In-situ experimental research on spectrum responses of broken wire of large diameter PCCP pipelines (Ⅰ)
Luo Jianjun1 Yao Xuande2 Zhang Dongsheng3 Liu Jiangning4
1. Tunnel and Underground Engineering Research Center of the Ministry of Education, Beijing Jiaotong University, Beijing 100044, China;
2. Beijing Institute of Water, Beijing 100048, China；
3. Key Laboratory of Fiber Optic Sensing Technology and Information Processing of the Ministry of Education, WUT, Wuhan 430070, China;
4. Beijing Hanjian Heshan Pipeline Co., Ltd., Beijing 102423, China
Abstract：For the large water conservancy project to divert water from the South to the North in large diameter PCCP pipeline which is vulnerable to a variety of external and internal factors, not quickly and accurately determine broken position is the difficulty of PCCP.PCCP pipeline structure broked wire is tested in the field. Based on the in-depth study on the structure and the broken wire mechanism of large diameter PCCP pipelines, a new broken wire detection technology based on frequency change by the fiber Bragg grating sensors is proposed. The feasibility, reliability and practicality of the system proved by the in-site tests. Meanwhile, the real-time monitoring of large diameter PCCP pipelines can be fulfilled by the detection system. It is found that before and after the pipeline wire breaking, the response spectrum is same when it is impacted in different locations. And the spectrum is not same when different objects are impacted, but a predominant response will emerge near 830Hz. Regardless of the broken wires, impact locations and impact styles, m three spectral peak response range will be formed. Before and after the wire breaking, the first and the third frequency range is basically the same. But for the second predominant peak, the spectrum range before the breaking is between 290Hz and 380Hz, while that after breaking is between 500Hz and 650Hz. The proposed method can be used in qualitative and quantitative analysis of wire breaking in the PCCP pipelines, so it can provide guidance for repair practice.
骆建军 姚宣德 张东生 刘江宁. 大口径PCCP管道断丝频谱响应现场试验研究(Ⅰ)[J]. 土木工程学报, 2016, 49(9): 110-116.
Luo Jianjun Yao Xuande Zhang Dongsheng Liu Jiangning. In-situ experimental research on spectrum responses of broken wire of large diameter PCCP pipelines (Ⅰ). 土木工程学报, 2016, 49(9): 110-116.
