Roadway-Vehicle Interaction, Physical Indexes, and Human Judgment of Ride Quality

1997 ◽  
Vol 1570 (1) ◽  
pp. 55-59 ◽  
Author(s):  
Chiu Liu ◽  
Robert Herman
Keyword(s):  
Ride Quality ◽  
Physical Parameters ◽  
Human Judgment ◽  
International Roughness Index ◽  
Moving Vehicle ◽  
Roughness Index ◽  
Static Profile ◽  
Relationship Of ◽  
The Relationship ◽  
Analytical Expressions

Present serviceability index (PSI) modeling has been an important subject for decades. Other dynamic indexes characterizing a roadway such as the international roughness index (IRI), averaged rectified slope (ARS), and averaged rectified speed (ARV) have been proposed and studied. However, the roles played by these indexes in the interaction between road, vehicle, and human ratings have not been made clear. A unified physical model linking the static profile of a roadway and the dynamic response of a vehicle to the profile to the serviceability index of the roadway is presented here. Analytical expressions for jerk index, acceleration index, ARV, ARS, and IRI are derived from the developed model in terms of the physical parameters for roadways and the dynamic characteristics of a vehicle. Then a linear relation between the PSI and the logarithm of the jerk index is proposed. Using the jerk index computed from field profile data, the linear functional form for the PSI is verified, and regression R2 values higher than 0.94 are obtained for various types of pavements. The same analysis is performed for other dynamic indexes, and the R2 values are found to be approximately in the range from 0.70 to 0.80. These results indicate that the theoretical model correctly predicts and explains the human rating of ride quality and that the jerk experienced by raters in a moving vehicle dictates the ratings. Moreover, the relationship of the static parameters of roadway profiles with human ratings is discussed using the conventional approach.

Effects of the International Roughness Index and Rut Depth on Crash Rates

2018 ◽  
Vol 2672 (40) ◽  
pp. 418-429 ◽  
Author(s):  
Michael Mamlouk ◽  
Mounica Vinayakamurthy ◽  
B. Shane Underwood ◽  
Kamil E. Kaloush
Keyword(s):  
Pavement Management ◽  
Ride Quality ◽  
International Roughness Index ◽  
Accident Rate ◽  
Crash Data ◽  
Crash Rates ◽  
Vehicle Operation ◽  
Roughness Index ◽  
Pavement Distresses ◽  
The Relationship

Pavement distresses directly affect ride quality, and indirectly contribute to driver distraction, vehicle operation, and accidents. In this study, analysis was performed on highways in the states of Arizona, North Carolina, and Maryland to investigate the relationship between accident rate and pavement ride quality (roughness) and rut depth. Two main types of data were collected: crash data from the accident records and International Roughness Index (IRI) and rut depth data from the pavement management system database in each state. Crash rates were calculated using the U.S. Department of Transportation method, which is the number of accidents per 100 million vehicle-miles of travel. Sigmoidal function regression analysis was performed to study the relationship between crash rate and both IRI and rut depth. In all cases, the crash rate did not show substantial increases until an IRI value of 210 inches/mile or a critical rut depth of 0.4 inches. When the IRI or rut depth increased above these values the crash rate increased. This is a key conclusion that provides empirically derived thresholds for IRI and rut depth to reducing the accident rate.

scholarly journals PEMANFAATAN APLIKASI SMARTPHONE UNTUK MENGUKUR KEMANTAPAN PERMUKAAN JALAN BERDASARKAN INTERNATIONAL ROUGHNESS INDEX

2020 ◽  
Vol 19 (3) ◽  
pp. 205-214
Author(s):  
Arief Setiawan ◽  
Novita Pradani ◽  
Ferra Claudia Masoso
Keyword(s):  
Segment Length ◽  
Android Application ◽  
Smartphone Applications ◽  
International Roughness Index ◽  
Surface Conditions ◽  
Software Applications ◽  
Measurement Results ◽  
Roughness Index ◽  
Technological Developments ◽  
The Relationship

Abstract An assessment of road surface conditions is needed to determine an appropriate road evaluation program. One of the parameters used is the International Roughness Index or IRI. Currently, technological developments encourage the use of smartphone applications as a tool to determine the value of IRI. Comparisons between IRIs obtained using tools, such as roughometers, and IRIs obtained from software applications have not been made. The purpose of this study was to analyze the relationship between the results of the measurement of the roughometer and the results of the Android application Roadbump Pro. This research was carried out on the Sam Ratulangi Road in Palu City, with a segment length of 600 meters and analyzed per 100 meters. The results of this study indicate that smartphone applications provide good IRI measurement results, so they can be used in road stability assessments. In addition, the type of survey vehicle did not have a significant effect on IRI measurements. Keywords: smartphone, International Roughness Index, roughometer, Roadbump, road stability  Abstrak Penilaian kondisi permukaan jalan diperlukan untuk menentukan program evaluasi jalan yang tepat. Salah satu parameter yang digunakan adalah International Roughness Index atau IRI. Saat ini, perkembangan teknologi mendorong penggunaan aplikasi smartphone sebagai alat bantu untuk menentukan nilai IRI. Perbandingan antara IRI yang diperoleh dengan menggunakan alat bantu, seperti roughometer, dan IRI yang diperoleh dari aplikasi perangkat lunak belum dilakukan. Tujuan penelitian ini adalah menganalisis hubungan antara hasil pengukuran alat roughometer dan hasil aplikasi android Roadbump Pro. Penelitian ini dilakukan di ruas Jalan Sam Ratulangi di Kota Palu, dengan panjang segmen 600 meter dan dianalisis per 100 meter. Hasil penelitian ini menunjukkan bahwa aplikasi smartphone memberikan hasil pengukuran IRI yang baik, sehingga dapat digunakan dalam penilaian kemantapan jalan. Selain itu, jenis kendaraan survei tidak memberikan pengaruh yang signifikan terhadap pengukuran IRI. Kata-kata kunci: smartphone, International Roughness Index, roughometer, Roadbump, kemantapan jalan

Full-Car Roughness Index as Summary Roughness Statistic

2005 ◽  
Vol 1905 (1) ◽  
pp. 148-156 ◽  
Author(s):  
Renato A. C. Capuruço ◽  
Tarek Hegazy ◽  
Susan L. Tighe ◽  
Sameh Zaghloul
Keyword(s):  
Mechanical Response ◽  
Pavement Management ◽  
Ride Quality ◽  
Management Decision ◽  
International Roughness Index ◽  
Front Suspension ◽  
Car Model ◽  
Roughness Index ◽  
Wheel Model ◽  
Management Decision Making

The international roughness index (IRI) and the half-car roughness index (HRI) are the two commonly used roughness indices for pavement management, decision making, prioritization, budgeting, and planning. This work presents a new statistic, termed the full-car roughness index (FRI), for calculation of roughness from longitudinal pavement profiles. FRI is calculated from a single, equivalent profile that is a composite of four corner profiles based on both civil and mechanical engineering principles. More specifically, the full-car (four-wheel) model combines the rear and front suspension systems through an interdependent relation of motion with the longitudinal axle. To validate this model, the FRI values for different pavement sections are determined for sampling roughness measurements from several states and provinces. Then, the behavior of FRI is compared with that of IRI and HRI. The methodology of assessment uses a Monte Carlo simulation for calibration and validation of the index. Correlations derived from this sensitivity analysis on the basis of regression analysis arrive at a conversion chart to propose conversion values from these indices to FRIs. Overall, this paper suggests that the mechanical response of the proposed full-car model is more representative of the characteristics of a real vehicle than the response of a quarter- or half-car model. The results also indicate that FRI is less sensitive to the governing factors that account for the quarter-car simulation and thus provides an index that is unique, insightful, and more effective in the characterization of ride quality.

scholarly journals FORMATION OF MATHEMATICAL APPARATU FOR THE METHODOLOGY OF EMERGENCY PREVENTION ON SOLID WASTE LANDFILL WITH TECHNOLOGICAL EQUIPMENT

2020 ◽  
Vol 1 (154) ◽  
pp. 100-107 ◽  
Author(s):  
N. Rashkevich
Keyword(s):  
Mathematical Model ◽  
Solid Waste ◽  
Living Conditions ◽  
Analytical Dependence ◽  
Load Force ◽  
Physical Parameters ◽  
Technological Equipment ◽  
Waste Landfill ◽  
Relationship Of ◽  
The Relationship

The landfill with technological equipment becomes a clear danger of emergencies. The dangerous factors of emergencies there is landslides of waste mass, explosion of biogas on technological equipment. Modern scientific research aimed at establishing the laws of soil mechanics, obtaining the maximum amount of methane in the biogas composition, an unresolved part of the problem of ensuring civil security is the lack of an adequate method of emergency prevention. In the course of research, by the author was developed a mathematical model of emergency prevention on solid waste landfill with technological equipment. The mathematical model consists of an equation that describes the number of casualties due to an emergency and an equation that describes the existence of solutions to separate problems of estimating the conditions for determining the density, humidity, temperature of the waste mass. The desired solution of a separate problem is an analytical dependence that describes the relationship of the density of the waste mass in accordance with the variation of the physical parameters of the load force, porosity, height of waste storage. The desired solution of a separate problem is an analytical dependence that describes the relationship of the humidity of the waste mass in accordance with the variation of the input and visible fluid flows, density. The desired solution of a separate problem is an analytical dependence that describes the relationship of the temperature of the waste mass in accordance with the variation of the amount of heat supplied, generated, discharged. The number of people affected by an emergency is less than the objective level of the effects of the hazard, and the number of people with impaired living conditions is less than or equal to the objective level. Emergency prevention involves a set of measures aimed at preventing an increase in the number of victims, casualties, and persons with impaired living conditions from an object level to a higher level. Keywords: solid waste landfill, emergency, temperature, humidity, density.

Investigation of the Relationship of Muscle Mechanical Characteristics with Biosignal Energy

2006 ◽  
Vol 113 ◽  
pp. 151-156
Author(s):  
Mečislovas Mariūnas ◽  
Kristina Kojelyte
Keyword(s):  
Mechanical Characteristics ◽  
Extreme Points ◽  
Shift Function ◽  
Energy Equality ◽  
Second Derivatives ◽  
Digital Methods ◽  
Relationship Of ◽  
The Relationship ◽  
Analytical Expressions ◽  
Derivatives Of

Based on biosignal energy equality to the work performed by a muscle, in the estimation of energy dissipation within a biolotronic system, analytical expressions have been derived that have helped to calculate major mechanical characteristics of the muscle including elongation of the muscle, speed and acceleration of such elongation. The paper presents the analysis of relevant digital methods alongside with the formulae for the calculation of major mechanical characteristics when the relationship of a muscle biosignal that is presented in a graphical way. As shown, fatigue of the muscle is characterized by one of extreme points of the phase shift function. The values of the first and the second derivatives of the elongation function may be used for the evaluation of functional capacity of the muscle.

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