CN103114670A - Piezoelectric ceramic rod structure single-layer spherical reticulated shell and rod internal force monitoring device - Google Patents

Abstract

A piezoelectric ceramic rod structure single-layer spherical reticulated shell and a device for monitoring the internal force of the rod. The spherical reticulated shell includes multiple upper chords, multiple lower chords, multiple diagonal webs, multiple ceramic rod connectors, multiple bolt ball joints, several sliding hinge supports and several fixed hinge supports. The monitoring device includes wireless sensors, data receiving base stations, data analyzers and wires. The single-layer and double-layer spherical reticulated shell with piezoelectric ceramic rod structure provided by the invention has the advantages of good shock resistance, convenient construction and the like. The internal force monitoring device of the rod has high accuracy of results; it is not affected by environmental factors and has strong anti-aging ability, and can be used for long-term monitoring; it is not restricted by the position of the rod, and does not need to arrange super long data lines, which is convenient for carrying out experiments; high safety, etc. advantage.

Description

Piezoelectric ceramic rod structure single-layer spherical reticulated shell and rod internal force monitoring device

technical field

The invention belongs to the technical field of building structures, and in particular relates to a piezoelectric ceramic rod structure single-layer spherical reticulated shell and a device for monitoring the internal force of the rod.

Background technique

With the development of large-span space structures, reticulated shell structures have been widely used, such as airport terminals, convention centers, toll stations, theaters and other buildings, all of which have application examples of reticulated shell structures. The grid structure has reasonable force, high rigidity, and light weight, which can give full play to the tensile and compressive properties of the material, reduce the adverse effects of bending moment and shear force on the material, and the shape is changeable, and the grid size can be adjusted according to the requirements of the building. , The appearance of the building is transparent and beautiful, which can effectively use natural lighting and reduce building energy consumption. However, the span of the reticulated shell structure is controlled by local stability and overall stability, so the application range is also limited to a certain extent. In addition, reticulated shell structures are currently mainly made of steel, and there are no research reports on the application of other materials to reticulated shell structures.

Piezoelectric ceramics are a new type of material discovered in 1946 by researchers at the Massachusetts Institute of Technology's Insulation Laboratory. Under the action of external mechanical force, the positive and negative charge centers inside the material will undergo relative displacement to cause polarization, resulting in bound charges with opposite signs on the surface of the material at both ends. However, the existing piezoelectric ceramic materials are mainly used in buzzers, loudspeakers, pickups, transformers, igniters and other fields, and there are no research reports on their application in the field of construction engineering, especially in reticulated shell structures.

In addition, the internal force monitoring of the member is an important content in the study of the failure mechanism of the reticulated shell structure and the analysis of the collapse process. The existing monitoring methods mainly include: attaching strain gauges or strain sensors to calculate internal force and using vibration sensors to collect vibration signals of rods to calculate internal force. However, the strain gauge or strain sensor has a short service life, and is affected by factors such as temperature and zero drift during use, so the accuracy of long-term monitoring of the internal force of the rod is poor; The vibration signal of the rod needs to be filtered, and the results will inevitably be distorted during the filtering process. Therefore, the research and development of the rod internal force measurement device for the reticulated shell structure and the improvement of the accuracy of the measurement results will promote the further development of the theoretical research and design application of the reticulated shell structure.

In short, how to apply the new material of piezoelectric ceramics to the shell structure, make it a stressed member of the space structure through reasonable node design, and use the characteristics of piezoelectric ceramics to calculate the rod according to the voltage value of the rod It has become an important issue to promote the application of piezoelectric ceramics and promote the development of shell structures in order to monitor the force of rods dynamically in real time and verify the theoretical analysis results.

Contents of the invention

In order to solve the above problems, the object of the present invention is to provide a piezoelectric ceramic rod structure single-layer spherical reticulated shell with good anti-seismic performance and convenient construction.

Another object of the present invention is to provide a device for monitoring the internal force of the rod on the single-layer spherical reticulated shell with the above-mentioned piezoelectric ceramic rod structure with accurate measurement results and high safety.

In order to achieve the above purpose, the piezoelectric ceramic rod structure single-layer spherical reticulated shell provided by the present invention includes a plurality of upper chords, a plurality of lower chords, a plurality of oblique webs, a plurality of ceramic rod connectors, a plurality of bolt ball nodes, Several sliding hinge supports and several fixed hinge supports; the upper chord, lower chord and diagonal rods are all piezoelectric ceramic rods, and a ceramic Rod connectors; multiple upper chord rods, multiple lower chord rods and multiple diagonal web rods with ceramic rod connectors are connected into a single-layer spherical reticulated shell body of traditional shape by using multiple bolted ball joints; the ceramic rods The connecting piece includes multiple embedded bolts, end plates, cone heads and multiple nuts; wherein multiple embedded bolts are installed on the outer edge of the upper chord, lower chord or diagonal web; the end plate is formed with multiple The round hole corresponding to the position of the embedded bolt is fixed on the outer end surface of the upper chord, lower chord or diagonal rod with nuts; the cone head is a hollow circular platform structure, and a round hole is formed in the middle of the upper bottom surface, and the lower bottom surface is open. shape, and the edge of the lower bottom surface is connected to the outer end edge of the end plate; each bolt ball node includes multiple high-strength bolts, multiple sealing plates, multiple sleeves, multiple pins and a steel ball; the high-strength bolts on the The screw rod runs through the circular hole provided on the cone head, and the bolt head is located inside the cone head, and at the same time, a blind hole is formed radially on the outer peripheral surface of the middle part of the screw rod; the sealing plate is installed outside the upper bottom surface of the cone head, and A screw hole is formed in the center; the sleeve is set on the high-strength bolt on the screw outside the sealing plate, and a pin hole is formed on the circumferential surface of the sleeve; the front end of the pin is inserted through the pin hole on the sleeve In the blind holes on the high-strength bolts; there are multiple round holes formed on the steel balls, which are used to insert the front ends of the screw rods on multiple high-strength bolts; On the bolt ball joint, the lower end is fixed on the top of the structural column; the upper ends of several sliding hinge supports are installed on the remaining upper chord bolt ball joints of the reticulated shell body at a distance, and the lower end is set on the top of the structural column in a movable manner.

The upper chord, the lower chord and the diagonal rod are all hollow piezoelectric ceramic round rods.

The number of embedded bolts and nuts on each bolt ball node is 5-7.

The outer surfaces of the embedded bolts and the end plates are coated with an insulating coating.

The internal force monitoring device of the upper rod of the piezoelectric ceramic rod structure single-layer spherical reticulated shell provided by the invention includes a wireless sensor, a data receiving base station, a data analyzer and a wire; wherein each upper chord, lower chord and diagonal rod are respectively installed There is a wireless sensor, and two wires are preset on each top chord, bottom chord and diagonal rod, one end of each wire is connected to one end of the top chord, bottom chord and diagonal rod, and the other end is connected to the wireless sensor. connected; the wireless sensor is wirelessly connected to the data receiving base station set on the ground; and the data receiving base station and the data analyzer are connected through the data line.

The piezoelectric ceramic rod structure single-layer spherical reticulated shell provided by the present invention has the following advantages: 1) good shock resistance: after calculation by the general-purpose finite element analysis software ANSYS, it is found that the single root of the piezoelectric ceramic rod structure single-layer spherical reticulated shell The stress of the components and the overall static and dynamic deformation of the structure can meet the requirements of use. 2) Easy construction: The density of piezoelectric ceramic rods is lower than that of steel, and the structural installation can be completed by using existing construction methods and equipment.

The internal force monitoring device of the rod on the piezoelectric ceramic rod structure single-layer spherical reticulated shell provided by the present invention has the following advantages: 1) According to the mutual conduction formula between pressure and voltage, the force on the rod can be accurately measured, and the accuracy of the result is high. 2) It is not affected by environmental factors and has strong anti-aging ability, which can be used for long-term monitoring. 3) The wireless sensor is used to collect the voltage value, which is not restricted by the position of the rod, and does not need to arrange super long data lines, which is convenient for carrying out experiments. 4) High safety: The force on the rod can be calculated in real time by dynamically monitoring the voltage at both ends of the piezoelectric ceramic rod, which can improve the safety of the structure during use.

Description of drawings

Fig. 1 is a plane view of a single-layer spherical reticulated shell with a piezoelectric ceramic rod structure provided by the present invention.

Fig. 2 is a sectional view along A-A in Fig. 1 .

Fig. 3 is a schematic diagram of the structure of the ceramic rod connector connected to the end of the upper chord, lower chord or diagonal rod in the single-layer spherical reticulated shell with piezoelectric ceramic rod structure provided by the present invention.

Fig. 4 is a schematic diagram of the structure of the bolt ball node in the piezoelectric ceramic rod structure single-layer spherical reticulated shell provided by the present invention.

Fig. 5 is a graph of the natural vibration frequency of the piezoelectric ceramic rod structure single-layer spherical reticulated shell and the steel structure single-layer spherical reticulated shell provided by the present invention.

Fig. 6 is a vertical displacement curve diagram of the piezoelectric ceramic rod structure single-layer spherical reticulated shell and the steel structure single-layer spherical reticulated shell provided by the present invention.

Fig. 7 is a block diagram of the internal force monitoring device of the rod on the piezoelectric ceramic rod structure single-layer spherical reticulated shell provided by the present invention.

Detailed ways

The single-layer and double-layer spherical reticulated shell with piezoelectric ceramic rod structure and the internal force monitoring device for the rod provided by the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

As shown in Figures 1 to 4, the piezoelectric ceramic rod structure single-layer spherical reticulated shell provided by the present invention includes a plurality of upper chords 1, a plurality of lower chords 2, a plurality of oblique webs 3, and a plurality of ceramic rod connectors 4. Multiple bolt ball joints 5, several sliding hinge supports 6 and several fixed hinge supports 7; the upper chord 1, lower chord 2 and diagonal web 3 are piezoelectric ceramic rods, and each upper chord 1 A ceramic rod connector 4 is respectively installed at both ends of the lower chord 2 and the diagonal rod 3; the multiple upper chords 1, the multiple lower chords 2 and the multiple diagonal rods 3 with the ceramic rod connector 4 utilize multiple A bolt ball node 5 is connected into a single-layer spherical reticulated shell main body of a traditional shape; the ceramic rod connector 4 includes a plurality of embedded bolts 8, end plates 9, cone heads 10 and a plurality of nuts 11; wherein a plurality of The pre-embedded bolts 8 are installed on the outer edge of the upper chord 1, the lower chord 2 or the diagonal web 3; a plurality of round holes corresponding to the positions of the pre-embedded bolts 8 are formed on the end plate 9, and are fixed on the The outer end surface of the upper chord 1, the lower chord 2 or the oblique web 3; the conical head 10 is a hollow circular platform structure, a round hole 12 is formed in the middle of the upper bottom surface, the lower bottom surface is open, and the edge of the lower bottom surface is connected to the end plate 9 on the outer end edge; each bolt ball node 5 includes a plurality of high-strength bolts 13, a plurality of sealing plates 14, a plurality of sleeves 15, a plurality of pins 16 and a steel ball 17; wherein the screw on the high-strength bolt 13 runs through Set in the circular hole 12 on the cone head 10, and the bolt head is located inside the cone head 10, and a blind hole is formed radially on the outer peripheral surface of the middle part of the screw; the sealing plate 14 is installed on the upper bottom surface of the cone head 10 There is a screw hole formed on the outside, and the central part; the sleeve 15 is set on the screw rod outside the sealing plate 14 on the high-strength bolt 13, and a pin hole is formed on the circumferential surface of the sleeve 15; the front end of the pin 16 passes through The pin holes on the sleeve 15 are inserted into the blind holes on the high-strength bolts 13; multiple round holes are formed on the steel ball 17 for inserting the front ends of the screw rods on multiple high-strength bolts 13; several fixed hinge supports 7 The upper ends of several sliding hinge supports 6 are installed on the other upper chord bolt ball nodes of the main body of the reticulated shell at intervals, and the lower ends are fixed on the top of the structural column. Removably set on top of structural columns.

The upper chord 1, the lower chord 2 and the diagonal web 3 are all hollow piezoelectric ceramic round rods, which not only can reduce the overall weight of the whole structure, but also can reduce the cost.

The number of embedded bolts 8 and nuts 11 on each bolt ball node 5 is 5-7.

The outer surfaces of the embedded bolts 8 and the end plates 9 are coated with an insulating coating.

The assembly process of the single-layer and double-layer spherical reticulated shell with piezoelectric ceramic rod structure provided by the present invention is as follows:

1) According to the design requirements of the piezoelectric ceramic rod structure single-layer spherical reticulated shell, determine the geometric dimensions of the upper chord 1, the lower chord 2 and the diagonal 3, and process the upper chord 1, the lower chord 2 and the diagonal 3 During the process, a plurality of embedded bolts 8 are set on the edges of the two outer ends;

2) Using a plurality of nuts 11 to fix an end plate 9 on an outer end surface of each upper chord 1, lower chord 2 or diagonal web 3;

3) The screw rod on the high-strength bolt 13 is penetrated and arranged in the circular hole 12 on the cone head 10, and the bolt head is positioned at the inside of the cone head 10;

4) Connect the high-strength bolts 13 in the conical head 10 at the two ends of the upper chord 1, the lower chord 2, or the oblique web 3 at different spatial angles to a bolt ball node 5, thereby making a traditional single-layer double-layer The main body of the spherical reticulated shell;

5) Install the upper ends of a plurality of fixed hinge supports 7 on the upper chord bolt ball node 5 on one side of the reticulated shell main body at a distance, and fix the lower end on the top of the structural column; install the upper ends of a plurality of sliding hinge supports 6 at a distance The upper and lower ends of the other upper chord bolt ball joints 5 of the main body of the reticulated shell are movably arranged on the top of the structural column, thereby forming the single-layer spherical reticulated shell with piezoelectric ceramic rod structure.

In order to analyze the seismic performance of the piezoelectric ceramic rod structure single-layer spherical reticulated shell provided by the present invention, the applicant used the finite element software ANSYS to compare the piezoelectric ceramic rod structure single-layer spherical reticulated shell and the same appearance size and cross-sectional area. The first 8 natural frequencies of the steel structure single-layer spherical reticulated shell and the vertical displacement change within 8 seconds under the action of the horizontal seismic EL-Centro (1940) wave, the results are shown in Figure 5 and Figure 6. It can be seen from Figure 5 that the first three natural frequencies of the two are relatively close, indicating that the dynamic characteristics of the piezoelectric ceramic rod structure single-layer spherical reticulated shell and the steel structure single-layer spherical reticulated shell are similar. It can be seen from Figure 6 that the amplitude of the displacement change of the piezoelectric ceramic rod structure single-layer spherical reticulated shell under the earthquake is slightly smaller than that of the steel structure single-layer spherical reticulated shell. This is caused by the light weight of the structure itself, which means that the earthquake Under the action, the single-layer and double-layer spherical reticulated shell with piezoelectric ceramic rod structure has good anti-seismic performance. It can be seen from the above calculation and analysis that the piezoelectric ceramic rod structure single-layer spherical reticulated shell provided by the present invention is safe and reliable.

As shown in Figure 7, the internal force monitoring device of the rod on the piezoelectric ceramic rod structure single-layer spherical reticulated shell provided by the present invention includes a wireless sensor 18, a data receiving base station 19, a data analyzer 20 and a wire 21; wherein each upper chord 1. A wireless sensor 18 is respectively installed on the lower chord 2 and the diagonal rod 3. At the same time, two wires 21 are preset on each upper chord 1, lower chord 2 and diagonal rod 3, and one end of each wire 21 is connected to At one end of the upper chord 1, the lower chord 2 and the diagonal rod 3, the other end is connected with the wireless sensor 18; the wireless sensor 18 is wirelessly connected with the data receiving base station 19 arranged on the ground; and the data receiving base station 19 and the data analyzer 20 are connected by data lines.

Now the working principle of the internal force monitoring device on the rod on the piezoelectric ceramic rod structure single-layer spherical reticulated shell provided by the present invention is described as follows: During the use of the above-mentioned piezoelectric ceramic rod structure single-layer spherical reticulated shell, the wireless sensor 18 will real-time Collect the electrical pressure difference at both ends of the upper chord 1, the lower chord 2 and the diagonal 3, and wirelessly transmit the detection value to the data receiving base station 19; the data receiving base station 19 transmits the data collected by multiple wireless sensors 18 to the data analysis 20, the data analyzer 20 calculates the internal force value of the rod under the dynamic load according to the above-mentioned detection value and the design parameters of each upper chord 1, lower chord 2 and diagonal rod 3, thereby realizing the structural analysis of the piezoelectric ceramic rod Dynamic monitoring of the internal force of the rod on the double-layer spherical reticulated shell.

Claims (5)

1. A piezoelectric ceramic rod structure single-layer spherical reticulated shell is characterized in that: the piezoelectric ceramic rod structure single-layer spherical reticulated shell comprises a plurality of upper chords (1) and a plurality of lower chords (2) , multiple diagonal web bars (3), multiple ceramic rod connectors (4), multiple bolted ball joints (5), several sliding hinge supports (6) and several fixed hinge supports (7); The upper chord (1), the lower chord (2) and the diagonal rod (3) are piezoelectric ceramic rods, and the two ends of each upper chord (1), lower chord (2) and diagonal rod (3) are respectively installed There is one ceramic rod connector (4); multiple top chords (1), multiple bottom chords (2) and multiple diagonal rods (3) with ceramic rod connectors (4) utilize multiple bolted ball joints (5) The main body of a single-layer spherical reticulated shell connected into a traditional shape; the ceramic rod connector (4) includes a plurality of embedded bolts (8), end plates (9), cone heads (10) and a plurality of Nut (11); wherein a plurality of pre-embedded bolts (8) are installed on the edge of the outer end of the upper chord (1), the lower chord (2) or the diagonal web (3); the end plate (9) is formed with multiple A round hole corresponding to the position of the embedded bolt (8), fixed on the outer end surface of the upper chord (1), the lower chord (2) or the diagonal rod (3) by a nut (11); the cone head (10) It is a hollow circular platform structure, a circular hole (12) is formed in the middle of the upper bottom surface, the lower bottom surface is open, and the edge of the lower bottom surface is connected to the outer end edge of the end plate (9); each bolt ball node (5) includes A plurality of high-strength bolts (13), a plurality of sealing plates (14), a plurality of sleeves (15), a plurality of pins (16) and a steel ball (17); wherein the screw rods on the high-strength bolts (13) are set through the In the circular hole (12) on the cone head (10), and the bolt head is located in the inside of the cone head (10), and a blind hole is formed radially on the outer peripheral surface of the middle part of the screw rod; the sealing plate (14) is installed on The upper bottom surface of the cone head (10) is outside, and a screw hole is formed in the center; the sleeve (15) is sleeved on the high-strength bolt (13) and is located on the screw rod outside the sealing plate (14), and the sleeve (15) A pin hole is formed on the circumferential surface; the front end of the pin (16) passes through the pin hole on the sleeve (15) and is inserted into the blind hole on the high-strength bolt (13); multiple pin holes are formed on the steel ball (17). A round hole is used to insert the front ends of the upper screw rods of multiple high-strength bolts (13); the upper ends of several fixed hinge supports (7) are installed on the upper chord bolt ball joints on one side of the main body of the reticulated shell at intervals, and the lower ends are fixed on the structure The top of the column; the upper ends of several sliding hinge supports (6) are installed on the remaining upper chord bolt ball joints of the main body of the reticulated shell at a distance, and the lower ends are arranged on the top of the structural column in a movable manner. 2. The piezoelectric ceramic rod structure single-layer spherical reticulated shell according to claim 1, characterized in that: the upper chord (1), the lower chord (2) and the diagonal rod (3) are all hollow pressure Electroceramic round rod. 3. The piezoelectric ceramic rod structure single-layer spherical reticulated shell according to claim 1, characterized in that: the number of embedded bolts (8) and nuts (11) on each bolt ball node (5) for 5-7. 4. The piezoelectric ceramic rod structure single-layer spherical reticulated shell according to claim 1, characterized in that: the outer surfaces of the embedded bolts (8) and the end plates (9) are coated with an insulating coating . 5. A rod member internal force monitoring device on a piezoelectric ceramic rod structure single-layer spherical reticulated shell as claimed in claim 1, characterized in that: the rod member internal force monitoring device includes a wireless sensor (18), a data receiving device Base station (19), data analyzer (20) and wire (21); wherein each upper chord (1), lower chord (2) and diagonal pole (3) are respectively equipped with a wireless sensor (18), while Two wires (21) are preset on each upper chord (1), lower chord (2) and diagonal rod (3), and one end of each wire (21) is connected to upper chord (1), lower chord ( 2) and one end of the diagonal pole (3), the other end joins with the wireless sensor (18); the wireless sensor (18) is wirelessly connected with the data receiving base station (19) arranged on the ground; and the data receiving base station (19) It is then connected with the data analyzer (20) through a data line.

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