阅读说明：本技术 基于机械扫描成像声呐扫描桥墩基础冲刷的测点布设方法 (Measuring point layout method based on mechanical scanning imaging sonar scanning bridge pier foundation scouring ) 是由 沈圣 陈建腾 姜绍飞 曹峥 李明贤 于 2021-07-19 设计创作，主要内容包括：本发明提出基于机械扫描成像声呐扫描桥墩基础冲刷的测点布设方法,可通过布设多个用于安装声呐的测点对桥墩桩基础冲刷区地形进行完整检测,其特征在于：所述布设方法中,当桥墩桩基础为无承台单桩基础时,对无承台单桩基础以中心测点为基础绕桩周布设环向测点；当桥墩桩基础为有承台单排桩或有承台双排群桩基础时,在有承台的排桩基础处根据中心测点和承台位置关系对中心测点进行水平移动以布设相邻辅助测点；本发明可以实现对桥墩基础冲刷地形的完整检测,有利于进一步对桥墩基础冲刷地形进行三维重构。(The invention provides a measuring point arrangement method for scanning bridge pier foundation scouring based on mechanical scanning imaging sonar, which can carry out complete detection on the topography of a bridge pier foundation scouring area by arranging a plurality of measuring points for installing sonar, and is characterized in that: in the arrangement method, when the pile foundation of the pier is a single pile foundation without a bearing platform, annular measuring points are arranged on the single pile foundation without the bearing platform around the pile by taking a central measuring point as a foundation; when the pile foundation of the pier is a single-row pile foundation with a bearing platform or a double-row pile foundation with the bearing platform, horizontally moving the central measuring point at the pile foundation with the bearing platform according to the position relation of the central measuring point and the bearing platform so as to arrange adjacent auxiliary measuring points; the method can realize complete detection of the pier foundation erosion topography and is beneficial to further carrying out three-dimensional reconstruction on the pier foundation erosion topography.)

1. Based on the measuring point laying method that mechanical scanning imaging sonar scanned pier foundation erodees, the accessible lays a plurality of measuring points that are used for installing the sonar and carries out complete detection, its characterized in that to pier pile foundation erodees district's topography: in the arrangement method, when the pile foundation of the pier is a single pile foundation without a bearing platform, annular measuring points are arranged on the single pile foundation without the bearing platform around the pile by taking a central measuring point as a foundation; when the pile foundation of the pier is a single-row pile foundation with a bearing platform or a double-row pile group foundation with the bearing platform, the central measuring point is horizontally moved at the pile foundation with the bearing platform according to the position relation of the central measuring point and the bearing platform so as to arrange adjacent auxiliary measuring points.

2. The measuring point layout method based on mechanical scanning imaging sonar scanning pier foundation scouring according to claim 1, and is characterized in that: when the pile foundation of the pier is a single pile foundation without a bearing platform, if the movement of the central measuring point is not influenced by the shielding of the bearing platform, the adjacent auxiliary measuring points at two sides are arranged by horizontal transverse movement; the horizontal movement distance Δ x is taken as the beam coverage width between adjacent beams of about 20%:

Δ x ≈ (1-20%). ab formula one;

ab is the width of the square beam covered riverbed under the center measuring point of the sonar, and the calculation method is as follows:

wherein h is the detection distance between sonar and the foundation scoured riverbed.

3. The measuring point layout method based on mechanical scanning imaging sonar scanning pier foundation scouring according to claim 2, and is characterized in that: when the measurement points in the scour area are distributed aiming at the single-pile foundation without the bearing platform, if a group of measurement points in the same direction are taken as the foundation, n groups of measurement points are sequentially distributed by annularly rotating an angle alpha for complete detection of the foundation scour terrain with a pier as the center and a radius of R, the calculation formula of the beam coverage width AB of the group of measurement points comprising the center measurement point and the auxiliary measurement points at two sides is as follows:

AB 2 Δ x + AB 2.6AB formula three;

the calculation formula of the rotation angles of a group of measuring points in adjacent directions is as follows:

the formula for calculating the relationship between the number n of the annularly distributed measuring point groups and the rotation angle alpha is as follows:

in the formula, f (x) is a rounding function, and g (x) is a decimal function. f (2 pi/alpha) is an integer part of the number of the basic scour-laid measuring points, and g (2 pi/alpha) is a decimal part of the number of the basic scour-laid measuring points;

when the 2 pi/alpha can be divided completely, the number n of the annularly distributed measuring point groups is only required to be distributed with the integral number; when the 2 pi/alpha can not be divided completely, adding a measuring point on the basis of the number of the distributed integer points to completely scan the foundation to scour the terrain; after the number n of the measuring point groups distributed in the annular direction is determined, the final rotating angle alpha is₀The calculation formula of (2) is as follows:

4. the measuring point layout method based on mechanical scanning imaging sonar scanning pier foundation scouring according to claim 1, and is characterized in that: when the measuring point layout method is used for carrying out measuring point layout aiming at a scour area with a bearing platform single-row pile foundation, the following limitations are provided: if measuring points are annularly arranged at equal intervals d and equal angles alpha through the central measuring points, and the central measuring points are positioned below the bearing platform and cannot be arranged, extending the measuring points below the bearing platform to the edge of the bearing platform to arrange the central measuring points; if the auxiliary measuring points are horizontally and transversely arranged through the central measuring point, and the measuring points positioned at the edge of the bearing platform horizontally move towards one side of the bearing platform and are blocked by the bearing platform, adjacent auxiliary measuring points are arranged in a translation mode along the edge of the bearing platform, and the selected arrangement points need to prevent measuring point transmitting beams translated along the edge of the bearing platform from covering a river bed area or contacting with adjacent piles so as to avoid influencing the scouring to form an imaging result;

the above definition is expressed by formula

r≤A₁O_p1A formula seven;

wherein r is the radius of the bridge pier, A₁O_p1The shortest distance from the center of the adjacent pile 1 to the edge of the river bed area covered by sonar emission waves at the translated measuring point position is provided.

5. The measuring point layout method based on mechanical scanning imaging sonar scanning pier foundation scouring according to claim 1, and is characterized in that: when the measuring point layout method is used for carrying out measuring point layout aiming at a scouring area with a double-row pile foundation of a bearing platform, the following limitations are provided: if measuring points are uniformly distributed at equal intervals d and at equal angles alpha in a circumferential direction, and the central measuring points are located below the bearing platform and cannot be distributed, extending the measuring points below the bearing platform to the edge of the bearing platform to distribute the central measuring points; if the external delay of the central measuring point collides with pile bodies of the piles, the measuring points are distributed at the intersection points of the extension lines of the angle bisectors of the measuring points, the adjacent measuring points and the connecting line of the pile centers and the edge of the bearing platform so as to replace the original central measuring point to detect the washout terrain of the azimuth foundation.

6. The measuring point layout method based on mechanical scanning imaging sonar scanning pier foundation scouring according to claim 1, and is characterized in that: when the measuring point layout method is used for carrying out measuring point layout aiming at a scouring area with a double-row pile foundation of a bearing platform, the following requirements are met: if the horizontal translation of the measuring points positioned at the edge of the bearing platform to one side of the bearing platform is blocked by the bearing platform, arranging adjacent auxiliary measuring points in a translation mode along the edge of the bearing platform, and ensuring that measuring point transmitting beams translated along the edge of the bearing platform cover a riverbed area and are not in contact with a bridge pier; if the measuring point transmitting wave beam at the edge of the bearing platform is limited by the scanning space of the wave beam at the inner side of the pile group when scanning the terrain towards the inner side of the pile group, the adjacent auxiliary measuring point is not arranged at the position, but the measuring point transmitting wave beam at the position is ensured to cover the river bed area and not to contact with the pile body at the inner side of the pile group;

the above requirements can be formulated as:

r≤O_p4B₁and r is less than or equal to O_p5A₁A formula eight;

wherein r is the radius of the bridge pier, O_p4B₁Emitting a sonar wave beam to cover the shortest distance from the center point of the adjacent pile 4 to the edge of the riverbed area from the central measuring point position; o is_p5A₁The shortest distance from the central point of the adjacent pile 5 to the edge of the riverbed area covered by the sonar emission wave beam at the central measuring point position is obtained.

7. The measuring point layout method based on mechanical scanning imaging sonar scanning pier foundation scouring according to claim 1, and is characterized in that: when the measuring point layout method is used for carrying out measuring point layout aiming at a scouring area with a double-row pile foundation of a bearing platform, the following requirements are met: if the emitted wave beams are easy to contact with pile bodies inside the pile groups due to the limitation of the scanning space of the wave beams inside the pile groups when the wave beams emitted by the measuring points positioned at the edge of the bearing platform scan the terrain inside the pile groups, and the central measuring points are difficult to horizontally move to arrange adjacent auxiliary measuring points, a group of measuring points are constructed to detect the terrain inside the pile groups by utilizing the characteristic that the wave beam angle bisectors of the measuring points arranged on different pile foundations have parallel relation.

Technical Field

The invention relates to the technical field of detection of scoured terrain of an underwater pier foundation, in particular to a measuring point arrangement method based on mechanical scanning imaging sonar scanning pier foundation scour.

Background

In China, most bridge water damage damages are caused by that the buried depth of a pier foundation is reduced due to scouring, so that the capacity of a pile foundation bearing platform is remarkably reduced. The bridge water damage causes huge loss to lives and properties of people, and the bridge foundation scouring phenomenon is increasingly prominent along with the increasing of the number of bridges, so that the bridge foundation scouring is regularly detected, the bridge foundation scouring condition is mastered, and powerful information can be provided for structural state evaluation, scouring disaster prevention and the like of bridge engineering.

In recent years, with the progress of science and technology, detection instruments and detection techniques have been rapidly developed. The sonar has strong underwater environment adaptability, can still have good imaging effect in muddy water environment, and has high-efficiency detection efficiency, so that the sonar imaging technology is widely applied to pier foundation scouring detection. However, most of the existing detection methods for foundation erosion by using sonar imaging technology are to arrange measuring points in regions with serious bridge pier foundation erosion, lack complete detection for the bridge pier foundation erosion terrain, and are difficult to further restore the overall terrain and landform information of foundation erosion. In the existing research, sonar is adopted to carry out complete detection and three-dimensional reconstruction on the foundation erosion terrain, and the layout of sonar measuring points is a crucial factor.

Therefore, a measuring point layout method based on mechanical scanning imaging sonar scanning pier foundation scouring is needed.

Disclosure of Invention

The invention provides a measuring point layout method for scanning bridge pier foundation scour based on mechanical scanning imaging sonar, which can realize complete detection of bridge pier foundation scour terrain and is beneficial to further carrying out three-dimensional reconstruction on the bridge pier foundation scour terrain.

The invention adopts the following technical scheme.

The measuring point layout method based on the mechanical scanning imaging sonar scanning pier foundation scouring is characterized in that the topography of a pier pile foundation scouring area can be completely detected by arranging a plurality of measuring points for installing the sonar, and in the layout method, when the pier pile foundation is a single pile foundation without a bearing platform, annular measuring points are arranged on the single pile foundation without the bearing platform around the pile by taking a central measuring point as a foundation; when the pile foundation of the pier is a single-row pile foundation with a bearing platform or a double-row pile group foundation with the bearing platform, the central measuring point is horizontally moved at the pile foundation with the bearing platform according to the position relation of the central measuring point and the bearing platform so as to arrange adjacent auxiliary measuring points.

When the pile foundation of the pier is a single pile foundation without a bearing platform, if the movement of the central measuring point is not influenced by the shielding of the bearing platform, the adjacent auxiliary measuring points at two sides are arranged by horizontal transverse movement; the horizontal movement distance Δ x is taken as the beam coverage width between adjacent beams of about 20%:

Δ x ≈ (1-20%). ab formula one;

ab is the width of the square beam covered riverbed under the center measuring point of the sonar, and the calculation method is as follows:

wherein h is the detection distance between sonar and the foundation scoured riverbed.

When the measurement points in the scour area are distributed aiming at the single-pile foundation without the bearing platform, if a group of measurement points in the same direction are taken as the foundation, n groups of measurement points are sequentially distributed by annularly rotating an angle alpha for complete detection of the foundation scour terrain with a pier as the center and a radius of R, the calculation formula of the beam coverage width AB of the group of measurement points comprising the center measurement point and the auxiliary measurement points at two sides is as follows:

AB 2 Δ x + AB 2.6AB formula three;

the calculation formula of the rotation angles of a group of measuring points in adjacent directions is as follows:

the formula for calculating the relationship between the number n of the annularly distributed measuring point groups and the rotation angle alpha is as follows:

in the formula, f (x) is a rounding function, and g (x) is a decimal function. f (2 pi/alpha) is an integer part of the number of the basic scour-laid measuring points, and g (2 pi/alpha) is a decimal part of the number of the basic scour-laid measuring points;

when the 2 pi/alpha can be divided completely, the number n of the annularly distributed measuring point groups is only required to be distributed with the integral number; when the 2 pi/alpha can not be divided completely, adding a measuring point on the basis of the number of the distributed integer points to completely scan the foundation to scour the terrain; after the number n of the measuring point groups distributed in the annular direction is determined, the final rotating angle alpha is₀The calculation formula of (2) is as follows:

when the measuring point layout method is used for carrying out measuring point layout aiming at a scour area with a bearing platform single-row pile foundation, the following limitations are provided: if measuring points are annularly arranged at equal intervals d and equal angles alpha through the central measuring points, and the central measuring points are positioned below the bearing platform and cannot be arranged, extending the measuring points below the bearing platform to the edge of the bearing platform to arrange the central measuring points; if the auxiliary measuring points are horizontally and transversely arranged through the central measuring point, and the measuring points positioned at the edge of the bearing platform horizontally move towards one side of the bearing platform and are blocked by the bearing platform, adjacent auxiliary measuring points are arranged in a translation mode along the edge of the bearing platform, and the selected arrangement points need to prevent measuring point transmitting beams translated along the edge of the bearing platform from covering a river bed area or contacting with adjacent piles so as to avoid influencing the scouring to form an imaging result;

the above definition is expressed by formula

r≤A₁O_p1A formula seven;

wherein r is the radius of the bridge pier, A₁O_p1The shortest distance from the center of the adjacent pile 1 to the edge of the river bed area covered by sonar emission waves at the translated measuring point position is provided.

When the measuring point layout method is used for carrying out measuring point layout aiming at a scouring area with a double-row pile foundation of a bearing platform, the following limitations are provided: if measuring points are uniformly distributed at equal intervals d and at equal angles alpha in a circumferential direction, and the central measuring points are located below the bearing platform and cannot be distributed, extending the measuring points below the bearing platform to the edge of the bearing platform to distribute the central measuring points; if the external delay of the central measuring point collides with pile bodies of the piles, the measuring points are distributed at the intersection points of the extension lines of the angle bisectors of the measuring points, the adjacent measuring points and the connecting line of the pile centers and the edge of the bearing platform so as to replace the original central measuring point to detect the washout terrain of the azimuth foundation.

When the measuring point layout method is used for carrying out measuring point layout aiming at a scouring area with a double-row pile foundation of a bearing platform, the following requirements are met: if the horizontal translation of the measuring points positioned at the edge of the bearing platform to one side of the bearing platform is blocked by the bearing platform, arranging adjacent auxiliary measuring points in a translation mode along the edge of the bearing platform, and ensuring that measuring point transmitting beams translated along the edge of the bearing platform cover a riverbed area and are not in contact with a bridge pier; if the measuring point transmitting wave beam at the edge of the bearing platform is limited by the scanning space of the wave beam at the inner side of the pile group when scanning the terrain towards the inner side of the pile group, the adjacent auxiliary measuring point is not arranged at the position, but the measuring point transmitting wave beam at the position is ensured to cover the river bed area and not to contact with the pile body at the inner side of the pile group; the above requirements can be formulated as:

r≤O_p4B₁and r is less than or equal to O_p5A₁A formula eight;

wherein r is the radius of the bridge pier, O_p4B₁Emitting a sonar wave beam to cover the shortest distance from the center point of the adjacent pile 4 to the edge of the riverbed area from the central measuring point position; o is_p5A₁The shortest distance from the central point of the adjacent pile 5 to the edge of the riverbed area covered by the sonar emission wave beam at the central measuring point position is obtained.

When the measuring point layout method is used for carrying out measuring point layout aiming at a scouring area with a double-row pile foundation of a bearing platform, the following requirements are met: if the emitted wave beams are easy to contact with pile bodies inside the pile groups due to the limitation of the scanning space of the wave beams inside the pile groups when the wave beams emitted by the measuring points positioned at the edge of the bearing platform scan the terrain inside the pile groups, and the central measuring points are difficult to horizontally move to arrange adjacent auxiliary measuring points, a group of measuring points are constructed to detect the terrain inside the pile groups by utilizing the characteristic that the wave beam angle bisectors of the measuring points arranged on different pile foundations have parallel relation.

According to the scheme, the complete detection of the pier foundation scour terrain can be realized, and the three-dimensional reconstruction of the pier foundation scour terrain is facilitated.

Drawings

The invention is described in further detail below with reference to the following figures and detailed description:

FIG. 1 is a schematic diagram of arrangement of a center measuring point and adjacent auxiliary measuring points of a single pile without a bearing platform;

FIG. 2 is a schematic diagram of circumferential measuring point arrangement based on a single pile group of measuring points without a bearing platform;

FIG. 3 is a schematic diagram of the arrangement of single-row pile measuring points with a bearing platform;

FIG. 4 is a schematic diagram of the arrangement of the measuring points of the double rows of piles with the bearing platform.

FIG. 5 is a schematic diagram of detecting the terrain inside the pile group by constructing a group of measuring points by using measuring points laid by different pile foundations.

Detailed Description

As shown in the figure, the measuring point arrangement method based on the mechanical scanning imaging sonar scanning pier foundation scouring can completely detect the topography of a pier pile foundation scouring area by arranging a plurality of measuring points for installing the sonar, and in the arrangement method, when the pier pile foundation is a single pile foundation without a bearing platform, annular measuring points are arranged on the single pile foundation without the bearing platform around the pile by taking a central measuring point as a foundation; when the pile foundation of the pier is a single-row pile foundation with a bearing platform or a double-row pile group foundation with the bearing platform, the central measuring point is horizontally moved at the pile foundation with the bearing platform according to the position relation of the central measuring point and the bearing platform so as to arrange adjacent auxiliary measuring points.

When the pile foundation of the pier is a single pile foundation without a bearing platform, if the movement of the central measuring point is not influenced by the shielding of the bearing platform, the adjacent auxiliary measuring points at two sides are arranged by horizontal transverse movement; the horizontal movement distance Δ x is taken as the beam coverage width between adjacent beams of about 20%:

Δ x ≈ (1-20%). ab formula one;

ab is the width of the square beam covered riverbed under the center measuring point of the sonar, and the calculation method is as follows:

wherein h is the detection distance between sonar and the foundation scoured riverbed.

When the measurement points in the scour area are distributed aiming at the single-pile foundation without the bearing platform, if a group of measurement points in the same direction are taken as the foundation, n groups of measurement points are sequentially distributed by annularly rotating an angle alpha for complete detection of the foundation scour terrain with a pier as the center and a radius of R, the calculation formula of the beam coverage width AB of the group of measurement points comprising the center measurement point and the auxiliary measurement points at two sides is as follows:

AB 2 Δ x + AB 2.6AB formula three;

the calculation formula of the rotation angles of a group of measuring points in adjacent directions is as follows:

the formula for calculating the relationship between the number n of the annularly distributed measuring point groups and the rotation angle alpha is as follows:

in the formula, f (x) is a rounding function, and g (x) is a decimal function. f (2 pi/alpha) is an integer part of the number of the basic scour-laid measuring points, and g (2 pi/alpha) is a decimal part of the number of the basic scour-laid measuring points;

when the 2 pi/alpha can be divided completely, the number n of the annularly distributed measuring point groups is only required to be distributed with the integral number; when the 2 pi/alpha can not be divided completely, adding a measuring point on the basis of the number of the distributed integer points to completely scan the foundation to scour the terrain; after the number n of the measuring point groups distributed in the annular direction is determined, the final rotating angle alpha is₀The calculation formula of (2) is as follows:

when the measuring point layout method is used for carrying out measuring point layout aiming at a scour area with a bearing platform single-row pile foundation, the following limitations are provided: if measuring points are annularly arranged at equal intervals d and equal angles alpha through the central measuring points, and the central measuring points are positioned below the bearing platform and cannot be arranged, extending the measuring points below the bearing platform to the edge of the bearing platform to arrange the central measuring points; if the auxiliary measuring points are horizontally and transversely arranged through the central measuring point, and the measuring points positioned at the edge of the bearing platform horizontally move towards one side of the bearing platform and are blocked by the bearing platform, adjacent auxiliary measuring points are arranged in a translation mode along the edge of the bearing platform, and the selected arrangement points need to prevent measuring point transmitting beams translated along the edge of the bearing platform from covering a river bed area or contacting with adjacent piles so as to avoid influencing the scouring to form an imaging result;

the above definition is expressed by formula

r≤A₁O_p1A formula seven;

wherein r is the radius of the bridge pier, A₁O_p1The shortest distance from the center of the adjacent pile 1 to the edge of the river bed area covered by sonar emission waves at the translated measuring point position is provided.

When the measuring point layout method is used for carrying out measuring point layout aiming at a scouring area with a double-row pile foundation of a bearing platform, the following limitations are provided: if measuring points are uniformly distributed at equal intervals d and at equal angles alpha in a circumferential direction, and the central measuring points are located below the bearing platform and cannot be distributed, extending the measuring points below the bearing platform to the edge of the bearing platform to distribute the central measuring points; if the external delay of the central measuring point collides with pile bodies of the piles, the measuring points are distributed at the intersection points of the extension lines of the angle bisectors of the measuring points, the adjacent measuring points and the connecting line of the pile centers and the edge of the bearing platform so as to replace the original central measuring point to detect the washout terrain of the azimuth foundation.

As shown in (a) of figure 4,by measuring the point where the extension will collide with the pile body, and thus, byAndintersection point position of extension line of angular bisector of included angle and edge of bearing platformArranging measuring points to obtain the measuring points Replace the original central measuring point

When the measuring point layout method is used for carrying out measuring point layout aiming at a scouring area with a double-row pile foundation of a bearing platform, the following requirements are met: if the horizontal translation of the measuring points at the edge of the bearing platform towards one side of the bearing platform is blocked by the bearing platform, the adjacent auxiliary measuring points are arranged in a translation mode along the edge of the bearing platform, such as the measuring points in the graph 4(a)By moving along the edge of the platform to arrange adjacent measuring pointsThe condition is the same as that of the row pile, and a measuring point after translation along the edge of the bearing platform needs to be ensuredThe emitted wave beams cover the river bed area and are not in contact with the bridge piers.

If the test point is located at the edge of the platform, as shown in FIG. 4 (b)When the emitted wave beams scan the inner side topography of the grouped piles, the emitted wave beams are limited by the scanning space of the inner side wave beams of the grouped piles, the emitted wave beams are easy to contact with the inner side piles 4 and the inner side piles 5 of the grouped piles, and the auxiliary measuring points are difficult to move and arrange along the edge of the bearing platform, so that the adjacent auxiliary measuring points are not arranged at the position, but the measuring points at the position are ensuredThe emitted wave beams cover the river bed area and are not contacted with pile bodies (piles 4 and 5) on the inner sides of the grouped piles;

the above requirements can be formulated as:

r≤O_p4B₁and r is less than or equal to O_p5A₁A formula eight;

wherein r is the radius of the bridge pier, O_p4B₁Emitting a sonar wave beam to cover the shortest distance from the center point of the adjacent pile 4 to the edge of the riverbed area from the central measuring point position; o is_p5A₁The shortest distance from the central point of the adjacent pile 5 to the edge of the riverbed area covered by the sonar emission wave beam at the central measuring point position is obtained.

When the measuring point layout method is used for carrying out measuring point layout aiming at a scouring area with a double-row pile foundation of a bearing platform, the following requirements are met: if the emitted wave beams are easy to contact with pile bodies inside the pile groups due to the limitation of the scanning space of the wave beams inside the pile groups when the wave beams emitted by the measuring points positioned at the edge of the bearing platform scan the terrain inside the pile groups, and the central measuring points are difficult to horizontally move to arrange adjacent auxiliary measuring points, a group of measuring points are constructed to detect the terrain inside the pile groups by utilizing the characteristic that the wave beam angle bisectors of the measuring points arranged on different pile foundations have parallel relation. As shown in FIG. 5, the pass measurement pointThe emitted beam angle bisectors have parallel relation to form a group of measuring points, and the measuring points are similarForm a set of measuring points And forming a group of measuring points to detect the foundation erosion topography of the area inside the pile group.

The above description is only a preferred embodiment of the present invention, and the embodiments are based on different implementation manners of the overall concept, and the protection scope of the present invention is not limited thereto. The function and the using method of the invention are only explained and not limited to the invention, and the person skilled in the art can make various changes or substitutions within the spirit scope of the invention and also fall into the protection scope of the invention.