Fast feasibility check of the multi-material vertical alignment problem in road design

2019 ◽  
Vol 75 (2) ◽  
pp. 515-536 ◽  
Author(s):  
Dominique Monnet ◽  
Warren Hare ◽  
Yves Lucet
Keyword(s):  
Vertical Alignment ◽  
Road Design ◽  
Alignment Problem

scholarly journals Multi-fidelity algorithms for the horizontal alignment problem in road design

2019 ◽  
Vol 52 (11) ◽  
pp. 1848-1867 ◽  
Author(s):  
Mahdi Aziz ◽  
Warren Hare ◽  
Majid Jaberipour ◽  
Yves Lucet
Keyword(s):  
Horizontal Alignment ◽  
Road Design ◽  
Alignment Problem

scholarly journals S-Shaped Transition Curves as an Element of Reverse Curves in Road Design

2019 ◽  
Vol 14 (4) ◽  
pp. 484-503 ◽  
Author(s):  
Andrzej Kobryń ◽  
Piotr Stachera
Keyword(s):  
Research Topic ◽  
Vertical Alignment ◽  
Geometric Properties ◽  
Road Design ◽  
Geometric Systems ◽  
Practical Usefulness ◽  
Circular Curves ◽  
Traditional Approaches ◽  
Transition Curves

A road designing involves horizontal and vertical alignment. The horizontal geometry is formed by straight and curvilinear sections that are traditionally formed using circular and transition curves (mainly the clothoid). Different geometric systems that are designed using circular and transition curves are between others circular curves with symmetrical or unsymmetrical clothoids, combined curves, oval curves and reverse curves. Designing these systems is quite complex. Therefore, so-called S-shaped transition curves are an alternative to traditional approaches. These curves are known from literature and are modern geometric tools for the shaping of reverse curves. The paper analyses the basic geometric properties of these curves as well as compare to the geometry of the appropriate geometric systems, which are formed with clothoid or using S-shaped transition curves. In addition, a procedure for designing reverse curves using S-shaped transition curves was proposed. Another research topic was the comparison of the analysed reverse curves (created using polynomial transition curves) with traditional curves (created using the clothoid). The results of the studies, despite the noticeable differences in the geometry of the compared components, confirm the practical usefulness of the S-shaped transition curves for designing the geometry of the route.

scholarly journals Perencanaan Geometri Jalan Berdasarkan Metode Bina Marga Menggunakan Program Visual Basic

2011 ◽  
Vol 2 (1) ◽  
pp. 325
Author(s):  
Eduardi Prahara
Keyword(s):  
Highway Construction ◽  
Visual Basic ◽  
Geometric Design ◽  
Vertical Alignment ◽  
Low Speed ◽  
Horizontal Alignment ◽  
The Road ◽  
Road Design ◽  
Manual Calculation

One of the main things in a highway construction plan is the geometric design that includes horizontal and vertical alignment design. This study aims to formulate the steps of highway geometric design into Visual Basic 2005 program. The design steps are the calculation of horizontal and vertical alignment. Using Visual Basic 2005, it is expected that the calculation can be done faster than the manual calculation without mistake. The program is validated by comparing results obtained by manual calculations with a difference about 1x10-4 which is considered accurate. As a case study, a geometric road design is conducted in Bogor in 2009 with a fairly low-speed plan 20-40 km/hour. In the plan, the road has 28 PI (Points of Intersection) on the horizontal alignment and 15 PVI (Point of Vertical Intersection) and obtains good results in accordance with requirements and regulations issued by Bina Marga. 

scholarly journals Minimizing earthwork volumes by optimizing vertical alignment with linear programming algorithm

2020 ◽  
Vol 224 ◽  
pp. 03028
Author(s):  
Aytug Artun ◽  
Vladimir Badenko ◽  
Yulia Volkova ◽  
Anton Radaev
Keyword(s):  
Optimization Model ◽  
Construction Projects ◽  
Linear Optimization ◽  
Road Construction ◽  
Programming Algorithm ◽  
Vertical Alignment ◽  
Volume Calculation ◽  
The Road ◽  
Road Design ◽  
Linear Optimization Model

Earthwork cost is one of the major cost items (approximately 25% of the construction costs) in road construction projects. The amount of earthwork volumes therefore earthwork cost, mostly depends on the geometry of the road vertical alignment. We can conclude that an optimized vertical alignment has a profound impact on earthwork costs. In this research paper, we solve the task connected to the minimization of earthwork cost by optimizing vertical alignment by the development of linear optimization model with different categories of unknown variables including vertical offsets between road and surface in different points as well as extremum points’ numbers. Proposed linear optimization model is supposed to be implemented with application of simplex method as the component of complex branch and bound approach. The developed model has been implemented on the basis of practical example. After the optimization of vertical alignment, earthwork volumes have been calculated in the road design software with average end area volume calculation method. We also have provided numerical results which include earthwork volumes and cost improvements over preliminary design.

Aspects Regarding 3D Road Modeling in Virtual Reality Scenarios for Driving Simulators

2010 ◽  
Vol 166-167 ◽  
pp. 439-444
Author(s):  
Razvan Vlad Vasiu ◽  
Cornel Brisan
Keyword(s):  
Virtual Reality ◽  
Graphical Representation ◽  
Design Parameters ◽  
Geometric Representation ◽  
Vertical Alignment ◽  
Driving Simulators ◽  
The Road ◽  
Road Design ◽  
Safety Regulations ◽  
Selection Of

Road design aims at the selection of geometric design parameters resulting in a road environment which can be used in driving simulators, in accordance with real situations. The following chapters present the road alignment parameters with respect to their geometric representation in virtual reality, focused on two road profiles, horizontal and vertical alignment. This paper discusses and presents the graphical representation of roads in Matlab m-code as virtual reality models with respect to safety regulations.

Influence of Vertical Alignment of Expressway Tunnel on Traffic Safety of Tunnel

CICTP 2020 ◽  
2020 ◽  
Author(s):  
Yifei Zhao ◽  
Jun Wang ◽  
Shunchao Yin ◽  
Jiaqing He ◽  
Zhongyi Chen
Keyword(s):  
Traffic Safety ◽  
Vertical Alignment

Safety at Curves and Road Geometry Standards in Some European Countries

1996 ◽  
Vol 1523 (1) ◽  
pp. 99-106 ◽  
Author(s):  
Thierry Brenac
Keyword(s):  
Urban Areas ◽  
National Standards ◽  
European Countries ◽  
Design Standards ◽  
The Road ◽  
Horizontal Curves ◽  
Road Design ◽  
Road Geometry ◽  
Design Speed ◽  
Curve Geometry

This paper deals with safety at horizontal curves on two-lane roads outside urban areas and the way the road design standards of different European countries account for this safety aspect. After a review of some research results, the main aspects of curve geometry and the curve's place in the horizontal alignment are analyzed. The main conclusions are that the traditional design speed approach is insufficient and that formal complementary rules in road design standards, especially to improve compatibility between successive elements of the alignment, must be introduced. If such complementary rules already exist in some national standards, they are neither frequent nor homogeneous throughout the different countries, and it seems that they are not based on sufficiently developed knowledge.

scholarly journals Integrated Double-Sided Random Microlens Array Used for Laser Beam Homogenization

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 673
Author(s):  
Wei Yuan ◽  
Cheng Xu ◽  
Li Xue ◽  
Hui Pang ◽  
Axiu Cao ◽  
...  
Keyword(s):  
Laser Beam ◽  
Microlens Array ◽  
Energy Utilization ◽  
Utilization Rate ◽  
Periodic Lattice ◽  
Lattice Distribution ◽  
Speckle Field ◽  
High Laser ◽  
Alignment Problem ◽  
In Series

Double microlens arrays (MLAs) in series can be used to divide and superpose laser beam so as to achieve a homogenized spot. However, for laser beam homogenization with high coherence, the periodic lattice distribution in the homogenized spot will be generated due to the periodicity of the traditional MLA, which greatly reduces the uniformity of the homogenized spot. To solve this problem, a monolithic and highly integrated double-sided random microlens array (D-rMLA) is proposed for the purpose of achieving laser beam homogenization. The periodicity of the MLA is disturbed by the closely arranged microlens structures with random apertures. And the random speckle field is achieved to improve the uniformity of the homogenized spot by the superposition of the divided sub-beams. In addition, the double-sided exposure technique is proposed to prepare the rMLA on both sides of the same substrate with high precision alignment to form an integrated D-rMLA structure, which avoids the strict alignment problem in the installation process of traditional discrete MLAs. Then the laser beam homogenization experiments have been carried out by using the prepared D-rMLA structure. The laser beam homogenized spots of different wavelengths have been tested, including the wavelengths of 650 nm (R), 532 nm (G), and 405 nm (B). The experimental results show that the uniformity of the RGB homogenized spots is about 91%, 89%, and 90%. And the energy utilization rate is about 89%, 87%, 86%, respectively. Hence, the prepared structure has high laser beam homogenization ability and energy utilization rate, which is suitable for wide wavelength regime.

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