Cast-in-place X-type concrete pile body strain monitoring method based on FBG (Fiber Bragg Grating) sensor

Abstract

The invention discloses a cast-in-place X-type concrete pile body strain monitoring method based on an FBG (Fiber Bragg Grating) sensor. The cast-in-place X-type concrete pile body strain monitoring method comprises the following steps: flattening the surface of an X-type concrete pile body; axially paving four optical fibers at convex and concave positions on the surface of the processed pile body; adhering the FBG sensor serially connected with the optical fibers on the surface of the pile body; coating epoxy resin; accessing to a fiber bragg grating interrogator and measuring a strain value of the pile body. According to the monitoring method provided by the invention, the survival rate of the optical fiber sensor is improved; the electromagnetic interference can be avoided; the cast-in-place X-type concrete pile body strain monitoring method has the advantages of good waterproof property, high testing precision, good stability and the like.

Description

technical field [0001] The invention relates to a test method of a foundation structure, in particular to a strain monitoring method of an in-situ X-shaped concrete pile body based on an FBG sensor. Background technique [0002] The cast-in-place X-shaped concrete pile uses a letter X-shaped section instead of the traditional circular section. Compared with the traditional round pile with the same cross-sectional area, the cross-sectional circumference of the cast-in-place X-shaped concrete pile is significantly increased, and the unit material The specific surface area is also significantly increased, thereby achieving the purpose of saving pile body materials and improving the bearing capacity of material per unit volume. Therefore, the single pile bearing capacity can be greatly improved without increasing the amount of concrete poured, thereby improving the cost performance. It can be widely used in foundation engineering in the fields of expressway, high-speed railway,...

AI Technical Summary

Problems solved by technology

[0003] Currently, strain gauges are mainly used to monitor the strain of cast-in-situ X-shaped concrete piles. However, due to the complicated installation and laying of strain gauges and their easy damage, the continuous strain data of piles cannot be collected, and there are too many lead-out lines of strain gauges. , easy to cause knotting during operation, and the lead wire is easy to break, the survival rate is not high enough

Images