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Kerbs play an important role in providing structural support to the road. The compressive strength of concrete is often the only design consideration. Premature kerb failure is common indicating that only considering compressive strength in design may not be sufficient. Flexural/bending strength, deflection capacity, impact resistance, water absorption/sorption, abrasion resistance, and freeze-thaw resistance can also be important. The use of recycled products in concrete has been an active area of research in recent years and concrete produced from recycled concrete aggregate (RCA) and tyre-derived aggregate (TDA) could be a cleaner and more sustainable alternative to conventional concrete. In this study, ten different concrete mixes were developed for a target strength of 25MPa and tested for mechanical and durability properties. Significant variations in the mechanical properties of different concrete were observed despite all concrete having similar compressive strength. The addition of TDA was found to improve flexural strength, deflection, and abrasion resistance properties, however, it led to inferior impact resistance and higher shrinkage compared to control concrete. A carbon footprint analysis showed that the use of 100% RCA (replacing natural aggregates) could drastically reduce the carbon footprint of concrete. For concrete with TDA aggregate, some environmental benefits of recycling TDA may get offset by the additional binder requirement to achieve the desired compressive strength. Refereed/Peer-reviewed

Kerb is an integral part of road infrastructure and performs several important functions, including providing stability to the edges of the road and providing effective drainage. Their performance can significantly influence the behaviour and service life of a road. The design conditions, construction materials and their sustainability can be important to assess from an asset management and sustainable construction point of view even though this area has been paid limited research attention in the past. This paper reviews the available literature on the design and construction considerations for kerbs and critically analyses them with a special focus on sustainable construction practice. The different materials commonly used around the world for the construction of kerb in terms of their properties, failure and available design guidelines have been discussed along with their management practice. Special situations, such as expansive soil movement and tree root-related problems, have also been considered, and the current guidelines for designing in such situations have also been discussed. A carbon footprint and sustainability analysis has been conducted on the current practice of using natural aggregate concrete and compared against several potential alternatives. The review of the design process indicated that the current practice relies on oversimplified design procedures and identified scopes for improvement, especially with the incorporation of mechanical behaviour of the material being used in construction. The carbon footprint and sustainability analysis indicated that the use of alternative materials could result in significant savings in the kerb construction industry’s carbon footprint. Refereed/Peer-reviewed

During manual wheelchair (MWC) locomotion, the user's upper limbs are subject to significant levels of stress and fatigue because the upper body is permanently engaged to propel the MWC and in all daily activities (van der Woude et al., 2001). This stress can lead to pain and wounds in the upper limbs which in turn may lead to difficulties in autonomy and social integration for MWC users. Suggesting adequate and accessible paths for urban locomotion to MWC users could be a way to reduce the loads sustained by the upper limbs for this population. Tools for suggesting accessible places have already been forwarded in several smartphone applications, but no solution is currently able to provide the best accessible path to move from one place to another. This primarily requires the definition of a quantitative criterion that can be linked to the user’ individual physical capacities In the literature, the physical difficulty of a situation is generally described using either the propelling torque (i.e. the torque acting at the wheel hub and that ensure the wheel rotation) or through the total force applied by the user on the handrim (Koontz et al., 2005; Richter et al., 2007). However, it is unknown if the ranking of the situation difficulty based on these two criteria are equivalent. Hence, the aim of this preliminary study was to evaluate the ranking of various environmental situations according to the two previous criteria: propelling torque and the handrim total force. This study was supported by the French National Agency (ANR-19-CE19-0007).

Syftet med det här projektet har varit att identifiera svårigheterna med att sköta drift och underhåll av trafiksäkerhets- och tillgänglighetsåtgärder och att hitta möjliga lösningar på problemen. Fokus har varit på utformning i tätort samt med tyngdpunkt på tillgänglighetsåtgärder för oskyddade trafikanter, framförallt de med funktionshinder. Projektet har omfattat litteraturstudier, intervjuer och medföljandestudier med kommunal drifts- och planeringspersonal, expertseminarier samt en enkätundersökning bland landets alla kommuner. Utifrån dessa studier kan konstateras att det finns all anledning att ur ett drift- och underhållsperspektiv se över detaljutformningen av främst övergångsställen. Svårigheten ligger i att hitta en balans mellan olika mål och intressen som trafiksäkerhet, tillgänglighet och estetik samt praktiskt utförande och kostnader. Studierna i projektet visar entydigt att manuell skötsel bör undvikas, eftersom detaljer som exempelvis måste handskottas i praktiken blir dåligt eller inte alls åtgärdade. Det som är tillgängligt för alla under barmarksförhållanden är därmed inte tillgängligt för alla under vintern. All användning av plattor och marksten ökar behovet av drift och underhåll eftersom det lätt blir ojämnheter och växer ogräs i skarvarna. Taktila plattor är extra problematiska i och med att de är svåra att rengöra. De slits också ned i samband med driften och förlorar därmed sin funktion. Annars är det riktningsvisande kanter för synskadade och den 0,9 till 1 meter breda rampen till nollnivå som ska underlätta för rörelsehindrade att korsa en gata som är de utformningsdetaljer som utgör störst problem för driften. Möjligheten att använda sig av mindre fordon vid snöröjningen har undersökts, men med slutsatsen att det i dagsläget inte är ett alternativ. Däremot skulle en utökning av bredden på nollnivån till 1,5 meter kunna vara en lösning och upphöjningen i mittrefugen skulle kunna ersättas av tre rader med kupolplattor. För att kunna upprätthålla tillgänglighet och trafiksäkerhet vid alla förhållanden, behöver driftfrågorna beaktas i planerings- och projekteringsskedet och driftrutiner och metoder behöver anpassas för de nya utformningsdetaljerna. The aim of this project was to identify the difficulties associated with carrying out the operation and maintenance of road safety and accessibility measures and to find possible solutions. The focus has been on design in urban areas, with the emphasis on accessibility measures for vulnerable road users, especially handicapped. The project has included a literature review, interviews with municipal operational and planning staff, expert seminars, and a questionnaire survey among all municipalities in Sweden. These studies show that there is reason to examine detailed design from an operational and maintenance perspective, especially at pedestrian crossings. The difficulty lies in finding a balance between road safety, accessibility and aesthetics, and to carry out maintenance and operation within the budgetary restrictions. The studies unambiguously show that manual operations should be avoided, since work which must be carried out by hand is poorly or not at all performed. What is accessible to all in the summertime is thus not accessible to all during winter conditions. All uses of slabs and brick pavers increase the need for maintenance since they easily become uneven and weeds grow in the joints. The tactile slabs are also difficult to clean, and are worn down in use and thus gradually lose their function. Other design details which are difficult to service is the directional edge guiding a visually impaired person across the street from a pedestrian crossing, and the 0.9-1.0 m wide ramp down to carriageway level to make it easier for the physically disabled to cross a street. It seems to be especially difficult to service the raised edge in the central refuge, and it is therefore a measure which many municipalities have decided to omit. The possibility to use smaller vehicles in snow clearance has been investigated with the conclusion that at the present this is not an option. There is a lower limit to vehicle size, with regard to both capacity and stability. On the other hand, increase of the ramp width up to 1.5 m could solve the problems and the raised edge in the central refuge could be replaced by three rows of domed slabs. In order to retain accessibility and road safety in all conditions, operational issues must be considered in the planning and design stage, and operational routines and methods need to be adapted to the new design details.

Det övergripande syftet med projektet "Trafiksäkerhet & Tillgänglighet vs Drift & Underhåll" är att finna lösningar på de konflikter som finns mellan de utformningslösningar som vi idag betraktar som tillgängliga och trafiksäkra och de problem som dessa utformningar utgör för drift- och underhållsarbetet. Ur ett helhetsperspektiv kan man idag få bilden av att man kanske fokuserar för mycket på att det ska vara optimalt ur ett trafiksäkerhets- och tillgänglighetsperspektiv, vilket i vissa fall innebär att det blir omöjligt att klara driften. Det i sin tur innebär att utformningen varken blir säker eller tillgänglig under vissa förhållanden. Vårt mål är att hitta lösningar som kan anses som tillräckligt bra ur ett trafiksäkerhets- och tillgänglighetsperspektiv och som dessutom går att sköta och ge godtagbar standard året om.

The aim of the current study was to describe the accident and injury situations associated with cyclists. The study was based on information obtained from STRADA (Swedish Traffic Accident Data Acquisition), including the descriptions and details of the events leading up to the accidents. Travel data from the Swedish national travel survey was also utilised, enabling the risk situation for cyclists to be assessed. The most common accidents among cyclists were single accidents, accounting for 72% of all cyclists injured. Next most common, with 17%, were accidents involving motor vehicles, followed by accidents between cyclists, with 8%. The biggest influencing factor in the cause of single accidents was slippery surfaces, stated as a contributory cause in 23% of the accidents. Snow and ice were the main causes but loose grit, from winter maintenance, was also frequently given as a reason. Kerbstone edging, uneven road surfaces, collisions with temporary or permanent objects were also stated as the cause of many single accidents. Alcohol influence was another common contributory cause. The risk of being injured as a cyclist in traffic was as likely for both male and female genders. The highest risk groups were those of the young and the elderly.

This paper describes the results of research aimed at studying the possible usage of bottom ash (BA) and granulated blast-furnace slag (GBFS) in production of plain concrete elements. Sufficient number of briquettes, paving blocks and kerbs specimens containing GBFS and BA as fine aggregate replacement were produced in laboratory. Then, some of tests were conducted for investigating durability and mechanical properties of these specimens. Unit weight, compression strength and freeze-thaw tests were conducted for briquette specimens. Compression strength, freeze-thaw, water absorption and surface abrasion tests were conducted for paving blocks. Surface abrasion and flexural tensile strength tests were conducted for kerb specimens. While compression strength was decreased slightly, durability characteristics such as resistance of freeze-thaw and abrasion were improved. The results showed that usage of partially fine aggregate of these industrial by-products has more beneficial effects on durability characteristics of plain concrete elements. © 2006 Elsevier Ltd. All rights reserved.