erosion element size fracture criterion finite element cordierite cubic elements https://engstroy.spbstu.ru/article/2017.69.1/

RAR RUS 23-33 Design and consulting firm "Strojrekonstrukcija" OOO Rasha Iosif oslik1939@rambler.ru Peter the Great Saint Petersburg Polytechnic University Pertseva Olga olya_perceva@mail.ru

Polytechnicheskay, 29

Peter the Great Saint Petersburg Polytechnic University Lazareva Alena lazareva101@mail.ru

Polytechnicheskay, 29

Peter the Great St. Petersburg Polytechnic University Martynov Gleb martynovgleb@rambler.ru

29 Politechnicheskaya St., St. Petersburg, 195251, Russia

Computational modelling of random distribution of stresses for wooden structures Stochastic allocation is the main characteristic of processes which can be described in wooden structures. Random distribution of stresses and deformations in such structures is mostly based on timber imperfections, such as different curvature of sticks, presence of knots, twigs and gnarls. Due to restoration works using of test methods and experiments in wooden structures, especially in architectural monuments, is limited because of high labor contribution and restrictions for protection of historic cultural heritage. Therefore, for decreasing efforts application of statistical methods with help of software tools is necessary and highly important in case of restoration of wooden structures. In particular, this article describes solution of design problem in choosing the optimal step of wall dowels with help of Monte Carlo method by the time of restoration in the Church of the Transfiguration on Kizhi Island. For analysis of stresses in cribbed panel wall an analytical model, which describes structural behavior sticks and dowels according to all imperfections, with three different dowels steps (0.67 m, 1.0 m and 1.67 m) was created in SCAD software. Stick curvature has been changed longitudinal direction and after that calculation of stresses was performed. As the result the most optimal dowel step is one meter, such as it produces minimal stresses due to the minimum intervention in the structure. 10.18720/MCE.69.2 restoration wooden structures Monte Carlo simulation timber probabilistic analysis https://engstroy.spbstu.ru/article/2017.69.2/

RAR RUS 34-43 Emperor Alexander I St. Petersburg State Transport University Titova Tamila t.s.ttitova@gmail.com Università degli Studi di Salerno Longobardi Antonia alongobardi@unisa.it Petersburg State Transport University Akhtyamov Rasul ahtamov_zchs@mail.ru Petersburg State Transport University E.S. Nasyrova ElinaSagitovna@yandex.ru Lifetime of earth dams The level of safety of small earth dams, operating without staff and measurement and control equipment, are considered in this study. Approach enabling the possibility to define the finite lifetime (Tf) of a small earth dam here presented. The proposed approach does not require any variables monitoring. It is based on the definition of Tf by assessing the water impact on the small earth dams by quantitative methods of system analysis. To assess the earth dam Tf, two approaches are offered, which based on the digraph method. They are the classification scale construction and the cluster method. On a quantitative base the Tf of small dam on urban area can be defined as the minimum between the two (75 year for the classification scale and 80 for the clustering), which is however well above the Russian regulations, which indicate a period of 50 years (design life). The estimated value allows defining robustness of earth dam and can be used as a criterion for safety management of earth dams, defining the needs to undertake actions to improve, during the life cycle, earth dam structural features. 10.18720/MCE.69.3 construction hydraulic engineering dam life-cycle https://engstroy.spbstu.ru/article/2017.69.3/

RAR RUS 44-55 6506150284 0000-0003-1139-3164 Moscow State University of Civil Engineering (National Research University) Sainov Mikhail mp_sainov@mail.ru

Moscow, Russia

National Research Moscow State University of Civil Engineering Kotov Filipp filipp_net@mail.ru Stress-strain state and performance of a high rockfill dam with a grout curtain This paper examines the results of numerical simulation of the stress-strain state (SSS) in a rockfill dam 235 m tall, with a massive three-tier grout curtain used as the impervious element. Calculations were done for multiple scenarios that reflected the wide range of possible changes of the modulus of deformation for the filler rock and cemented soil (200 MPa to 5000 MPa). The author’s original computation program was used in order to consider the elastoplastic behavior of soil. It was discovered that a super-tall dam with a vertical rigid impervious element features an adverse SSS: the hydrostatic pressure in the head reach gives creates a sliding wedge in the upper retaining prism. As the dam has rigid structure, this causes marginal state zones in the filler rock. Only when deforming ability of the filler rock is very low (deformation modulus above 300 MPa), the dam’s SSS may be acceptable. Strength characteristics of the grout curtain were evaluated based on stresses that emerge after it is created. The SSS of the grout curtain is mainly described by bending strains. In case of low deforming ability of the screen material, this can give rise to fissures in the screen material where it contacts the bedrock base. Strength and water impermeability of the grout curtain are secured only after bentonitecement slurry is injected to make the deforming ability of the screen material and filler rock comparable. 10.18720/MCE.69.4 cementing grout curtain rockfill dam cemented soil deformation modulus stress-strain state https://engstroy.spbstu.ru/article/2017.69.4/

RAR RUS 56-63 Peter the Great Saint Petersburg Polytechnic University Korotchenko Ivan saenko84@yandex.ru

Polytechnicheskay, 29

Peter the Great Saint Petersburg Polytechnic University Ivanov Ernest ivanov-efimov.e@yandex.ru

Polytechnicheskay, 29

Peter the Great Saint Petersburg Polytechnic University Manovitsky Sergey sergeimanovitsky@mail.ru

Polytechnicheskay, 29

Peter the Great Saint Petersburg Polytechnic University Borisova Victoria vi4ko93@mail.ru

Polytechnicheskay, 29

Peter the Great St. Petersburg Polytechnic University Semenov Kirill kvsemenov@bk.ru

29 Politechnicheskaya St., St. Petersburg, 195251, Russia

7801686579 0000-0001-7011-8213 Peter the Great Saint Petersburg Polytechnic University Barabanschikov Yuri ugb@mail.ru

Polytechnicheskay, 29

Deformation of concrete creep in the thermal stress state calculation of massive concrete and reinforced concrete structures In the article the thermal stress state of the reinforced concrete foundation of a nuclear power plant during the building period are analyzed. The calculation results of thermal stressed state in massive foundation slabs with and without concrete creep is given. The article also provides a comparative selection of insulation to ensure crack resistance of the foundation plate with and without creep. Authors found that calculation of the problem at elastic definition leads to substantial over the tensile stresses and the elongation deformations on the surface of the slab for the point of time to create maximum of heat dissipation. Not taking into account concrete creep deformation in the problems of crack control for concrete and reinforced concrete massive structures in the building period leads to substantial increasing of required thickness of heat insulation. 10.18720/MCE.69.5 massive concrete structures reinforced concrete cement setting temperature thermal stressed state thermal cracking resistance https://engstroy.spbstu.ru/article/2017.69.5/

RAR RUS 64-76 57194431559 0000-0003-4992-2084 Peter the Great Saint Petersburg Polytechnic University Galyamichev Alexander galyamichev@yandex.ru

Polytechnicheskay, 29

Peter the Great St. Petersburg Polytechnic University Alhimenko Аleksandr vils@cef.spbstu.ru

29 Politechnicheskaya St., St. Petersburg, 195251, Russia

Design features of facade cassettes from thin ceramics Thin ceramic plates are a promising material for architectural use which has significant potential for the realization of different interior and exterior solutions. The use of thin ceramics as facade cladding requires increased attention to the stress-strain state and the nature of its destruction. The main feature of this construction type is the ability to use facade panels with dimensions reaching 3000 x 1000 mm with a small weight and small thickness (3–5 mm). This research studies stress-strain state parameters of thin ceramic panels by testing on uniformly distributed load, simulating the wind effect on the cassette in conditions of the facade exploitation. As a result of laboratory tests obtained the dependence of the plate deflection on the action of a uniformly distributed load and identified convergence with the results of similar experimental work and theoretical studies. Also in this research was studied the work of facade structural sealants as part of facade structures: evaluated the effect of profile color, reinforcing mesh of plate and preliminary surface preparation with a primer on the adhesion to the cassette elements. 10.18720/MCE.69.6 facade structures cassette cladding thin ceramics adhesive-sealant connection aluminum structures ventilated facade https://engstroy.spbstu.ru/article/2017.69.6/

RAR RUS 77-88 Scientific-technical center "Etalon" Sharmanov Vladimir sharmanov_v@mail.ru Peter the Great Saint Petersburg Polytechnic University Simankina Tat'yana talesim@mail.ru

Polytechnicheskay, 29

Peter the Great Saint Petersburg Polytechnic University Mamaev Anton mamaev7@gmail.com

Polytechnicheskay, 29

BIM in the assessment of labor protection The article presents methodology of monitoring and control of safety and labor protection on the basis of modern innovative technologies and the digital model of the construction site. Monitoring based on the BIM technology enables a qualitatively new approach to monitoring safety and occupational safety on the construction site. The result of control by the offered method in the form of a security index, reflects the actual situation in the checked object and gives the chance to estimate influence of dangerous production factors. This approach to assessment will allow reacting quickly to the processes taking place in the territory of the checked object and also to prevent emergence of a dangerous situation. 10.18720/MCE.69.7 BIM 3D-model construction production building information modeling security index barometer security plugin occupational safety insurance https://engstroy.spbstu.ru/article/2017.69.7/