Pub Date : 2023-07-01DOI: 10.37538/2224-9494-2023-2(37)-116-124
B. Sokolov, V. A. Titaev, I. A. Cherny
Introduction. Development of urban public transport networks in Russian cities involves modernization and improvement of rail transport to increase its traveling comfort, carrying capacity and reliability. Tram transport is environmentally friendly and has a high passenger capacity. The combination as well as the intersection of rail and pneumatic transport in the urban environment is considered to be an urgent issue. In this regard, State Standard 19231 “Reinforced concrete slabs for tramway track pavements. Specifications” is needed to be revised and updated due to changes in the requirements for concrete and emergence of new classes of steel reinforcement.Aim. To update State Standard 19231 in order to bring products for tram infrastructure to the proper regulatory and technological parameters in compliance with current requirements.Materials and methods. The present study involves an analysis of existing regulatory documents in the field of reinforced concrete materials and products, as well as a bibliographical research of works and expert opinions.Results. Updating the standard resulted in the establishment of specifications that meet the current demand, both in terms of regulations and scientific research.Conclusions. The updated interstate State Standard 19231 will contribute to a higher quality design and production of reinforced concrete slabs for tramway pavements, which will surely enhance their reliability and durability.
{"title":"Update of the interstate standard “Reinforced concrete slabs for tramway track pavements”","authors":"B. Sokolov, V. A. Titaev, I. A. Cherny","doi":"10.37538/2224-9494-2023-2(37)-116-124","DOIUrl":"https://doi.org/10.37538/2224-9494-2023-2(37)-116-124","url":null,"abstract":"Introduction. Development of urban public transport networks in Russian cities involves modernization and improvement of rail transport to increase its traveling comfort, carrying capacity and reliability. Tram transport is environmentally friendly and has a high passenger capacity. The combination as well as the intersection of rail and pneumatic transport in the urban environment is considered to be an urgent issue. In this regard, State Standard 19231 “Reinforced concrete slabs for tramway track pavements. Specifications” is needed to be revised and updated due to changes in the requirements for concrete and emergence of new classes of steel reinforcement.Aim. To update State Standard 19231 in order to bring products for tram infrastructure to the proper regulatory and technological parameters in compliance with current requirements.Materials and methods. The present study involves an analysis of existing regulatory documents in the field of reinforced concrete materials and products, as well as a bibliographical research of works and expert opinions.Results. Updating the standard resulted in the establishment of specifications that meet the current demand, both in terms of regulations and scientific research.Conclusions. The updated interstate State Standard 19231 will contribute to a higher quality design and production of reinforced concrete slabs for tramway pavements, which will surely enhance their reliability and durability. ","PeriodicalId":169749,"journal":{"name":"Bulletin of Science and Research Center of Construction","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132522226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01DOI: 10.37538/2224-9494-2023-2(37)-107-115
Деформирование Кладки, ИЗ Крупноформатных Камней, V. I. Obozov
Introduction. The paper investigates the stress-strain state of masonry walls made of large ceramic stones with dry vertical tongue and groove joints.Aim: to study the distribution of vertical stresses in masonry of large ceramic stones with vertical tongue and groove joints not filled with mortar.Materials and methods. The study was performed on the model of the wall section. Numerical study of the stress state of the wall masonry at a concentrated load was carried out for masonry with chain bond. The wall fragment was modeled by solid finite elements.Results. It was found that under a concentrated load, the deformable zone has the form of a triangle with a vertex under load and expanding as it moves away from the load point. Based on the studies conducted, the authors of the paper have proposed an approximate method for determining compression stresses in masonry stones with chain bond. When the load is concentrated, the zone of distribution of compressive stresses in the masonry has the form of a triangle. The study established the characteristics of the distribution of compressive stresses in chain masonry of walls made of large stones with dry vertical joints at a concentrated load.Conclusions. The study shows that the existing methods of calculating solid masonry are not suitable for calculating masonry with dry vertical tongue and groove joints because the latter comprise a discrete-continual system.
{"title":"Deformation of large stones masonry.","authors":"Деформирование Кладки, ИЗ Крупноформатных Камней, V. I. Obozov","doi":"10.37538/2224-9494-2023-2(37)-107-115","DOIUrl":"https://doi.org/10.37538/2224-9494-2023-2(37)-107-115","url":null,"abstract":"Introduction. The paper investigates the stress-strain state of masonry walls made of large ceramic stones with dry vertical tongue and groove joints.Aim: to study the distribution of vertical stresses in masonry of large ceramic stones with vertical tongue and groove joints not filled with mortar.Materials and methods. The study was performed on the model of the wall section. Numerical study of the stress state of the wall masonry at a concentrated load was carried out for masonry with chain bond. The wall fragment was modeled by solid finite elements.Results. It was found that under a concentrated load, the deformable zone has the form of a triangle with a vertex under load and expanding as it moves away from the load point. Based on the studies conducted, the authors of the paper have proposed an approximate method for determining compression stresses in masonry stones with chain bond. When the load is concentrated, the zone of distribution of compressive stresses in the masonry has the form of a triangle. The study established the characteristics of the distribution of compressive stresses in chain masonry of walls made of large stones with dry vertical joints at a concentrated load.Conclusions. The study shows that the existing methods of calculating solid masonry are not suitable for calculating masonry with dry vertical tongue and groove joints because the latter comprise a discrete-continual system. ","PeriodicalId":169749,"journal":{"name":"Bulletin of Science and Research Center of Construction","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125208505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.37538/2224-9494-2023-1(36)-86-98
P. Arleninov, S. Krylov, P. S. Kalmakova, A. V. Donov
Introduction. At present, creep is the main parameter determined in the long-term loading tests of concrete samples. However, creep appears to be only one of the deformation properties of a concrete sample during operation under the action of long-term loading. Another important property involves stress relaxation. Moreover, in individual problems (temperature problems, force redistribution problems, etc.), stress relaxation plays a more important role than creep. The introduction of a new test procedure can improve the accuracy of the obtained results (in standard creep tests, concrete relaxation is determined only mathematically), which in turn will increase the accuracy of calculations.Aim. To develop a procedure for testing concrete samples with the determination of their stress relaxation.Materials and methods. The article describes a methodology for conducting an experiment to study the relaxation of concrete samples in compression and bending modes, as well as the parameters of test benches, samples and the principles of load transfer.Results. The main results of experimental studies are presented graphically. An analysis of the results obtained was carried out; the convenience of conducting tests was evaluated.Conclusion. The prospects of the proposed approach for testing concrete samples are demonstrated, and recommendations for amending GOST 24544 are prepared.
{"title":"Experimental studies of concrete relaxation in various modes","authors":"P. Arleninov, S. Krylov, P. S. Kalmakova, A. V. Donov","doi":"10.37538/2224-9494-2023-1(36)-86-98","DOIUrl":"https://doi.org/10.37538/2224-9494-2023-1(36)-86-98","url":null,"abstract":"Introduction. At present, creep is the main parameter determined in the long-term loading tests of concrete samples. However, creep appears to be only one of the deformation properties of a concrete sample during operation under the action of long-term loading. Another important property involves stress relaxation. Moreover, in individual problems (temperature problems, force redistribution problems, etc.), stress relaxation plays a more important role than creep. The introduction of a new test procedure can improve the accuracy of the obtained results (in standard creep tests, concrete relaxation is determined only mathematically), which in turn will increase the accuracy of calculations.Aim. To develop a procedure for testing concrete samples with the determination of their stress relaxation.Materials and methods. The article describes a methodology for conducting an experiment to study the relaxation of concrete samples in compression and bending modes, as well as the parameters of test benches, samples and the principles of load transfer.Results. The main results of experimental studies are presented graphically. An analysis of the results obtained was carried out; the convenience of conducting tests was evaluated.Conclusion. The prospects of the proposed approach for testing concrete samples are demonstrated, and recommendations for amending GOST 24544 are prepared.","PeriodicalId":169749,"journal":{"name":"Bulletin of Science and Research Center of Construction","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128501388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.37538/2224-9494-2023-1(36)-72-85
V. Sheinin, V. Kovalev, A. B. Patrikeev, M. Kholmyanskiy
Introduction. The procedure currently recommended for karst hazard assessment includes a comparison of the cavity dimensions at the top of the karst massif with a “critical” value, sufficient for a shift of the cylindrical volume in the soil stratum. The scheme of calculating the “critical” value, proposed 40 years ago, is widely used due to its proven efficiency. However, in some cases, this procedure leads to an incorrect assessment of sinkhole development conditions, i.e., to incorrect decisions about the parameters of anti-karst measures.Aim. To adjust the procedure for calculating the “critical dimensions”, depending on the stratum structure and soil characteristics, as well as the load from the foundation.Materials and methods. The calculation formulas, transformed for computer calculations, are corrected by the introduction of a variable stability factor, the refinement of the schemes for accounting the effect of a surface load on the forces, acting along the side surface of the “shifting” volume, as well as by accounting, under the fulfillment of conditions for the general stability of a soil cylinder, the possibility of destroying the lower soil bearing layer, which is modeled as the clamped plate, loaded according to two different schemes depending on the properties of overlying soils.Results. The results of comparative calculations performed using the Mathcad software package for “standard” conditions are analyzed, and conclusions about the significance of the proposed corrections are drawn.Conclusion. When determining critical dimensions, it is necessary to introduce the values of the stability coefficient for the “shifting” soil volume, which are standard for geotechnics. In the case of using slab foundations, recommended in “karst-hazardous” areas, the effect of a surface load on the soil shift should be taken into account only when determining horizontal stresses on the side surface. Moreover, accounting can be carried out according to simple, but sufficiently justified, schemes. When the possibility of the lower layer destruction is accounted, the formation of a sinkhole is predicted at a smaller cavity span as compared to the proposed procedures.
{"title":"On the issue of determining the dimensions of the rock massif cavity sufficient for the formation of a sinkhole in the overlying soil stratum","authors":"V. Sheinin, V. Kovalev, A. B. Patrikeev, M. Kholmyanskiy","doi":"10.37538/2224-9494-2023-1(36)-72-85","DOIUrl":"https://doi.org/10.37538/2224-9494-2023-1(36)-72-85","url":null,"abstract":"Introduction. The procedure currently recommended for karst hazard assessment includes a comparison of the cavity dimensions at the top of the karst massif with a “critical” value, sufficient for a shift of the cylindrical volume in the soil stratum. The scheme of calculating the “critical” value, proposed 40 years ago, is widely used due to its proven efficiency. However, in some cases, this procedure leads to an incorrect assessment of sinkhole development conditions, i.e., to incorrect decisions about the parameters of anti-karst measures.Aim. To adjust the procedure for calculating the “critical dimensions”, depending on the stratum structure and soil characteristics, as well as the load from the foundation.Materials and methods. The calculation formulas, transformed for computer calculations, are corrected by the introduction of a variable stability factor, the refinement of the schemes for accounting the effect of a surface load on the forces, acting along the side surface of the “shifting” volume, as well as by accounting, under the fulfillment of conditions for the general stability of a soil cylinder, the possibility of destroying the lower soil bearing layer, which is modeled as the clamped plate, loaded according to two different schemes depending on the properties of overlying soils.Results. The results of comparative calculations performed using the Mathcad software package for “standard” conditions are analyzed, and conclusions about the significance of the proposed corrections are drawn.Conclusion. When determining critical dimensions, it is necessary to introduce the values of the stability coefficient for the “shifting” soil volume, which are standard for geotechnics. In the case of using slab foundations, recommended in “karst-hazardous” areas, the effect of a surface load on the soil shift should be taken into account only when determining horizontal stresses on the side surface. Moreover, accounting can be carried out according to simple, but sufficiently justified, schemes. When the possibility of the lower layer destruction is accounted, the formation of a sinkhole is predicted at a smaller cavity span as compared to the proposed procedures.","PeriodicalId":169749,"journal":{"name":"Bulletin of Science and Research Center of Construction","volume":"20 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116779394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.37538/2224-9494-2023-1(36)-99-117
G. I. Tikhonov, V. P. Blazhko, I. Tikhonov, L. I. Kachanovskaya, S. Kasatkin
Introduction. In connection with the present volumes of electrification in central Russia, the need for the construction of new electric power transmission lines (EPTLs) has decreased considerably. At the same time, the natural degradation of EPTL supports in time, as well as the prospects for developing the vast expanses of the northern, Siberian and Far Eastern regions, caused by the reorientation of Russia’s economic relations from the West to the East, make it urgent to increase production volumes and technical and economic efficiency of using spun reinforced concrete poles for EPTL supports.Aim. Industrial implementation of spun reinforced concrete poles with the high-strength innovation profile reinforcement by replacing A800 rebars with four-row-profile Au1000P rebars.Materials and methods. The article provides data on the full-scale tests of spun reinforced concrete poles for EPTL supports according to the GOST 22687.1-85 “Centrifugal cylinder reinforced concrete posts for high-voltage transmission lines. Structure and dimensions” [1]. Three pole samples with a length of 26 m were prepared and tested. One sample consisted of prestressed A800 rebars according to GOST 22687.1-85, while the other two prototypes include the prestressed Au1000P rebars with the four-row profile. In the second sample, the reinforcement scheme (diameters and rebar quantity) repeats the standard option, increasing the bearing capacity of the pole. Having the same bearing capacity as the pole, manufactured according to the GOST, the third sample promoted for the reduction in the quantity of non-stressed rebars.Results. A new scheme for reinforcing the pole sample using Au1000P rebars was developed. The results of the sample testing are presented; a comparative evaluation of the pole strength and deformation characteristics is given; technical and economic indicators, as well as the recommendations regarding the reinforcement of the prestressed spun concrete poles with Au1000P rebars are provided.Conclusion. According to the results of the performed study, an economic effect was established due to a reduction in the quantity of non-stressed rebars by 28 %. Poles with Au1000P prestressed rebars have an increased corrosion resistance and durability due to the closing of cracks formed during the impact of short-term dynamic loads from wind gusts, wire breaks, etc. In terms of a recommendation, it is proposed to update the GOST 22687.1-85 in order to use new types of high-strength reinforcement rolled products and higher strength concrete.
{"title":"Studies of spun concrete poles for electric power transmission line supports reinforced with Au1000P rebars","authors":"G. I. Tikhonov, V. P. Blazhko, I. Tikhonov, L. I. Kachanovskaya, S. Kasatkin","doi":"10.37538/2224-9494-2023-1(36)-99-117","DOIUrl":"https://doi.org/10.37538/2224-9494-2023-1(36)-99-117","url":null,"abstract":"Introduction. In connection with the present volumes of electrification in central Russia, the need for the construction of new electric power transmission lines (EPTLs) has decreased considerably. At the same time, the natural degradation of EPTL supports in time, as well as the prospects for developing the vast expanses of the northern, Siberian and Far Eastern regions, caused by the reorientation of Russia’s economic relations from the West to the East, make it urgent to increase production volumes and technical and economic efficiency of using spun reinforced concrete poles for EPTL supports.Aim. Industrial implementation of spun reinforced concrete poles with the high-strength innovation profile reinforcement by replacing A800 rebars with four-row-profile Au1000P rebars.Materials and methods. The article provides data on the full-scale tests of spun reinforced concrete poles for EPTL supports according to the GOST 22687.1-85 “Centrifugal cylinder reinforced concrete posts for high-voltage transmission lines. Structure and dimensions” [1]. Three pole samples with a length of 26 m were prepared and tested. One sample consisted of prestressed A800 rebars according to GOST 22687.1-85, while the other two prototypes include the prestressed Au1000P rebars with the four-row profile. In the second sample, the reinforcement scheme (diameters and rebar quantity) repeats the standard option, increasing the bearing capacity of the pole. Having the same bearing capacity as the pole, manufactured according to the GOST, the third sample promoted for the reduction in the quantity of non-stressed rebars.Results. A new scheme for reinforcing the pole sample using Au1000P rebars was developed. The results of the sample testing are presented; a comparative evaluation of the pole strength and deformation characteristics is given; technical and economic indicators, as well as the recommendations regarding the reinforcement of the prestressed spun concrete poles with Au1000P rebars are provided.Conclusion. According to the results of the performed study, an economic effect was established due to a reduction in the quantity of non-stressed rebars by 28 %. Poles with Au1000P prestressed rebars have an increased corrosion resistance and durability due to the closing of cracks formed during the impact of short-term dynamic loads from wind gusts, wire breaks, etc. In terms of a recommendation, it is proposed to update the GOST 22687.1-85 in order to use new types of high-strength reinforcement rolled products and higher strength concrete.","PeriodicalId":169749,"journal":{"name":"Bulletin of Science and Research Center of Construction","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115843812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-29DOI: 10.37538/2224-9494-2023-1(36)-51-58
T. Mukhamediev, S. Zenin
Introduction. The acting version of the Code of Practice on the design of fiber-reinforced concrete structures with non-steel fibers SP 297.1325800.2017 “Fiber-reinforced concrete structures and precast products with non-steel fibers. Design rules” contain no instructions for the strength calculation of circular cross-sections with and without reinforcement under the action of bending moments and longitudinal forces. In addition, the current version provides no instructions for determining the subclass index of fiber-reinforced concrete with non-steel fibers using the residual axial tensile strength, as well as those for calculating the fire resistance of fiber-reinforced concrete structures. The absence of these provisions leads to significant difficulties in the design of individual structures made of fiber-reinforced concrete, which increases material and time expenditures.Aim. To improve the system of urban planning activities in terms of clarifying and supplementing the current regulatory documents for the design of fiber-reinforced concrete structures with non-steel fibers.Methods and materials. A draft of amendment No. 2 to SP 297.1325800.2017 was developed taking into account contemporary requirements, as well as the latest scientific research. In particular, the results of the research work concerning the fire resistance of structures made of fiber-reinforced concrete with non-steel fibers, performed by the Research Institute of Concrete and Reinforced Concrete (NIIZHB) named after A.A. Gvozdev in 2020, were taken into account. In addition, the experience of the authors and design organizations, gained during the practical application of this Code of Practice, was analyzed in order to clarify its provisions for the convenience of users.Results. The results of the work involve the draft of the amendment No. 2 to SP 297.1325800.2017, whose positions include new calculation techniques, as well as the refinements of existing calculation and construction methods. The developed amendment has passed public discussions, as well as the necessary expertise, and is being prepared for approval and enactment.Conclusion. Positions of amendment No. 2 to SP 297.1325800.2017 “Fiber-reinforced concrete structures and precast products with non-steel fibers. Design rules” can be used to develop reliable design solutions for these structures, including the achievement of a certain economic effect.
{"title":"New amendment to the Code of Practice on the design of fiber-reinforced concrete structures with non-steel fibers","authors":"T. Mukhamediev, S. Zenin","doi":"10.37538/2224-9494-2023-1(36)-51-58","DOIUrl":"https://doi.org/10.37538/2224-9494-2023-1(36)-51-58","url":null,"abstract":"Introduction. The acting version of the Code of Practice on the design of fiber-reinforced concrete structures with non-steel fibers SP 297.1325800.2017 “Fiber-reinforced concrete structures and precast products with non-steel fibers. Design rules” contain no instructions for the strength calculation of circular cross-sections with and without reinforcement under the action of bending moments and longitudinal forces. In addition, the current version provides no instructions for determining the subclass index of fiber-reinforced concrete with non-steel fibers using the residual axial tensile strength, as well as those for calculating the fire resistance of fiber-reinforced concrete structures. The absence of these provisions leads to significant difficulties in the design of individual structures made of fiber-reinforced concrete, which increases material and time expenditures.Aim. To improve the system of urban planning activities in terms of clarifying and supplementing the current regulatory documents for the design of fiber-reinforced concrete structures with non-steel fibers.Methods and materials. A draft of amendment No. 2 to SP 297.1325800.2017 was developed taking into account contemporary requirements, as well as the latest scientific research. In particular, the results of the research work concerning the fire resistance of structures made of fiber-reinforced concrete with non-steel fibers, performed by the Research Institute of Concrete and Reinforced Concrete (NIIZHB) named after A.A. Gvozdev in 2020, were taken into account. In addition, the experience of the authors and design organizations, gained during the practical application of this Code of Practice, was analyzed in order to clarify its provisions for the convenience of users.Results. The results of the work involve the draft of the amendment No. 2 to SP 297.1325800.2017, whose positions include new calculation techniques, as well as the refinements of existing calculation and construction methods. The developed amendment has passed public discussions, as well as the necessary expertise, and is being prepared for approval and enactment.Conclusion. Positions of amendment No. 2 to SP 297.1325800.2017 “Fiber-reinforced concrete structures and precast products with non-steel fibers. Design rules” can be used to develop reliable design solutions for these structures, including the achievement of a certain economic effect.","PeriodicalId":169749,"journal":{"name":"Bulletin of Science and Research Center of Construction","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114814678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-29DOI: 10.37538/2224-9494-2023-1(36)-7-26
Z. A. Aldrebi
Introduction. The historic cable-stayed suspension bridge of the city of Deir ez-Zor in Syria, which is an architectural monument, is described. The history of its creation at the beginning of the twentieth century and its destruction during the hostilities in 2013 is given. The importance of this bridge for the city and for the country as a whole is indicated, which was the reason for its choice as an object of research.Aim. The study is intended to contribute to the restoration and (or) subsequent seismic strengthening of the cable-stayed suspension bridge of Deir ez-Zor.Materials and methods. A detailed description and characteristics of the above-mentioned bridge, built according to the system of the French design engineer Albert Gisclard, according to the project of the design engineer Gaston Leinekugel Le Cocq and the construction company “Arnodin”, are given. Suspension and cable-stayed bridges are compared and distinctive features of Gisclard bridges are listed. Radial cablestayed trusses are described and the scheme of load distribution in suspension and cable-stayed bridges is illustrated. Examples of the calculation of the stay cables and their cross-sectional area are briefly given, which can be used in the restoration of the bridge and its cable stays. The method of protecting the bridge from wind and seismic influences is considered.Results. Lines of influence for radial cable trusses of the Gisclard system are illustrated, showing tension and compression zones in the cable stays. Stiffening cables are recommended for adding to the design of multi-span cable-stayed and suspension bridges, as they increase their rigidity. To protect the cable-stayed suspension bridge of the city of Deir ez-Zor from wind and seismic vibration, a method of damping or reducing wind and seismic vibration using magnetorheological liquid dampers with tuned mass is proposed.Conclusions. Conclusions are drawn about the feasibility of seismic strengthening of the Deir ez-Zor bridge together or after restoration with the help of the above-mentioned dampers, which allow protecting the bridge, while maintaining its authenticity and original exterior appearance.
介绍。介绍了叙利亚代尔祖尔市历史悠久的斜拉桥，这是一座建筑纪念碑。它在20世纪初创建的历史，并在2013年的敌对行动中被摧毁。本文指出了这座桥对城市和整个国家的重要性，这也是选择它作为研究对象的原因。本研究旨在为代尔祖尔斜拉桥的恢复和(或)后续抗震加固做出贡献。材料和方法。根据法国设计工程师Albert Gisclard的系统，根据设计工程师Gaston Leinekugel Le Cocq和建筑公司“Arnodin”的项目，对上述桥梁进行了详细的描述和特点。对悬索桥和斜拉桥进行了比较，并列举了Gisclard桥的特点。介绍了径向斜拉桥桁架结构，并对悬索桥和斜拉桥的荷载分配方案进行了说明。简要给出了斜拉索及其截面积的计算实例，可供桥梁及其斜拉索修复时参考。考虑了保护桥梁免受风和地震影响的方法。图中显示了Gisclard系统径向索桁架的影响线，显示了斜拉索的拉伸和压缩区域。建议在多跨斜拉桥和悬索桥的设计中加入加劲索，因为加劲索可以增加斜拉桥和悬索桥的刚度。为了保护代尔祖尔市斜拉桥免受风和地震的影响，提出了一种利用调谐质量磁流变液阻尼器阻尼或减小风和地震振动的方法。通过对代尔祖尔大桥进行抗震加固，在保持桥梁真实性和原有外观的同时，采用上述减震器对大桥进行抗震加固的可行性进行了分析。
{"title":"The first steps towards the restoration and seismic strengthening of the historic cable-stayed suspension bridge of Deir ez-Zor in Syria","authors":"Z. A. Aldrebi","doi":"10.37538/2224-9494-2023-1(36)-7-26","DOIUrl":"https://doi.org/10.37538/2224-9494-2023-1(36)-7-26","url":null,"abstract":"Introduction. The historic cable-stayed suspension bridge of the city of Deir ez-Zor in Syria, which is an architectural monument, is described. The history of its creation at the beginning of the twentieth century and its destruction during the hostilities in 2013 is given. The importance of this bridge for the city and for the country as a whole is indicated, which was the reason for its choice as an object of research.Aim. The study is intended to contribute to the restoration and (or) subsequent seismic strengthening of the cable-stayed suspension bridge of Deir ez-Zor.Materials and methods. A detailed description and characteristics of the above-mentioned bridge, built according to the system of the French design engineer Albert Gisclard, according to the project of the design engineer Gaston Leinekugel Le Cocq and the construction company “Arnodin”, are given. Suspension and cable-stayed bridges are compared and distinctive features of Gisclard bridges are listed. Radial cablestayed trusses are described and the scheme of load distribution in suspension and cable-stayed bridges is illustrated. Examples of the calculation of the stay cables and their cross-sectional area are briefly given, which can be used in the restoration of the bridge and its cable stays. The method of protecting the bridge from wind and seismic influences is considered.Results. Lines of influence for radial cable trusses of the Gisclard system are illustrated, showing tension and compression zones in the cable stays. Stiffening cables are recommended for adding to the design of multi-span cable-stayed and suspension bridges, as they increase their rigidity. To protect the cable-stayed suspension bridge of the city of Deir ez-Zor from wind and seismic vibration, a method of damping or reducing wind and seismic vibration using magnetorheological liquid dampers with tuned mass is proposed.Conclusions. Conclusions are drawn about the feasibility of seismic strengthening of the Deir ez-Zor bridge together or after restoration with the help of the above-mentioned dampers, which allow protecting the bridge, while maintaining its authenticity and original exterior appearance.","PeriodicalId":169749,"journal":{"name":"Bulletin of Science and Research Center of Construction","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128024299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-29DOI: 10.37538/2224-9494-2023-1(36)-41-50
Y. Krivtsov, I. R. Ladygina, Y. Groshev, M. A. Komarova, G. P. Eremina
Introduction. The article examines methods and means of monitoring the fire-retardant coatings of metal structures used in turbine halls of operating NPPs during the works on the assessment of the technical state, residual service life and service life extension of fire-retardant coatings. This appears to be an extremely urgent task, especially within the framework of the NPP pre-operation and service life extension. For operating NPPs, the re-surfacing of fire-retardant coatings due to the service life expiration can represent an insurmountable task.Aim. To establish current requirements for the content and sequence of works on the assessment of the technical state, residual life and service life extension of fire-retardant coatings applied to NPP turbine hall metal structures.Materials and methods. An analysis of existing methods and techniques for assessing the technical state, residual service life and service life extension of fire-retardant coatings applied to the turbine hall metal structures of operating NPPs was carried out.Results. The acknowledged methods and techniques for assessing the technical state, residual service life and service life extension of fire-retardant coatings are examined, their effectiveness is analyzed and promising trends on the establishment/forecast of the guaranteed service life are noted, including the development of promising fire-retardant compositions with an increased service life and the development of necessary programs-procedures for the establishment and substantiation of the guaranteed storage life of fire-retardant coatings, as well as the assessment of its extension.Conclusion. The requirements for the content and sequence of works on the assessment of the technical state, residual life and service life extension of fire-retardant coatings applied to NPP turbine hall metal structures are established.
{"title":"Assessment of the technical state, residual life and service life extension of fire-retardant coatings for NPP turbine hall metal structures","authors":"Y. Krivtsov, I. R. Ladygina, Y. Groshev, M. A. Komarova, G. P. Eremina","doi":"10.37538/2224-9494-2023-1(36)-41-50","DOIUrl":"https://doi.org/10.37538/2224-9494-2023-1(36)-41-50","url":null,"abstract":"Introduction. The article examines methods and means of monitoring the fire-retardant coatings of metal structures used in turbine halls of operating NPPs during the works on the assessment of the technical state, residual service life and service life extension of fire-retardant coatings. This appears to be an extremely urgent task, especially within the framework of the NPP pre-operation and service life extension. For operating NPPs, the re-surfacing of fire-retardant coatings due to the service life expiration can represent an insurmountable task.Aim. To establish current requirements for the content and sequence of works on the assessment of the technical state, residual life and service life extension of fire-retardant coatings applied to NPP turbine hall metal structures.Materials and methods. An analysis of existing methods and techniques for assessing the technical state, residual service life and service life extension of fire-retardant coatings applied to the turbine hall metal structures of operating NPPs was carried out.Results. The acknowledged methods and techniques for assessing the technical state, residual service life and service life extension of fire-retardant coatings are examined, their effectiveness is analyzed and promising trends on the establishment/forecast of the guaranteed service life are noted, including the development of promising fire-retardant compositions with an increased service life and the development of necessary programs-procedures for the establishment and substantiation of the guaranteed storage life of fire-retardant coatings, as well as the assessment of its extension.Conclusion. The requirements for the content and sequence of works on the assessment of the technical state, residual life and service life extension of fire-retardant coatings applied to NPP turbine hall metal structures are established.","PeriodicalId":169749,"journal":{"name":"Bulletin of Science and Research Center of Construction","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129733275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-29DOI: 10.37538/2224-9494-2023-1(36)-27-40
D. Zheldakov, O. Ponomarev, A. Minasyan, S. Tursukov
Introduction. According to the main legal acts of the Russian Federation that regulate the procedure of inspection and monitoring of buildings and structures, the technical statement should include the results obtained during the studies and calculations of possible temporal variations. However, these results are virtually absent in the monitoring technical documentation presented today. In the case of brickwork, this is primarily due to the lack of reliable methods for durability surveys. For example, the formation of salts in the brick material can affect its durability. Such reactions are considered as the side reactions of the second type, i.e., reactions caused by external effects.Aim. To develop an engineering technique for assessing the durability of a brick material on the basis of a mathematical model.Materials and methods. The article presents the results obtained in a survey of a free-standing brick building, as part of the “GES-2” Moscow multifunctional complex built in 1906, using the developed techniques. The process of brick material destruction is considered according to the laws of physical chemistry and described by a multi-stage process.Results. The developed technique for assessing the durability of building ceramics can be additionally used to assess the residual durability of a historical building brick material.Conclusion. During the durability assessment of building walls made of ceramic masonry materials, it is necessary to take into account not only the frost resistance, but also the chemical destruction of materials. It is proposed to supplement the masonry inspection technique outlined in GOST 31937-2011 with the following items: sampling rules for the subsequent determination of the moisture content in structural materials with a statement of the requirements for equipment; sampling rules for the subsequent determination of the material residual durability, including the technique for calculating residual durability.
{"title":"Durability assessment of brick and stone structures in engineering surveys","authors":"D. Zheldakov, O. Ponomarev, A. Minasyan, S. Tursukov","doi":"10.37538/2224-9494-2023-1(36)-27-40","DOIUrl":"https://doi.org/10.37538/2224-9494-2023-1(36)-27-40","url":null,"abstract":"Introduction. According to the main legal acts of the Russian Federation that regulate the procedure of inspection and monitoring of buildings and structures, the technical statement should include the results obtained during the studies and calculations of possible temporal variations. However, these results are virtually absent in the monitoring technical documentation presented today. In the case of brickwork, this is primarily due to the lack of reliable methods for durability surveys. For example, the formation of salts in the brick material can affect its durability. Such reactions are considered as the side reactions of the second type, i.e., reactions caused by external effects.Aim. To develop an engineering technique for assessing the durability of a brick material on the basis of a mathematical model.Materials and methods. The article presents the results obtained in a survey of a free-standing brick building, as part of the “GES-2” Moscow multifunctional complex built in 1906, using the developed techniques. The process of brick material destruction is considered according to the laws of physical chemistry and described by a multi-stage process.Results. The developed technique for assessing the durability of building ceramics can be additionally used to assess the residual durability of a historical building brick material.Conclusion. During the durability assessment of building walls made of ceramic masonry materials, it is necessary to take into account not only the frost resistance, but also the chemical destruction of materials. It is proposed to supplement the masonry inspection technique outlined in GOST 31937-2011 with the following items: sampling rules for the subsequent determination of the moisture content in structural materials with a statement of the requirements for equipment; sampling rules for the subsequent determination of the material residual durability, including the technique for calculating residual durability.","PeriodicalId":169749,"journal":{"name":"Bulletin of Science and Research Center of Construction","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116176431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-29DOI: 10.37538/2224-9494-2023-1(36)-59-71
A. Churkin
Introduction. An increase in the complexity of tasks arising from the quality control of geotechnical structures ultimately increases the role of indirect methods as part of the survey set. Low strain impact testing of piles length and integrity is currently one of the most common non-destructive geophysical methods used in the state diagnostics of foundations. The capabilities and limitations of the method are associated with the peculiarities of its basic theoretical model describing the propagation of elastic waves in a thin rod. In this regard, specialists often have recourse to the auxiliary techniques of field research.Aim. To inform test engineers, designers and employees of supervisory organizations about the potential of auxiliary methods for the low strain impact quality control of pile foundations.Methods and materials. The features of the theoretical model of the low strain impact pile quality control, as well as the associated capabilities and limitations of the method are described. The auxiliary methods of data collection and analysis were used for the survey of pile foundations, including those in the composition of existing structures.Results. The results of the work are represented by additional information obtained about the foundations surveyed using the auxiliary methods of data collection and analysis. An alternative arrangement of sensors relative to the surveyed structure was used for determining the depth of piles in the composition of grade beam footings and existing structures. The common shot point profiling (ultra-seismic method) was used to assess the velocity of rod wave propagation in the body of the structure. The options of data presentation in the parallel seismic method were used to demonstrate its potential for the quality control of foundation concrete.Conclusion. The auxiliary methods of data collection and analysis used in the low strain impact survey of pile foundations can significantly increase the reliability of conclusions about the depth and integrity of a structural material.
{"title":"Capabilities of auxiliary techniques for low strain impact testing of piles foundations","authors":"A. Churkin","doi":"10.37538/2224-9494-2023-1(36)-59-71","DOIUrl":"https://doi.org/10.37538/2224-9494-2023-1(36)-59-71","url":null,"abstract":"Introduction. An increase in the complexity of tasks arising from the quality control of geotechnical structures ultimately increases the role of indirect methods as part of the survey set. Low strain impact testing of piles length and integrity is currently one of the most common non-destructive geophysical methods used in the state diagnostics of foundations. The capabilities and limitations of the method are associated with the peculiarities of its basic theoretical model describing the propagation of elastic waves in a thin rod. In this regard, specialists often have recourse to the auxiliary techniques of field research.Aim. To inform test engineers, designers and employees of supervisory organizations about the potential of auxiliary methods for the low strain impact quality control of pile foundations.Methods and materials. The features of the theoretical model of the low strain impact pile quality control, as well as the associated capabilities and limitations of the method are described. The auxiliary methods of data collection and analysis were used for the survey of pile foundations, including those in the composition of existing structures.Results. The results of the work are represented by additional information obtained about the foundations surveyed using the auxiliary methods of data collection and analysis. An alternative arrangement of sensors relative to the surveyed structure was used for determining the depth of piles in the composition of grade beam footings and existing structures. The common shot point profiling (ultra-seismic method) was used to assess the velocity of rod wave propagation in the body of the structure. The options of data presentation in the parallel seismic method were used to demonstrate its potential for the quality control of foundation concrete.Conclusion. The auxiliary methods of data collection and analysis used in the low strain impact survey of pile foundations can significantly increase the reliability of conclusions about the depth and integrity of a structural material.","PeriodicalId":169749,"journal":{"name":"Bulletin of Science and Research Center of Construction","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116820563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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