Method of measuring length and mass of brad and pile
A technology of soil nailing and quality, which is applied in the direction of measuring devices, instruments, and optical devices, which can solve the problems of high price, poor applicability and reliability, and high cost, and achieve the effects of anti-corrosion, anti-electromagnetic interference, and ease of use
Active Publication Date: 2007-12-05
THE HONG KONG POLYTECHNIC UNIV
View PDF3 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
[0004] Existing techniques for measuring the length and quality of soil nails and piles have many limitations, such as: (1) non-destructive techniques based on stress wave propagation theory are difficult to measure the length of piles / soil nails that are long and / or have connection points, This is because for longer piles / soil nails, the reflected wave will be too weak and will mix with the reflected wave from the connection point and the surrounding soil, so the applicability and reliability of this technique are poor; (2) Ultrasonic scanning method The cost is too high, and at least two (usually four) plastic sleeves or steel sleeves with a diameter of 40 mm to 100 mm need to be pre-installed on a pile; There are two plastic casings installed by nails, so this technology is not suitable for soil nails at all, and the cost is too high for piles; (3) The concrete coring method is more reliable for concrete piles, but expensive
In addition, this core drilling method is not suitable for soil nails with a diameter of only 100 mm
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0025] The general measurement steps of the method of the present invention are:
[0026] The first step is to sense the change of the length of the fiber optic sensor embedded in the soil nail or pile under the axial force load based on the principles of mechanics and optics, and convert it into a physical quantity that can calculate the strain of the fiber optic sensor ;
[0027] The second step is to calculate the strain and length of the optical fiber sensor according to the obtained physical quantity that can calculate the strain of the optical fiber sensor;
[0028] In the third step, according to the measured strain of the soil nail or pile, the axial strain distribution along the soil nail or pile can be known, and the mass of the measured soil nail or pile can be calculated.
[0029] Among them, the first step and the second step are realized in two ways, and the optical principles of their composition and use are as follows:
[0030] (a) By setting multiple reflect...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The method of measuring length and mass of brad and pile includes the following steps: setting sensors on the sensing optical fiber; embedding the fiber axially inside the pile or brad, with the fiber being in the same arranged length as the pile or brad; connecting the fiber with to the light source and the reflected wave receiver; connecting the reflected wave receiver connected successively to the data collecting recorder and the data treating circuit; applying axial load to the exposed head of the pile or brad with some loading unit; obtaining the physical quantity for calculating the strain of the sensor under the action of the axial load with the reflected wave receiver; and calculating the strain distribution, length and mass of the pile or brad with the physical quantity in the data treating circuit. The present invention has wide measurement application, high reliability, low cost, high electromagnetic interference resistance and other advantages.
Description
technical field [0001] The invention relates to the field of civil engineering, in particular to a method for measuring the length and quality of soil nails and piles by using an optical fiber measuring device. Background technique [0002] Pile and soil nails are important structures in civil engineering. Piles are used to support the superstructure of buildings, bridges etc. and are of different types: eg H-shaped steel piles and bored concrete piles with a diameter of 1 to 3 meters. Soil nails are used to stabilize slopes with low standard soils. The soil nails are constructed by placing a steel bar or other slender rod of material in the middle of a pre-drilled hole having a diameter of 100mm in the slope of the soil and grouting the full length of the hole. A soil nail is like a slender pile with a diameter of about 100mm and a length of 5m to 30m. [0003] Piles and soil nails are generally buried in soil or rock, so it is difficult to check their actual length and ...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): G01B11/16
Inventor 殷建华靳伟
Owner THE HONG KONG POLYTECHNIC UNIV