Base isolation systems Sự biệt lập thuật ngữ dùng để chỉ mức độ tương tác giữa các đối tượng. Một đối tượng được cô lập nếu có sự tiếp xúc trao đổi với các đối tượng khác. Các hành động của cô lập một đối tượng liên quan đến việc cung cấp một giao diện giữa các đối tượng và các nước láng giềng làm tối thiểu tương tác. Những định nghĩa này áp dụng trực tiếp vật lý khác nhau hệ thống. Ví dụ, người ta nói về cô lập một phần của thiết bị từ của nó hỗ trợ bằng cách gắn các. | 337 Chapter 5 Base isolation systems Introduction The term isolation refers to the degree of interaction between objects. An object is said to be isolated if it has little interaction with other objects. The act of isolating an object involves providing an interface between the object and its neighbors which minimizes interaction. These definitions apply directly to various physical systems. For example one speaks of isolating a piece of equipment from its support by mounting the equipment on an isolation system which acts as a buffer between the equipment and the support. The design of isolation systems for vibrating machinery is a typical application. The objective here is to minimize the effect of the machine induced loading on the support. Another application is concerned with minimizing the effect of support motion on the structure. This issue is becoming increasingly more important for structures containing motion sensitive equipment and also for structures located adjacent to railroad tracks or other sources of ground disturbance. Although isolation as a design strategy for mounting mechanical equipment has been employed for over seventy years only recently has the concept been seriously considered for civil structures such as buildings and bridges subjected to ground motion. This type of excitation interacts with the structure at the foundation level and is transmitted up through the structure. Therefore it is logical to isolate the structure at its base and prevent the ground 338 Chapter 5 Base Isolation Systems motion from acting on the structure. The idea of seismic isolation dates back to the late nineteenth century but the application was delayed by the lack of suitable commercial isolation components. Substantial development has occurred since the mid 1980 s Naeim and Kelly 1999 and base isolation for certain types of civil structures is now considered to be a highly viable design option by the seismic engineering community particularly in Japan .
