Active control experiments on a herringbone ribbed cable dome

Abstract

Active control experiments on a newly proposed herringbone ribbed cable dome are described in this study. The cables of the dome are designed to have the ability to change length in order to adjust the geometrical configuration and the force distribution of the structure. Thereby, the dome is adaptable to different load cases. To begin with, for achieving the control amount for the active control test, an active control algorithm based on a nonlinear force method is presented. Then, an assembly and pre-stressing procedure is implemented. Active adjustment tests on three possible types of adjustable cables are performed to provide a practical method for the following active control test. The active control test demonstrates the applicability of the active control algorithm to achieve both force control and shape control. The method can be used to prevent failure of the cable domes due to slackening of the ridge cables and excessive displacements of the central section of the cable dome. The experiments verify the proposed control algorithm and the feasibility of the cable dome to adapt to excessive full span load and maintain the integrity of the structure.

摘要

目 的

本文选取一大型肋环人字型索穹顶结构模型为试验对象进行主动控制试验研究, 验证主动控制方法应用于索杆张力结构的可行性。

创新点

• 1. 提出通过改变索杆张力结构的形状来提高结构承载性能的方法, 并基于非线性力法提出索杆张力结构形状控制和内力控制的计算模型。

• 2. 设计具有长度可调拉索单元的肋环人字型索穹顶模 型进行主动控制试验研究, 并将结构响应的试验结果与理论计算结果进行对比。

方 法

• 1. 以结构形状和杆件内力为控制目标建立求解主动单元调控量的计算模型, 编制计算程序进行主动单元调控量的计算;

• 2. 通过对具有拉索长度可调单元的肋环人字型索穹顶进行模型试验研究, 考察结构主动调控过程和主动控制过程的结构响应情况。

结 论

• 1. 基于非线性力法推导索杆张力结构的结构响应计算公式, 推导结果可应用于结构主动控制的计算中;

• 2. 对具有拉索长度可调单元的肋环人字型索穹顶进行模型试验研究, 结果表明利用本文提出的理论方法得到的控制方案可达到所设定的结构控制目;

• 3. 试验值与理论计算值数据吻合良好, 验证本文理论计算模型的正确性和应用于实际结构的可行性。