Highway Design Consistency: Refining the State of Knowledge and Practice

Author(s):  
Yasser Hassan
Author(s):  
Yevhenij Іmas ◽  
Olena Lazarieva

Topicality. The crisis situation of the state of Ukrainian population health lifts the level of rehabilitation of patients and persons with disability to the priority national problem. The state of rehabilitation services grant substantially depends on the skilled personnel providing. Research aim: on the basis of analysis of scientifically-methodical literature and normatively legal acts to investigate pre-conditions and modern trends of progress of physical therapy and occupational therapy specialities in Ukraine. Research results. The educational programs of specialists preparation on a physical rehabilitation have many defects, and preparation of specialists on occupational therapy is absent in our country absolutely. In accordance with normative acts physical therapy is the legal successor of physical rehabilitation in our country, but these concepts are not identical. The intensive process of forming of new specialities, criterias of accreditation, educational programs of retraining passes in Ukraine. Conclusions. Change of legal bases in the sphere of preparation and labour of physical therapeutists and ergotherapeutists, design of educational programs in accordance with international standards, is the first step on a way to quality development of these fields of knowledge and practice.


2007 ◽  
Vol 34 (9) ◽  
pp. 1159-1168 ◽  
Author(s):  
Said M Easa ◽  
Atif Mehmood

Highway design consistency is one of the important criteria in selecting the geometric features of proposed or existing alignments of two-lane rural highways. Operating-speed (OS) profile models have been used to evaluate design consistency by trial and error. For a proposed new highway, however, there may be geometric and physical constraints, and selection of these elements by trial and error to achieve optimal design consistency would be difficult, if not impossible. This paper presents an optimization model that establishes highway horizontal alignment to achieve maximum design consistency based on the OS profile. The decision variables of the model include radius of horizontal curves, spiral curve lengths, length of speed-change (SC) segments, and acceleration and deceleration rates. The objective function of the model minimizes the mean OS difference or the maximum OS difference for successive geometric features along the highway section. Application examples and sensitivity analysis are presented to illustrate the capabilities of the model in evaluating improvement strategies and to ensure that the model produces sound optimum alignments. The proposed model, which complements existing optimization models that mainly address highway construction cost, should be of interest to highway practitioners and engineers.Key words: design consistency, highway, geometric, horizontal alignment, optimization modeling, speed profile.


The Texas State Department of Highways and Public Transportation (SDHPT), Highway Design Division, in cooperation with the Office of the State Governor, The Office of the State Historic Preservation Officer, and the City of Laredo, has recently investigated the approach roadway and the bridge site of the proposed Colombia-Laredo International Bridge across the Rio Grande, in Webb County, Texas. The work was conducted to identify cultural resources in these areas and to offer a preliminary description and evaluation of historic properties considered to be potentially eligible to the National Register of Historic Places. One historical archaeological locale, 41WB205 (portions of the early 20th century mining community of Darwin) and one prehistoric terrace occupation zone, 41WB206, were investigated. Although the portion of 41WB205 within the projected roadway has been severely impacted by modern alteration, the larger and less disturbed surrounding site area is considered to be potentially eligible for the National Register.


2021 ◽  
Author(s):  
Yingfeng Li

The mission of transportation is to transport people and goods safely and efficiently. Therefore, traffic safety has been one of the most important topics since the birth of the subject of transportation. Improving highway design consistency is considered as an important strategy for improving traffic safety. Geographic information systems (GIS) has been popular for decades due to its great ability to deal with spatial or spatially-related data. Contributions from GIS to transportation have become well known in some aspects. However, GIS, especially its 3D visualization function, has not, in previous studies, been integrated into the core of the highway design consistency evaluation procedure. In contrast, the major objective of this thesis research is to integrate the latest advanced GIS techniques including its 3D visualization function and the state-of-the-art knowledge from previous studies into the highway design consistency evaluation procedure. By adding new functions specifically developed for highway design consistency evaluation, a 3D GIS-based highway design consistency evaluation methodology is developed. This newly developed methodology and associated software tools, as a combination of GIS, including its 3D visualization function, and highway consistency modules, will make significant contributions in the following aspects: highly automated consistency evaluation procedure, 3D-alignment-based consistency level analysis, impressive evaluation result presentation, and spatially based consistency improvement suggestion. Verification of this methodology on a typical 3D-highway segment in Ontario shows very promising results. This study, to a great extent, is convincing that, in the near future, designers could be able to design highways in a regular GIS environment.


2021 ◽  
Author(s):  
Lisa Kadoury

This research focuses on evaluating driver visual demand at different traffic volumes along with geometric design features for two-dimensional (2D) multi-lane highways consisting of horizontal and vertical alignments which is a crucial part of highway design consistency research. Three such alignments, with simple and complex curves were designed to generate desired traffic volume levels. A driving simulator was used to collect date from twenty drivers that participated in roadway alignment experiments at Ryerson University. Statistical Analysis Software (SAS) was used to analyze and process output data. Models were developed for visual demand and volume/capacity ratios, and geometric characteristics of the road, where visual demand was the only dependent variable. The research found that a relationship exists between visual demand and different traffic volumes along with geometric characteristics of the road.


2021 ◽  
Author(s):  
Lisa Kadoury

This research focuses on evaluating driver visual demand at different traffic volumes along with geometric design features for two-dimensional (2D) multi-lane highways consisting of horizontal and vertical alignments which is a crucial part of highway design consistency research. Three such alignments, with simple and complex curves were designed to generate desired traffic volume levels. A driving simulator was used to collect date from twenty drivers that participated in roadway alignment experiments at Ryerson University. Statistical Analysis Software (SAS) was used to analyze and process output data. Models were developed for visual demand and volume/capacity ratios, and geometric characteristics of the road, where visual demand was the only dependent variable. The research found that a relationship exists between visual demand and different traffic volumes along with geometric characteristics of the road.


Author(s):  
Alfonso Montella ◽  
Francesco Galante ◽  
Filomena Mauriello ◽  
Massimo Aria

To improve highway design consistency, several studies developed operating speed prediction models and investigated drivers' speed behavior. Most existing models are based on spot speed data that assume constant operating speed throughout the horizontal curves and occurrence of acceleration and deceleration only on tangents. To overcome limitations associated with existing models, this study investigated continuous speed profiles with an experiment that used a high-fidelity dynamic-driving simulator on a two-lane highway. A piecewise linear regression model and locally weighted regression scatter-plot smoothing were used to remove noise in the data set while preserving underlying patterns and to identify significant changes in the speed profile. Based on the smoothed speed profiles, models to predict operating speed in curves and in tangents, deceleration and acceleration rates to be used in the operating speed profiles, and starting and ending points of constant operating speed in curve were developed. Radius of the curve notably affected not only the operating speed in the curve but also the operating speed of the tangent following the curve: the smaller the radius, the lower the operating speed of the exit tangent. Both acceleration and deceleration rates increased with curvature. This study found that operating speed was not constant along curves. On small radius curves, deceleration ended close to the center of the curve, and acceleration starts, close to the end of the curve. Increasing the curve radius, the end point of deceleration moves toward the curve's beginning, whereas the start of acceleration moves toward the center of the curve.


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