桩基支撑的塔式起重机在软粘土桩基中的地震响应分析（英文）

Seismic Response of Tower Crane Supported by Pile Foundation in Soft Clay

临时结构房屋的抗震性能次于永久结构房屋。桩基支撑的塔式起重机是一种临时结构,常被应用于建造高层建筑。安装在高处的塔式起重机,因其是高柔结构,在强地震动的作用下很可能会产生剧烈震荡。桩基结构的地震响应特性受周围的地基和基础类型的影响也较大。在当前日本的设计规范中,地震荷载仅仅被定义为20%的起重机结构重量,都没有充分考虑待结构的动态不稳定性和周围的地基类型。为探究塔式起重机在软粘土桩基中的抗震特性,开展了一系列的离心振动台试验。为起重机吊臂制定了2种不同的荷载条件来准确地模拟实际情况。根据测试结果,对塔式起重机的动力响应行为和影响的因素进行了讨论,得到如下结论:起重机臂架的荷载条件对桩的损伤程度有显著影响,并可以导致塔式起重机不同的破坏模式。

Earthquake resistance of temporary structures is inferior to that of permanent structures. A tower crane supported by a pile foundation, which is one of the temporary structures, is often used when constructing high - rise buildings. The tower crane installed in a high position may be vibrated largely by strong seismic ground motion because of its slender struc- ture. Dynamic response characteristics of the structure with a pile foundation are greatly influenced by the surrounding ground and the foundation type as well. In current Japanese design mode, however, the seismic load is only to be defined as 20% of the weight of a crane, neither dynamic unstability of the structure nor influence of the surrounding ground type is suffi- ciently considered. In this paper, a series of centrifugal shaking table tests was performed to investigate the seismic charac- teristics of the tower crane supported by a pile foundation in soft clay. Two different weight conditions were set for the crane jib to accurately simulate practical situations. From the test resuhs, the dynamic behaviours of the tower crane and the influ- enced factors were discussed. In addition, it was concluded that the weight conditions for the crane jib give significant influ- ence on the level of pile damage and might lead to different failure patterns of the tower crane.