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Określenie charakterystyki obciążenia drogi wiąże się z analizą ilościową i jakościową poruszających się po niej pojazdów. Celem pracy było określenie rzeczywistych obciążeń powstałych na osiach zestawu przy transporcie drewna. W pracy przedstawiono wyniki analizy parametrów zestawów do wywozu drewna: masy całkowitej zestawu (GVW), obciążenia poszczególnych osi, jednostkowych ładunków mas drewna. Badania przeprowadzono na 230 samochodach transportujących drewno wielkowymiarowe WC0 i średniowymiarowe S2 w zestawach wywozowych pięcioosiowych i sześcioosiowych. Samochody jednorazowo przewoziły ładunki drewna o wielkości od 20,1 do 43,4 m . Samochody transportujące drewno sosnowe miały masę całkowitą zestawu GVW na poziomie 42,3-60,2 Mg (WC0) oraz 39,7-58,5 Mg (S2). Średnie naciski na poszczególnych osiach zestawu pięcioosiowego z S2 wynosiły 72-106 kN oraz 83-119 kN dla WC0, a w zestawach sześcioosiowych 73-93 kN dla samochodów z S2 i 83-106 kN dla samochodów z WC0.
The economic development of the country is very much dependent on the development of the transport infrastructure, which is one of the main priorities of the state policy included in the planning and development documents. Ensuring a efficiently functioning transport system, primarily the network of roads, involves the need to improve the technical characteristics of existing roads or to build new sections. With the linear nature of road investments, we deal with interference in significant areas that have direct and indirect effects. The aim of the study was to analyze the impact of investments realized for different categories of public roads on the area of land needed to be excluded from forest production. The structure and area of the land as well as the number of forest superintendents transferred areas were also analyzed. The study was conducted for forest areas managed by the State Forests National Forest Holding (SF NFH). Data on the area of the transferred forest land was obtained from SF NFH units and the General Directorate of National Roads and Motorways (GDDKiA). In the years 2012−2015, SF NFH units transferred the land into the management of GDDKiA 203 times with the total area of 617 ha. In the same period, the transfer of the land ownership to local government for voivodship, county and municipal roads took place in 388 cases and covered 556.6 ha. Since 2003 (i.e when special act on road investments came into force), the area of the transferred land amounted to 282.7 ha in Toruń, 78.6 ha in Gdańsk and 558.4 ha in Poznań regional directorates of the State Forests. There was a decrease in the area of the transferred lands depending on the category of public roads, while the highest number of events for municipal roads was observed. There is a great variability in the time, number and area of property transferred to public roads.
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2007
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tom 151
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nr 07
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On the basis of the obtained results it may be assumed that in the total rides of the forest district vehicles greater importance (although limited to a certain degree) will have the rides connected with the administration work, supervision of works and protection of possessions. The changes introduced after 1995 within the scope of works done with the forest districts own vehicles especially in the Golub-Dobrzyń forest district did not affect the rides of passenger vehicles and vans. Analysing the rides in all groups of vehicles it can be stated that they are similar in 30% in the years 1994-1995 and 1998-1999 in the Brodnica forest district and in 70% in the Golub-Dobrzyń firest district. It points to the effect of organizational changes in particular units on the changes in the structure of vehicle rides but this dependence in the Golub-Dobrzyń forest district is observed to a lesser degree.
The purpose of the study was to determine the importance of various parameters of forest roads used by heavy goods vehicles for transporting timber based on the research conducted among drivers and employees working on the road infrastructure of a forest district (road managers). The study analyzed the road parameters presented in the site plan, its vertical structure and type of surface (material). A questionnaire was sent by post to all (430) forest districts in Poland, which resulted in the receipt of 296 correctly completed surveys. Additionally, individual questionnaire interviews (82) were conducted with drivers of heavy goods vehicles (trucks with dolly or semi−trailer, and trucks with trailer). The questionnaire used an analogue scale, where respondents marked a point corresponding to the intensity of their assessment. Non−parametric tests were used (Friedman ANOVA and Kendall compatibility factor, U Mann−Whitney) in the statistical analyses. According to drivers, the most important road parameters in the site plan are the width of intersections (widened sections in the form of arcs that facilitate turning onto a perpendicular road), the proper location of log−yards, widened curves and the roadway width. Forest district employees pointed the width of intersections and the roadway as the most important. The road elements in the situational plan are regarded as more important by drivers of vehicles with dolly or semi−trailer compared to the drivers of vehicles with a trailer, which is caused by the differences in the parameters of these vehicles (turning radius). The most important road parameter in terms of the vertical structure is its gradual course (no steep ascents and descents). The respondents attach great importance to the significance of the type of road surface used, and indicated bituminous and crushed stone pavements as the most useful on transport routes in the forest. The importance of road parameters was rated significantly higher by drivers of high tonnage vehicles. However, it should be emphasized that despite the differences found, the answers of forest district road managers also indicate that they attach great importance to having the transport roads in the forest meet specific design requirements. In general the respondents considered the parameters of all analyzed road elements important – the importance of individual parameters was evaluated to from 5 to 6.5 out of 7 pts.
The aim of the presented research was to characterize the driving related to the deliveries of large−size Scots pine wood and to determine the factors affecting its structure and distance. Operation was divided in to: driving for load on a public and forest road, forest ride between loading points, as well as driving with saw logs on a forest and public road. Data on the distance traveled on forest and public roads (empty and with load), as well as, the number of loading places was determined on the data from drivers. In total, 1509 randomly selected deliveries carried out over a period of twelve months from 40 forest districts were analyzed. Investigated transports delivered 44,336 m³ of large−size pine round wood to the sawmill. Most deliveries were made within 100 km from the plant. Within this radius, 83.87% of drives for load and 75.35% drives with load were completed. The average distance for driving for load on a public road was 60.6 km, with the range from 0.5 to 205 km. The average driving distance with load to the sawmill was 70 km, the shortest distance 2 km and the longest – 238 km. Driving distances on forest roads, for and with load, was on the similar level of 3.5 and 3.4 km, respectively. The average distance in the forest, between loading points was 3.1 km, with SD=2.9 km, maximum 16 km. The largest share, 51.4% of total delivery distance, was related to driving with saw logs on a public road and depends on how many places in the forest the wood was picked up. In 36% of all deliveries, saw logs were loaded from two or more places, which involved additional drive on forest roads at the distance of 1,652 km. The analysis did not show statistically significant differences between driving depending on the season of the year. The stable wood supply during 12 months period, shows that large stocks of round wood to secure productions during sensitive periods (winter), is not needed.
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