Parametric study of load distribution in four-sided concrete box culverts

This paper presents the live load distribution in straight prestressed concrete (PSC) girder bridges with curved deck slab utilizing finite element analyses. Numerical modeling methodology was established and calibrated based on field testing results. A parametric study of 73 cases with varying 6 critical parameters was used to determine a trend over each parameter. Through live load girder distribution factor (GDF) comparisons between the AASHTO LRFD, AASHTO Standard factors and finite element analyses results, both AASHTO live load distribution predicted conservatively in most bridges considered in the parametric study. However, in the bridges with curved slab, GDF was underestimated due to curvature influences. This study proposes a new live load distribution formula to predict rational and conservative live load distribution in PSC girder bridges with curved slab for a preliminary design purpose. The proposed live load distribution provides better live load analysis for the PSC girder bridge with curved slab and ensures the GDF is not underestimated.

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Parametric Study on the Influence of Bays Number and Frame-Span Length on the Redundancy Indices of Reinforced Concrete Structures

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.845.259 ◽

2016 ◽

Vol 845 ◽

pp. 259-264

Author(s):

Mutiara Puspahati Cripstyani ◽

Stefanus Adi Kristiawan ◽

Edy Purwanto

Keyword(s):

Reinforced Concrete ◽

Parametric Study ◽

Load Distribution ◽

Three Dimensional ◽

Alternative Possibilities ◽

Span Length ◽

Reinforced Concrete Structure ◽

Strength Index ◽

Capacity Curves ◽

Variation Index

The role of redundancy in a structure that receives earthquake load is very important. It provides alternative possibilities of load distribution in the event of a local collapse of the system before it reaches the total collapse of the structure. This mechanism of load distribution provides time for the users of the building to escape. A parametric study is carried out to investigate the effect of bays number and frame-span length in order to identify factors affecting the redundancy of the reinforced concrete structural system. Non-linear analysis (pushover) using SAP2000 on three-dimensional structural frames system are performed to obtain the capacity curves of the structures from which redundancies are calculated. Redundancy on the system is determined into two redundancy indices i.e. redundancy strength index (rs) and redundancy variation index (rv) which are, respectively, deterministic and probabilistic measure of the stuctural redundancy. This study points out that frame-span length has more significant effect on redundancy indices compared to the bays number. It is also shown that a reinforced concrete structure with a higher redundancy strength index tends to have a lower redundancy variation index.

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Effect of Soil Fill on the Load Distribution Characteristics of RC Skew Box Culverts for Road Under Bridge Design

Lecture Notes in Civil Engineering - Advances in Construction Materials and Sustainable Environment ◽

10.1007/978-981-16-6557-8_27 ◽

2021 ◽

pp. 341-353

Author(s):

Shimol Philip ◽

R. Rakendu ◽

Rajesh Lal

Keyword(s):

Load Distribution ◽

Distribution Characteristics ◽

Bridge Design ◽

Box Culverts

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Load Distribution Factors for Curved Concrete Slab-on-Steel I-Girder Bridges

10.32920/ryerson.14665275 ◽

2021 ◽

Author(s):

Mohammed A. Al-Hashimy

Keyword(s):

Parametric Study ◽

Load Distribution ◽

Concrete Slab ◽

Steel Bridges ◽

Urban Systems ◽

Lateral Bending ◽

Curved Bridges ◽

Horizontally Curved ◽

Girder Bridges ◽

Curved Steel

The use of complex interchanges in modern highway urban systems have increased recently in addition to the desire to conform to existing terrain; both have led to increase the demand for horizontally curved bridges. One type of curved bridges consists of composite concrete deck over steel I-girders which has been the preferred choice due to its simplicity in fabrication, transportation and erection. Although horizontally curved steel bridges constitute roughly one-third of all steel bridges being erected today, their structural behavior still not well understood. Due to its geometry, simple presence of curvature in curved bridges produces non uniform torsion and consequently, lateral bending moment (warping or bi-moment) in the girder flanges. The presence of the lateral bending moments would significantly complicate the analysis and the design of the structure. Hence, a parametric study is required to scrutinize a simplified method in designing horizontally curved steel I-girder bridges. A parametric study is conducted, using the finite-element analysis software "SAP2000", to examine the key parameters that may influence the load distribution on the curved composite steel girders. Based on the data generated from the parametric study, sets of empirical equations are developed for the moment and shear distribution factors for straight and curved steel I-girder bridges when subjected to the Canadian Highway Bridge Design Code (HCHBDC) truck loading.

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Investigation of Load Distribution Factors for Simply-Supported Composite Multiple Box Girder Bridges

10.32920/ryerson.14651502.v1 ◽

2021 ◽

Author(s):

Siham Kadhim Jawad

Keyword(s):

Finite Element ◽

Parametric Study ◽

Load Distribution ◽

Shear Force ◽

Bending Moment ◽

Box Girder Bridges ◽

Box Girder ◽

Simply Supported ◽

Girder Bridges ◽

Load Distribution Factors

Composite box-girder bridges are recently used in modern highway urban system because of their profitable and structural aptitude advantages. North Americans Codes of Practice specify empirical equations for girder moment and shear forces in such bridges in the form of live load distribution factors. These factors were proven to be conservative in some cases and underestimate the response in other cases. Therefore, an extensive parametric study, using the finite-element modeling, was conducted to examine the key parameters that influence the load distribution factors of such bridges. A total of 276 prototype bridges were analyzed to evaluate girder bending moment, shear force and deflection distribution factors for simply-supported composite multiple box-girder bridges when subjected to CHBDC truck loading. Design parameters considered in this study were bridges span length, numbers of design lanes, number of box girders and girder spacing. Based on the data generated from parametric study, sets of simple empirical expressions were developed for bending moment; shear force and deflection distribution factors for such bridges. A correlation between the finite-element results with CHBDC and AASHTO-LRFD empirical expressions showed the former are more reliable in structural design of composite box-girder bridges.

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Load Distribution Factors for Curved Concrete Slab-on-Steel I-Girder Bridges

10.32920/ryerson.14665275.v1 ◽

2021 ◽

Author(s):

Mohammed A. Al-Hashimy

Keyword(s):

Parametric Study ◽

Load Distribution ◽

Concrete Slab ◽

Steel Bridges ◽

Urban Systems ◽

Lateral Bending ◽

Curved Bridges ◽

Horizontally Curved ◽

Girder Bridges ◽

Curved Steel

The use of complex interchanges in modern highway urban systems have increased recently in addition to the desire to conform to existing terrain; both have led to increase the demand for horizontally curved bridges. One type of curved bridges consists of composite concrete deck over steel I-girders which has been the preferred choice due to its simplicity in fabrication, transportation and erection. Although horizontally curved steel bridges constitute roughly one-third of all steel bridges being erected today, their structural behavior still not well understood. Due to its geometry, simple presence of curvature in curved bridges produces non uniform torsion and consequently, lateral bending moment (warping or bi-moment) in the girder flanges. The presence of the lateral bending moments would significantly complicate the analysis and the design of the structure. Hence, a parametric study is required to scrutinize a simplified method in designing horizontally curved steel I-girder bridges. A parametric study is conducted, using the finite-element analysis software "SAP2000", to examine the key parameters that may influence the load distribution on the curved composite steel girders. Based on the data generated from the parametric study, sets of empirical equations are developed for the moment and shear distribution factors for straight and curved steel I-girder bridges when subjected to the Canadian Highway Bridge Design Code (HCHBDC) truck loading.

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Shear distribution in simply supported skew composite bridges

Canadian Journal of Civil Engineering ◽

10.1139/l95-132 ◽

1995 ◽

Vol 22 (6) ◽

pp. 1143-1154 ◽

Cited By ~ 13

Author(s):

Tarek Ebeido ◽

John B. Kennedy

Keyword(s):

Parametric Study ◽

Load Distribution ◽

Experimental Program ◽

Distribution Factor ◽

Simply Supported ◽

Shear Distribution ◽

Truck Loading ◽

Composite Bridges ◽

Bridge Models ◽

Composite Steel

Composite steel–concrete bridges remain one of the most common types built. Proper design of new bridges and evaluation of existing bridges requires accurate prediction of their structural response to truck loads. The American Association of State Highway and Transportation Officials has traditionally applied a load distribution factor for both moment and shear. The Ontario Highway Bridge Design Code (OHBDC) considers several parameters in establishing load distribution factors for moment. However, the method is limited to bridges with skew parameters less than a certain value specified in the code. The presence of skew reduces the longitudinal moments in the girders. However, it also causes high concentration of shear in the girder closest to the obtuse corner and reduces shear concentration in the girder closest to the acute corner as well as in the interior girders. Therefore, shear should be considered in the design of such bridges. In this paper, the influence of skew on the shear distribution factor is investigated. The influences of other factors such as girder spacing, bridge aspect ratio, number of lanes, number of girders, end diaphragms, and intermediate cross-beams are presented. An experimental program was conducted on six simply supported skew composite steel–concrete bridge models. Results from a finite element analysis showed excellent agreement with the experimental results. An extensive parametric study was conducted on prototype composite bridges subjected to OHBDC truck loading. The parametric study included more than 400 cases. The data generated were used to develop empirical formulas for shear distribution factors for OHBDC truck loading and also for dead load. An illustrative example is presented. Key words: bridges, codes of practice, composite, distribution, reaction, reinforced concrete, shear, skew, structural engineering, tests.

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A Parametric Study of Piled Raft Foundation in Clay Subjected to Concentrated Loading

International Journal of Integrated Engineering ◽

10.30880/ijie.2021.13.04.025 ◽

2021 ◽

Vol 13 (4) ◽

Author(s):

Chong Yi Hong ◽

◽

Lee Min Lee ◽

Kok Sien Ti ◽

Wong Soon Yee ◽

...

Keyword(s):

Parametric Study ◽

Load Distribution ◽

Differential Settlement ◽

Concentrated Load ◽

Piled Raft ◽

Piled Raft Foundation ◽

Raft Foundation ◽

Controlling Parameter ◽

Sandy Material ◽

Concentrated Loading

The use of piled raft foundation in building and infrastructure constructions is increasingly popular because of its effectiveness in reducing overall and differential settlements. Parameters influencing the performance of the piled raft foundation need to be comprehended in order to optimize the design of the piled raft system. Most of the current available literature focused on the piled raft foundation subjected to a uniform distributed load in sandy material. This parametric study aims to provide insights into the performance of the piled raft foundations subjected to concentrated loading in clay. A series of 2D finite element analyses were performed to investigate the influencing parameters affecting the load distribution and settlement behaviour of the piled raft. The results suggested that increases in both pile length and raft thickness, as well as a decrease in pile spacing would reduce the differential settlement of the piled raft. Comparatively, raft thickness was the most significant controlling parameter affecting the differential settlement. The study also revealed the importance of placing the pile nearer to the location of concentrated load as it would yield a more uniform load distribution, and hence a lower differential settlement.

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