Abstract:
The structural efficiency of tall buildings significantly relies on the lateral stiffness of
building and its resistance capacity against lateral loads. However, when the structure
becomes taller and slender, the building responses under wind loads become more
pivotal as it reduces structural stiffness of building. Therefore outrigger and belt truss
structural systems that connect through the central core system and the most exterior
columns in building are often introduced in high rise structures to provide adequate
lateral stiffness in order to control the wind deflection and drift criteria in acceptable
limits. Most research works are limited to building with outrigger systems of
concrete material, consisting of simple square and rectangular shaped building plan
layouts having vertical regularity. Only few studies were based on a single model
under different patterns of outrigger structural systems to identify the optimum
outrigger structural system when outrigger arrangements are varied. This study aims
to bring a broader understanding of both conventional outrigger & virtual outrigger
systems by identifying the most efficient lateral load resisting outrigger system for a
reinforced concrete high rise building under different outrigger structural materials of
concrete, steel and composite by comparing the performance for three different
outrigger arrangements; only outriggers, only belt truss and combination of both
outrigger and belt truss when subjected to wind loads while their positions remain
constant for all the three cases. The structural performance was evaluated based on
building frequency, wind induced lateral displacement at top storey and inter storey
drift ratio and results demonstrate that addition of outriggers and belt trusses of
different structural materials have significantly enhanced the structural performance
of building against wind action and the best form of outrigger structural arrangement
is varied based on each structure material.
Citation:
Nissanka, N.A.A.C. (2022). Effectiveness of various outrigger systems under different structural materials for a reinforced concrete high rise building subjected to wind loads [Master's theses, University of Moratuwa]. Institutional Repository University of Moratuwa. http://dl.lib.uom.lk/handle/123/22500