Study on general dynamic amplification factor spectrum of ATC tower equipment using genetic algorithm
Xin Huang,Ruo-yu Zhang,Yang Lyu,Kun Wu,Yu Chen
Abstract
It is essential important to ensure the seismic safety of the airport traffic control (ATC) tower equipment. To provide dynamic parameter for simplified calculation of earthquake action of equipment, the floor acceleration amplification factor (FAA) along the height of the tower is analyzed. Meanwhile, floor response spectrum (FRS) of the tower equipment under frequent, fortification and rare earthquake action are established respectively, and the influence of the equipment's floor height on the FRS is investigated. By comparing the dynamic amplification factor spectrum between existing codes and tower equipment, a multi-segment target spectrum of the ATC tower equipment is proposed. Finally, a general dynamic amplification factor spectrum of the tower equipment is established by using genetic algorithm to optimize multi-segment target spectrum. The results indicate the distribution of the tower FAA is an S-shaped variation with increasing height of ATC tower. For the lower and middle floors, the FAA values align with those specified in Eurocode 8, while the upper floors are consistent with the Chinese GB 50011-2010 standard. The structure has a filtering effect on the frequency of earthquake waves, and the frequency of floor waves gradually approaches the natural frequency of the structure. The FRS of the tower has two peak values near the first and third periods of the structure, and the peak value of FRS at the first period under rare earthquake can reach 3 to 4 times that under frequent earthquake. The FRS in the upper functional areas increase with height, with a peak increase of approximately 10% between adjacent floors. The general dynamic amplification factor spectrum derived via the genetic algorithm closely matches the tower's dynamic amplification factor spectrum, particularly at peak points and in the descending segments, and the difference at the first and third-period points under frequent earthquake are 5% and 11%, respectively.
