@misc{9242995,
  abstract     = {{This thesis investigates how material use in cast in situ concrete slabs and walls for multi-storey residential buildings can be reduced by separating the load-bearing concrete from functions that do not have to be solved within the structural member itself. The study is motivated by the high climate impact of concrete construction and by indications that material use in concrete structures has increased over time despite improved materials and more advanced design methods.

The work combines a review of Swedish design practice, regulations and reference structures with parameter-based structural calculations. Two cast in situ residential structures in Lund were used as references: Cykelskrapan from the 1950s and Troja from contemporary practice. Slab alternatives were evaluated using one metre wide slab sections idealised as beam strips, with checks for load-bearing capacity, deflection, crack width and vibration. Wall alternatives were analysed as vertical wall strips under eccentric compression, including reinforced and unreinforced cases with second-order effects.

The results show potential for material reduction in both slabs and walls. For slabs, several analysed alternatives reached larger or comparable spans with a smaller structural concrete thickness than the contemporary reference slab, while still satisfying the adopted structural and serviceability checks. Higher concrete strength alone did not provide a general path to material efficiency. For walls, axial resistance was governed mainly by thickness and effective buckling length, while increased distributed reinforcement had a smaller influence. The wall comparison also showed that many compression dominated wall strips can reach sufficient axial resistance without reinforcement within the adopted limits.

Overall, the study shows that material use in cast in situ concrete structures can be reduced when the role of the load bearing concrete is defined more narrowly. Instead of using the concrete member to solve structural performance, acoustic performance, fire protection and installations at the same time, the results support a design approach where the concrete is used primarily for its load-bearing role. Other building functions should then be handled separately and assessed at system level.}},
  author       = {{Wedervang, Lukas and Sten, Karl}},
  language     = {{eng}},
  note         = {{Student Paper}},
  series       = {{0349-4969}},
  title        = {{Rethinking Cast in Situ Concrete Structures: A Study of Material Use in Residential Slabs and Walls}},
  year         = {{2026}},
}