75504 2712-8172 Magazine of Civil Engineering 3 87 2019 1-135
RAR RUS 3-17 Semnan University Kafi Mohammad Ali mkafi@semnan.ac.ir Semnan University Nik Hoosh Kianoosh K.NikHoosh.PHD@semnan.ac.ir The geometric shape effect of steel slit dampers in their behavior There are considered the issues of structural modification of heavy concrete with oligomer-polymer additives. It has been established that crystallization of the cement stone proceeds at macro- and micro-levels. Macro-pores are filled with products of crystallization of cement particles grafted on the surface of polyvinyl chloride (PVC) macromolecules. The migration of PVC macromolecules and oligomers of the waste of coke-chemical production (WCP) into defective zones is due to the occurrence of internal stresses during hardening and volumetric compression which causes the closure of macro- and micro-pores, as well as cracks and capillaries. Thus, for the complex of physical and mechanical properties, resistance to sulfate corrosion and frost resistance the studied concrete based on structurally modified concrete can be used for producing pile foundations arranged in conditions of highly saline soils. The presented results of experimental studies indicate sufficient corrosion resistance of the concrete under study. 10.18720/MCE.87.1 yield damper cyclic loading flexural behavior shear behavior dissipated energy https://engstroy.spbstu.ru/article/2019.87.1/ 01.pdf
RAR RUS 18-34 Kazakh Leading Academy of Engineering and Construction Bryantsev Aleksandr Bryancev8989@mail.ru “AstanaStroyKonsalting” LLP Absimetov Vladimir Absimetov47@mail.ru 56091980300 0000-0003-3850-424X Peter the Great St. Petersburg Polytechnic University Lalin Vladimir vllalin@yandex.ru
29 Politechnicheskaya St., St. Petersburg, 195251, Russia
 The effect of perforations on the deformability of welded beam with corrugated webs Perforating steel beams is inevitable in some cases such as setting the technical equipment, though it decreases the carrying capacity of the element. The lack of information about the nature of the work, the values of critical stresses, the stability of the corrugated webs of the beams weakened by the perforations necessitated relevant studies for which the perforations of different diameters and with various ways of reinforcement were formed in the webs of the beams. Hence, this research focuses on the behavioral condition of welded beams with corrugated triangular webs weakened by different sized perforations at different locations. The impacts of these perforations on the transverse load-carrying capacity of the element and the suitable ways for stiffening them were investigated. An analysis is made of the influence of the edging thickness, paired vertical stiffeners at different widths of the ring stiffener on behavior of models of beams with a corrugated web with perforations. The influence of the bending of the lip around the exterior circumferential edge of the stiffener ring on the bearing capacity of beams with a corrugated web weakened by perforations was analyzed. The most effective location of the perforations along the web height has been determined. 10.18720/MCE.87.2 beam with corrugated web web perforation; triangular shape of corrugations beam deflection finite element analysis ring stiffener https://engstroy.spbstu.ru/article/2019.87.2/ 02.pdf
RAR RUS 35-45 55490061300 Shenyang Jianzhu University Lu Zhengran luzhengranglovel@126.com 57209739736 Shenyang Jianzhu University Chao Guo guochaoglovel@126.com Bearing capacity of fastener steel tube full hall scaffolds In fastener steel tube full hall scaffolds (FSTFHSs), the upper load is transferred to the posts through the top horizontal tubes. Further, the posts and horizontal tubes are not always in the same plane owing to the eccentricity of the coupler connections. Moreover, building materials and construction machinery are usually eccentrically stacked atop the FSTFHSs. Therefore, the members in FSTFHSs are subject to eccentric axial loading. This paper reports a systematic experimental and analytical study on the bearing capacity of FSTFHSs with eccentric axial loads on the tubes. Five full-scale FSTFHS specimens were built and tested for failure to obtain the strength and failure modes of FSTFHSs whose members are subject to eccentric axial loads. Advanced nonlinear finite element analysis (FEA) was conducted on the specimen models to obtain the strength and failure modes of the FSTFHS under eccentric axial load of the member and to compare with the experimental results. Parametric studies were conducted based on the FEA results to investigate the influence of eccentric axial loads on the bearing capacity of FSTFHSs with different geometric properties. The experimental and analytical results show that eccentric axial loading negatively affects the FSTFHS bearing capacity and that the main failure mode of FSTFHS is the local instability of the posts in the heaped load areas, accompanied by the twisting of the entire structure and bending of the top horizontal tubes. 10.18720/MCE.87.3 fastener steel tube full hall scaffold eccentric axial load bearing capacity failure mode nonlinear finite element analysis https://engstroy.spbstu.ru/article/2019.87.3/ 03.pdf
RAR RUS 46-58 Tennessee Technological University Islam Shariful mislam46@students.tntech.edu Aggregate concrete factor (λ) for burnt clay brick aggregate concrete This research aims to evaluate the lightweight burnt clay brick aggregate concrete factor (λ) which is commonly used as coarse aggregate in Bangladesh as well as Asia regions. The pull-out tests were carried out on four different types of concrete cylinder specimens (100 mm by 200 mm) made with natural crushed stone and first class burnt clay brick aggregates to determine the aggregate concrete factor (λ) and bond strength. Three different rebar diameter of 8 mm, 10 mm, and 12 mm with two different embedded lengths of 100 mm and 200 mm were investigated. In addition, compressive and splitting tensile strength tests were also performed to calculate bond strength and then λ. The experimental results showed that bond strength of 10 mm diameter rebar is higher compared to other bar diameter for both aggregates and both embedded length of 100 and 200 mm. While the bond strength of 200 mm embedded length rebar is higher than the embedded length of 100 mm. From this research study, it has been found that the average λ equal to 0.88 for Bangladeshi burnt clay brick aggregate. However, based on the test results a new equation is proposed for the lightweight brick aggregate concrete factor (λ). 10.18720/MCE.87.4 aggregate rebar geometries pull-out test bond strength aggregate concrete factor https://engstroy.spbstu.ru/article/2019.87.4/ 04.pdf
RAR RUS 59-65 36769668900 0000-0002-7620-614X Northeast Forestry University Wang Hongguang wanghongguang@zoho.com
Xiangfang District, Harbin, China
 Northeast Forestry University He Yao 1436287817@qq.com
Xiangfang District, Harbin, China
 36775113900 Zhejiang Sci-Tech University Pan Yunfeng yfpan@zstu.edu.cn 55673712800 Northeast Forestry University Yu Guanglong 327248688@qq.com Mechanical properties of magnesium potassium phosphate cement Magnesium potassium phosphate cement (MKPC) is a kind of phosphate hydrate formed by super-burning magnesia, soluble phosphate, a retarder and water in a suitable ratio and neutralised by acid-base neutralisation. A new type of environmentally friendly cementitious material, MKPC has received increasing attention in the field of civil engineering, especially in the field of building structural repair and reinforcement engineering. In this paper, the preparation process and compressive strength of MKPC were studied, and the mechanism of the compressive strength of MKPC was revealed. The shear strength characteristics of MKPC and epoxy resin in the interface between glass fibre sheets and concrete were compared. The results showed that when the water-cement ratio was 0.12 and the composite retarder ratio was 8 %, the compressive strength of MKPC increased to a maximum of 81.4 MPa. The formed BO33- covered the surface of KMgPO4·6H2O and hindered the continuation of the reaction, which resulted in a slow increase in the early compressive strength. MKPC can well replace the epoxy resin in the field of reinforced concrete structure and can significantly improve the interface bonding performance between glass fibre sheets and concrete. 10.18720/MCE.87.5 magnesium potassium phosphate cement (MKPC) epoxy resin glass fibre sheet interface bonding performance of concrete https://engstroy.spbstu.ru/article/2019.87.5/ 05.pdf
RAR RUS 66-79 56091980300 0000-0003-3850-424X Peter the Great St. Petersburg Polytechnic University Lalin Vladimir vllalin@yandex.ru
29 Politechnicheskaya St., St. Petersburg, 195251, Russia
 56296687300 0000-0002-2299-3096 Peter the Great Saint Petersburg Polytechnic University Rybakov Vladimir fishermanoff@mail.ru
Polytechnicheskay, 29
 Peter the Great Saint Petersburg Polytechnic University Diakov Stanislav stass.f.dyakov@gmail.com
Polytechnicheskay, 29
 Peter the Great Saint Petersburg Polytechnic University Kudinov Vadim vadim.russia@hotmail.com
Polytechnicheskay, 29
 Peter the Great Saint Petersburg Polytechnic University Orlova Ekaterina ye-cat-erina@yandex.ru
Polytechnicheskay, 29
 The semi-shear theory of V.I. Slivker for the stability problems of thin-walled bars The theory of thin-walled bars is important because light steel thin-walled structures are widely used. Traditionally, in calculations two theories are used: theory for open-profile and closed profile bars. The calculations are difficult, because different finite elements are used for different bar types. In 2005 V.I. Slivker worked out a semi-shear theory, which is suitable for thin-walled bars of open sections and closed sections. Similarly, this article presents the research on finite element modeling for the stability problems of thin-walled bars using the same theory to the geometric stiffness matrix. It was shown that the FEM solution converges to the exact one as the number of the finite elements increases. The numeral solutions were compared to critical forces obtained by the classical Euler formula. It was found that using the cross-sections as the thin-walled ones can reduce the critical force, especially for the open cross-sections. 10.18720/MCE.87.6 stability geometric stiffness matrix thin-walled bar finite element method semi-shear theory https://engstroy.spbstu.ru/article/2019.87.6/ 06.pdf
RAR RUS 80-92 6602848417 0000-0002-0587-4722 National Research Moscow State Civil Engineering University Kantardgi Izmail kantardgi@yandex.ru 7004066045 0000-0001-7723-6052 Institute Environmental Radioactivity, Fukushima University Zheleznyak Mark zheleznyak.m@gmail.com National Research Moscow State Civil Engineering University Anshakov Alexander anshakov.aleks.xx@yandex.ru Numerical modeling of nonlinear hydrodynamics of the coastal areas The nearshore hydrodynamic fields are produced by the nonlinear interactions of the shoaling waves of different time scales and currents. To simulate the wind wave propagated to the coasts, wave generated nearshore currents, nonlinear-dispersive wave transformation and wave diffraction in interaction with coastal and port structure, sediment transport and coastal erosion, the chains of the models should be used. The objective of the paper is to provide an overview of the results of the application of the model chains for the assessment of the wave impacts on new port designed at the Ob lip, Kara Sea to demonstrate needs for further development of the nonlinear models for the coastal engineering applications. The open source models WaveWatch III and SWAN has been used to simulate wave statistics of the dedicated areas of the studied coastal areas in high resolution to calculate the statistical parameters of the extreme wave approaching coastal zone construction in accordance with coastal engineering standards. 10.18720/MCE.87.7 numerical modeling coastal engineering chain of models interactive model https://engstroy.spbstu.ru/article/2019.87.7/ 07.pdf
RAR RUS 93-102 57200287767 Siberian Federal University Koyankin Alexandr KoyankinAA@mail.ru 12795222600 Novosibirsk state University of architecture and construction Mitasov Valery mitassovv@mail.ru 55507596900 Siberian Federal University Deordiev Sergey SDeordiev@sfu-kras.ru The compatibility of deformation of the hollow-core slab with beams The features of deformation of the key joint of a hollow core slab with precast-monolithic (monolithic) beam of a frame constructive system, including the Saret series. Experimental studies have been performed and numerical research of the stress-strain state of the slab and beam precast monolithic frame joint are carried out. Based on the obtained data, a comparative analysis of the results of numerical studies with experimental research has been performed, which showed a satisfactory convergence of results. As a result of the conducted researches new data concerning design features of the joint of the hollow slab with the beam have been obtained. Conclusions are given about the bearing capacity, stiffness and crack resistance of the structural solution of the joint node. The “weak points” associated with the design and operation of the joint of the slab with the beam are indicated. Technical solutions have been proposed to address the identified shortcomings, such as installation of the upper reinforcement in the hollow plate in longitudinal and transverse directions or exclusion of the key rigid joint to improve the structural reliability of the building. 10.18720/MCE.87.8 building construction reinforced concrete structures precast-monolithic slab beam key joint bearing capacity stiffness crack resistance https://engstroy.spbstu.ru/article/2019.87.8/ 08.pdf
RAR RUS 103-122 36787104800 0000-0002-9440-0341 National Research Moscow State Civil Engineering University Kozlov Dmitry kozlovdv@mail.ru
26 Yaroslavskoye av., Moscow, 129337 Russia
 National Research Moscow State Civil Engineering University Ghebrehiwot Anghesom Alemngus bahghi2012@gmail.com Efficacy of digital elevation and Nash models in runoff forecast Digital elevation models (DEMs) are extensively used in hydrological modelling and deriving the geomorphological properties of catchments. Recently, hydrologists have shown interest in researching the effects of DEMs from different sources on simulated outputs. As part of these efforts, this study aimed at evaluating the effects of DEM and algorithm selection on geomorphologic instantaneous unit hydrographs (GIUH)-Nash model based direct surface runoff predictions from ungauged Debarwa river catchment in Eritrea. Four open-source DEMs and two quantum geographic information system (QGIS) algorithms (GRASS and SAGA) were applied and corresponding outputs were evaluated using five observed events. The two algorithms resulted in drainage networks of similar stream orders but different geomorphologic characteristics such as stream ratios. The subjective and objective goodness of fit results indicated that the performance of the model based on SAGA was unsatisfactory whereas that of GRASS algorithm-based GIUH-Nash model was acceptable for all the DEM-scenarios irrespective of their sources and resolutions.  The study concluded that DEM in the calculation of flow hydrographs for the conditions of the Debarwa catchment selection has little impact on the GIUH-Nash model based direct surface runoff predictions and can be used indiscriminately. But, great care should be taken while selecting stream network generating algorithms, especially for catchments whose outlets are located near the confluence of two major rivers. 10.18720/MCE.87.9 digital elevation model QGIS algorithm GIUH-Nash model direct surface runoff hydrograph catchment river network runoff forecast https://engstroy.spbstu.ru/article/2019.87.9/ 09.pdf
RAR RUS 123-135 57209308360 Tashkent Institute of Engineers of Irrigation and Mechanization of Agriculture Bazarov Dilshod dbazarov61@mail.ru
39, Kary-Niyazov str., Tashkent, Uzbekistan, 100000
 Tashkent Institute of Engineers of Irrigation and Mechanization of Agriculture Mavlyanova Dildora dildoramav@mail.ru
39, Kary-Niyazov str., Tashkent, Uzbekistan, 100000
 Numerical studies of long-wave processes in the reaches of hydrosystems and reservoirs The problem of development of mathematical models and computer programs for calculation and forecast of various long-wave processes occurring in the reaches of reservoirs and hydro-systems is considered. The basic method to solve the problem is a mathematical modeling based on differential equations for the channel flow – the Saint-Venant equations using numerical methods. Conventional methods in hydraulics, methods for building mathematical models based on the laws of hydromechanics and their numerical calculations are also used. A mathematical and a computer program to carry out forecast calculations of long-wave processes occurring in the reaches of hydro-systems and reservoirs have been developed. The reliability of the results obtained is confirmed by rigorous mathematical statement, the use of well-known and tested equations and methods of hydraulics, and by the agreement of the results obtained in the work with the data obtained by other authors and available in literature. 10.18720/MCE.87.10 long-wave processes breakthrough the Saint-Venant equations of motion mathematical modeling numerical method https://engstroy.spbstu.ru/article/2019.87.10/ 10.pdf