近年來,我國經濟蓬勃發展,都會地區超高層建築物需求日增。超高層建築物的施工期長,其中進行高層吊裝作業之固定式起重機的揚程高、構件重、體積龐大、吊運次數頻繁、且施工範圍經常涵蓋整個工地,受到地震力的影響時,極可能釀成工程災害。目前國內對於施工中臨時設施在耐震方面之規定尚不完善,為了解地震力對超高層建築物施工期間起重機之影響,本論文中針對建築物在不同施工階段之結構特性進行結構動力分析,以探討起重機在各種情況下之力學行為,並依分析結果探討以起重機錨定位置之加速度反應譜作為其地震力計算基準之可行性。最後根據結構動力學原理,使用調整起重機結構之勁度及質量分布等方式,以達降低起重機所受之最大地震力之目的。
All investigation on the seismic behaviors of crane structures was conducted following the collapse of two tower cranes during the construction of the 101-story Taipei financial Center in the 2002 Hualien(331) Earthquake originated 44 kilometers off the east coast of Taiwan. Analysis was carried out on computer models representing various construction stages of typical tall building structure through both response spectrum and time-history analyses to estimate the possible seismic load that would be inflicted on the crane structure. A comparison was made between results of these two approaches to verify that whether the spectrum analysis is able to yield an accurate result based on acceleration record obtained at the location where the crane was mounted. The result of this analysis showed that in the absence of eccentricity, the spectrum method was able to produce satisfactory results while requiring minimal calculation. However, if the crane was allocated away from the center of rigidity, a twisting motion may take over the vibration of building, which would affect the accuracy of the spectrum method.