Abstract
A prestressed bolt connection is one of the crucial connection types in timber structures. The daily checking and maintenance of bolt connections have to be carried out in order to avoid the collapse of timber structures due to bolt looseness. Real-time health monitoring of bolt connections can not only reduce the daily maintenance cost of timber structures, but it can also avoid property loss and casualties by giving early warning if the bolt connection is loosened in timber structures. This paper proposes a method of prestress monitoring of bolt joints in timber structures by pasting lead zirconate titanate (PZT) patches on the surface of timber structures, and the time-reversal method is applied to denote the connection status of bolts in timber structures. The prestress loss index of timber structural bolts based on wavelet analysis is designed to quantify the bolt looseness of the timber structure. The experimental timber specimen was fabricated consisting of two timber panels, one bolt, and two PZT patches. One of the PZT patches acted as an actuator to emit the stress waves, and another one acted as a sensor to receive the stress wave propagating through the connection interface. The experimental results showed that the amplitude of the focused signal increases significantly with the increase of the prestress value of the bolts, which verify that the proposed method can be utilized to monitor the looseness of bolts in timber structures. The analysis results of the focused signal is proof that the prestress loss index of timber structural bolts designed based on wavelet analysis can reflect the looseness of timber structural bolts.
Highlights
The timber structure has traditionally been a symbol of ancient architecture, which has a long history of evolution
This paper proposes a health monitoring method for the bolt connection in timber structures based on pasting lead zirconate titanate (PZT) transducers
The PZT patches were pasted on the surface of the timber structure specimen, combining with the piezoelectric ceramic active sensing technology and the time-reversal method to monitor the looseness of the bolts of the timber structure in real time
Summary
The timber structure has traditionally been a symbol of ancient architecture, which has a long history of evolution. From the palaces and temples of monarchs to the houses and pavilions of people, there are many timber structures that still survive and are widespread. With the advancement of social science and technology, the timber structure has joined the elements of industry and has become a collection of traditional structural systems with modern science and technology [1, 2]. With the continuous optimization of timber structure design, the use of metal material connectors in the design of contemporary timber structures has gradually increased, and it has been extensively used in the design of connection nodes. Acting in accordance with relevant research, nearly 80% of damaged timber structures failed because of the destruction of node connections [3]. In order to reduce or even avoid the economic losses caused by the looseness of the bolts of a timber structure, it is of great significance to find an effective method to monitor the looseness of the bolts of a timber structure in real time, and give an early warning of the bolt prestress loss
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
