Effects on structures of the Managua earthquake of December 23, 1972

1974 ◽  
Vol 64 (4) ◽  
pp. 1069-1133
Author(s):  
Loring A. Wyllie ◽  
Richard N. Wright ◽  
Mete A. Sozen ◽  
Henry J. Degenkolb ◽  
Karl V. Steinbrugge ◽  
...  

Abstract The December 23, 1972, earthquake in Managua, Nicaragua caused extensive damage to structures throughout the city of Managua. There was damage to virtually every building in Managua, a city of approximately 400,000 inhabitants. An estimated 10,000 people were killed, mostly in the collapse of homes built of native taquezal construction. The city contained numerous reinforced concrete structures designed to recent standards. Although many of these buildings were heavily damaged, with some collapses, some had only minor damage. There were also several structures of structural steel. The paper provides an overview of structural effects and discusses the performance of selected buildings in Managua illustrating the range of performance of modern construction. Damage to numerous other buildings will be discussed. The paper, while emphasizing the structural effects on buildings, also discusses the performance of non-structural elements, mechanical equipment, etc.

2021 ◽  
Vol 9 (1) ◽  
pp. 1-5
Author(s):  
Irina Mayackaya ◽  
Batyr Yazyev ◽  
Anastasia Fedchenko ◽  
Denis Demchenko

Reinforced concrete elements of structures in the form of columns, beams, ceilings are widely used in the construction of buildings and structures of industrial and civil construction. In most cases, the columns serve as supports for other building elements, for example, crossbars, slabs, girders, beams. One of the cycles of the work of reinforced concrete structures is the state of their repair and reconstruction, including the stages of strengthening the elements. There is a problem of strengthening of reinforced concrete columns. The article deals with the issue of reinforcing columns and other structural elements having a cylindrical surface, with polymeric composite materials in the form of carbon fiber lamellae. The use of composite materials allows to increase the service life and strength of reinforced concrete structures used in construction.


Author(s):  
J. P. Hollings

This paper is reproduced from the proceedings of a
seminar on "Seismic Problems in Structural Engineering" arranged by the Departments of Civil Engineering and Extension Studies of the University of Canterbury, and held in Christchurch from May 13 to 16, 1968. Reinforced concrete, as customarily designed and detailed, and in contrast to structural steel, is essentially a brittle construction material. Brittleness can be a danger 
in regions prone to earthquakes. However, with due care in design and detailing, reinforced concrete structures can be made adequately ductile for good performance in earthquakes. This paper presents a rational design procedure to achieve ductility of reinforced concrete structures.


2020 ◽  
Vol 6 (159) ◽  
pp. 113-117
Author(s):  
O. Chuprynin ◽  
N. Sereda ◽  
A. Garbuz

One of the main tasks, which is solved at the design stage of the reinforced concrete element, is the analysis of the stress-strain state, as well as the determination of the service life. The article is devoted to modeling of nonlinear creep of reinforced concrete structural elements taking into account damages and return of the creep. The high priority of the research topic is substantiated, the purpose and objectives are formulated. A combination of a plastic model with fracture mechanics is proposed to simulate the behavior of concrete in accordance with its characteristics, including not only stress and deformation, but also the degradation of its stiffness. The resulting equations of state correspond to the law reverse deformations. The finite element method is used to solve the boundary value problem. For the sake of numerical modeling of thin-walled structures, the use of special shell elements is proposed. The mathematical formulation of the problem of creep of reinforced concrete structural elements taking into account anisotropy of material properties and creep deformations and return of the creep is presented. Creep problems of thin-walled structural elements were solved with the help of developed software. Analyzed the deformation of reinforced concrete panel of cylinder. The analysis of the results allows us to judge the effectiveness of the proposed model as a whole. The equation of state reflects the anisotropy of the material properties and takes into account the damage, which allows for a reliable assessment of the strength, stiffness and durability of reinforced concrete structures. Conclusions about the adequacy of the analysis of reliability and durability of reinforced concrete structures using the proposed model.


2013 ◽  
Vol 3 (4) ◽  
pp. 62-67
Author(s):  
N. A IL'IN ◽  
A. A PIShchULEV ◽  
P. N SLAVKIN ◽  
A. P ShEPELEV ◽  
R. R IBATULLIN

The article describes the main provisions: a method for assessing the severity of thermal damage of compressed reinforced concrete structural elements; methods of reducing residual tensile thermal stresses in compressed working armature element; recommendations for restoring lost in fire performance of compressed elements of reinforced concrete structures of buildings and installations.


Author(s):  
Oleg Kabantsev ◽  
Karomatullo Umarov

The article provides the results of studies the process of formation and development of plastic deformations in reinforced concrete structures with shear-wall under earthquake excitations. The studies are carried out by numerical methods using nonlinear dynamic analysis. The results of the research shown: that in the shear-wall elements of reinforced concrete structures the level of plastic deformations should be significantly reduced in relation to the normative level of plastics in other structural elements of the carrier system. The completed studies substantiated the introduction of differentiated values seismic-force-reduction factor for different types of structural elements on shear-walls reinforced concrete structures of earthquake-resistant buildings.


2018 ◽  
Vol 251 ◽  
pp. 02040
Author(s):  
Anna Malakhova

The article describes the process and causes of cracking of bearing reinforced concrete structures, revealed during the inspection of the technical condition of structural elements of buildings at the stage of their erection, at the stage of suspended construction and in the operational stage. The reasons for the appearance of cracks in reinforced concrete structures under force loads and climatic influences are analyzed. Possible reasons for the appearance of cracks in a monolithic reinforced concrete beam ceiling of a multi-storey building of a column structural system and in monolithic walls of an underground cylindrical reservoir, identified by the author of the article when inspecting the technical condition of these structures, are given. The relationship between the appearance of destructive cracks and the design errors of a monolithic reinforced concrete beam ceiling is shown. The complex nature of the causes of the appearance of cracks in the monolithic walls of the underground reservoir is revealed. The article describes the capabilities of the LIRA-CAD software package for determining the pattern and parameters of fracture-formation of reinforced concrete structures for subsequent comparison with the results of an inspection of the technical condition of structural elements of buildings and structures.


Author(s):  
В.В. Бондарь

Жизненный цикл строительного объекта включает не только проектирование, но и возведение, сопутствующее изготовление элементов конструкций, ввод в эксплуатацию и непосредственно эксплуатацию введенного здания или сооружения. Поэтому надежность того или иного здания или сооружения должна обеспечиваться совокупным выполнением требований действующих технических нормативно-правовых актов и стандартов на всех вышеперечисленных стадиях жизненного цикла. Тем не менее контролируемые параметры качества конструктивных элементов при монтаже могут значительно отличаться в нормативных документах и стандартах разных стран мира. Данный факт в еще большей степени препятствует интернационализации нормативных требований при строительстве зданий и сооружений, а также в определенных случаях может серьезно усложнить процесс достижения проектных показателей надежности здания или сооружения. В статье представлен обзор действующей в Республике Беларусь системы технических нормативных правовых актов в области проектирования и возведения железобетонных конструкций зданий и сооружений. Приведены основные проблемы, связанные с двойственностью существующей системы ТНПА. В публикации приведен сравнительный анализ контролируемых показателей качества (величин допустимых отклонений), представленных в действующих нормативных документах и стандартах Республики Беларусь и других ведущих стран мира, при возведении железобетонных элементов зданий и сооружений. На основе анализа контролируемых показателей качества сформулированы основные выводы, которые указывают на необходимость совершенствования системы национальных нормативных документов в области возведения железобетонных конструкций зданий и сооружений, а также на проблемы, которые могут возникать при одновременном действии в стране нескольких систем нормативной документации, в ряде случаев не согласующихся друг с другом. The life cycle of a construction project includes not only design, but also erection, concomitant manufacture of structural elements, commissioning and direct operation of the commissioned building or structure. Therefore, the reliability of a building or structure should be ensured by the combined fulfillment of the requirements of the existing technical normative legal acts and standards at all of the above stages of the life cycle. Nevertheless, the monitored controlled quality indexes of structural elements and their geometric configuration during installation can significantly differ in regulatory documents and standards around the world. This fact further impedes the internationalization of regulatory requirements in the construction of building and structures, and in certain cases can seriously complicate the process of achieving design indicators of the reliability of a building, or structure. The article provides an overview of the current system of technical regulatory legal acts in the field of design and execution of reinforced concrete structures of buildings and constructions. The main problems associated with the duality of the existing TRLA system, as well as with relatively difficult economic conditions, complicated by internal and external factors, are presented. The publication provides a comparative analysis of the controlled quality indexes (permitted deviation values) presented in the current regulatory documents and standards of the Republic of Belarus and other countries of the world during the erection of reinforced concrete elements of buildings and structures. Based on the analysis of the controlled quality indexes, the main conclusions are formulated, indicating the need to improve the system of national regulatory documents in the field of erection of reinforced concrete structures of buildings, as well as the problems that may arise when several regulatory systems operate simultaneously in the country, and in some cases do not agree with each other.


Currently, prefabricated reinforced concrete structures are widely used for the construction of buildings of various functional purposes. In this regard, has been developed SP 356.1325800.2017 "Frame Reinforced Concrete Prefabricated Structures of Multi-Storey Buildings. Design Rules", which establishes requirements for the calculation and design of precast reinforced concrete structures of frame buildings of heavy, fine-grained and lightweight structural concrete for buildings with a height of not more than 75 m. The structure of the set of rules consists of eight sections and one annex. The document reviewed covers the design of multi-story framed beam structural systems, the elements of which are connected in a spatial system with rigid (partially compliant) or hinged joints and concreting of the joints between the surfaces of the abutting precast elements. The classification of structural schemes of building frames, which according to the method of accommodation of horizontal loads are divided into bracing, rigid frame bracing and framework, is presented. The list of structural elements, such as foundations, columns, crossbars, ribbed and hollow floor slabs and coatings, stiffness elements and external enclosing structures is given; detailed instructions for their design are provided. The scope of the developed set of rules includes all natural and climatic zones of the Russian Federation, except seismic areas with 7 or more points, as well as permafrost zones.


Problems when calculating reinforced concrete structures based on the concrete deformation under compression diagram, which is presented both in Russian and foreign regulatory documents on the design of concrete and reinforced concrete structures are considered. The correctness of their compliance for all classes of concrete remains very approximate, especially a significant difference occurs when using Euronorm due to the different shape and sizes of the samples. At present, there are no methodical recommendations for determining the ultimate relative deformations of concrete under axial compression and the construction of curvilinear deformation diagrams, which leads to limited experimental data and, as a result, does not make it possible to enter more detailed ultimate strain values into domestic standards. The results of experimental studies to determine the ultimate relative deformations of concrete under compression for different classes of concrete, which allowed to make analytical dependences for the evaluation of the ultimate relative deformations and description of curvilinear deformation diagrams, are presented. The article discusses various options for using the deformation model to assess the stress-strain state of the structure, it is concluded that it is necessary to use not only the finite values of the ultimate deformations, but also their intermediate values. This requires reliable diagrams "s–e” for all classes of concrete. The difficulties of measuring deformations in concrete subjected to peak load, corresponding to the prismatic strength, as well as main cracks that appeared under conditions of long-term step loading are highlighted. Variants of more accurate measurements are proposed. Development and implementation of the new standard GOST "Concretes. Methods for determination of complete diagrams" on the basis of the developed method for obtaining complete diagrams of concrete deformation under compression for the evaluation of ultimate deformability of concrete under compression are necessary.


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