New Results from Full-Scale Vehicle-Pavement System Experiments on a Circular Test Track

The paper deals with some new results obtained during a two-year research activity on a circular track, which was built in Czechoslovakia for testing the serviceability of different structural types of carriageways. During the testing process the influence on the growing dynamic response of three loading vehicles was also registered, so that experimental verification of the internal dynamic effects in the undercarriage system of loading vehicles according to the Czechoslovak hypothesis of the physical invariant dynamics could be obtained. This contribution presents the basic principles of the invariant theory. Very good agreement of the theoretical calculations with the experimental results on a typical two-mass dynamic system can be stated. For the prediction of serviceability of road pavements an empiricial relation has been derived based on statistical date obtained during a nearly one-year testing period.     

Gender,Residential Location,and Household Travel: Empirical Findings from Low‐income Urban Settlements in Durban,South Africa

Abstract

Urban development and transport policies designed to improve the livelihoods of poor communities need to consider the particular needs of women to be effective. Gender roles are played out in a spatial world, and can thus be expected to vary across the urban landscape. The paper examines empirical relationships between spatial factors—in particular residential location within the city—and travel behaviour for men and women in a cross‐section of low‐income communities in a large metropolitan area in South Africa. Data from a comprehensive household survey show that locality has a significant influence on gender experiences of mobility. Gender differences are greatest in more distant, rural localities, although site‐specific characteristics such as walking access to social services, informal work, and small‐scale agriculture help alleviate women’s inequitable travel burdens. Central localities display the smallest differences between men and women’s travel habits, supporting the notion that the high access afforded by centrally located housing helps to promote the satisfaction of women’s daily needs as well as their strategic empowerment. Households in peri‐urban and peripheral localities suffer the highest travel burdens, having neither the high access of a central location nor the livelihoods‐enhancing amenities of a rural environment. Women bear a large part of this burden. Urban development strategies to benefit the urban poor while promoting gender equity are highlighted, including an added emphasis on the provision of social and educational infrastructure within closer proximity to peripheral residential areas, coupled with better pedestrian access.     

Characterization of Longitudinal Road Unevenness in the Light of the International PIARC - EVEN Experiment 1998

The basic model of road pavement unevenness (homogeneous random function with Gaussian distribution function and simple power spectral density function) is generalized to cover real states of roads under traffic conditions, such as: independent characterization of long and short wavelengths unevenness, and consideration of non-homogeneity including appearance of individual large imperfections. The method of estimating relevant parameters is based on the interaction coupling between the traveling vehicle and the road. To justify the need for these generalizations, summarizing results are given of the International PIARC - EVEN experiment conducted in 1998 in three world regions (Arizona, USA, Hokkaido, Japan, and Netherlands / Germany). Total 47 road sections of different technological execution and different unevenness levels were tested using DYNVIA device.