Device and method for width monitoring and regional self-positioning of tensile fracture of concrete

Abstract

The invention, which belongs to the technical field of civil engineering, provides a device and method for width monitoring and regional self-positioning of a tensile fracture of concrete. The devicecomprises a direct-current voltage-stabilizing power supply, a fixed-value resistor, an external conductive electrode, internal conductive electrodes a1, a2. . . ., an-1, and an, a concrete component,a voltage conversion module, and a computer. The external conductive electrode and the internal conductive electrodes are arranged at a tensile area at the bottom of the concrete component. The external conductive electrode is connected in series with the fixed-value resistor and is connected with positive and negative electrodes in the direct-current power supply; and the two ends of the fixed-value resistor are connected with the voltage conversion module. The internal conductive electrodes ai and a (i+1) are connected to the voltage conversion module. The voltage conversion module is connected to the computer through a data acquisition device. Acording to the invention, the resistance change rate of the concrete target area under the load effect is monitored in real time to realize self-monitoring of the width of the concrete fracture and positioning of a fracture occurrence area. No fracture sensor needs to be arranged at the component additionally and adding of lots of conductivematerials in the concrete base is avoided; and the real-time monitoring of the fracture of the important concrete structural component is guaranteed.

Description

technical field [0001] The invention belongs to the technical field of civil engineering, and relates to a device and technology for self-positioning of cracking areas of concrete components and self-monitoring of crack width changes. Background technique [0002] Concrete has good compressive strength and mainly bears compressive stress in the structure, but the tensile performance of concrete is low, and its tensile strength is only about one tenth of the compressive strength. The tensile zone of concrete structural members works with cracks in the normal use stage, and the continuous expansion of cracks under the load will weaken the effective section of the member and directly affect the deformation, durability and bearing capacity of the structure; so the concrete Real-time tracking of cracks is of great significance. At present, the crack detection and monitoring technologies widely used in concrete structure engineering mainly include: manual detection, ultrasonic, a...

AI Technical Summary

Problems solved by technology

However, at present, the strain self-sensing technology of cement-based composite materials at home and abroad cannot realize the judgment and real-time monitoring of the cracking position and crack width of concrete cracks. Conduct scientific assessments of safety and security, and influence the repair and reinforcement of damaged structures

[0004] Concrete is a poor conductor of electricity. The existing cement-based material strain self-monitoring technology uses conductive materials such as carbon fiber, carbon black, and nickel powder to reduce the resistivity of concrete. Usually, the amount of conductive material required to reach the conductive percolation threshold is relatively high (carbon fiber >0.5% volume content, carbon nanotubes >1% cement mass content), mainly focus on the strain under pressure, and the cost is expensive

Images