Smart film crack monitoring method, which can be used for detecting initiation, length, width, shape, location, and propagation of cracks on real bridges, is proposed. Firstly, the fabrication of the smart film is developed. Then the feasibility of the method is analyzed and verified by the mechanical sensing character of the smart film under the two conditions of normal strain and crack initiation. Meanwhile, the coupling interference between parallel enameled wires of the smart film is discussed, and then low-frequency detecting signal and the custom communication protocol are used to decrease interference. On this basis, crack monitoring system with smart film is designed, where the collected crack data is sent to the remote monitoring center and the cracks are simulated and recurred. Finally, the monitoring system is applied to six bridges, and the effects are discussed. Introduction Bridges play a significant role in the economic development for the conveniences to the traffic and transportation. However, owing to the complexity of the force condition as well as the uncertainty of the surrounding environment, lots of unstable factors have been forced to the bridge after the construction, such that it is difficult to grasp the mechanical prosperities and behaviors during the operation. The frequently collapsed accidents of bridges endanger social well-being and stabilization. In view of the importance of bridge security, bridge health monitoring, especially in the field of crack monitoring, has made a rapid progress and become a hot topic in the current research. Crack is a macroreflection of deterioration and lesion of concrete structures. Jul 3, 2018 - WisDOT Bridge Manual. 18.3.4.2.3 Dead Load Deflection (Camber) Criteria. Usb vcom port driver for samsung e2120 free download pc. 18.4.10 Longitudinal Reinforcement Tension Check. The total factored force effect, Q, must not exceed the factored resistance, Rr. Checking longitudinal slab reinforcement for crack control criteria. Bridge Deck Cracking Investigation and Repair Vidal Velez Vargas University of North Florida This Master's Thesis is brought to you for free and open access by the Student Scholarship at UNF Digital Commons. It has been accepted for inclusion in UNF Graduate Theses and Dissertations by an authorized administrator of UNF Digital Commons. Due to crack propagation [], secondary diseases can be caused, such as leakage, corrosion of steel bars, and concrete carbonization, further affecting normal usage and the safety of the structures. The point monitoring method [, ] places sensors individually at certain critical points on the structures to monitor crack. It can only be feasible when the critical points are predicted accurately. Unfortunately, in engineering practice, cracks do not always appear on the critical points owing to material-heterogeneity and calculation errors. Recently, distributed monitoring method, which based on the optical fiber sensor, has been introduced in structural crack monitoring [–]. It has the characteristics of large information transmission capacity, high transmission speed, and high sensitivity. However, brittle optical materials with the order of several meters in length and only micrometer in diameter are difficult to be glued on or embedded into structures. ![]() Meanwhile, coaxial cable distributed sensor with electrical time domain reflectometry (ETDR) technology is buried in structures to collect strain and crack signals [–]. Still, this method has potential defects in installation, reliability, and stability of signals. High-resolution camera lens make it available to monitor cracks by collecting real-time images of structures [–]. This method has a higher feasibility for short-term crack monitoring in a given small area, but it has difficulty in monitoring tiny crack. Smart film monitoring method is proposed by the authors from empirical analysis and engineering practice. Smart film, in which a great number of insulated enameled copper wires are embedded to form a coordinate grid, is glued on the surface of the structure. Electrical signal is sent from one terminal of each wire, and the signal at the other hand is simultaneously detected.
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