Periodic resonator vibration reduction and isolation system and installation method

Abstract

A periodic resonator vibration reduction and isolation system comprises a vibration reduction and isolation system body arranged in a soil body between a vibration source and a protected building, the vibration reduction and isolation system body comprises vibration reduction and isolation holes which are evenly distributed in the soil body, a resonator is arranged in each vibration reduction and isolation hole, and the vibration reduction and isolation holes are arranged in three or four rows in an alternating circulation extending mode. The connecting lines of the center points of the vibration reduction and isolation holes form an angle of 60 degrees R. The hole distance L of the vibration reduction and isolation holes is not smaller than 1 / 4 of the wavelength of a vibration source. The resonator comprises a tubular body, a first cavity, a second cavity and a third cavity are sequentially formed in the tubular body in the vibration propagation direction, a rigid spring vibrator is arranged in the third cavity, and the rigid spring vibrator is arranged in the second cavity. Rubber blocks are arranged at the upper end and the lower end of the third cavity respectively, the upper end and the lower end of the rigid spring vibrator are connected to the rubber blocks respectively, and the upper end and the lower end of the tubular body are fixed into the vibration reduction and isolation holes through the upper concrete layer and the lower concrete layer.

Description

Technical Field

[0001] This invention relates to the field of vibration reduction and isolation technology, and in particular to a periodic resonator vibration reduction and isolation system based on ancient buildings and its installation method. Background Technology

[0002] With my country's rapid economic development and the continuous improvement of people's living standards, urban traffic congestion has intensified. To alleviate urban traffic pressure, urban transportation methods have become increasingly diverse. Besides conventional road traffic, underground transportation is gradually becoming a major mode of transportation to alleviate traffic pressure. The role of underground railway construction in alleviating road congestion is obvious. In my country, underground railway construction generally relies on tunnel boring machines (TBMs). However, the vibrations generated during TBM tunneling greatly affect people's normal lives and even threaten life and property safety. The vibrations generated during TBM tunneling can cause varying degrees of damage to surrounding buildings. If the vibration source is near precision instruments such as electron optics and electron microscopy laboratories, biomedical imaging centers, and nuclear magnetic resonance imaging research centers, it will significantly affect the accuracy of scientific instruments, seriously impacting normal scientific research. In conclusion, the importance of vibration reduction and isolation measures for underground transportation construction is self-evident.

[0003] Because the vibrations are generated in different ways, the frequencies of the vibrations emitted by the vibration sources are also different. For example, the main frequency of the vibration generated during pile driving is generally 20-30 Hz, while the main frequency of the vibration generated during shield tunneling is generally lower than 20 Hz. The main frequencies of vibrations in road traffic and underground traffic are 0-10 Hz and 40-100 Hz, respectively.

[0004] Therefore, scientists are striving to explore various vibration reduction and isolation measures, such as trenches, filled trenches, piles, various vibration isolation bearings, and other vibration isolation barriers that isolate vibrations. These measures often effectively reduce and isolate vibrations. However, adding vibration isolation bearings to older buildings presents significant challenges and requires substantial manpower and financial resources. While vibration isolation trenches and piles generally provide good reduction for high-frequency vibrations, their effectiveness against low-frequency vibrations generated by tunnel boring machines (TBMs) is limited. Furthermore, in some special buildings, such as research sites or near ancient buildings, conventional vibration reduction measures can actually produce greater vibrations than those generated by TBM construction, failing to fundamentally reduce or isolate vibrations. Summary of the Invention

[0005] To overcome the above problems, the present invention provides a periodic resonator vibration reduction and isolation system applicable to low-frequency vibrations generated by a series of construction projects, as well as high-frequency vibrations caused by factors such as underground traffic.

[0006] Another object of the present invention is to provide an installation method for a periodic resonator vibration reduction and isolation system.

[0007] The technical solution adopted in this invention is as follows: a vibration reduction and isolation system is set in the soil between the vibration source and the protected building. The vibration reduction and isolation system includes uniformly distributed vibration reduction and isolation holes in the soil. A resonator is set in each vibration reduction and isolation hole. The vibration reduction and isolation holes are arranged in three or four alternating cyclic extensions. The line connecting the center points of each vibration reduction and isolation hole forms a 60°R angle with each other. The hole spacing L of each vibration reduction and isolation hole is not less than 1 / 4 of the wavelength of the vibration source. The resonator includes a tubular body. A first cavity, a second cavity, and a third cavity are arranged sequentially in the tubular body along the vibration propagation direction. A rigid spring oscillator is set in the third cavity. Rubber blocks are set at the upper and lower ends of the third cavity. The upper and lower ends of the rigid spring oscillator are respectively connected to the rubber blocks. The upper and lower ends of the tubular body are fixed in the vibration reduction and isolation holes by an upper concrete layer and a lower concrete layer.

[0008] Furthermore, the tubular body is a PVC pipe, and the wall thickness H2 of the PVC pipe is 10mm.

[0009] Furthermore, the depth H1 of the vibration reduction and isolation hole is 3000mm, the hole diameter Φ is 300mm, and the height and diameter of the resonator are the same as those of the vibration reduction and isolation hole.

[0010] The present invention provides an installation method for a periodic resonator vibration reduction and isolation system. Step 1: Pre-set the positions of vibration reduction and isolation holes on the ground between the vibration source and the protected building. The holes are arranged in three or four alternating and cyclical rows. The angle between the lines connecting the centers of each hole is 60°R. The distance between the holes L is not less than 1 / 4 of the wavelength of the vibration source. Step 2: Drag the prefabricated resonator from the factory to the vibrating hole area, and move the resonator next to the prefabricated vibration reduction and isolation hole before drilling. Step 3: A hydraulic drilling machine is used to drill holes in the soil at the pre-set vibration reduction and isolation hole locations. The depth H1 of the vibration reduction and isolation hole is 3000mm and the hole diameter Φ is 300mm. Step 4: Immediately after drilling is completed, pour the lower concrete layer into the vibration reduction and isolation hole. After the lower concrete layer has partially solidified, insert the resonator in the middle of the lower concrete layer. Step 5: Fill the upper part of the resonator with a concrete layer. After the concrete has solidified, restore the surface of the upper concrete layer to its original shape.

[0011] The present invention provides a periodic resonator vibration reduction and isolation system and installation method, the advantages of which are: I. Most existing vibration reduction systems are designed for high-frequency vibrations and are ineffective at isolating low-frequency vibrations during tunnel boring machine (TBM) excavation. This solution pre-installs periodically arranged vibration-damping holes along the propagation path between the vibration source and the protected ancient building. Resonators are installed in these holes. The inherent openings of the holes cause the elastic waves generated by the vibration source to be reflected and scattered between them, resulting in geometric damping and energy attenuation. The resonators feature a labyrinthine cavity design for air channels. This design significantly increases the length of the original air channels without reducing the internal volume, greatly reducing vibration energy after passing through the first and second cavities. The rigid spring oscillator in the third cavity also significantly reduces vibrations at specific frequencies. The first and second cavities are left empty, further effectively weakening high-frequency vibrations and enhancing the vibration isolation effect of the periodic resonator system. Meanwhile, the periodically arranged resonator vibration reduction and isolation system possesses a high-frequency attenuation domain. By controlling the spacing between the vibration reduction and isolation holes, targeted isolation of vibrations at different wavelengths can be achieved, thus isolating vibrations of specific frequencies. Furthermore, the spring resonant frequency can be controlled by adjusting the total number of turns, inner and outer diameters of the rigid spring oscillator, and the rigidity modulus of the material, enabling highly efficient vibration reduction and isolation for certain low-frequency vibrations. Compared to isolating single-frequency vibrations, this vibration reduction and isolation system can achieve effective isolation across multiple frequency bands.

[0012] Second, during the construction process, a reasonable design was made for the construction layout of the periodic vibration reduction and isolation holes. That is, before the vibration source starts to vibrate, the drilling is carried out by a hydraulic drilling machine. Because a specific hydraulic drilling machine is used, the vibration generated during the drilling process is small and has a negligible impact on the protected building. Moreover, the prefabricated vibration reduction and isolation holes do not require frequent maintenance or repair in the later stage, which does not affect the construction progress, reduces maintenance costs, and improves economic efficiency.

[0013] Third, this method has a simple installation process, low assembly requirements, and a stable structure. The total number of turns, inner and outer diameters, and materials of the rigid spring oscillator can be adjusted according to the frequency and wavelength of the vibration generated by the vibration source to control its spring resonance frequency. This can greatly reduce the impact of the vibration source on the protected building. Based on the characteristics of this resonator, it is possible to carry out systematic production and assembly.

[0014] IV. The resonator in this scheme includes a tubular body, which can be made of high-polymer PVC pipe as an external support. The material has good stability, which can effectively prevent the soil around the vibration reduction and isolation holes from collapsing. It also has excellent dielectric and mechanical properties, and can be easily removed and backfilled after construction, thus having a small impact on the environment around the ancient building. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the distribution of the periodic resonator vibration reduction and isolation system of the present invention; Figure 2 yes Figure 1 A schematic diagram of section A-A; Figure 3 This is a schematic diagram of the resonator structure of the present invention. Detailed Implementation

[0016] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0018] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0019] like Figure 1 — Figure 3As shown, this invention discloses a periodic resonator vibration reduction and isolation system, comprising a vibration reduction and isolation system installed in the soil 3 between a vibration source 1 and a protected building 2. The vibration reduction and isolation system includes uniformly distributed vibration reduction and isolation holes 4 in the soil 3, with a resonator 5 installed in each vibration reduction and isolation hole 4. The vibration reduction and isolation holes 4 are arranged in three or four alternating cyclic extensions, and the lines connecting the center points of each vibration reduction and isolation hole 4 form a 60°R angle with each other. The hole spacing L of each vibration reduction and isolation hole 4 is not less than 1 / 4 of the wavelength of the vibration source. The resonator 5 includes a tubular body 6, in which first cavities 7 are sequentially arranged along the vibration propagation direction. The system comprises a second cavity 8 and a third cavity 9. A rigid spring vibrator 10 is installed in the third cavity. Rubber blocks 11 are installed at both the upper and lower ends of the third cavity 9. The upper and lower ends of the rigid spring vibrator 10 are respectively connected to the rubber blocks 11. The tubular body 6 is a PVC pipe with a wall thickness H2 of 10 mm. The depth H1 of the vibration damping hole is 3000 mm, and the hole diameter Φ1 is 300 mm. The height and diameter of the tubular body 6 are the same as those of the vibration damping hole. The upper and lower ends of the tubular body 6 are fixed in the vibration damping hole 4 by an upper concrete layer 12 and a lower concrete layer 13. The tubular body 6 is a PVC pipe with a pipe diameter Φ2 of 10 mm.

[0020] The periodic resonator vibration reduction and isolation system described in this scheme uses a hydraulic drilling machine to excavate the soil along the path of the vibration source in the ancient building. Several cylindrical vertical vibration reduction and isolation holes 4 are excavated in a periodic honeycomb pattern. The depth of these holes is generally not less than the depth of the vibration source. The lines connecting the center points of each vibration reduction and isolation hole form a 60-degree angle with each other, i.e., a honeycomb distribution. This greatly extends the propagation path of the vibration in the soil. The diameter Φ of the vibration reduction and isolation holes 4 is 300mm, and the hole spacing is determined according to the wavelength, generally not less than the wavelength. .

[0021] The resonator is wrapped with a high-polymer PVC tubular body 6 of the same diameter as the vibration reduction and isolation hole, and three cavities are isolated therein, namely the first cavity 7, the second cavity 8 and the third cavity 9 along the vibration propagation direction. A rigid spring oscillator 10 is set in the third cavity 9. The two ends of the rigid spring oscillator are respectively connected to the rubber block 11 to ensure that the structure remains stable after the rigid spring oscillator 10 resonates due to the vibration of its unique frequency.

[0022] For a rigid spring oscillator, its natural frequency is controlled by the following formula:

[0023] In the formula: denoted as , where is the natural frequency of the rigid spring oscillator; k is the spring constant of the rigid spring oscillator (in N / m); and m is the weight of the rigid spring oscillator (in kg). To ensure the overall stability of the resonator structure under vibration and soil pressure, its external cladding material is a high-polymer PVC tubular body with a wall thickness H2 typically around 10mm. To ensure effective vibration reduction and isolation for some high-frequency vibrations, the first cavity 7 and the second cavity 8 are not filled with any medium, thus ensuring effective isolation of high-frequency vibrations. The rigid spring oscillator 10 in the third cavity 9 is fixed at both ends by rubber blocks 11, forming a whole. This structure can be prefabricated in the factory. The material for the rigid spring oscillator can be selected from high-quality carbon steel, alloy steel, or non-ferrous metal alloy stainless steel. Example 1

[0024] This embodiment aims to analyze the diameter of the vibration reduction and isolation hole 4, the hole spacing of each vibration reduction and isolation hole, and the resonance frequency of the rigid spring oscillator 10 using a specific embodiment. In this embodiment

[0025] The distance between the vibration source and the protected building is D=5200mm, and the burial depth of the vibration source is 1010mm.

[0026] The main frequency generated by the vibration source is 0-20Hz, the wave speed is 300m, and the wavelength is about 15m.

[0027] Based on the basic information from the embodiment, we can obtain: Hole spacing =

[0028] The construction data of a rigid spring oscillator can be calculated using the following formula.

[0029]

[0030] but:

[0031] Vibration frequency (Hz) <![CDATA[Single spring stiffness K 1 (N / m)]]> 5 <![CDATA[2.604×10 5 ]]> 20 <![CDATA[4.167×10 6 ]]> In this embodiment, the vibration frequency range is 5Hz to 20Hz. The spring specifications can be selected according to the table above. To ensure the system operates safely and achieves a good vibration reduction effect, the spring stiffness is greater than 2.604 × 10⁻⁶. 7 N / m.

[0032] In summary, the working principle of the periodic resonator vibration reduction and isolation system designed in this invention is as follows: When vibrations caused by construction and other factors propagate to the periodic resonator vibration reduction and isolation system, the vibration reduction and isolation holes of the resonator reflect the vibrations. Furthermore, their periodic arrangement greatly extends the propagation path of the vibrations, and the reflected vibrations cancel each other out due to the honeycomb structure, thus significantly weakening the vibration energy. Additionally, the use of a specific resonator inside the vibration reduction and isolation holes, with two labyrinthine cavities (the first and second cavities), greatly increases the length of the air passage. A rigid spring oscillator of a specific frequency is installed in the third cavity, which can be excited by the specific dominant frequency of the vibration to induce resonance, greatly reducing the vibration energy and effectively weakening vibrations at various frequencies.

[0033] In ancient buildings and vibration source propagation paths, this resonator vibration reduction and isolation system employs a periodic honeycomb arrangement to significantly extend the vibration propagation path. Furthermore, the vibrations weaken each other within the individual vibration reduction and isolation holes, greatly reducing and isolating vibration energy. The tubular body supporting the vibration reduction and isolation holes is made of high-polymer PVC pipe, possessing excellent stability and effectively preventing soil collapse around the holes. This maintains a cavity within the holes, providing better attenuation and isolation of high-frequency vibrations generated by the vibration source.

[0034] When the vibration source begins to vibrate, the vibration propagates through the ancient building and the soil within the vibration source. During propagation, the periodic resonator vibration reduction and isolation system reflects and weakens the vibration. However, some vibration wave energy still passes through the first row of resonators. After passing through the air channels in the first and second cavities, the energy of the vibration is significantly reduced. The vibration then excites the rigid spring oscillator 10 located in the third cavity to resonate, further weakening the vibration. Simultaneously, the vibrations passing through the first row of resonators are also weakened by the multiple scattering of the honeycomb-shaped periodic structure and the energy absorption effect of the cavities within the resonators, thus reducing or even isolating the vibration generated by the vibration source.

[0035] The present invention provides an installation method for a periodic resonator vibration reduction and isolation system. Step 1: Pre-set the positions of vibration reduction and isolation holes on the ground between the vibration source and the protected building. The holes are arranged in three or four alternating and cyclical rows. The angle between the lines connecting the centers of each hole is 60°R. The distance between the holes L is not less than 1 / 4 of the wavelength of the vibration source. Step 2: Drag the prefabricated resonator from the factory to the vibrating hole area, and move the resonator next to the prefabricated vibration reduction and isolation hole before drilling. Step 3: A hydraulic drilling machine is used to drill holes in the soil at the pre-set vibration reduction and isolation hole locations. The depth H1 of the vibration reduction and isolation hole is 3000mm and the hole diameter Φ is 300mm. Step 4: Immediately after drilling is completed, pour the lower concrete layer into the vibration reduction and isolation hole. After the lower concrete layer has partially solidified, insert the resonator in the middle of the lower concrete layer. Step 5: Fill the upper part of the resonator with a concrete layer. After the concrete has solidified, restore the surface of the upper concrete layer to its original shape.

[0036] In actual construction, before drilling, the distribution of vibration reduction and isolation holes 4 should be reasonably planned between the vibration source and the protected building. That is, the positions of vibration reduction and isolation holes 4 should be preset on the ground between the vibration source and the protected building. Then, the resonators 5 prefabricated in the factory should be dragged to the pre-designed drilling site. Before drilling, the resonators 5 should be placed next to the preset drilling positions. Then, the hydraulic drilling machine should be used to drill the soil. After drilling is completed, the lower concrete layer 13 should be filled into each vibration reduction and isolation hole 4. After the lower concrete layer 13 is semi-solidified, the resonator 5 should be inserted into it. Then, the concrete layer 12 should be backfilled on top of the resonator 5. After the upper and lower concrete layers are solidified, the soil above should be restored to reduce the impact on the environment.

[0037] The embodiments described in this specification are merely examples of implementations of the inventive concept. The scope of protection of this invention should not be considered as limited to the specific forms stated in the embodiments. The scope of protection of this invention also extends to equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. A periodic resonator vibration reduction and isolation system, characterized in that: The invention comprises a vibration reduction and isolation system arranged in the soil between the vibration source and the protected building, wherein the vibration reduction and isolation system comprises uniformly distributed vibration reduction and isolation holes arranged in the soil, a resonator arranged in each vibration reduction and isolation hole, the vibration reduction and isolation holes are arranged in three or four rows and extended alternately and cyclically, the central points of each vibration reduction and isolation hole are connected at an angle of 60°R to each other, the hole spacing L of each vibration reduction and isolation hole is not less than 1 / 4 of the wavelength of the vibration source, the resonator comprises a tubular body, a first cavity, a second cavity and a third cavity are arranged in sequence in the tubular body along the vibration propagation direction, a rigid spring vibrator is arranged in the third cavity, rubber blocks are arranged at the upper and lower ends of the third cavity, the upper and lower ends of the rigid spring vibrator are respectively connected to the rubber blocks, and the upper and lower ends of the tubular body are fixed in the vibration reduction and isolation holes by an upper concrete layer and a lower concrete layer.

2. A periodic resonator vibration reduction and isolation system as claimed in claim 1, characterized in that The tubular body is a PVC tube, and the tube wall thickness H2 of the PVC tube is 10 mm.

3. A periodic resonator vibration reduction and isolation system as claimed in claim 1, characterized in that The depth H1 of the vibration reduction and isolation hole is 3000 mm, the hole diameter Φ is 300 mm, and the height and diameter of the resonator are the same as those of the vibration reduction and isolation hole.

4. A method for installing a periodic resonator vibration reduction and isolation system, characterized in that: Step 1: Preset the vibration reduction and isolation holes on the ground between the vibration source and the protected building. The holes of the vibration reduction and isolation holes are arranged in three or four rows, alternating and cyclically extending. The angle between the center of each hole is 60°R, and the hole spacing L is not less than 1 / 4 of the wavelength of the vibration source. Step 2: Drag the resonator prefabricated in the factory to the vicinity of the preset vibration reduction and isolation hole, and move the resonator next to the preset vibration reduction and isolation hole before drilling; Step 3: Use a hydraulic drilling machine to drill holes in the soil at the preset vibration reduction and isolation hole locations. The depth H1 of the vibration reduction and isolation holes is 3000 mm, and the hole diameter Φ is 300 mm. Step 4: After the drilling is completed, pour the lower concrete layer in the vibration reduction hole immediately. After the lower concrete layer is semi-solidified, insert the resonator in the middle of the lower concrete layer; Step 5: Fill the upper end of the resonator with an upper concrete layer, and after the concrete solidifies, restore the surface of the upper concrete layer to its original geomorphology.

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