scholarly journals Justification of the development and application of express assessment programs for road bridges when heavy vehicles pass through them

2021 ◽  
Vol 17 (4) ◽  
pp. 315-323
Author(s):  
Evgeny A. Lugovtsev
Keyword(s):  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Rapid Assessment ◽  
Technical Condition ◽  
Heavy Vehicles ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Bridge Structures ◽  
Pass Through ◽  
State Registration

The theoretical prerequisites for justifying the development of two rapid assessment programs for road bridges to quickly determine the possibility of passing heavy vehicles on road bridge structures of a split and non-split system, made of wood, metal, steel-reinforced concrete, reinforced concrete with stressed and non-stressed reinforcement, according to the measured angle of rotation of their support sections, taking into account their actual operational condition, are presented. The programs implemented an experimental and analytical method for assessing the technical condition of road bridges for reliability. The features, conditions of application, positive and negative aspects of each version of the program are revealed. The creation of two variants of programs is due to, on the one hand, the need to ensure the safety of the driver of the vehicle and the bridge structure, and on the other hand, the need to guarantee the possibility of safe passage of heavy vehicles, both under the conditions of the load-bearing capacity of superstructures and the load-bearing capacity of road bridge supports, taking into account their actual operational condition. Both developed calculation programs were implemented by using a personal computer and certificates of state registration of computer programs were obtained. The developed programs will be used as part of the modernized IR-AM measuring complex.

Assessment of the Load-Bearing Capacity of Reinforced Concrete Rack With a Composite Cover of a Constructive Element of Bridge Supports

2021 ◽  
pp. 86-96
Author(s):  
В. А. Шендрик
Keyword(s):  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Composite Shell ◽  
Structural Elements ◽  
Joint Work ◽  
Load Bearing Capacity ◽  
Concrete Core ◽  
Load Bearing ◽  
Fiberglass Shell ◽  
Bridge Structures

Постановка задачи. Рассматривается задача разработки методики расчета несущей способности гибридных железобетонных стоек, предназначенных для стоечных опор мостовых сооружений с внешними композитными (стеклопластиковыми) оболочками. Результаты. Сформулированы теоретические зависимости для определения напряжений и относительных деформаций конструктивных элементов гибридной стойки в продольном и поперечном направлениях. Разработанные формулы учитывают совместную работу всесторонне сжатого бетонного ядра с анизотропной стеклопластиковой оболочкой, но не учитывают силовое и средовое воздействие непосредственно на композитную оболочку. Выводы. Полученные теоретические зависимости работы элементов гибридной стойки позволяют разработать методику расчета несущей способности гибридных стоек для опор мостовых сооружений. Результаты исследования предлагается применять в расчетах гибридных стоечных опор мостовых сооружений с элементами из композитных материалов. Statement of the problem. The problem of development of a technique of calculation of the load-bearing capacity of the hybrid reinforced concrete racks intended for rack supports of bridge constructions with external composite (fiberglass) covers is explored. Results. Theoretical dependences for identifying the stresses and relative deformations of structural elements of a hybrid rack in the longitudinal and cross directions are formulated. The resulting formulas take into consideration the joint work of a comprehensively compressed concrete core with an anisotropic fiberglass shell, but do not account for the force and environmental effects directly on the composite shell. Conclusions. The resulting theoretical dependences of the operation of the elements of the hybrid rack enable us to develop a method for calculating the load-bearing capacity of hybrid racks for the supports of bridge structures. It is suggested that the results of the research are applied in calculations of hybrid rack supports of bridge constructions with elements from composite materials.

Experimental and numerical investigation on the vertical bearing behavior of discrete connected new-type precast reinforced concrete floor system

2020 ◽  
Vol 23 (11) ◽  
pp. 2276-2291
Author(s):  
Rui Pang ◽  
Yibo Zhang ◽  
Longji Dang ◽  
Lanbo Zhang ◽  
Shuting Liang
Keyword(s):  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Cover Plate ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Concrete Floor ◽  
New Type ◽  
Vertical Bearing ◽  
Floor System ◽  
Bearing Behavior

This article proposes a new type of discrete connected precast reinforced concrete diaphragm floor system that consists of precast flat slabs and slab joint connectors. An experimental investigation of discrete connected new-type precast reinforced concrete diaphragm under a vertical distributed static load was conducted, and the effect of slab joint connectors on the load-bearing capacity was evaluated. Then, a finite element analysis of discrete connected new-type precast reinforced concrete diaphragm, precast reinforced concrete floors without slab connectors, and cast-in-situ reinforced concrete floor were performed to understand their working mechanism and determine the differences in load-bearing behavior. The results indicate that the load-bearing capacity and stiffness of discrete connected new-type precast reinforced concrete diaphragm increase considerably as the hairpin and cover plate hybrid slab joint connectors can efficiently connect adjacent precast slabs and enable them to work together under a vertical load by transmitting the shear and moment forces in the orthogonal slab laying direction. The deflection of discrete connected new-type precast reinforced concrete diaphragm in orthogonal slab laying direction is mainly caused by the opening deformation of the slab joint and the rotational deformation of the precast slabs. This flexural deformation feature can provide reference for establishing the bending stiffness analytical model of discrete connected new-type precast reinforced concrete diaphragm in orthogonal slab laying direction, which is vitally important for foundation of the vertical bearing capacity and deformation calculation method. The deflection and crack distribution patterns infer that the discrete connected new-type precast reinforced concrete diaphragm processes the deformation characteristic of two-way slab floor, which can provide a basis for the theoretical analysis of discrete connected new-type precast reinforced concrete diaphragm.

scholarly journals Load Bearing Capacity Calculation of the System “Reinforced Concrete Beam – Deformable Base” under Torsion with Bending

2019 ◽  
Vol 97 ◽  
pp. 04059 ◽  
Author(s):  
Alexey Dem’yanov ◽  
Vladymir Kolchunov ◽  
Igor Iakovenko ◽  
Anastasiya Kozarez
Keyword(s):  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Cross Sections ◽  
Concrete Beam ◽  
Equations Of State ◽  
Reinforced Concrete Beam ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Deformable Base ◽  
The Relationship

It is presented the formulation and solution of the load bearing capacity of statically indeterminable systems “reinforced concrete beam – deformable base” by spatial cross-sections under force and deformation effects. The solution of problem is currently practically absent in general form. It has been established the relationship between stresses and strains of compressed concrete and tensile reinforcement in the form of diagrams. The properties of the base model connections are described based on a variable rigidity coefficient. It is constructed a system of n equations in the form of the initial parameters method with using the modules of the force (strain) action vector. The equations of state are the dependences that establish the relationship between displacements which are acting on the beam with load. Constants of integration are determined by recurrent formulas. It makes possible to obtain the method of initial parameters in the expanded form and, consequently, the method of displacements for calculating statically indefinable systems. The values of the effort obtained could be used to determine the curvature and rigidity of the sections in this way. It is necessary not to set the vector modulusP, the deformation is set in any section (the module is considered as an unknown) during the problem is solving. This allows us to obtain an unambiguous solution even in the case when the dependence M–χ has a downward section, i.e one value of moment can correspond to two values of curvature.

Probabilistic Assessment of Historic Reinforced Concrete Bridge

2016 ◽  
Vol 821 ◽  
pp. 767-773
Author(s):  
Jan Krejsa ◽  
Miroslav Sýkora ◽  
Michal Drahorád
Keyword(s):  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Probabilistic Method ◽  
Concrete Bridge ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Reinforced Concrete Bridge ◽  
Factor Method ◽  
Partial Factor Method ◽  
Partial Factor

This paper is aimed at the reliability analysis of an existing reinforced concrete bridge from 1908. The load bearing capacity is assessed in accordance with valid standards using the partial factor method and probabilistic approach. Load bearing capacities obtained by these methods are critically compared. The application of probabilistic method leads to 40 % higher load bearing capacity then the partial factor method used for structural design.

scholarly journals Research on Intelligent Evaluation System of Load-bearing Capacity of Existing Reinforced Concrete Bridge

2020 ◽  
Vol 165 ◽  
pp. 04056
Author(s):  
An Zhao ◽  
Qiang Xu ◽  
Jianyong Song
Keyword(s):  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Evaluation System ◽  
Limit State ◽  
Concrete Bridge ◽  
Parametric Modelling ◽  
Limit States ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Reinforced Concrete Bridge

The intelligent evaluation system of existing reinforced concrete bridge “BLP” is a special software for the load-bearing capacity rapid analysis and evaluation of the existing reinforced concrete bridge, which was developed by the Highway Research Institute of the Ministry of Transport. Based on the parametric modelling method, it can quickly and easily establish the finite element plane model of the bridge structure for the static analysis of ultimate bearing capacity limit states and serviceability limit state, under variety norms. And it can easily and quickly build variable-section beams and rebars, with the special module. According to the comprehensive modification method of the load-bearing capacity evaluation, it can automatically recommend checking sections, and automatically calculate partial modification coefficient of resistance effect, and conveniently judge the safety coefficient of the sections, and quickly get the results of bridge load-bearing capacity. In summary, this system can significantly improve the work efficiency and accuracy of load-bearing capacity for exiting reinforced concrete bridge. This paper introduces in detail the characteristics of the intelligent analysis technology, calculation principle and real bridge application examples of the system.

Simulation of Performance of CFST Elements Containing Differentiated Profile Tubes Filled with Reinforced Concrete

2019 ◽  
Vol 968 ◽  
pp. 281-287 ◽  
Author(s):  
Glib Vatulia ◽  
Alexey Lobiak ◽  
Vitaliy Chernogil ◽  
Mariia Novikova
Keyword(s):  
Finite Element ◽  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Accurate Method ◽  
Iteration Algorithm ◽  
Stress Strain ◽  
Load Bearing Capacity ◽  
Limiting State ◽  
Load Bearing ◽  
The Core

The approach to calculating CFST elements is considered in which physical non-linearity of materials, geometric non-linearity of the tube and the effect of increasing the strength of the core are taken into account. Finite element models are developed and proposed as the basis for more accurate method of calculating concrete-filled steel elements consisting of differentiated profile tubes filled with reinforced concrete. The technique uses a step iteration algorithm involving analytical dependencies and finite element simulation. The criterion for determining the load bearing capacity of CFST elements was the achievement of the stresses in the tube of the characteristic strength. The possibility of estimating the load bearing capacity of elements by limiting stresses in the core concrete is also implemented. The result of the calculations was obtaining the stress-strain and limiting state of the differentiated profile tubes with CFST elements, and graphic analysis of the regularities of stress redistribution at different stages of performance of columns. In general, with the accepted problem statement we could establish the exact stress-strain state, take into account the elastic-plastic deformations of concrete, its cracking and destruction, and geometric nonlinearity of the tube. The effect of performance of the corrugated sheet as a tube was established.

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