scholarly journals Bridge roughness index as an indicator of bridge dynamic amplification

2006 ◽  
Vol 84 (12) ◽  
pp. 759-769 ◽  
Author(s):  
Eugene OBrien ◽  
Yingyan Li ◽  
Arturo González
Keyword(s):  
Roughness Index ◽  
Dynamic Amplification

scholarly journals Torrential Flood Water Management: Rainwater Harvesting through Relation Based Dam Suitability Analysis and Quantification of Erosion Potential

2021 ◽  
Vol 10 (1) ◽  
pp. 27
Author(s):  
Bilal Ahmad Munir ◽  
Sajid Rashid Ahmad ◽  
Raja Rehan
Keyword(s):  
Sediment Yield ◽  
Soil Loss ◽  
Rainwater Harvesting ◽  
Suitability Analysis ◽  
Valley Bottom ◽  
The North ◽  
Roughness Index ◽  
Dam Site ◽  
Very High

In this study, a relation-based dam suitability analysis (RDSA) technique is developed to identify the most suitable sites for dams. The methodology focused on a group of the most important parameters/indicators (stream order, terrain roughness index, slope, multiresolution valley bottom flatness index, closed depression, valley depth, and downslope gradient difference) and their relation to the dam wall and reservoir suitability. Quantitative assessment results in an elevation-area-capacity (EAC) curve substantiating the capacity determination of selected sites. The methodology also incorporates the estimation of soil erosion (SE) using the Revised Universal Soil Loss Equation (RUSLE) model and sediment yield at the selected dam sites. The RDSA technique identifies two suitable dam sites (A and B) with a maximum collective capacity of approximately 1202 million m3. The RDSA technique was validated with the existing dam, Gomal-Zam, in the north of Sanghar catchment, where RDSA classified the Gomal-Zam Dam in a very high suitability class. The SE estimates show an average of 75 t-ha−1y−1 of soil loss occurs in the study area. The result shows approximately 298,073 and 318,000 tons of annual average sediment yield (SY) will feed the dam A and B respectively. The SE-based sediment yield substantiates the approximate life of Dam-A and Dam-B to be 87 and 90 years, respectively. The approach is dynamic and can be applied for any other location globally for dam site selection and SE estimation.

The dynamic amplification factors for continuous beam bridges along high-speed railways

2021 ◽  
pp. 136943322110032
Author(s):  
Lin Ma ◽  
Wei Zhang ◽  
Steve C.S. Cai ◽  
Shaofan Li
Keyword(s):  
Fundamental Frequency ◽  
High Speed ◽  
Continuous Beam ◽  
Empirical Formulas ◽  
High Speed Railway ◽  
Amplification Factors ◽  
Girder Bridges ◽  
Continuous Beam Bridge ◽  
Train Speed ◽  
Dynamic Amplification

In this paper, the dynamic amplification factors (DAFs) of high-speed railway continuous girder bridges are studied. The vehicle-bridge interactions (VBIs) of 13 concrete continuous girder bridges with spans ranging from 48 to 130 m are analyzed, the influences of the train speed, the train marshalling and the bridge fundamental frequency on the DAF are investigated, and the DAF design standard for high-speed railway bridges is discussed. The results indicate that for the continuous beam bridge whose fundamental frequency is less than 3.0 Hz, the maximum DAF is no more than 1.15; while for the bridge examples with a fundamental frequency larger than 3.0 Hz, the maximum DAF reaches 1.25 because the resonance occurs at high train speed. The empirical formulas of the DAFs in the Japan Railway Technical Research Institute (JRTRI) code could provide a conservative estimation of the DAFs of high-speed railway continuous bridges.

Analysis of test blanket module attachments under electromagnetic loads by using a dynamic amplification factor envelope

2018 ◽  
Vol 136 ◽  
pp. 1247-1251
Author(s):  
Raúl Muñoz ◽  
Francisco J. Calvo ◽  
Sergio Sádaba ◽  
Ana M. Gil ◽  
Javier Rodríguez ◽  
...  
Keyword(s):  
Amplification Factor ◽  
Dynamic Amplification Factor ◽  
Dynamic Amplification

Effects of international roughness index on vehicle emissions

2021 ◽  
Vol 15 (1) ◽  
pp. 41
Author(s):  
Ernesto Ferreira Nobre Junior ◽  
Arielle Elias Arantes ◽  
Priscilla Oliveira Azevedo
Keyword(s):  
Vehicle Emissions ◽  
International Roughness Index ◽  
Roughness Index

scholarly journals EFFECT OF SOIL TILLAGE AND PLANT RESIDUE ON SURFACE ROUGHNESS OF AN OXISOL UNDER SIMULATED RAIN

2015 ◽  
Vol 39 (1) ◽  
pp. 268-278 ◽  
Author(s):  
Elói Panachuki ◽  
Ildegardis Bertol ◽  
Teodorico Alves Sobrinho ◽  
Paulo Tarso Sanches de Oliveira ◽  
Dulce Buchala Bicca Rodrigues
Keyword(s):  
Surface Roughness ◽  
Soil Surface ◽  
Conventional Tillage ◽  
Plant Residue ◽  
Soil Tillage ◽  
No Tillage ◽  
Maize Crop ◽  
Minimum Tillage ◽  
Roughness Index ◽  
Simulated Rain

Surface roughness of the soil is formed by mechanical tillage and is also influenced by the kind and amount of plant residue, among other factors. Its persistence over time mainly depends on the fundamental characteristics of rain and soil type. However, few studies have been developed to evaluate these factors in Latossolos (Oxisols). In this study, we evaluated the effect of soil tillage and of amounts of plant residue on surface roughness of an Oxisol under simulated rain. Treatments consisted of the combination of the tillage systems of no-tillage (NT), conventional tillage (CT), and minimum tillage (MT) with rates of plant residue of 0, 1, and 2 Mg ha-1 of oats (Avena strigosa Schreb) and 0, 3, and 6 Mg ha-1 of maize (Zea mays L.). Seven simulated rains were applied on each experimental plot, with intensity of 60±2 mm h-1 and duration of 1 h at weekly intervals. The values of the random roughness index ranged from 2.94 to 17.71 mm in oats, and from 5.91 to 20.37 mm in maize, showing that CT and MT are effective in increasing soil surface roughness. It was seen that soil tillage operations carried out with the chisel plow and the leveling disk harrow are more effective in increasing soil roughness than those carried out with the heavy disk harrow and leveling disk harrow. The roughness index of the soil surface decreases exponentially with the increase in the rainfall volume applied under conditions of no tillage without soil cover, conventional tillage, and minimum tillage. The oat and maize crop residue present on the soil surface is effective in maintaining the roughness of the soil surface under no-tillage.

scholarly journals Dynamic Behavior of Tied-Arch Bridges under the Action of Moving Loads

2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
Paolo Lonetti ◽  
Arturo Pascuzzo ◽  
Alessandro Davanzo
Keyword(s):  
Dynamic Behavior ◽  
Structural Characteristics ◽  
Moving Load ◽  
Sensitivity Analyses ◽  
Impact Factors ◽  
Moving Loads ◽  
Centripetal Acceleration ◽  
Design Variables ◽  
Dynamic Amplification ◽  
Arch Bridges

The dynamic behavior of tied-arch bridges under the action of moving load is investigated. The main aim of the paper is to quantify, numerically, dynamic amplification factors of typical kinematic and stress design variables by means of a parametric study developed in terms of the structural characteristics of the bridge and moving loads. The basic formulation is developed by using a finite element approach, in which refined schematization is adopted to analyze the interaction between the bridge structure and moving loads. Moreover, in order to evaluate, numerically, the influence of coupling effects between bridge deformations and moving loads, the analysis focuses attention on usually neglected nonstandard terms in the inertial forces concerning both centripetal acceleration and Coriolis acceleration. Sensitivity analyses are proposed in terms of dynamic impact factors, in which the effects produced by the external mass of the moving system on the dynamic bridge behavior are evaluated.

Detecting and Correcting Localized Roughness Features

2015 ◽  
Vol 2525 (1) ◽  
pp. 71-78 ◽  
Author(s):  
Gary J. Higgins
Keyword(s):  
Asphalt Pavements ◽  
Minimum Length ◽  
Accurate Data ◽  
Department Of Transportation ◽  
Profile Data ◽  
Diamond Grinding ◽  
Significant Difference ◽  
Roughness Index ◽  
Colorado Department

Data collected by inertial profilers on new asphalt pavements in Colorado in 2012 were used to analyze the effectiveness of the localized roughness specification in Colorado. For the analyzed projects, data were collected before any corrections were made as well as after diamond grinding had been performed to remove areas of localized roughness. The data indicated that localized roughness features having a half-car roughness index (HRI) lower than 175 in./mi were rarely addressed during correction. However, about half the localized roughness features that had an HRI of 175 to 200 in./mi were successfully addressed during correction. Localized roughness features having an HRI greater than 200 in./mi appeared to be successfully addressed during correction. The analysis indicated a significant difference in the localized roughness locations identified by AASHTO R 54 and the Colorado Department of Transportation (DOT) method of detecting localized roughness. The Colorado DOT procedure specifies a minimum length for a roughness feature that is to be corrected, but AASHTO R 54 does not. This paper shows that collecting accurate profile data and analyzing the data to determine localized roughness locations are not enough. The identified locations must be correctly marked on the pavement in the field so that the feature does not cause localized roughness. This paper presents a procedure not only for collecting accurate data but also for accurately marking the roughness features in the field. It is shown that it is possible to locate and correct localized roughness accurately to the current thresholds as set by AASHTO R 54.

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