The objective of this study was to compile experiences regarding efforts by road authorities to satisfy the needs for efficient maintenance and the results of such efforts. The extent to which maintenance aspects are considered during road planning and design, as a potential for improvement of maintenance efficiency is studied. The study shows that such efforts have in many cases resulted in reduced maintenance costs. However, there are also indications that maintenance standards in some cases have declined, as the focus has been on reduction of the rate of recurring maintenance activities and prioritisation of some maintenance measures, e.g. winter maintenance, over other maintenance measures, e.g. pavement maintenance. The study also shows that efforts towards increased maintenance efficiency have one thing in common – namely that the main focus has been on improving operating practices and maintenance procedures. Road authorities have mostly ignored the improvement potentials that exist during the planning and design process through consideration of the interrelationship between geometrical road design and maintenance.
The cost of a road construction over its service life is a function of the design, quality of construction, maintenance strategies and maintenance operations. Unfortunately, designers often neglect a very important aspect which is the possibility to perform future maintenance activities. The focus is mainly on other aspects such as investment costs, traffic safety, aesthetic appearance, regional development and environmental effects. This licentiate thesis is a part of a Ph.D. project entitled “Road Design for lower maintenance costs” that aims to examine how the life-cycle costs can be optimized by selection of appropriate geometrical designs for the roads and their components. The result is expected to give a basis for a new method used in the road planning and design process using life-cycle cost analysis with particular emphasis on road maintenance. The project started with a review of literature with the intention to study conditions causing increased needs for road maintenance, the efforts made by the road authorities to satisfy those needs and the improvement potential by consideration of maintenance aspects during planning and design. An investigation was carried out to identify the problems which obstruct due consideration of maintenance aspects during the road planning and design process. This investigation focused mainly on the road planning and design process at the Swedish Road Administration. However, the road planning and design process in Denmark, Finland and Norway were also roughly evaluated to gain a broader knowledge about the research subject. The investigation was carried out in two phases: data collection and data analysis. Data was collected by semi-structured interviews with expert actors involved in planning, design and maintenance and by a review of design-related documents. Data analyses were carried out using a method called “Change Analysis”. This investigation revealed a complex combination of problems which result in inadequate consideration of maintenance aspects. Several urgent needs for changes to eliminate these problems were identified. Another study was carried out to develop a model for calculation of the repair costs for damages of different road barrier types and to analyse how factors such as road type, speed limits, barrier types, barrier placement, type of road section, alignment and seasonal effects affect the barrier damages and the associated repair costs. This study was carried out using a method called the “Case Study Research Method”. Data was collected from 1087 barrier repairs in two regional offices of the Swedish Road Administration, the Central Region and the Western Region. A table was established for both regions containing the repair cost per vehicle kilometre for different combinations of barrier types, road types and speed limits. This table can be used by the designers in the calculation of the life-cycle costs for different road barrier types.
The cost of a road construction over its service life is a function of design, quality of construction as well as maintenance strategies and operations. An optimal life-cycle cost for a road requires evaluations of the above mentioned components. Unfortunately, road designers often neglect a very important aspect, namely, the possibility to perform future maintenance activities. Focus is mainly directed towards other aspects such as investment costs, traffic safety, aesthetic appearance, regional development and environmental effects. This doctoral thesis presents the results of a research project aimed to increase consideration of road maintenance aspects in the planning and design process. The following subgoals were established: Identify the obstacles that prevent adequate consideration of future maintenance during the road planning and design process; and Examine optimisation of life-cycle costs as an approach towards increased efficiency during the road planning and design process. The research project started with a literature review aimed at evaluating the extent to which maintenance aspects are considered during road planning and design as an improvement potential for maintenance efficiency. Efforts made by road authorities to increase efficiency, especially maintenance efficiency, were evaluated. The results indicated that all the evaluated efforts had one thing in common, namely ignorance of the interrelationship between geometrical road design and maintenance as an effective tool to increase maintenance efficiency. Focus has mainly been on improving operating practises and maintenance procedures. This fact might also explain why some efforts to increase maintenance efficiency have been less successful. An investigation was conducted to identify the problems and difficulties, which obstruct due consideration of maintainability during the road planning and design process. A method called “Change Analysis” was used to analyse data collected during interviews with experts in road design and maintenance. The study indicated a complex combination of problems which result in inadequate consideration of maintenance aspects when planning and designing roads. The identified problems were classified into six categories: insufficient consulting, insufficient knowledge, regulations and specifications without consideration of maintenance aspects, insufficient planning and design activities, inadequate organisation and demands from other authorities. Several urgent needs for changes to eliminate these problems were identified. One of the problems identified in the above mentioned study as an obstacle for due consideration of maintenance aspects during road design was the absence of a model for calculating life-cycle costs for roads. Because of this lack of knowledge, the research project focused on implementing a new approach for calculating and analysing life-cycle costs for roads with emphasis on the relationship between road design and road maintainability. Road barriers were chosen as an example. The ambition is to develop this approach to cover other road components at a later stage. A study was conducted to quantify repair rates for barriers and associated repair costs as one of the major maintenance costs for road barriers. A method called “Case Study Research Method” was used to analyse the effect of several factors on barrier repairs costs, such as barrier type, road type, posted speed and seasonal effect. The analyses were based on documented data associated with 1625 repairs conducted in four different geographical regions in Sweden during 2006. A model for calculation of average repair costs per vehicle kilometres was created. Significant differences in the barrier repair costs were found between the studied barrier types. In another study, the injuries associated with road barrier collisions and the corresponding influencing factors were analysed. The analyses in this study were based on documented data from actual barrier collisions between 2005 and 2008 in Sweden. The result was used to calculate the cost for injuries associated with barrier collisions as a part of the socio-economic cost for road barriers. The results showed significant differences in the number of injuries associated with collisions with different barrier types. To calculate and analyse life-cycle costs for road barriers a new approach was developed based on a method called “Activity-based Life-cycle Costing”. By modelling uncertainties, the presented approach gives a possibility to identify and analyse factors crucial for optimising life-cycle costs. The study showed a great potential to increase road maintenance efficiency through road design. It also showed that road components with low investment costs might not be the best choice when including maintenance and socio-economic aspects. The difficulties and problems faced during the collection of data for calculating life-cycle costs for road barriers indicated a great need for improving current data collecting and archiving procedures. The research focused on Swedish road planning and design. However, the conclusions can be applied to other Nordic countries, where weather conditions and road design practices are similar. The general methodological approaches used in this research project may be applied also to other studies.
This paper presents an investigation conducted to identify obstacles that prevent sufficient consideration of future road maintenance needs during the road planning and design phase. The investigation focuses on the road planning and design process within the Swedish Road Administration. For this reason the results are applicable for Nordic conditions concerning road design, maintenance, and climate. However, the results focus on general aspects of the planning and design process and ought to also be valid for other conditions outside the Nordic countries. The investigation was carried out using a method called ᅵchange analysis,ᅵ which consists of complementary steps for the analysis of problems, processes, and goals in order to identify necessary changes. The investigation identified several problems within the road planning and design process related to consulting, knowledge, planning and design activities, regulations, organization structure, and demands from other authorities. The
Denna arbetsrapport presenterar en studie som utfördes i syfte att undersöka hur vägbarriärer påverkar utförandet av plogningen och till detta relaterade kostnader. Målet var att kunna identifiera och beräkna de eventuella ökningar i snöplogningskostnaderna som tillkommer på grund av vägbarriärer. Studien utfördes med hjälp av en metod som heter ”Case Study Reasearch Strategy”. Fältstudier av snöplogningen utfördes på 6 vägsträckor. Fältstudierna täckte fyra vägtyper: motorväg, mötesfria vägar, 4-fältiga vägar och målade 2+1-vägar. De barriärtyper som studerades var betongbarriär, stållineräcke, rörräcke och w-profilräcke. Plogningskvalité, arbetsmiljö, trafiksäkerhet och framkomlighet studerades med hjälp av direkta observationer av plogningsaktiviteter på fält. Genom at mäta tiden för att ploga en viss sträcka bestämdes plogningshastigheten. Resultatet visade att vägbarriärtypen påverkar varken snöplogningshastigheten eller plogningstiden nämnvärt. Vidare visade resultatet att vägbarriärtypen inte påverkar snöplogningskvaliteten längs med mittremsan. Däremot, försämras plogningskvalitén längs vägrenar med betongbarriärar eller w-profilräcken som sidobarriärer. Det är dock svårt att beräkna de kostnader som tillkommer på grund av försämrad plogningskvalité. Trots att både trafiksäkerheten och framkomligheten försämrades drastiskt under plogningen, kunde man konstatera att dessa två aspekter inte påverkades av vägbarriärtypen.
För att kunna bygga en ny väg måste den först planeras och projekteras. Vägplanering innebär att man undersöker förutsättningarna för att bygga vägen t.ex. konsekvenser för miljö, samhälle, trafiksäkerhet, framkomlighet, tillgänglighet samt tekniska och ekonomiska förutsättningar. Vägprojektering innebär att man bestämmer vägens utformning på detaljnivå t.ex. vägsträckning, bredd, profil, vägutrustning, etc. Planering och projektering av vägar är en komplicerad process med tanke på alla komponenter som en väg består av samt alla aspekter som man måste ta hänsyn till under vägens livstid. Planerings- och projekteringsprocessen utgör en avvägning av många aspekter för att hitta den optimala lösningen. Drift- och underhållsåtgärder på vägnätet föranleds ofta av att problem uppstått på ett fåtal ställen. Kostnaden för att åtgärda dessa ställen kan uppgå till stora belopp under vägens livslängd. Med en lämpligare utformning av vägen hade dessa problem i en del fall sannolikt kunnat undvikas. Bland de aktörer, som är inblandade i planerings- och projekteringsprocessen, finns det olika åsikter om orsaken till att man inte tar tillräcklig hänsyn till drift- och underhållaspekten under planerings- och projekteringsskedet. Vissa aktörer tycker att det är projektörens kunskapsbrister som leder till att vägen får olämplig utformning avseende drift och underhåll. Andra tycker att det är en kombination av olika brister hos väghållaren. Dessa brister kan då finnas i såväl planerings- och projekteringsprocessen som i drift- och underhållsprocessen. Denna rapport presenterar resultatet för en förstudie som har utförts inom doktorandprojektet ”Vägprojektering för minskade drift- och underhållskostnader”. Syftet med förstudien var att identifiera brister och problem på övergripande nivå som leder till att man inte tar tillräcklig hänsyn till drift- och underhållsaspekten vid planerings- och projekteringsprocessen. Ett annat syfte med förstudien var att föreslå förändringsbehov inom planerings- och projekteringsprocessen genom att analysera de identifierade problemen, analysera verksamheten vid planering och projektering, analysera verksamhetens mål, formulera nya mål för verksamheten och fastställa de nödvändiga förändringsbehoven.
This study aimed at applying and evaluating a new approach for analyzing life-cycle costs for road components during the road planning and design process. Road median barriers were chosen as an example. The approach is based on a method called “Activity-Based Life-Cycle Costing using the Monte Carlo Simulation” for managing future costs and the associated risks. The results show a potential for increasing efficiency throughout the road planning and design process by minimizing the life-cycle costs of road components. The results also show that implementation of life-cycle cost analyses in the road planning and design process is possible, but difficult, mainly due to lack of relevant data.
This paper presents a study aimed at quantifying and comparing the risk of personal injuries associated with road barrier collisions. Documented data from actual barrier collisions, including post-impact collisions, in Sweden between 2005 and 2008 were analyzed. The analyses were based on the injury classification made by healthcare services. The injury rates, measured in number of injuries per vehicle kilometer travelled, were calculated for the different injury classes as a basis for evaluating barrier performance. The results show that the rate of injuries was higher due to collisions with flexible barrier systems, such as cable barrier, than with other semi-rigid and rigid barrier system, such as w-beam and concrete barriers. This result might be explained by a high rate of post-impact events, such as post-impact collisions, roll-overs and over-rides, associated with the placement and mechanical properties of the cable barriers. The study also showed a considerable difference in injury classifications made by the police and the healthcare services, as well as a considerable under-reporting of barrier collisions by the police.