The northernmost highway district of Lapland, Finland, differs considerably from other regions in... more The northernmost highway district of Lapland, Finland, differs considerably from other regions in Finland. Its road network is very long, about 9000 km, whereas traffic volumes are low because of an extremely low population density. The arctic climate puts severe restrictions on the technology used, the amount and quality of winter maintenance, and road standards. To fully comprehend the implications of proposed budget cuts, the district initiated an analysis on the impacts of alternative strategies. A network-level pavement management system was used to allocate and optimize funds for rehabilitation and to analyze the development of the condition of the network with nonoptimal funds. Summer and winter maintenance were analyzed by an analytical hierarchical process. As to investments, in addition to a traditional cost-benefit analysis, indirect economic effects were studied with a regionalized input-output model. According to the results the pavement condition targets cannot be achi...
Page 1. PAVEMENT MANAGEMENT AS CONCEPT FOR THE MANAGEMENT OF TRANSPORTATION SERVICES Juha S. Äijö... more Page 1. PAVEMENT MANAGEMENT AS CONCEPT FOR THE MANAGEMENT OF TRANSPORTATION SERVICES Juha S. Äijö and Kimmo A. Tikka 100 Gen Ltd. Tekniikantie 12 FIN - 02150 Espoo, Finland Abstract The Ministry ...
In the beginning of the 1990's FinnRA suggested decreasing resources for the Lapland highway ... more In the beginning of the 1990's FinnRA suggested decreasing resources for the Lapland highway district whereas the district felt that such a policy would have very harmful long term effects. To fully comprehend the implications of the proposed budget cuts, the district initiated a study on the impacts of different strategy alternatives on the road network condition, agency and user costs, maintenance level of service and on the regional economy. In this study, a network level pavement management system was used to allocate and optimize funds for rehabilitation. Summer and winter maintenance was analyzed with analytical hierarchical process and as to investments in addition to traditional cost benefit analysis, regional multiplier effects were studied with a regionalized input output model. It is evident that rehabilitation, summer and winter maintenance, and highway investments cannot be viewed independently of each other. Road keeping has to be seen as a whole and the optimization of its sub-components has to be done simultaneously. Mathematically speaking this means that pavement maintenance, summer and winter maintenance, and highway investments are non-separable from each other and that the optimization function has to cover them all.
Glider observations conducted between 2016 and 2021 were combined with shipborne surveys from the... more Glider observations conducted between 2016 and 2021 were combined with shipborne surveys from the 1950s through the 2010s to provide critically important information about changes in the Bothnian Sea. Particularly, we evaluated the rate of warming and freshening in several layers of the basin and showed that warming of 0.3°C/decade in the upper 25m was sufficient to explain ~40% of the oxygen depletion since the mid-1950s. This depletion was driven by limited saturation of the surface mixed layer (SML), caused by warming and a (related) weakening of the surface oxygen flux during spring blooms. Below the SML, the role of warming in oxygen depletion decreased to less than 30%, whereas the role of freshening became increasingly important via establishing stronger stratification that reduced local ventilation across the basin’s halocline. The observed values in this study are not critical for the ecological system of the Bothnian Sea. However, the presented trends towards oxygen deplet...
The Finnish National Road Administration (FinnRA) has been developing pavement management systems... more The Finnish National Road Administration (FinnRA) has been developing pavement management systems (PMSs) since the late 1970s. By now, the following systems of the pavement management process have been implemented and are in use: the network-level system, Highway Investment Programming System (HIPS); the project-level system, PMS91; and the road condition data register (KURRE + RDB). HIPS is used for strategic decision making by the central administration (FinnRA). Recommendations for budget levels and maintenance measures from the model have been transferred to nine highway districts to their project-level PMSs for capital programming. The condition register contains all relevant information on road condition needed in both PMSs. Basic information on, for example, traffic and construction history is retrieved from the road data bank. As in many other road agencies around the world, the development and implementation of these systems has appeared to be time-consuming, laborious, and...
ABSTRACT The coastal areas of Finland are covered with islands and shoals of variable sizes. The ... more ABSTRACT The coastal areas of Finland are covered with islands and shoals of variable sizes. The total amount of islands is over 73 000. Ca. 40 000 of the islands are located in the south-western extremity of Finland in the Archipelago Sea. The size of the islands varies from a few meters to several kilometres in diameter. The bathymetry is complex; there are many shoals which cause depth-induced wave refraction and wave breaking. Some of these areas have potential to generate high concentration of wave energy and even caustics. The accurate modelling of the wave field in the archipelago areas is essential for the safety of the marine traffic, the marine spatial planning and the modelling of the coupled physical-biogeochemical processes in the coastal waters. The wave field in the Archipelago Sea was modelled with the wave model WAM using ten different realisations of high-resolution grids. Two different resolutions were used, 0.5 nmi and 0.1 nmi, with different ways to define the land mask and grid obstructions in the archipelago areas. The modelled wave field inside the Archipelago Sea was compared against measurements made during a research cruise of R/V Aranda in September 2010. The depth-induced wave breaking and wave refraction were shown to have significant effect on the modelled wave field at the southern edge of the Archipelago Sea when the 0.1 nmi resolution grids were used. Inside the Archipelago Sea the 0.1 nmi grids predicted the local wind waves with good accuracy when the forcing wind field was in agreement with the measurements. However, due to the coarse temporal and spatial resolution of the forcing wind field, WAM was unable to represent the temporal variability of the wave parameters in full detail. The attenuation of the open sea waves propagating into the Archipelago Sea was slightly overestimated by the 0.1 nmi grids. The computational demands of the 0.1 nmi resolution grids restrict their use e.g. in operational forecasting. Therefore, coarser resolution grids that are able to model the wave field with sufficient accuracy are needed. The 0.5 nmi resolution grids were unable to describe the depth-induced wave breaking and refraction in as much detail as the 0.1 nmi grids. Furthermore, the 0.5 nmi grids overestimated the energy of the local wind waves and underestimated the attenuation of the open sea waves. However, when grid obstructions were used in the 0.5 nmi grids, the attenuation of wave energy was predicted with good accuracy, but the energy of the local wind waves was slightly overestimated. Development of additional methods that take into account the wave refraction and wave breaking in sub-grid scale might further improve the accuracy of the coarser resolution grids in modelling of the wave field in archipelago areas.
A study is reported in which a network level pavement management system was used in Finland to al... more A study is reported in which a network level pavement management system was used in Finland to allocate and optimize funds for rehabilitation. Summer and winter maintenance was analyzed with analytical hierarchical process in relation to investsments and cost benefit analyses. Regional multiplier effects were studied with a regionalized input output model. It is noted that rehabilitation, summer and winter maintenance, and highway investments cannot be viewed independently of each other, and the optimization function must cover them all.
The coastal areas of Finland are covered with islands and shoals of variable sizes. The total amo... more The coastal areas of Finland are covered with islands and shoals of variable sizes. The total amount of islands is over 73 000. Ca. 40 000 of the islands are located in the south-western extremity of Finland in the Archipelago Sea. The size of the islands varies from a few meters to several kilometres in diameter. The bathymetry is complex; there are many shoals which cause depth-induced wave refraction and wave breaking. Some of these areas have potential to generate high concentration of wave energy and even caustics. The accurate modelling of the wave field in the archipelago areas is essential for the safety of the marine traffic, the marine spatial planning and the modelling of the coupled physical-biogeochemical processes in the coastal waters. The wave field in the Archipelago Sea was modelled with the wave model WAM using ten different realisations of high-resolution grids. Two different resolutions were used, 0.5 nmi and 0.1 nmi, with different ways to define the land mask ...
2014 IEEE/OES Baltic International Symposium (BALTIC), 2014
ABSTRACT The coastal area off Helsinki in the Gulf of Finland has both a complex shoreline and ba... more ABSTRACT The coastal area off Helsinki in the Gulf of Finland has both a complex shoreline and bathymetry which makes modelling the wave field especially challenging. Experience has shown, that these types of areas generally benefits from the use of a high-resolution model grid. Even though the coastal area is very sensitive to the resolution, this is not necessarily true for the boundary field used to force the nested grid. The area outside Helsinki was modelled with the third generation spectral wave model WAM, using a high-resolution 0.1 nmi grid. This nested grid was forced with boundary fields with two different resolutions (1 nmi and 4 nmi), and the difference in significant wave height inside the nested grid due to the change of boundary field is discussed. In comparison to the coarser 4 nmi boundary grid, the finer 1 nmi version was able to model the wave field with higher accuracy near the coastline. This led to an improved accuracy of the modelled significant wave height inside the nested grid also. However, the differences inside the coastal archipelago and at the two wave buoy sites inside the nested grid were insignificant.
The northernmost highway district of Lapland, Finland, differs considerably from other regions in... more The northernmost highway district of Lapland, Finland, differs considerably from other regions in Finland. Its road network is very long, about 9000 km, whereas traffic volumes are low because of an extremely low population density. The arctic climate puts severe restrictions on the technology used, the amount and quality of winter maintenance, and road standards. To fully comprehend the implications of proposed budget cuts, the district initiated an analysis on the impacts of alternative strategies. A network-level pavement management system was used to allocate and optimize funds for rehabilitation and to analyze the development of the condition of the network with nonoptimal funds. Summer and winter maintenance were analyzed by an analytical hierarchical process. As to investments, in addition to a traditional cost-benefit analysis, indirect economic effects were studied with a regionalized input-output model. According to the results the pavement condition targets cannot be achi...
Page 1. PAVEMENT MANAGEMENT AS CONCEPT FOR THE MANAGEMENT OF TRANSPORTATION SERVICES Juha S. Äijö... more Page 1. PAVEMENT MANAGEMENT AS CONCEPT FOR THE MANAGEMENT OF TRANSPORTATION SERVICES Juha S. Äijö and Kimmo A. Tikka 100 Gen Ltd. Tekniikantie 12 FIN - 02150 Espoo, Finland Abstract The Ministry ...
In the beginning of the 1990's FinnRA suggested decreasing resources for the Lapland highway ... more In the beginning of the 1990's FinnRA suggested decreasing resources for the Lapland highway district whereas the district felt that such a policy would have very harmful long term effects. To fully comprehend the implications of the proposed budget cuts, the district initiated a study on the impacts of different strategy alternatives on the road network condition, agency and user costs, maintenance level of service and on the regional economy. In this study, a network level pavement management system was used to allocate and optimize funds for rehabilitation. Summer and winter maintenance was analyzed with analytical hierarchical process and as to investments in addition to traditional cost benefit analysis, regional multiplier effects were studied with a regionalized input output model. It is evident that rehabilitation, summer and winter maintenance, and highway investments cannot be viewed independently of each other. Road keeping has to be seen as a whole and the optimization of its sub-components has to be done simultaneously. Mathematically speaking this means that pavement maintenance, summer and winter maintenance, and highway investments are non-separable from each other and that the optimization function has to cover them all.
Glider observations conducted between 2016 and 2021 were combined with shipborne surveys from the... more Glider observations conducted between 2016 and 2021 were combined with shipborne surveys from the 1950s through the 2010s to provide critically important information about changes in the Bothnian Sea. Particularly, we evaluated the rate of warming and freshening in several layers of the basin and showed that warming of 0.3°C/decade in the upper 25m was sufficient to explain ~40% of the oxygen depletion since the mid-1950s. This depletion was driven by limited saturation of the surface mixed layer (SML), caused by warming and a (related) weakening of the surface oxygen flux during spring blooms. Below the SML, the role of warming in oxygen depletion decreased to less than 30%, whereas the role of freshening became increasingly important via establishing stronger stratification that reduced local ventilation across the basin’s halocline. The observed values in this study are not critical for the ecological system of the Bothnian Sea. However, the presented trends towards oxygen deplet...
The Finnish National Road Administration (FinnRA) has been developing pavement management systems... more The Finnish National Road Administration (FinnRA) has been developing pavement management systems (PMSs) since the late 1970s. By now, the following systems of the pavement management process have been implemented and are in use: the network-level system, Highway Investment Programming System (HIPS); the project-level system, PMS91; and the road condition data register (KURRE + RDB). HIPS is used for strategic decision making by the central administration (FinnRA). Recommendations for budget levels and maintenance measures from the model have been transferred to nine highway districts to their project-level PMSs for capital programming. The condition register contains all relevant information on road condition needed in both PMSs. Basic information on, for example, traffic and construction history is retrieved from the road data bank. As in many other road agencies around the world, the development and implementation of these systems has appeared to be time-consuming, laborious, and...
ABSTRACT The coastal areas of Finland are covered with islands and shoals of variable sizes. The ... more ABSTRACT The coastal areas of Finland are covered with islands and shoals of variable sizes. The total amount of islands is over 73 000. Ca. 40 000 of the islands are located in the south-western extremity of Finland in the Archipelago Sea. The size of the islands varies from a few meters to several kilometres in diameter. The bathymetry is complex; there are many shoals which cause depth-induced wave refraction and wave breaking. Some of these areas have potential to generate high concentration of wave energy and even caustics. The accurate modelling of the wave field in the archipelago areas is essential for the safety of the marine traffic, the marine spatial planning and the modelling of the coupled physical-biogeochemical processes in the coastal waters. The wave field in the Archipelago Sea was modelled with the wave model WAM using ten different realisations of high-resolution grids. Two different resolutions were used, 0.5 nmi and 0.1 nmi, with different ways to define the land mask and grid obstructions in the archipelago areas. The modelled wave field inside the Archipelago Sea was compared against measurements made during a research cruise of R/V Aranda in September 2010. The depth-induced wave breaking and wave refraction were shown to have significant effect on the modelled wave field at the southern edge of the Archipelago Sea when the 0.1 nmi resolution grids were used. Inside the Archipelago Sea the 0.1 nmi grids predicted the local wind waves with good accuracy when the forcing wind field was in agreement with the measurements. However, due to the coarse temporal and spatial resolution of the forcing wind field, WAM was unable to represent the temporal variability of the wave parameters in full detail. The attenuation of the open sea waves propagating into the Archipelago Sea was slightly overestimated by the 0.1 nmi grids. The computational demands of the 0.1 nmi resolution grids restrict their use e.g. in operational forecasting. Therefore, coarser resolution grids that are able to model the wave field with sufficient accuracy are needed. The 0.5 nmi resolution grids were unable to describe the depth-induced wave breaking and refraction in as much detail as the 0.1 nmi grids. Furthermore, the 0.5 nmi grids overestimated the energy of the local wind waves and underestimated the attenuation of the open sea waves. However, when grid obstructions were used in the 0.5 nmi grids, the attenuation of wave energy was predicted with good accuracy, but the energy of the local wind waves was slightly overestimated. Development of additional methods that take into account the wave refraction and wave breaking in sub-grid scale might further improve the accuracy of the coarser resolution grids in modelling of the wave field in archipelago areas.
A study is reported in which a network level pavement management system was used in Finland to al... more A study is reported in which a network level pavement management system was used in Finland to allocate and optimize funds for rehabilitation. Summer and winter maintenance was analyzed with analytical hierarchical process in relation to investsments and cost benefit analyses. Regional multiplier effects were studied with a regionalized input output model. It is noted that rehabilitation, summer and winter maintenance, and highway investments cannot be viewed independently of each other, and the optimization function must cover them all.
The coastal areas of Finland are covered with islands and shoals of variable sizes. The total amo... more The coastal areas of Finland are covered with islands and shoals of variable sizes. The total amount of islands is over 73 000. Ca. 40 000 of the islands are located in the south-western extremity of Finland in the Archipelago Sea. The size of the islands varies from a few meters to several kilometres in diameter. The bathymetry is complex; there are many shoals which cause depth-induced wave refraction and wave breaking. Some of these areas have potential to generate high concentration of wave energy and even caustics. The accurate modelling of the wave field in the archipelago areas is essential for the safety of the marine traffic, the marine spatial planning and the modelling of the coupled physical-biogeochemical processes in the coastal waters. The wave field in the Archipelago Sea was modelled with the wave model WAM using ten different realisations of high-resolution grids. Two different resolutions were used, 0.5 nmi and 0.1 nmi, with different ways to define the land mask ...
2014 IEEE/OES Baltic International Symposium (BALTIC), 2014
ABSTRACT The coastal area off Helsinki in the Gulf of Finland has both a complex shoreline and ba... more ABSTRACT The coastal area off Helsinki in the Gulf of Finland has both a complex shoreline and bathymetry which makes modelling the wave field especially challenging. Experience has shown, that these types of areas generally benefits from the use of a high-resolution model grid. Even though the coastal area is very sensitive to the resolution, this is not necessarily true for the boundary field used to force the nested grid. The area outside Helsinki was modelled with the third generation spectral wave model WAM, using a high-resolution 0.1 nmi grid. This nested grid was forced with boundary fields with two different resolutions (1 nmi and 4 nmi), and the difference in significant wave height inside the nested grid due to the change of boundary field is discussed. In comparison to the coarser 4 nmi boundary grid, the finer 1 nmi version was able to model the wave field with higher accuracy near the coastline. This led to an improved accuracy of the modelled significant wave height inside the nested grid also. However, the differences inside the coastal archipelago and at the two wave buoy sites inside the nested grid were insignificant.
Uploads
Papers by Kimmo Tikka