| Abstract | Wind-induced vibration is one of the serious problems for tall and slender buildings. The
vibration in sway mode may lead to high horizontal accelerations which can cause human discomfort.
In that case, dynamic dampers may be used to suppress the excessive vibration. However, the
analysis that can accurately determine the wind-induced response is extremely difficult. Therefore,
wind tunnel experiments using aeroelastic models are usually conducted to determine the
wind-induced vibrations.
In this study, the Pattaya Park Tower is selected as a case study because the geometry of this
tower is rather unusual and preliminary calculations indicate that the acceleration at the top floor
may exceed the acceptable limit.
Wind tunnel experiments consist of ( 1) reasonable simulation of natural wind characteristics,
(2) reasonable simulation of dynamic prope1ties of building by a scaled model, and (3) measurement
of wind-induced response. With these simulations, the complex interaction between air flow and
structural vibration, i.e., aeroelastic effect, is automatically taken into account, so that the responses
can be measured directly from the model.
To determine the representative type of boundary layer flow, data of natural wind
characteristics at Pattaya site pas been collected and analyzed. This type of boundary layer flow
was then simulated in the tunnel by using spire, roughness arrays, and barrier elements. For the
simulation of building, a spring-mounted rigid model was employed. Two accelerometers were
attached to the model to directly measure the acceleration responses.
The measurements indicated that across wind acceleration is higher than along wind
acceleration in most cases, and this is due to the resonant effect of periodic vortex shedding wakes.
The acceleration response even exceeds the acceptable limit. Therefore, the use of dynamic damper
to suppress the vibration is suggested. |