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10397 Uppsatser om Wood-based beams - Sida 11 av 694

Död ved i vatten - funktionella strukturer och dess påverkan på öring (Salmo trutta, L.)

The background to this work was to see if there was a connection between large woody debris (LWD) and the presence of brown trout in our Swedish forest streams. Previous researches by Degerman et al. (2004) have shown that there is a strong correlation between the amount of dead wood and the presence of brown trout. The goal was then to find a way to restore, maintain and increase the trout habitats by constructing and adding manmade wooden structures that would mimic natural deadwood and its features in flowing water. The inspiration was partially taken from a water restoration program in the Klamath River of northern California, USA.

Experimentell undersökning av provkroppar för trälimfogar

This thesis engages the topic of test methods for wood adhesives. Two test methods were evaluated, EN 302-1, a European standard, and ASTM D905, an American standard. The total amount of specimens manufactured and tested was more than 500. The adhesive bonds were tested in shear with an increasing load on the specimen until failure.The adhesives used were epoxy-resin, phenol-resorcinol-formaldehyde and a 2-K polyurethane. The test programme included five different types of intentional errors per method, in order to investigate the sensitivity of the test methods.

Förändrad aptering av massaved från 3- till 4-meterslängder vid gallring inom Södra : en systemanalys av effekter från avverkning till levererad virkesråvara

The costs of logging and of transportation with truck are dominating the total cost of wood delivered at industry. To support the profitability for the members' forestry the processing and handling with the timber has to be as efficient as possible. Increased length of pulpwood in thinning is one conduct that can result in higher productivity and/or lower costs. The study is scaled as a system analysis with the aim to exemplify the differences between working with 3- and 4-meter as standard length of pulpwood, related to biological aspects, timber receipts, cost of logging and cost of transportation with truck. Important aspects are if the change is technically and biologically feasible and economically profitable.

TOMO Hugglink

Tomo Hugglink (TOMO Skog) is an innovation for harvest and transport of biofuels. The system consists of a truck, a chipping unit and crane mounted on a link and a wood chip trailer. The system works in such a way that the chipping unit is disconnected and placed on the site and wood chips are loaded directly into the wood chip trailer.The aim of this study was:- To examine the performance of the TOMO Hugglink system under different conditions such as the size, placement and quality of the pile.- To calculate the cost per raw ton for two vehicle combinations at different transport distances and to examine the effect of a reduction in set-up time and an increase in load weight.- To identify possible improvements with the TOMO Hugglink system.A time study was conducted within the thesis work to make it possible to determine production and time consumption. In the subsequent economic analysis the cost per tone at different transport distances was calculated for two different lorry concepts. Furthermore the effect of a reduction in set-up time and an increase in load weight was calculated.Under current conditions the utilization of the chipper is low and only 29 % of the total system time is occupied by chipping.

Förbränning av pellets framställda av defibrerad granråvara :

Fuel pellets are in Sweden mainly produced from sawdust and cutter shavings. Before the pelletising process the raw material is dried to attain consistent moisture content and ground up in a hammer mill. In the densification process (pelletising) the ground material is forced through holes in a rotating die. This heats up the wood particles which cause them to soften and self bond. After the process the pellets are cooled, sieved and bagged. The milling process creates a wide range of particle sizes.

Utvärdering av den bärande tegel- och betongstommen i en byggnad från år 1916

This Master thesis is about a postal- and telegraphic building in Eskilstuna, Sweden. The construction methods for the specific building and buildings in general from the same time are described. The purpose of the report is to describe the loads acting on the building and how it has been built and why it has been rebuilt during the years. After this, possibilities of reconstruction and adaptation for today?s demands can be evaluated.

Alla vill beta men ingen vill bränna : skogshistoria inom Särna-Idre besparingsskog i nordvästra Dalarna

In this work I have tried to reconstruct the forest history within Särna-Idre forest common in northern Dalarna from the 19th century until present time. The Särna-Idre region has been an extensively used landscape for a long time. Pollen which indicates grazing has been found in samples orginating from the 10th century. Early travellers from the 18th and 19th centuries seem to have been passing trough a "used" landscape. Burned forests on naked ground are described as common. Also large areas are mentioned as undisturbed with lots of large trees, snags and dead wood.

Edward Scissorhands : En genusanalys

Syftet med denna uppsats är att analysera mansbilden av karaktären Edward i filmen Edward Scissorhands (Tim Burton, 1990). Genom attstudera hans personlighet och egenskaper ur olika perspektiv, som kan uppfattas som både manligt och kvinnligt, har jag försökt att ta reda på vem denna utstickande karaktär är.Med hjälp av genusteorier och jämförelser av tidigare filmatiseringar som Ed Wood (Tim Burton, 1994), Sleepy Hollow (Tim Burton, 1999) och The cabinet of Dr. Caligari (Robert Weine, 1920) har jag även kunnat fördjupa mig i mansbilden av Edward. Jag har dessutom fokuserat kring Tim Burtons säregna filmskapande, men också kring stjärnskapet hos Johnny Depp, skådespelaren som Burton ofta samarbetar med.Edward Scissorhands har visat sig vara en man med både manliga och kvinnliga attribut, vilket gör honom till en icke stereotypisk man som saknar hjältemod och en muskulös kropp. Trots det så tyder inget på att han är mindre man bara för att han har mer eller mindre egenskaper som generellt uppfattas som manliga.

Val av byggproduktionsmetod/ Praktikfall Klammerdamm : Golvgips eller avjämningsmassa

This report is about how to decide which method is the most suitable as floor covering at projectKlammerdamm in the centre of Halmstad. The covering has to be fire resistant and soundproof inorder to protect the wood structure and stop noise from traveling between apartments. There aretwo possibilities either traditional gypsum board or gypsum-based self leveling underlayment.The roads around the construction site are narrow. A regular twenty-five meter long truck has nopossibility to reach the site. The construction site is small and the storage area is limited.

Tillämpning av nya beräkningsmetoder för branddimensionering av  träkonstruktioner - analyser och jämförelser

To build high-rise buildings made of timber has for long been limited by national laws, due to the lack of knowledge in engineering solutions. Frame structures made of wood has for a long time been associated with major fire hazards and consequently lower safety and this connection is still being made today. The increased environmental awareness in recent years has contributed to the exploitation of indigenous building materials, including wood from our own Swedish forests and has become increasingly common. Increased knowledge about how structures behave in fire and how they can be protected in order to achieve safe timber structures has resulted in a growing interest in these structures in the construction industry. Research in the area is constantly updated and new laws allow any number of storeys in wooden buildings in Sweden as long as the performance requirements are fulfilled.The main part of this work has involved calculations of the fire resistance and load bearing capacity of floor and wall constructions.

Älgens barkgnag på granstammar : omfattning med avseende på geografisk utbredning, skadad volym och ekonomiska konsekvenser

In three areas in the province of Småland studies has been done to investigate how big damage the moose may do to P. abies. An inquiry examination and two different types of surveys were done to find out how big area, which volume and which financial consequences the moose debarking has had on the forest. When the volume was calculated the rot spreading was included. The area that was damaged was stipulated with the answers from the inquiry examination. 59 % of the asked forest owners answered the inquiry.

Bokhögstubbar i Klåveröds strövområde : utbredning, egenskaper och betydelse för rödlistade vedlevande skalbaggar

Lack of dead wood is the main cause of decaying or loss of populations for many forest species. To increase the amount of dead wood is a prerequisite to maintain biodiversity in forests of northern Europe. In summer 2006 the recreation area Klåveröd, at Söderåsen in Skåne, Sweden, has been inventoried for high stumps (snags) of beech, (Fagus sylvatica). The result of the inventory has been compared with data of the real estate and forest management directories from the owner, region Skåne. The results have also been matched with the results from an inventory of saproxylic beetles in 2005, performed with windowtraps on selected snags both in the area and the adjacent national park Söderåsen. 594 snags were found on 747 ha.

Metoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket, efter den senaste skogsvårdslagenMetoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket, efter den senaste skogsvårdslagen.

In 1994 a new Forestry Act was accepted in Sweden. One of the aims of the law is to raise consideration forpreservation of biodiversity. Since the new law got accepted and some time has passed, there now lie someinterest in examining whether the law has been effective towards its purpose. Methods suitable for analysishave been examined during this study. The content of this pilot study is based around five parameters whichcan be used to validate the effects of the new law.

PEG-migration? MALDI-TOF-analys av beläggningar från fyra arkeologiska träföremål

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2012:29.

Numerisk simulering av jordtryck mot rörbro ? Med tillämpning av programmet PLAXIS

This thesis deals with numerical simulation of earth pressure against tubular bridges in the software Plaxis. Plaxis is a FEM (Finite Element Method) software based on numerical calculations for which approximate solutions are developed through an iterative process. The program is specifically designed for soil and rock mechanical tests, such as voltage and deformation calculations in soil.The Royal Institute of Technology conducted in 2005, field tests on tubular bridges of corrugated steel, which was part of Ersa Bayoglu Fleners PhD (Bayoglu Flener, 2009). She studied how two different tubular bridges deformed during installation and filling. Tests and measurements were made during filling.

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