Hybrid structures as a means of reducing - Analyzing the possibility of decreasing CO2 emissions by introducing more timber in the design of high-rise buildings
Examensarbete för masterexamen
The construction and building industry is a large emitter of carbon dioxide. A lot of work has been done as an attempt to reduce the emissions from the user stage of buildings. In recent years, there has been an increased interest in also reducing the emissions from the construction phase. Sweden aims to be carbon neutral by the year 2045. As part of that, the interest in timber and hybrid construction is increasing. The purpose of this thesis is to analyze if global stability can be ensured in high-rise buildings when implementing timber instead of concrete or steel and to check what impact these implementations have on the CO2 emissions. The study was conducted in two steps. The first is a literature study including arguments for and against hybrid structures, available modern timber products and different stabilizing systems. The second step is a case study performed on two different reference buildings constructed by Skanska. First the potential to reduce the mass of the buildings while maintaining the stability is controlled. Then the models are verified and new components are designed to be implemented into the buildings. After that new stability analyses are done to see if the buildings remain stable with the new hybrid structural systems. Finally, the potential reduction of CO2 emissions from using hybrid components is calculated and cost implications are discussed. The results show that it is possible to use timber and hybrid components instead of concrete and steel while maintaining the global stability. All components included in the study could be exchanged but it is shown that it is almost a prerequisite to implement some kind of light-weight floor to be able to also exchange the vertical load-bearing elements. Exchanging the floors creates a significant reduction in of CO2 emissions due to the big area, but it is shown that exchanging the steel members creates a bigger relative decrease.
Hybrid construction , Timber , Carbon dioxide , Engineered wood products , Sustainable construction