Road Design

A theoretically based base course thickness design method for unpaved roads was developed in the companion paper. This paper presents a calibration of the design method using data from field wheel load tests and laboratory cyclic plate loading tests on unreinforced and reinforced base courses. The constants in the design method are determined during the calibration. The calibrated design method is used for analyzing the test data through three case studies. In addition, the design procedures and a design example are provided in this paper to demonstrate the use of the design method. . Based on the discussions in the companion paper, the bearing capacity factor should be used: N c ϭ3.14 for unreinforced unpaved roads, N c ϭ5.14 for geotextile-reinforced unpaved roads, and N c ϭ5.71 for geogrid-reinforced unpaved roads.

This report gives an insight on "Road Condition Survey"- with detailed description on how it is performed. It also discusses the requirements of a road condition survey, when and why it is required and in which cases. It gives an idea of when a road condition survey is required and how it can be performed so as to ensure a smooth traffic- flow.

**A new version 6.2 has recently been added to Academia**. A country-by-country listing of road design standards and similar documents. The document is a work in progress, and all versions are beta version. This version 6.1, "Ghaha edition", was prepared in August 2016 and contains notes on 79 countries, 7 multi-country standards and 3 special topics. Total 128 pages, file size about 1.2 MB. Total views on Academia for previous version were 795.

It is a crucial task to reduce road crashes by performing analyses and taking appropriate countermeasures to save lives. It has been a major issue for many people and government to reduce the amount of road collisions especially in Iran, since it could be a great threat to this country. Identification of crash black-sites is one of the most important fields in road safety studies. Many highway agencies have been using Geographical Information System (GIS) for analyzing crash data. The GIS based application integrates the information collection capabilities with the visualization. In this paper, Incident features like location, date, type of vehicle involved, and number of persons injured or died are imported in the GIS database. Then, Kernel density is to apply on the prepared data. The main objective is to specify road crash black-spots considering all types of traffic crashes based on their severity using Kernel Density through GIS environment. The results show that more severe crashes take place further from the cities than accidents with only property damages. Also, overlaying all crash types using the suggested SI (severity index) method will generate crash black-sites map which policy makers can use to determine accident-prone zones and take appropriate interventions.

This paper evaluates issues connected with vehicular movement moving through various urban road systems. As a consequence of the constant increment of activity in focal urban regions, movement lines and defers are knowledgeable about the region of crossing points. Fast incremental improvement, increase in urban range and development in vehicular movement has come about into issues of clog, contamination and over usage of accessible limit coming about into increase in travel time and diminishment of limit because of expanding clashes made by expanded stream of activity. Subsequently, need of this study is feel to perform similar investigation of the stream under circumstance where the clashing circumstance can be minimized. Study reveals that such minimization of conflicts and segregation of traffic is possible by proper channelization. Present signalized intersection is evaluated by traffic analysis and suitable design parameters of rotary intersection are developed to give safer, high capacity and more reliable movement at intersection.

Population increment has changed many aspects of human livelihoods, congested cities, rural areas with
less facilities than city limits. Roads have been developed to connect city areas and rural areas to transport
primary production and value-added products to city areas, transport human labor to the city limits etc.
Concrete lined roadside drainage canals have been used to carry surface runoff. Further to those human
settlements have wide spreads across all most all ecosystems and spread was identified as low-density
expansion in rural areas and sprawl expansion in semi urban and urban areas creating connected and not
connected impervious areas creating devastating ecological impacts.
Impervious areas generate huge amount of overland flow and roadside drainage canals are used to
evacuate those runoff waters as quickly as possible to minimize flood threats and therefore, reducing the
infiltration. Long term evacuation of these flood waters may cause serious impacts over groundwater
replenishment.
This scenario may be well pronounced in hilly areas where slopy lands having impervious areas may
generate overland flows with higher flow velocities than flat land areas. Hence, there is a potential of
running overland flow via roads and evacuation is quicker than flat lands. This situation may cause
depletion of groundwater reserves with time.
Therefore, there is a need to quantify the amount of overland flow runs through roads and roadside
drainage lines towards drainage outlets. Present paper discusses a simple method to quantify the runoff
volume runs through roads and roadside drainage canals.

 To learn to apply a system approach to a plan, execute and manage a survey given specification as a group  To learn and undertake site measurements and calculations using proper equations  To learn how to analyze data with respect to error theory and produce scale plots  To learn how to work in a team  Read information from maps and plans  To learn how to use the survey equipment such as total stations and auto level  To learn how to interpret the data obtained and how to use the spread sheets to reduce, adjust and analyze the data According to J. Uren's and W.F.Price's book, Surveying for Engineers, they describe surveying as an art of determining the relative positions of different object on the surface of the earth by measuring the horizontal distance between them and by preparing a map to any suitable scale.

The quality of roads as public goods should be maintained and improved time to time. In order to put the available funds on the right roads for the optimal results, roads should be prioritized. This paper discussed how prioritization on road maintenance. The materials and method used are based on literature review. Discussion starts with the definition of local roads, the role of local road maintenance, and the definition of local road maintenance. The second part discuss the definition of prioritization, the objective of prioritization, and the roles of prioritization in road maintenance. The third part examines the common prioritization procedures conducted in planning process reflecting prioritization methods used in road maintenance prioritization. The fouth part discuss ciriteria in ranking alternatives which are single and multi criteria. The fifth part discuss the definition of actors, the roles of actors involved, the actors' attributes, and the types of actors in road maintenance prioritization process. According to the literature, there are four groups of prioritization methods based on procedure they conducted, and there are eight types of actors involved in prioritization process determined by the attributes such as power, legitimacy, and urgency they possess. The choice of method depends on where the roads to be prioritized are located.

This report gives an insight on Spot Speed, why it is required and the methodology by which spot speed studies can be performed. It also discusses how spot speed studies can help to design better roads in order to ensure smooth traffic- flow.

Intersections are critical places which experience high levels of accidents due to the availability of vehicle movements from different directions. Therefore, there is a need to understand the factors that significantly contribute to injuries at such places. These factors can fall under different dimensions in traffic safety such as environmental conditions, road user behavior, traffic police enforcement, road design and crash characteristics. The paper will analyze the factors related to crash characteristics and traffic signal operation that affect the likelihood of accident severity located at intersections. The data for intersection accidents in Abu Dhabi from 2013 to 2016 were used in this analysis. Ordinal logistic model was considered for the analysis to account for the ordinal nature of severity levels. Several diagnostics tests of the model were preformed such as parameters evaluation, overall model evaluation and prediction accuracy. For parameter evaluation, out of 11 independent variables, 6 were non-significant and dropped from the model. Most of the non-significant variables were related to the driver-at-fault details. The results of the final model showed an overall good fit based on a p-value of less than 0.05, as well as a good accuracy of prediction 84.8%. Finally, odds ratios were estimated to interpret the final results of the model.

A theoretically based design method for the thickness of the base course of unpaved roads is developed in this paper, which considers distribution of stress, strength of base course material, interlock between geosynthetic and base course material, and geosynthetic stiffness in addition to the conditions considered in earlier methods: traffic volume, wheel loads, tire pressure, subgrade strength, rut depth, and influence of the presence of a reinforcing geosynthetic ͑geotextile or geogrid͒ on the failure mode of the unpaved road or area. In this method, the required base course thickness for a reinforced unpaved road is calculated using a unique equation, whereas more than one equation was needed with earlier methods. This design method was developed for geogrid-reinforced unpaved roads. However, it can be used for geotextile-reinforced unpaved roads and for unreinforced roads with appropriate values of relevant parameters. The calibration of this design method using data from field wheel load tests and laboratory cyclic plate loading tests on unreinforced and reinforced base courses is presented in the companion paper by the authors.

A theoretically based design method for the thickness of the base course of unpaved roads is developed in this paper, which considers distribution of stress, strength of base course material, interlock between geosynthetic and base course material, and geosynthetic stiffness in addition to the conditions considered in earlier methods: traffic volume, wheel loads, tire pressure, subgrade strength, rut depth, and influence of the presence of a reinforcing geosynthetic ͑geotextile or geogrid͒ on the failure mode of the unpaved road or area. In this method, the required base course thickness for a reinforced unpaved road is calculated using a unique equation, whereas more than one equation was needed with earlier methods. This design method was developed for geogrid-reinforced unpaved roads. However, it can be used for geotextile-reinforced unpaved roads and for unreinforced roads with appropriate values of relevant parameters. The calibration of this design method using data from field wheel load tests and laboratory cyclic plate loading tests on unreinforced and reinforced base courses is presented in the companion paper by the authors.

This project aims to evaluate the effectiveness of the quality measures employed by the Wisconsin Department of Transportation to influence the in-service performance of flexible pavements. The study involved creating a relational geo-referenced database connecting production, placement, and routine in-service performance data collected over the years for Wisconsin Projects. The database relied on geo-referencing all the data such that each individual data point is assigned a location. This approach allows for tracking the quality of the material and construction of specific segments of the roadway to the in-service performance. A subset of the projects was also included in an in-depth study using on-site distress survey and non-destructive testing using Falling Wheel Deflectometer (FWD). In general, the thirty (30) highway projects studied in this project show that transverse and longitudinal cracking are the most common distresses. Construction joint longitudinal cracking appears to be highly common in all the on-site visits. Rutting is localized but not common. Alligator cracking takes place in multiple locations. This distress appears to relate to either soft foundation or some of the quality measures.
Deviations from the quality indicators’ targets show correlations with the distresses. Mix production air voids (Va), mix voids in mineral aggregate (VMA), and placement density (%Gmm) are correlated with in-service performance. Deviation from target Va by reduction of 0.25% or more, correlates with a reduction in performance. Accomplishing VMA higher than the target is associated with lower levels of distresses. For %Gmm, about 2% increase in the compacted density show improved performance for thicker than 2” lifts. Thin lifts are more sensitive to the increase in compaction effort than thicker pavements.

Veliki prostor i posebnu pažnju posvetio sam poglavlju “Geloški procesi u zemljinoj kori i na površini“, posebno delu egzodimanički procesi i pojave - površinsko raspadanje (trošenje stena), koje me je najviše „mučilo i kalilo“ kao izvođača građevinskih radova.

Ovaj pisani material, koji sam veoma dugo pisao i proveravao u vrlo bogatoj i veoma teškoj i napornoj građevinskoj praksi, poklon je svim korisnicima koji žele da, u skraćenom obliku (bez velike matematike), dobiju brze i praktične informacije prilikom neke “nejasne” tehničke dileme.

Material je realizovan i zbog nekih, na sreću, ne kardinalnih grešaka u mom dugogodišnjem radu na terenu.

Posebnu zahvalnost dugujem porodici od koje sam bio vrlo dugo “odsutan” iako sam bio tu, u radnoj sobi, na nekoliko metara ali zaokupljen pisanjem ovog materijala.

S poštovanjem, mr Mirko Stanković, dipl. inž., Beograd, generala Štefanika 20/17,
mirsta@eunet.rs  tel:+381 1163-281-371 (063/281-371)

This report gives an insight to road way intersections. It also discusses some of the common problems that often occur due to improper design and placement of roadway intersections. It also briefly discusses some potential solutions that may help reduce the problems at roadway intersection to ensure a smoother traffic- flow through intersections.

A country-by-country listing of road design standards and similar documents. The document is a work in progress, and all versions are beta version. This version 6.2 was prepared in August 2017 and contains notes on 86 countries, 7 multi-country standards and 3 special topics. It is an intermediate update. Total 141 pages, file size about 29 MB. Total views on Academia for previous versions were 2036.

This project aims to evaluate the effectiveness of the quality measures employed by the Wisconsin Department of Transportation to influence the in-service performance of flexible pavements. The study involved creating a relational geo-referenced database connecting production, placement, and routine in-service performance data collected over the years for Wisconsin Projects. The database relied on geo-referencing all the data such that each individual data point is assigned a location. This approach allows for tracking the quality of the material and construction of specific segments of the roadway to the in-service performance. A subset of the projects was also included in an in-depth study using on-site distress survey and non-destructive testing using Falling Wheel Deflectometer (FWD). In general, the thirty (30) highway projects studied in this project show that transverse and longitudinal cracking are the most common distresses. Construction joint longitudinal cracking appears to be highly common in all the on-site visits. Rutting is localized but not common. Alligator cracking takes place in multiple locations. This distress appears to relate to either soft foundation or some of the quality measures. Deviations from the quality indicators' targets show correlations with the distresses. Mix production air voids (Va), mix voids in mineral aggregate (VMA), and placement density (%Gmm) are correlated with in-service performance. Deviation from target Va by reduction of 0.25% or more, correlates with a reduction in performance. Accomplishing VMA higher than the target is associated with lower levels of distresses. For %Gmm, about 2% increase in the compacted density show improved performance for thicker than 2" lifts. Thin lifts are more sensitive to increase in compaction effort than thicker pavements.

► A kind of Elastic Composite, Reinforced Lightweight Concrete (ECRL.C) with the mentioned specifics is a type of "Resilient Composite Systems (RCS)" in which, contrary to the basic geometrical assumption of the flexure theory in Solid Mechanics, "the strain changes in the beam height during bending" is typically "Nonlinear". (The RCS could be counted as "The Methodically Reinforced Nonlinear Porous Materials", also having the high specific modulus of resilience in flexure.)

♦ Through employing this integrated structure, with significantly high strain capability and modulus of resilience in bending, we can achieve the high bearing capacities in beams with the secure fracture pattern, in less weight.

♦ Due to the system particulars and its behavior in bending, the usual calculation of the necessary equilibrium steel amount to attain the low-steel bending sections with the secure fracture pattern in the beams and its related limitations do not become propounded. Thereby, the strategic deadlock of the high possibility of the brittle fracture pattern in the bending elements made of the usual reinforced lightweight concretes, especially about the low-thickness bending elements as slabs, is unlocked.

♦ This simple, applied technology and the related components and systems can have several applications in the road and building industries. (It can also be used in making the resilient pieces and constructions "with appropriate behavior and high resistance against severe blasts and shocks.)

♦ Regarding the "strategic importance of Lightweight and Integrated Construction in the practical increase of the resistance and safety against earthquake" and considering the appropriate behavior of this "resilient", durable structure against the dynamic loads, shakes, impacts, blasts, and shocks and the possibility of making some lightweight and insulating, non-brittle, reinforced sandwich panels and pieces, this resilient system and its components can especially be useful in the "seismic areas".

♦ This system can also be employed in constructing the vibration and impact absorber bearing pieces & slabs, which can be used in the "Railroad & Subway Structures" too.

♦ Here, the "Resilient Composite Systems (RCS)" and particularly, the ECRLC as a type of the RCS have been concisely presented. [By the way, an instance of the said new structure and its components and the results of some performed experiments (as bending loading and compressive loading of the slabs made of this structure, similar to ASTM E 72 Standard) have been shown in the related pictures & figures.]
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/ ● Key Words: Strength of materials (solid mechanics), Civil (construction), Materials, Earthquake (resistance and safety), Resilient concrete (flexible concrete, bendable concrete, elastic concrete), Composite concrete, Lightweight concrete, Reinforced concrete, Fibered concrete, Lightweight and integrated construction, Rail (railroad, railway), Subway, Road, Bridge, Resilience, Energy absorption, Fracture pattern, Non-linear, Strain changes, Beam, Ductility, Toughness, Insulating (insulation), Thin, Slab, Roof, Ceiling, Wall (partition), Building, Tower, Plan of mixture, Insulating reinforced lightweight pieces, 3d, Sandwich panel, Dry mix, Plaster, Foam, Expanded polystyrene (EPS), Polypropylene, Pozzolan, Porous matrix (Pored matrix), Mesh (lattice), Cement, RCS, ECRLC
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/ ► Contents:
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* ABSTRACT
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* I. INTRODUCTION
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* II. WHAT ARE THE RESILIENT COMPOSITE SYSTEMS
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- A. General Review
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- B. Components
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. - 1) Mesh or Lattice
. - 2) Fibers or Strands
. - 3) "Matrix" With the Suitable Hollow "Pores (Voids)" and/or "Lightweight Aggregates" in its Context
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- C. More Explanations About the RCS
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- D. Why Are These Systems Called "Composite"?
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- E. The General Structural Particulars and Functional Criteria as the Necessary Specifications of the Compound Materials Generally Called "Resilient Composite Systems"
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. - 1) General Structural Criteria
. - 2) Functional Criteria (Required Specifications)
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* III. "ELASTIC COMPOSITE REINFORCED LIGHTWEIGHT CONCRETE (ECRLC)" AS A TYPE OF THE RESILIENT COMPOSITE SYSTEMS (RCS)
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- An Instance of the Lightweight Concrete That Could be Used in Making the ECRLC
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* IV. REVIEW OF SOME EXPERIMENTS, AND MORE DESCRIPTION ABOUT ECRLC
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* V. SUPPLEMENTARY ELEMENTS
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* VI. APPLICATIONS
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* VII. FINAL REVIEW
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* ACKNOWLEDGEMENTS
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* REFERENCES 
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***
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/ ● General Review:
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• A kind of "Elastic Composite, Reinforced Lightweight Concrete" with the said specifics is a type of the "Resilient Composite Systems (R.C.S.)" in which, contrary to the basic geometrical assumption of flexure theory in the Solid Mechanics, the strain changes in the beam height during bending is typically "Non-linear".
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• Indeed, the RCS, as the Elastic Composite, Reinforced Lightweight Concrete (ECRLC), do not behave as most of the solid materials in bending.
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• In the "Resilient Composite Systems", distributed pores and/or appropriate lightweight aggregates or beads, accompanied by the reticular structure of the strengthened conjoined matrix, bring about the expedient internal shape changes during bending and continuing the elasticity in bending with the said nonlinearly pattern. This means better distribution of the stresses and strains and better utilizing the potential capacities of the employed reinforcements in bending and tension; whereas, in the usual lightweight concretes for instance, distributed hollow pores (such as the gas bulbs in the cellular concretes) or lightweight aggregates (such as Plastic, Rubber or polystyrene beads or any other kind of lightweight aggregates such as Perlite and Vermiculite) decrease the modulus of resilience in bending and could increase "the possibility of beam fracture of brittle and primary compressive type" in bending (compared to the concrete with higher density) according to the case.
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• In this way, by using the mentioned method to make the said particular composite systems, we could considerably increase the modulus of resilience and bearing capacity in bending "together with" significant decrease of the weight and also the possibility of beam fracture of primary compressive type. Through making these particular integrated functioning systems, for the first time, the said (paradoxical) properties have been concomitantly fulfilled in "one functioning unit" altogether.
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• Respect to the special pattern of the strain changes during bending in the particular Resilient Composite System termed ECRLC, this system as an integrated functioning unit with the reticular arrangement and texture has more strain capability (particularly within the elastic limit), energy absorption and load bearing capacities in bending compared to the usual reinforced concrete beams.
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• Thereby, through employing this applied structure, solving some of the main problems in lightweight concretes application, especially the deadlock of brittle and insecure being of fracture pattern in many of the usual reinforced lightweight concrete structures, is provided; reaching to the high bearing capacities in bending elements (even with low dimensions & weights) is to hand, and getting access to a simple and practical opportunity for "qualitative development of possibilities of using lightweight concretes" (especially with oven-dry densities of < 1350-1400kg/m3 and compressive strengths of <14-17mpa, and even with oven-dry densities of < 800kg/m3) is conceivable.
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• Naturally, by more studies in the field, these structures and their applications in various fields could be developed more.
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***
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/ ► FULL TEXT (Open Access):
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- http://arxiv.org/abs/1510.03933 
( https://arxiv.org/ftp/arxiv/papers/1510/1510.03933.pdf ) ;
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. Kamyar Esmaeili: "Elastic Composite Reinforced Lightweight Concrete as a Type of Resilient Composite Systems";
The Internet Journal of Innovative Technology and Creative Engineering (IJITCE); 2012; 2(8): 1-22.
- http://ia800305.us.archive.org/34/items/IJITCE/vol2no801.pdf [Also archived at: http://www.webcitation.org/6B2pFPpBh ] ;
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- https://www.scribd.com/doc/11530978/Elastic-Composite-Reinforced-Lightweight-Concrete-ECRLC-as-a-type-of-Resilient-Composite-Systems-RCS-http-arxiv-org-abs-1510-03933 ; 
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- https://sites.google.com/site/NEWSTRUCTURE1 ;
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- https://sites.google.com/site/newstructure1/publications-page/ELASTIC%20COMPOSITE%2C%20REINFORCED%20LIGHTWEIGHT%20CONCRETE%20AS%20A%20TYPE%20OF%20RESILIENT%20COMPOSITE%20SYSTEMS.pdf ;
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- http://www.pdf-archive.com/2015/09/22/elasticcomposite-reinforcedlightweightconcreteasatypeofrcs/elasticcomposite-reinforcedlightweightconcreteasatypeofrcs.pdf ;
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- The link to the document in PDF format on this site:
file:///C:/Users/pc5/Downloads/ELASTIC_COMPOSITE_REINFORCED_LIGHTWEIGHT.pdf ;
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- ...

Este informe presenta los resultados de la evaluación de diseño vial del proyecto Autopista Vespucio Oriente tramo I, referente a los estándares del diseño geométrico y de seguridad vial del proyecto presentado por la concesionaria OHL al Servicio de Evaluación Ambiental SEIA en noviembre del 2016.

Se evaluaron las áreas del proyecto, cotejandolas con la normativa vigente en el Manual de Carreteras MOP, específicamente con las normativas de: diseño vial de autopistas, diseño geométrico de túneles, diseño geométrico de viaductos y diseño geométrico de ciclovías.

Además, se evaluó el cumplimiento normativo del proyecto con: la Ley General de Urbanismo y construcción, la Ordenanza General de Urbanismo y Construcciones (OGUC), la Ley de Concesiones, las Bases de Licitación, la Ley de Tránsito 18.390, el Plan Regulador Metropolitano de Santiago (PRMS), los planes reguladores (PRC) de las comunas en el área de intervención, el Manual de Recomendaciones de Diseño Vial Urbano (REDEVU) y el Manual de diseño de vialidad cicloinclusiva.

Los resultados y conclusiones de este informe fueron presentados por el autor al Servicio de Evaluación Ambiental (SEIA), en el marco del proceso de participación ciudadana del Estudio de Impacto Ambiental (EIA) del proyecto Autopista Vespucio Oriente (AVO).

— Field surveys or raw elevation data for designing roads and the equipment required are not readily available to potential users of a digital elevation model. The availability of accurate elevation data has thus been a challenge for highway engineers in the preliminary phases of road design. The paper deals with utilization of elevation data of the University of Ilorin, Nigeria for the designing of road constructions. It compares the current elevation data of the University of Ilorin obtained via in situ geodetic measurements with the USGS data set collected via Zonums and Google Earth elevation data. The results obtained establish that there are minor discrepancies between the data from the different sources and the in situ geodetic measurements when used in the geometric design of roads.

A reliable road network is a pre-requisite for economic development. However, the provision of all-weather transportation infrastructure (roads) in developing areas, using traditional design approaches, currently comes at a considerable cost. The construction of a low-volume two lane road in rural and urban areas in Africa may vary from about US$ 500 000/km (2018) in more developed areas, to US$ 1.2 million/km rural areas, or even considerably more in remote areas as influence by material, logistics and safety risks. A general lack of available funds and lack of resources allocated for road infrastructure development is a reality. The current surfaced road network backlog, the lack of resources and the high unit costs make it basically impossible for the Developing World to provide the road infrastructure required to become economically competitive. The high unit costs can be addressed through a change in current engineering practices and the implementation of available and proven new technologies. “New-age” nanotechnology solutions are available to improve the characteristics of naturally available materials to meet the structural engineering requirements for all road pavement layers. These technologies have been proven through laboratory, full scale Accelerated Pavement Tests (APT) tests and practical implementation. The hydrophobic (water-repellent) action achieved through the stabilisation of pavement layers using anionic NME stabilisation agents, to a large extend prevents (or at least considerably inhibits) water from entering pavement layers and causing distress due to a change in the shear strength of the materials in the pavement structure. Traditionally, considerable resources have been allocated towards the prevention of water-damage to roads. Water resistant pavement layers constructed using anionic NME stabilising agents, considerably assists to prevent water from entering and damaging pavement layers. This book provides a comprehensive approach towards the upgrading of gravel / soil roads using naturally available materials stabilised and improved with anionic New-age Modified Emulsions (NME). The aim is to provide all-weather surface roads at an affordable costs, incorporating the best available technologies. This can be achieved without compromising the integrity of the road pavement structure and / or the safety of road users. Applicable standards, together with the implementation of the latest proven developments in material sciences, makes the vision of improved service delivery in terms of a surfaced road networks a reality. The design aims at cost-optimisation from the Inception Phase trough the Design Phase to Construction. The design is based on a simplified design using Dynamic Cone Penetrometer (DCP) tests. Adjustments for the different Climatic Zones of the World are incorporated into the recommended approach. The recommended design approach is easy to implement, requiring no specifically developed design-software for the structural design of the pavement structures. Specifications for the use of anionic NME stabilising agents are recommended to ensure that the material can be implemented with ease in remote areas, requiring a guaranteed shelf-life in excess of four (4) months from suppliers. The anionic NME recommended for use are ideally suited for the construction of roads in all environments, with a high guaranteed stability, requiring no pre-heating during construction, normally experienced in the Developing World. Depending on the needs and policy, the materials recommended are suitable for implementation using and adapting construction methods and equipment. Implementation could vary from the optimisation of opportunities for labour-intensive construction and the development of small and medium enterprises to the use of conventical equipment (water carts, graders and rollers) to the use of modern recyclers and central mixing plants, in combination with paving equipment to construct pavement layers to high levels of accuracy. The book is divided into the following Chapters and Appendices: - Chapter 1: Introduction; - Chapter 2: Non-Technical Influences; - Chapter 3: Phase 1A: Concept Development – Initial Assessment; - Chapter 4: Phase 1B: Concept Development – Detailed Assessment; - Chapter 5: Phase 2: Design; - Chapter 6: Life-cycle Cost Comparison of Applicable Options; - Appendix A: Earth science: Petrology / Geology / Lithology; - Appendix B: Soil Classification; - Appendix C: Recommended DCP Analysis and Design Method Applicable to the Structural assessment of the Bearing Capacity for the Upgrading of Gravel / Soil Roads; - Appendix D: Köppen Climate Classification System with Köppen-Geiger Maps, and - Appendix E: Recommended Project Specifications Adjusted with Specific Reference to the use of Anionic New-age Modified Emulsions (NME) for the Stabilisation of Naturally Available Materials.

Cele mai frecvente structuri rutiere din țara noatră sunt cele suple și semirigide. Acestea prezintă straturi și grosimi de straturi variate în principal în baza diferențelor dintre standardele de dimensionare valabile în diferite perioade de timp. Modificările standardelor au vizat de-a lungul timpului aportul traficului de calcul în dimensionarea structurilor rutiere. Astfel, se impune o analiză mai atentă a factorilor ce influențează valoarea traficului de calcul. În acest articol este prezentată o paralelă între valorile coeficienților propuși de către cele mai recente ediții ale AND 584 din 2002 și 2012. Suplimentar, pentru evidențierea implicațiilor reale ale coeficienților traficului de calcul în calculul dimensionării a fost inclusă și o analiză a datelor empirice colectate cu ajutorul dispozitivului WIM.

The use of LWD in flexible pavement structural designs is increasing. The LWDs are offered under 2 typologies; with or without geophones to set the deflection bowl. LWDs with geophones allow to apply mechanistic analysis directly, but LWDs without geophones not.
For this reason, the LEMaC Center for Road Research UTN FRLP - CIC PBA (Argentina) analyzes this problem through a research project; their results allow the use of LWD without geophones in pavement design using the AASHTO93 Guide.
This “short report”, as allowed by the Letters Academy, presents a summary of the tasks performed and the work procedure developed. No section of conclusions and exhaustive antecedents and studies of the models presented are included, due to the limit imposed on the number of words for these “short reports”. This information can be consulted in the “Correlation model for the use of modulus back-calculation on LWD measurements” (Rivera & Alderete, 2012).

Road reconstruction projects are in the forefront of investments in Poland. The city of Lublin spends considerable sums on road reconstruction and draws financial support from the EU funds. However, it has to be highlighted that such projects are the main threat to street greenery, in particular, to trees, as they frequently result in significant tree felling. The paper presents this problem on the example of modernisation of Racławickie Avenue (Aleje Racławickie) and neighbouring streets in Lublin. The article explains the project’s transport paradigm and the hierarchy of values on which it is based, including the place of greenery. Moreover, the paper identifies the laws governing the roadway system and elaborates on negative results of the project. The paper suggests
also, directions of the development of alternative solutions connected with stand maintenance based on sustainability principle.

A well-established transportation system is not only key to national growth but also a catalyst for economic development of a country which provides a high level of accessibility that maximizes urban residents&amp;#39; access to economic and social opportunities (Todd, 2020). Across the world, traffic congestion has been a significant issue to most cities like Bamenda. As cities continue to thrive and as population increases, it is inevitable that managing traffic congestion will become more critical. The socio-demographic and population explosion experienced by the Bamenda city has changed its settlement pattern, coupled with the deplorable nature of the road network. This examines the state of urban roads and the implications on mobility in the city of Bamenda. Through a quantitative and qualitative methodological approach, a descriptive research design via random and purposive sampling techniques is used for primary data collection from observation and conducted interviews over field realities. The targeted population consisted of drivers, motorists, pedestrians, vendors and stakeholders in the transport sector. 210 questionnaires were administered to Bamenda I, II and III. Secondary data was collected from published and unpublished scientific works. Findings reveal that the nature of the urban road network is the major cause of traffic congestion in the city representing 55.3 % among other factors. Out of the 562.1km length of roads in the city, 475.9km are poorly constructed, characterised by potholes that impose speed breaks to moving vehicles. The roads are deplorable, made up of patches of tar, covered with dust and mud in the different seasons of the year. Only 13km of the roads are well constructed and tarred, which hinders sustainable transportation. The proposed planning measures include the improvement of the road system, installation of traffic signals, provision of traffic guidance, enforcement of parking rules and regulations, as well as increase in the use of the bus system, among others. The study further recommends that the Government of Cameroon should provide regional transportation authorities with more powers and resources to plan, coordinate and implement all urban infrastructure projects in the city. This will ensure planning for congestion that will effectively be in line with the land use plan of the city.