The Performance of Tall Timber Buildings under Lateral Loads
(2024) In TVBK-5000 VBKM01 20231Division of Structural Engineering
- Abstract
- Pollution and its impact on the environment is one of the greatest problems facing humanity today. Since the building sector is responsible for 40\% of the total carbon dioxide emissions, it is important to investigate the sector to see how emissions can be reduced. Due to timber having a smaller impact on the environment compared to steel and concrete, it is of substance to investigate the possibilities of building with timber.
High-rise buildings are characterized by being built of steel and concrete, although there are some medium high-rise buildings made out of timber. As a material, timber is lighter and more flexible than steel and concrete which makes timber more prone to deflect due to loads. Therefore, it can be hard to meet... (More) - Pollution and its impact on the environment is one of the greatest problems facing humanity today. Since the building sector is responsible for 40\% of the total carbon dioxide emissions, it is important to investigate the sector to see how emissions can be reduced. Due to timber having a smaller impact on the environment compared to steel and concrete, it is of substance to investigate the possibilities of building with timber.
High-rise buildings are characterized by being built of steel and concrete, although there are some medium high-rise buildings made out of timber. As a material, timber is lighter and more flexible than steel and concrete which makes timber more prone to deflect due to loads. Therefore, it can be hard to meet the requirements for the serviceability-limit state when designing lateral stabilizing systems out of timber. On top of that, the connections between timber elements are also prone to deflect (slip) when affected by loads. To simulate the timber connections behavior, the connections are usually modeled with a low-stiffness spring.
The purpose of this thesis was to compare the behavior of several lateral stabilizing systems under static and dynamic loads. This was carried out in terms of static deflections and modal parameters.
The thesis consists of a background on the static- and dynamic behavior of high-rise buildings, timber as a building material, and a case study regarding the medium-rise building ”Mjøstårnet” located in Norway. The original structure is made out of glulam and is stabilized by truss-systems in the facade but alternative stabilizing systems are also investigated.
The results of static and dynamic behavior concerning wind load (both winds along the long- and short facade) showed that both design alternatives are valid regarding the deflection limit according to Eurocode. However, the modal analysis showed differences between the models, which could be of importance for the dynamic response. (Less) - Popular Abstract
- The interest in building high-rise timber buildings has risen in recent years, as has the importance of our climate on Earth. The building sector is responsible for a large portion of the total carbon dioxide emission to our atmosphere, therefore, it is important to find more sustainable ways of building. One way to accomplish this is to use timber instead of steel and concrete when constructing buildings, such as Mjöstårnet in Norway, a 14-story high-rise building completely built in timber. But the topic is still new and the already existing high-rise structures in timber are seen as unique. To increase the number of high-rise buildings in timber, more knowledge and references are needed to make this a reality.
As we all know, carbon... (More) - The interest in building high-rise timber buildings has risen in recent years, as has the importance of our climate on Earth. The building sector is responsible for a large portion of the total carbon dioxide emission to our atmosphere, therefore, it is important to find more sustainable ways of building. One way to accomplish this is to use timber instead of steel and concrete when constructing buildings, such as Mjöstårnet in Norway, a 14-story high-rise building completely built in timber. But the topic is still new and the already existing high-rise structures in timber are seen as unique. To increase the number of high-rise buildings in timber, more knowledge and references are needed to make this a reality.
As we all know, carbon pollution is one of humanity's greatest problems today, where the building sector is responsible for a large portion of the total pollution. Through replacing concrete and steel with timber, which has a lower climate impact, the total carbon pollution can be decreased; moreover, building taller buildings can house more inhabitants per area of the building compared to a building with fewer floors.
The results of this master's thesis indicated that a high-rise building built in timber can be stabilized against the wind by using timber beams or by utilizing timber glued together as walls so-called shear walls. This ensures that the structure can withstand deflections or movement caused by the wind. In the thesis, a case study was conducted consisting of three different models of the structure Mjøstårnet. One of the models replicated the stabilizing system of the real structure, using diagonal timber beams in the facade, and the two other models used timber walls in both the facade and in the middle of the floor plan to stabilize the structure. The three models showed that the structure was strong enough for all three design options to create a habitable building.
The increased variety of design options allows for more opportunities to create more suitable floor plans, enabling timber to compete with concrete or steel. In addition, these findings will add to the collective knowledge about this relatively new subject, especially when compared to steel or concrete. It is crucial to enhance our understanding since there is still skepticism about using timber, particularly for taller structures. Demonstrating the potential of timber can help increase confidence in building with the material.
By utilizing timber in high-rise buildings, the carbon footprint of the structure can be lowered since timber emits less carbon dioxide into the air than concrete or steel. Lowering carbon dioxide emissions benefits our society since this is one of the greatest problems facing future generations. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9175365
- author
- Arnebrant, Erik LU
- supervisor
- organization
- alternative title
- Reaktioner hos höghus med trästomme utsatta för horisontella laster
- course
- VBKM01 20231
- year
- 2024
- type
- H3 - Professional qualifications (4 Years - )
- subject
- keywords
- Timber, High-rise buildings, Dynamics, FEM, Modal Analysis, Wind Load
- publication/series
- TVBK-5000
- report number
- 5293
- ISSN
- 0349-4969
- language
- English
- additional info
- Examiner: Eva Frühwald Hansson
- id
- 9175365
- date added to LUP
- 2024-09-25 08:22:09
- date last changed
- 2024-09-26 11:25:36
@misc{9175365,
abstract = {{Pollution and its impact on the environment is one of the greatest problems facing humanity today. Since the building sector is responsible for 40\% of the total carbon dioxide emissions, it is important to investigate the sector to see how emissions can be reduced. Due to timber having a smaller impact on the environment compared to steel and concrete, it is of substance to investigate the possibilities of building with timber.
High-rise buildings are characterized by being built of steel and concrete, although there are some medium high-rise buildings made out of timber. As a material, timber is lighter and more flexible than steel and concrete which makes timber more prone to deflect due to loads. Therefore, it can be hard to meet the requirements for the serviceability-limit state when designing lateral stabilizing systems out of timber. On top of that, the connections between timber elements are also prone to deflect (slip) when affected by loads. To simulate the timber connections behavior, the connections are usually modeled with a low-stiffness spring.
The purpose of this thesis was to compare the behavior of several lateral stabilizing systems under static and dynamic loads. This was carried out in terms of static deflections and modal parameters.
The thesis consists of a background on the static- and dynamic behavior of high-rise buildings, timber as a building material, and a case study regarding the medium-rise building ”Mjøstårnet” located in Norway. The original structure is made out of glulam and is stabilized by truss-systems in the facade but alternative stabilizing systems are also investigated.
The results of static and dynamic behavior concerning wind load (both winds along the long- and short facade) showed that both design alternatives are valid regarding the deflection limit according to Eurocode. However, the modal analysis showed differences between the models, which could be of importance for the dynamic response.}},
author = {{Arnebrant, Erik}},
issn = {{0349-4969}},
language = {{eng}},
note = {{Student Paper}},
series = {{TVBK-5000}},
title = {{The Performance of Tall Timber Buildings under Lateral Loads}},
year = {{2024}},
}