Longitudinal road unevenness with periodic components: Characterization and effects on people in a traversing vehicle and the loading of the pavement

2005 ◽  
Vol 219 (6) ◽  
pp. 773-790 ◽  
Author(s):  
O Kropáč ◽  
P Múčka
Keyword(s):  
Spectral Density ◽  
Power Spectral Density ◽  
Longitudinal Profile ◽  
International Roughness Index ◽  
Passenger Car ◽  
The Road ◽  
Power Spectral ◽  
Roughness Index ◽  
Pavement Structure ◽  
Periodic Components

Firstly, the effect of periodic components (undulation) appearing in the otherwise random longitudinal profile of road on standard indicators of random unevenness is studied. The power spectral density characterized by its parameters, i.e. the unevenness index and waviness, three band variances, and international roughness index are considered. Secondly, a series of simulation examples is given of the response of two planar vehicle models (a passenger car and a truck) traversing along the road with periodic components of longitudinal unevenness. The effects on people sitting in the vehicle and on the loading of the vehicle undercarriage and pavement structure are studied. The wavelengths of undulation and the running speeds that appear as most inconvenient are emphasized

Relationship between International Roughness Index and Power Spectral Density of Asphalt Pavements in China

2013 ◽  
Vol 742 ◽  
pp. 104-108
Author(s):  
Shao Wen Liu ◽  
Xiao Zhang
Keyword(s):  
Spectral Density ◽  
Power Spectral Density ◽  
Response Function ◽  
Asphalt Pavements ◽  
International Roughness Index ◽  
Quarter Car Model ◽  
Pavement Roughness ◽  
Power Spectral ◽  
Roughness Index ◽  
Quarter Car

In this paper, pavement roughness is assumed as random stationary variable and used as the exciting force of theoretical analyses of the quarter car model of International Roughness Index (IRI). From the frequency response function of the quarter car, the response function of the displacement difference between sprung and unsprung mass is obtained based on random process theory. Then the relationship between IRI and power spectral density (PSD) is established from statement characteristic of the response function. Finally, the longitudinal road profiles of typical asphalt roads in China are used to validate the proposed model.

scholarly journals Evaluation of the methodologies used to generate random pavement profiles based on the power spectral density: An approach based on the International Roughness Index

2017 ◽  
Vol 37 (1) ◽  
pp. 49 ◽  
Author(s):  
Boris Jesús Goenaga ◽  
Luis Guillermo Fuentes Pumarejo ◽  
Otto Andrés Mora Lerma
Keyword(s):  
Spectral Density ◽  
Power Spectral Density ◽  
Pavement Management ◽  
Dynamic Loads ◽  
International Roughness Index ◽  
Vertical Excitation ◽  
Shaping Filter ◽  
Pavement Roughness ◽  
Power Spectral ◽  
Roughness Index

The pavement roughness is the main variable that produces the vertical excitation in vehicles. Pavement profiles are the main determinant of (i) discomfort perception on users and (ii) dynamic loads generated at the tire-pavement interface, hence its evaluation constitutes an essential step on a Pavement Management System. The present document evaluates two specific techniques used to simulate pavement profiles; these are the shaping filter and the sinusoidal approach, both based on the Power Spectral Density. Pavement roughness was evaluated using the International Roughness Index (IRI), which represents the most used index to characterize longitudinal road profiles. Appropriate parameters were defined in the simulation process to obtain pavement profiles with specific ranges of IRI values using both simulation techniques. The results suggest that using a sinusoidal approach one can generate random profiles with IRI values that are representative of different road types, therefore, one could generate a profile for a paved or an unpaved road, representing all the proposed categories defined by ISO 8608 standard. On the other hand, to obtain similar results using the shaping filter approximation a modification in the simulation parameters is necessary. The new proposed values allow one to generate pavement profiles with high levels of roughness, covering a wider range of surface types. Finally, the results of the current investigation could be used to further improve our understanding on the effect of pavement roughness on tire pavement interaction. The evaluated methodologies could be used to generate random profiles with specific levels of roughness to assess its effect on dynamic loads generated at the tire-pavement interface and user’s perception of road condition.

scholarly journals Vehicle response on kinematic excitation

2018 ◽  
Vol 211 ◽  
pp. 13001
Author(s):  
Veronika Valašková ◽  
Jozef Melcer
Keyword(s):  
Spectral Density ◽  
Frequency Domain ◽  
Power Spectral Density ◽  
Engineering Problem ◽  
Kinematic Excitation ◽  
The Road ◽  
Power Spectral ◽  
Road Profile ◽  
Vehicle Response ◽  
On The Road

The vehicle - roadway interaction is actual engineering problem solved on many workplaces in the world. At the present time preference is given to numerical and experimental approaches. Vehicle designers are interested in the vibration of the vehicle and the forces acting on the vehicle. Civil engineers are interested in the load acting on the road. Solution of the problem can be carried out in time or in frequency domain. Road unevenness is the main source of kinematic excitation of the vehicle and therefore the main source of dynamic forces acting both on the road and the vehicle. The offered article deals with one of the possibilities of numerical analysis of the vehicle response in frequency domain. It works with quarter model of the vehicle. For the selected computational model of the vehicle it quantifies the Frequency Response Functions (FRF) of both force and kinematic quantities. It considers the stochastic road profile. The Power Spectral Density (PSD) of the road profile is used as input value for the calculation of Power Spectral Density of the response. All calculations are carried out numerically in the environment of program system MATLAB. When we know the modules of FRF or the Power Response Factors (PRF) of vehicle model the calculation of vehicle response in frequency domain is fast and efficient.

scholarly journals Simulation of Pavement Random Excitation Based on Harmonic Superposition Method

2021 ◽  
Vol 2 (3) ◽  
Author(s):  
Kehui Ma ◽  
Yongguo Zhang ◽  
Xü Zhen
Keyword(s):  
Spectral Density ◽  
Power Spectral Density ◽  
Ride Comfort ◽  
Random Excitation ◽  
Superposition Method ◽  
Generation Model ◽  
The Road ◽  
Power Spectral ◽  
Control Research ◽  
The Relationship

The road input model is very important in the analysis of vehicle ride comfort and handling stability. Based on the analysis of the relationship between the spatial frequency power spectral density and the time power spectral density of the road, the road signal generation model is established. The simulation is carried out under different vehicle speeds, and the B and C-level random road time excitation signals are generated. The power spectral density is used to compare the simulation results of the model with the road classification standard. The experimental results show that the results are accurate and can provide reliable excitation signals for vehicle control research.

Vibration Measurement and Spectral Analysis of Chassis Frame Mounted Structure for Off-Road Wheeled Heavy Vehicles

2016 ◽  
Vol 8 (1) ◽  
Author(s):  
V.R. Deulgaonkar
Keyword(s):  
Spectral Analysis ◽  
Spectral Density ◽  
Power Spectral Density ◽  
Dominant Frequency ◽  
Vibration Measurement ◽  
Road Transportation ◽  
The Road ◽  
Power Spectral ◽  
Cross Country ◽  
Paved Road

Chassis mounted structure is a base component for shelters or containers mounted on heavy transport vehicles. When the vehicle is driven in rough terrains or during off-road transportation this structure has a significant role in protecting the sophisticated cargo and intelligent tracking systems placed inside the shelters. During off-road transportation or warhead conditions the vehicle is subjected to large unevenness in load due to road or soil irregularities in rough terrains, which causes vibrations to be induced in the vehicle. As the nature of vibrations induced in vehicle during travel on off-road or cross-country terrains is random and unpredictable, there is a concern to analyse the vibration response of chassis and chassis mounted structures is needed. Present work deals with vibration measurement and spectral analysis of a chassis mounted structure designed for off-road and commercial transport vehicles. The road profile on which the vibration measurement has been carried out includes paved road and cross-country terrain segments. The vibration measurement has been carried at three different vehicle speeds. Signal analysis procedure for the acquired test data is discussed. The chassis mounted structure under concern is intended to hold two shelters or containers. From the vibration measurement at critical locations, g-(RMS) and g-(peak) values for paved and cross-country roads have been found out. Power spectral density values have also been found on chassis and structure for the same transport situations. Major inferences include the evaluation of minimum and maximum g-values (peak and RMS) on chassis and chassis mounted structure. Power spectral density graphs are constructed from which the dominant frequency for both road profiles is found out.

scholarly journals Vehicle model response in frequency domain

2020 ◽  
Vol 313 ◽  
pp. 00009
Author(s):  
Jozef Melcer ◽  
Veronika Valašková
Keyword(s):  
Spectral Density ◽  
Frequency Domain ◽  
Power Spectral Density ◽  
Vehicle Model ◽  
Response Factors ◽  
The Road ◽  
Power Spectral ◽  
Road Profile ◽  
Model Response ◽  
Vehicle Response

The offered article deals with one of the possibilities of numerical analysis of the vehicle response in frequency domain. It works with quarter model of vehicle. For the selected computational model of vehicle it quantifies the Frequency Response Functions (FRF) of both force and kinematic quantities. It considers the stochastic road profile. The Power Spectral Density (PSD) of the road profile is used as input value for the calculation of Power Spectral Density of the response. Al calculations are carried out numerically in the environment of program system MATLAB. When we know the modules of FRF or the Power Response Factors (PRF) of vehicle model the calculation of vehicle response in frequency domain is fast and efficient.

Alternative single-number indicator of longitudinal road unevenness

2009 ◽  
Vol 36 (3) ◽  
pp. 389-401 ◽  
Author(s):  
Oldřich Kropáč ◽  
Peter Múčka
Keyword(s):  
Subjective Rating ◽  
Vehicle Speed ◽  
International Roughness Index ◽  
The Road ◽  
Full Characterization ◽  
Power Spectral ◽  
Roughness Index ◽  
On The Road ◽  
Single Number

For the full characterization of the longitudinal road unevenness based on the road elevation power spectral density (PSD), at least two independent indicators are necessary: the unevenness index and the waviness. Yet, for road management purposes, single-number unevenness indicators are still required and a number of such indicators have been proposed to date. The main problem of this issue consists in an adequate combination of the two mentioned indicators to obtain a single indicator whose application would fulfil the requirements, which are sometimes contradictory. The importance of the interaction coupling between the road and the travelling vehicle, in which the vehicle speed also plays a significant role, is emphasized. An alternative single-number indicator is proposed based on the equivalent vibration response effect, which the uneven road causes on the traversing vehicle. Other approaches to this problem are briefly discussed using comparative examples, including the indirect approach, a proposal for the modification of the international roughness index (IRI), and an assessment of the subjective rating methods.

Sign in / Sign up

Export Citation Format

Share Document