Analysis of Dynamic Characteristics of One-way and Crossways Beam String Structures

摘要

Beam string structure (BSS) is a new kind of hybrid system, which has been widely used in long-span steel structures in the last decade. By using subspace iteration method, the dynamic characteristics of both one-way and crossways beam string structures have been investigated in this paper. Then the parametric analysis is further carried out to study the influences on the dynamic characteristics with different areas and pretensions of cable, various oblique angles and oblique rods for one-way beam string structure, and with a changed cable layout, i.e., broken layout for crossways beam string structure, etc. Research shows that the fundamental frequency of beam string structures is rather small and the vertical vibration mode is dominant, and the fundamental frequency of the one-way beam string structure equipped with oblique rods has significantly increased. Moreover, when the cable layout changes from parabolic layout to broken layout, with the increase of the height of the surrounding struts, the fundamental frequency of crossways beam string structure decreases slightly, etc. The conclusions obtained may be useful for the designers in similar projects.