scholarly journals Considerations on the Bearing Capacity of Existing Prestressed Concrete Bridges

2020 ◽  
Vol 26 (3) ◽  
pp. 158-161
Author(s):  
Andrei-Mihai Pogány
Keyword(s):  
Bearing Capacity ◽  
Prestressed Concrete ◽  
Road Network ◽  
Building Materials ◽  
Road Traffic ◽  
Concrete Bridges ◽  
Initial Condition ◽  
Prestressed Concrete Bridges ◽  
The Road ◽  
Stable Conditions

AbstractMilitary actions generally unfold rapidly in different operational environments for which the commanding officer has assess the bearing capacity of the prestressed concrete bridges existing in the country’s road network. The bearing capacity is the maximum weight of the predetermined constitution convoy, which may safely circulate on the bridge, in stable conditions, considering the physical condition of the bridge. The paper shows that the bearing capacity will be assessed only through a technical analysis performed by an authorized expert together with a military engineer specialized in genius. This experts report will compare the initial condition of the bridge to the present one. The initial condition is based on the research of the execution design; the year of elaboration; the standard loadings at the moment; proprieties of the used building materials; execution modality, possible alterations occurring during execution as to the initial project. These data, together with the road traffic census, can be obtained from the company administrating the road network where the bridge is located. The current state to be assessed through analysis, calculation and static loading tests, showing if the capacity of the bridge can to support the increase of traffic military vehicle loading and reduction of the bearing capacity due to fatigue phenomena in the reinforcement. The paper proposes that authorities draw up and approve a standard concerning the verification periodicity of the bearing capacity in the existing prestressed concrete bridges.

Assessment of Load-Bearing Capacity of Bridges

2017 ◽  
Vol 259 ◽  
pp. 113-118 ◽  
Author(s):  
Jaroslav Navrátil ◽  
Michal Drahorád ◽  
Petr Ševčík
Keyword(s):  
Bearing Capacity ◽  
Prestressed Concrete ◽  
Iterative Solution ◽  
Concrete Bridges ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Prestressed Concrete Bridges ◽  
Existing Structures ◽  
Non Linear

The paper aims to the determination of load-bearing capacity of reinforced/prestressed concrete bridges subjected to the combination of all components of internal forces according to Eurocode standards for assessment of existing structures. Undoubtedly bridge load rating is laborious hand-iterative process, especially when it comes to reinforced and/or prestressed concrete bridges. The engineer can spend days and weeks trials and errors in the estimation of bridge load-carrying capacity. The problem lies in the determination of load-bearing capacity of cross-section subjected to the combination of normal and shear forces, bending and torsional moments. Due to the different effects of permanent and variable loads and the non-linear behavior of structural materials, the problem becomes non-linear and its solution requires the use of suitable iterative method. Optimized iterative solution was implemented into IDEA StatiCa software and the results are presented in this paper.

scholarly journals Box Type Minor Bridge- As a Sustainable Option Over Small Rivers in Alluvial Region

2019 ◽  
Vol 9 (1) ◽  
pp. 4943-4946
Keyword(s):  
Prestressed Concrete ◽  
Road Network ◽  
Uttar Pradesh ◽  
Concrete Bridges ◽  
Small Rivers ◽  
Masonry Arches ◽  
The Road ◽  
Course Of Action ◽  
Vegetation Water ◽  
Bridge System

Since time immemorial, mankind has been using various techniques to cross the rivers, streams or any depression without closing or obstructing the original flow through a structure called bridge. With the span of time and advancements in civil engineering, several types of bridges have come into existence like wooden, steel, masonry arches, RCC and prestressed concrete bridges. Indian Roads Congress categorizes three types of the bridges on the basis of length i.e. culverts up to 6.0 m, minor bridges above 6.0 m to maximum 60.0 m length and major bridges above 60.0 m. In present scenario, minor bridges over small rivers has become necessary for development and prosperity of nation as most of the roads have to cross small rivers at several places to connect remotest corner of the country. Bridges, though a man made structure, over a period of time become an important part of environment because in most of the cases water flowing below is used for drinking, irrigation and underground recharging. The alluvial region of India spread from Punjab to West Bengal has a peculiar nature because soil is almost soft in nature consisting of mainly sand, clay and silt which is fertile for vegetation. Water retention and its movement condition are high throughout the year. Several type of water bodies which exists in this type of region are pond, small drain, small and medium rivers which drains into the big rivers like Ganga, Yamuna, Ghahgra, Gomti and Sai etc. Since long time, road system on the earthen track and pucca road has been introduced for traffic like chart, chariot and motorised vehicle. There were little number of bridges over major rivers i.e. bridge alone to cross over the river Ganga except in few places like Allahabad, Kanpur and Varanasi and over the Ghaghra Algine bridge, Maghighat, Bhatni. Some bridges were constructed over small and medium rivers in medieval period by local rulers and business men which have now become obsolete. It is found that most of the bridges are of masonry arches wooden and trusses having insufficient water and carriage way. After independence, the road network system has been improved to meet out socio economic needs of people. The new bridges have been constructed with standard road width and sufficient water way. Study has been conducted for existing new constructed bridge system over small river and alluvial region of Uttar Pradesh to set guidance for future course of action in replacing and providing new bridges to optimize the needs of the people. Bridge system being provided over small & minor rivers for the road network for new and replacement of older bridge at different site is varying from place to place. For this purpose, study has been conducted for sustainable option of minor bridges over small rivers discharge upto 300 m3/s. It is found that the box type minor bridges are best option on small & minor rivers.

Reliability Analysis of Prestressed Concrete Bridges in Mexico: Assessment and Live Load Factors Proposal

2021 ◽  
Author(s):  
Rolando Salgado-Estrada ◽  
Sergio A. Zamora-Castro ◽  
Agustín L. Herrera-May ◽  
Yessica A. Sánchez-Moreno ◽  
Yair S. Sánchez-Moreno
Keyword(s):  
Reliability Analysis ◽  
Prestressed Concrete ◽  
Concrete Bridges ◽  
Live Load ◽  
Prestressed Concrete Bridges ◽  
Load Factors

Flexural Vibration of Prestressed Concrete Bridges with Corrugated Steel Webs

2017 ◽  
Vol 17 (02) ◽  
pp. 1750023 ◽  
Author(s):  
Xia-Chun Chen ◽  
Zhen-Hu Li ◽  
Francis T. K. Au ◽  
Rui-Juan Jiang
Keyword(s):  
Finite Element ◽  
Shear Deformation ◽  
Prestressed Concrete ◽  
Natural Frequencies ◽  
Sandwich Beam ◽  
Flexural Vibration ◽  
Concrete Bridges ◽  
Mode Shapes ◽  
Beam Model ◽  
Prestressed Concrete Bridges

Prestressed concrete bridges with corrugated steel webs have emerged as a new form of steel-concrete composite bridges with remarkable advantages compared with the traditional ones. However, the assumption that plane sections remain plane may no longer be valid for such bridges due to the different behavior of the constituents. The sandwich beam theory is extended to predict the flexural vibration behavior of this type of bridges considering the presence of diaphragms, external prestressing tendons and interaction between the web shear deformation and flange local bending. To this end, a [Formula: see text] beam finite element is formulated. The proposed theory and finite element model are verified both numerically and experimentally. A comparison between the analyses based on the sandwich beam model and on the classical Euler–Bernoulli and Timoshenko models reveals the following findings. First of all, the extended sandwich beam model is applicable to the flexural vibration analysis of the bridges considered. By letting [Formula: see text] denote the square root of the ratio of equivalent shear rigidity to the flange local flexural rigidity, and L the span length, the combined parameter [Formula: see text] appears to be more suitable for considering the diaphragm effect and the interaction between the shear deformation and flange local bending. The diaphragms have significant effect on the flexural natural frequencies and mode shapes only when the [Formula: see text] value of the bridge falls below a certain limit. For a bridge with an [Formula: see text] value over a certain limit, the flexural natural frequencies and mode shapes obtained from the sandwich beam model and the classical Euler–Bernoulli and Timoshenko models tend to be the same. In such cases, either of the classical beam theories may be used.

Sign in / Sign up

Export Citation Format

Share Document