Master theses spring term 2017

Master thesis offers from the Division of Building Materials

# 2016:1

Light timber frame floor structures

The aim of this project is to perform a comparative study between available fire-resistance calculation methods (given in Eurocode 5 and the European guideline for fire safety in timber buildings) specifically for light frame floor structures and test results from the database at RISE, the Research Institute of Sweden (former SP).

The work will involve, among other things:

  • assessment of the reliability of available data
  • approximation of missing parameters if possible (usually the strength of timber is unknown).
  • a comparative study between calculation results and test results using statistics.

# 2016:2

Failure times of gypsum boards

Fire protection usually falls-off the structure after a certain period of fire exposure. The structure behind it becomes unprotected after this point and generally experiences a period of increased fire exposure. In the current regulations an empirical equation is used to predict the time at which this occurs. In this equation the time to failure is only dependent on the thickness of the gypsum board. However, this method can be presumed to be oversimplified. Gypsum contains water, which slows down the heat transfer through the structure (as water requires a lot of heat to evaporate).

However, evaporation of water is also the main reason for shrinkage and cracks. Cracks around the fasteners are usually identified as the cause of gypsum failure. In light timber frame structures, distances between fasteners of gypsum boards are directly related to the distance between the joists they are attached to. One hypothesis is that the crack width in a fire is smaller when the joist (or screw) distances are smaller, which increases the failure time. Therefore, it is desired to determine a relationship between the failure time, the board thickness and the joist (or screw) distance.

The work would involve, among other things:

  • assessment of the reliability of available data
  • development of a simple analytical 1-dimensional model to estimate the crack width and an attempt to relate it to real gypsum failure times.
  • determine a relationship between a) gypsum failure times b) gypsum board thickness and c) joists and screw distances.

# 2016:3

Cavity barriers

Cavity barriers are needed to stop fires from spreading inside voids. Previously, this type of fire spread has caused high-damage fires, as the fire service cannot easily find and extinguish this type of fires. SP Fire research has developed a new method to assess fire stops. The plan is to perform a test of similar specimens. However, this time the to study different details such as the connection between fire stops.

The work would involve, among other things:

  • preparation of test specimens (preparations for temperature and oxygen measurements)
  • helping to perform the fire test
  • try a distinguishment method without using much water aIer a fire test (op2onal)
  • try to identify a method for the fire service to locate the fire during the test (op2onal).
  • produce some guidelines for the installa2on of fire stops in buildings.

# 2016:4

Lbrick / Combrick

Investigation and description of different prototypes for utilisation in toys, model kits and structural applications in different scales of a newly invented modular concept based on different material options – concrete, plastics, metal, wood, and composite materials with graphen for improved performance.

Lbrick is a patented building system and the project is proposed in collaboration with Leading Brick Building Systems.

# 2016:5

Investigating composite and material hybrid concepts

Combinations of materials have been utilised in construction throughout history. However, the combination of materials for synergic effects such as co-action is not as common. Many different concepts have been invented and introduced on the market, also in Sweden, for use in the construction sector. Few have survived.

This master thesis project is intended to focus on made attempts to launch different hybrid concepts, the aimed at effects and benefits, the marketing process and the factors enabling the concepts and products to survive on the market and an investigation of why others have disappeared.

The project aims at providing a basis for future projects on material and product development making use of different material properties in combination.

# 2016:6

Developing building components for computer/robot aided building production

The recent steps of development of CAD CAM, CNC and other processing tools in industrial building production has a big unexploited potential of saving resources (materials and energy). The capacity is so far mainly used in the industry to increase the time saving and economic benefits to a limited extent and the full capacity of decreasing the environmental footprint has not been explored.

This project aims at proposing new types of building products and components that make optimized use of the available means of production with improved resource utilization. The project aims at proposing design concepts, which are to be developed and proposed in contact with the building industry and timber product suppliers.

Issues to be considered:

  • Optimised material use and material combinations
  • Multi-functionality of materials and building components
  • Analysis of design parameters for an improved design and production process

# 2016:7

Strength properties of Thermowood decking

Stora Enso Industrial Components produces spruce and pine Thermowood in Finland and Latvia. A significant proportion of the material is used for decking where the flatwise bending strength and stiffness is critical for the performance.

The thesis project aims at determining the resulting strength properties of Thermowood decking after heat treatment of material of different dimension and raw material quality.

The project is proposed in collaboration with Stora Enso Industrial Components.

# 2016:8

Finger jointed and laminated Thermowood components

Stora Enso Industrial Components produces finger jointed and laminated window components made from Thermowood. The heat treatment process has negative effects on strength and brittleness of the material. Many studies have been aimed at the impact of heat treatment on sawn timber and small clearwood samples. However, these studies have mainly been made on material treated at maximum temperature 212 °C or higher. Less is known on the effects on strength when the wood is treated at milder climates, and very few studies have been aimed at finger jointed or laminated products.

The thesis project aims to determine the bending strength and brittleness of softwood heat treated at maximum temperatures 190 °C and 212 °C, and to compare the strength values with untreated reference wood. The study may possibly include sawn dimensions, finger jointed material, and laminated beams.

The project is proposed in collaboration with Stora Enso Industrial Components.

# 2016:9

Re-engineered Thermowood

Stora Enso Industrial Components produces spruce and pine Thermowood in Finland and Latvia. The relatively costly process makes it important to utilize also material that has been downgraded after treatment. The thesis project aims at re- engineering of suitable downgraded goods by defect elimination and finger jointing.

The thesis project aims to determine volumes available for re-engineering, identify suitable processes for extraction of the material, defect elimination, and finger jointing. Pilot scale re-engineering shall be made and both visual appearance and strength properties of the resulting material shall be determined. An assessment of the product cost shall be made.

The project is proposed in collaboration with Stora Enso Industrial Components.

# 2016:10

Effect of the freshness of wood material surfaces on surface treatments of wooden panels

Today, industrial paint treatments become more and more common due to benefits from faster assembly on site and more even quality of the paint layer.

This project aims at a study of the properties of the wood surface and the potential effects of the freshness of the wood surface on adhesion of applied surface treatments.

The project aims to study different paint types and the effects of time after cutting. The project comprises lab test practice for verification of the effects from contamination of the wood surface.

The project is proposed in collaboration with SP Sustainable Built Environment.

# 2016:11

Element detailing for efficient timber construction

In the timber house producing industries a well-defined technical detail fixed on site steers the assembly of the wall elements. A steering batten in wood is applied on the concrete slab in before hand and it might get affected by moisture and weathering, before the wall elements are placed, depending on the time it is left exposed.

The steering detail is crucial for the assembly of the prefabricated house and is in focus for this development and innovation project aiming at solving the problem by looking at new possibilities to produce this detail with other material alternatives and a new improved design.

 This project on facade technology is proposed in collaboration with Svenskt Trä, part of the Swedish Forestry Industries Federation (Skogsindustrierna).

Additional subjects of current interest for the industry:

  • Suitable façade systems for timber houses. Life Cycle Cost perspective on technology, moisture, fire, production and market analysis.
  • Decreased total energy consumption and maintenance for timber-based construction of multi storey residential buildings aiming at considering technology, environmental effects and costs.
  • Estimation of energy consumption and flow in buildings. Study of why many softwares for calculation give higher energy consumption values for timber than experienced in reality, compared to buildings based on other structural materials.

Master thesis offers Building Materials spring 2017 (pdf 84 kB)

Contact persons:

Magnus Wålinder

Andreas Falk

Belongs to: Department of Civil and Architectural Engineering
Last changed: Oct 18, 2016