阅读说明：本技术 一种基于形状传感器的测斜装置及测斜方法 (Inclination measuring device and inclination measuring method based on shape sensor ) 是由 任亮 尤润州 于 2019-10-31 设计创作，主要内容包括：本发明公开了一种基于形状传感器的测斜装置及测斜方法,测斜装置包括测斜管、形状传感器和滑动夹具。所述滑动夹具通过机械连接固定在形状传感器上,所述形状传感器通过滑动夹具滑入并固定在测斜管内部,所述形状传感器包括薄壁钢管和应变传感器,所述薄壁钢管外表面沿环向每间隔120°设有圆弧凹槽,所述应变传感器每隔一定间距胶结在薄壁钢管外表面的圆弧凹槽内。测斜方法通过应变传感器获得各测点应变信息,结合形状传感算法实现测斜管水平位移重构。本发明将形状传感器和测斜管结合,具有安装方便、测量精度高、环境适应性强、造价低廉的优点。(The invention discloses an inclination measuring device and an inclination measuring method based on a shape sensor. The sliding clamp is fixed on the shape sensor through mechanical connection, the shape sensor slides into the inclinometer through the sliding clamp and is fixed in the inclinometer, the shape sensor comprises a thin-wall steel pipe and strain sensors, arc grooves are formed in the outer surface of the thin-wall steel pipe at intervals of 120 degrees in the circumferential direction, and the strain sensors are cemented in the arc grooves in the outer surface of the thin-wall steel pipe at intervals. The inclination measuring method obtains strain information of each measuring point through a strain sensor, and combines a shape sensing algorithm to realize horizontal displacement reconstruction of the inclination measuring pipe. The invention combines the shape sensor and the inclinometer, and has the advantages of convenient installation, high measurement precision, strong environmental adaptability and low cost.)

1. The utility model provides an inclinometry device based on shape sensor which characterized in that, includes inclinometer pipe, shape sensor and slide fixture, slide fixture cup joints on the shape sensor outer wall, shape sensor slides in and fixes in the inclinometer inside through slide fixture.

2. The inclination measuring device based on the shape sensor according to claim 1, wherein the shape sensor comprises a thin-wall steel pipe and strain sensors, arc grooves are arranged on the outer surface of the thin-wall steel pipe at intervals of 120 degrees along the circumferential direction, and the strain sensors are cemented in the arc grooves on the outer surface of the thin-wall steel pipe at intervals.

3. The inclination measuring device based on the shape sensor is characterized in that the sliding clamp comprises a member a, a member b and a locking screw, one end of the member a and one end of the member b are rotatably connected through a pin, the other end of the member a and the other end of the member b are fixedly connected through the matching of a screw and a nut, circular columns are distributed on the outer walls of the member a and the member b, and the circular columns are connected with the locking screw through a twisted wire; the inner diameter of the sliding clamp is the same as the outer diameter of the thin-wall steel pipe.

4. The device of claim 1, wherein a guide groove is formed on the inner wall of the inclinometer casing, and a round ball at the top of the locking screw is slidably connected with the guide groove.

5. A method for measuring inclination based on a shape sensor is characterized by comprising the following specific steps:

step 1: dividing the shape sensor into n units, wherein each unit is provided with a curvature measuring point, and each curvature measuring point is provided with a strain sensor at intervals of a certain angle along the circumferential direction;

step 2: expressing the curvature of each measuring point in a curvature vector form;

and step 3: suppose in the ith segment [ x_i,x_i+1]If the curvature in the cell is uniformly changed, the curvature is expressed as a linear function of x;

and 4, step 4: when the ith segment unit node coordinate x_iAnd an initial rotation angle theta_iWhen known, in the interval [ x_i,x]The curvature function is integrated for one time to obtain an interval [ x ]_i,x]The rotation angle value of any point inside;

and 5: when the ith segment unit node coordinate x_iInitial rotation angle theta_iAnd initial displacement omega_iWhen known, in the interval [ x_i,x]The upper integral of the rotation angle function is carried out to obtain an interval [ x ]_i,x]Any point inside has a deflection value.

6. The method of claim 5, wherein each strain sensor in step 1 is related to the bending curvature by

ε_ij＝k_ir sin(α_b-α_ij)

Wherein epsilon_ijMeasured strain value of jth strain sensor at a measuring point i, j belongs to [1,3 ]](ii) a i is the curvature measuring point number, i belongs to [1, n ]]；k_iThe bending curvature at the measuring point i is shown; r is the distance from the center of the thin-wall steel pipe to the center of the strain sensor; alpha is alpha_ijThe included angle between the jth sensor at the measuring point i and the z axis is shown; alpha is alpha_bIs the included angle between the neutral axis and the z axis.

7. The method of claim 6, wherein the curvature vector form of step 2 is expressed as:

the curvature value of each measuring point is

8. The method of claim 7, wherein the first order function of the curvature represented as x in step 3 is:

9. the method of claim 8, wherein the shape sensor-based inclinometer,

interval [ x ] in step 4_i,x]The rotation angle value of any point inside is as follows:

10. the method of claim 9, wherein the shape sensor-based inclinometer,

interval [ x ] in step 5_i,x]The flexibility value of any point inside is as follows:

Technical Field

The invention belongs to the technical field of inclination measurement, and particularly relates to an inclination measurement device and an inclination measurement method based on a shape sensor.

Background

In recent years, with the continuous development of urban construction such as high-rise buildings, subways and the like, the depth and scale of excavation of a foundation pit are continuously enlarged, and engineering accidents (such as foundation pit collapse, peripheral soil subsidence and support system breakage) caused by the excavation are also continuously increased. In order to master the stability of the foundation pit in real time and ensure the safety of personnel and equipment during construction, the importance of foundation pit monitoring in construction is increasingly prominent. The horizontal displacement of the deep layer of the foundation pit is used as the most direct embodiment of the soil state of the foundation pit, is one of important monitoring items in the construction process, and the monitoring result is important for evaluating the stability and the construction safety of the foundation pit.

At present, the horizontal displacement of the deep layer of the foundation pit is mainly measured by combining an inclinometer and an inclinometer. After the inclinometer pipe is buried, a probe of the inclinometer is placed into the pipe along an internal groove of the inclinometer pipe, and horizontal displacement values are read every 0.5m or 1m, so that the measurement method has the following limitations and disadvantages:

1. the measuring efficiency is low, the labor cost is high, the acquisition time is long, and full-automatic measurement cannot be realized.

2. The measurement accuracy is low, and data acquisition is influenced by human factors greatly, and for point measurement, the data is incomplete, is difficult to accurately reflect the global displacement change.

3. The measurement work is greatly influenced by environmental factors, and cannot be monitored under extreme environmental conditions such as rainstorm and the like.

Disclosure of Invention

Aiming at the defects and shortcomings in the prior art, the invention provides the inclination measuring device and the inclination measuring method based on the shape sensor, and the inclination measuring device and the inclination measuring method have the advantages of convenience in installation, high measuring precision, strong environmental adaptability and low manufacturing cost.

In order to achieve the purpose, the technical scheme of the application is as follows: the utility model provides an inclinometry device based on shape sensor, includes inclinometer pipe, shape sensor and slide fixture, slide fixture cup joints on the shape sensor outer wall, shape sensor slides in and fixes in the inclinometer intraduct through slide fixture.

Furthermore, the shape sensor comprises a thin-wall steel pipe and strain sensors, arc grooves are arranged on the outer surface of the thin-wall steel pipe at intervals of 120 degrees along the circumferential direction, and the strain sensors are cemented in the arc grooves on the outer surface of the thin-wall steel pipe at intervals.

Further, the sliding clamp comprises a member a, a member b and a locking screw, one end of the member a and one end of the member b are rotatably connected through a pin, the other end of the member a and the other end of the member b are fixedly connected through matching of the screw and a nut, circular columns are distributed on the outer walls of the member a and the member b, and the circular columns are connected with the locking screw through a twisted wire; the inner diameter of the sliding clamp is the same as the outer diameter of the thin-wall steel pipe.

Furthermore, a guide groove is formed in the inner wall of the inclinometer tube, and a round ball at the top of the locking screw is connected with the guide groove in a sliding mode.

The application also provides an inclination measurement method based on the shape sensor, which comprises the following specific steps:

step 1: dividing the shape sensor into n units, arranging a curvature measuring point on each unit, and arranging 1 strain sensor at each interval of 120 degrees at each curvature measuring point along the annular direction;

step 2: expressing the curvature of each measuring point in a curvature vector form;

and step 3: suppose in the ith segment [ x_i,x_i+1]If the curvature in the cell is uniformly changed, the curvature is expressed as a linear function of x;

and 4, step 4: when the ith segment unit node coordinate x_iAnd an initial rotation angle theta_iWhen known, in the interval [ x_i,x]The curvature function is integrated for one time to obtain an interval [ x ]_i,x]The rotation angle value of any point inside;

and 5: when the ith segment unit node coordinate x_iInitial rotation angle theta_iAnd initial displacement omega_iWhen known, in the interval [ x_i,x]The upper integral of the rotation angle function is carried out to obtain an interval [ x ]_i,x]Any point inside has a deflection value.

Further, each strain sensor in step 1 has a relation with the bending curvature of

ε_ij＝k_ir sin(α_b-α_ij)

Wherein epsilon_ijMeasured strain value of jth strain sensor at a measuring point i, j belongs to [1,3 ]](ii) a i is the curvature measuring point number, i belongs to [1, n ]]；k_iThe bending curvature at the measuring point i is shown; r is the distance from the center of the thin-wall steel pipe to the center of the strain sensor; alpha is alpha_ijThe included angle between the jth sensor at the measuring point i and the z axis is shown; alpha is alpha_bIs the included angle between the neutral axis and the z axis.

Further, the curvature vector form of step 2 is expressed as:

the curvature value of each measuring point is

Further, the curvature in step 3 is expressed as a linear function of x as:

further, the interval [ x ] in step 4_i,x]The rotation angle value of any point inside is as follows:

further, the interval [ x ] in step 5_i,x]The flexibility value of any point inside is as follows:

due to the adoption of the technical scheme, the invention can obtain the following technical effects:

1. this application combines together shape sensor and deviational survey pipe, can realize the long-range long-term real-time supervision of deviational survey pipe horizontal displacement, and does not receive the influence of environmental climate, has the advantage that measurement accuracy is high, the noise immunity can be strong.

2. This application adopts along the hoop every interval 120 to lay 1 strain sensor's the mode of laying, effectively eliminates temperature and crooked direction to camber measuring's influence, need not extra temperature compensation, effectively improves the computational accuracy.

3. The later stage of this application shape sensor is buried, has greatly improved the survival rate of sensor for this deviational survey pipe not only is applicable to deep basal pit displacement monitoring, can be used for the displacement monitoring of ground structures such as pile body, dam, side slope moreover, has easy operation, construction convenience, the advantage that sensing unit cost is low.

4. By adopting the method to calculate the horizontal displacement of the inclinometer, the reconstruction of the global displacement field of the inclinometer can be realized only by giving boundary conditions without material and load information.

Drawings

FIG. 1 is a schematic structural diagram of a shape sensor-based inclinometer according to the present application;

FIG. 2 is a cross-sectional view of the inclinometer of the present application;

FIG. 3 is a cross-sectional view of the shape sensor of the present application;

FIG. 4 is a schematic view of the slide clamp of the present application;

in the figure: 101-inclinometer pipe, 102-shape sensor, 103-sliding clamp, 201-thin-wall steel pipe, 202-fiber grating strain sensor, 301-component a, 302-component b, 303-locking screw and 4-neutral axis.

Detailed Description

The embodiments of the present invention are implemented on the premise of the technical solution of the present invention, and detailed embodiments and specific operation procedures are given, but the scope of the present invention is not limited to the following embodiments.