A building vibration isolation method for environmental vibration control

Abstract

The present invention discloses a building vibration isolation method for environmental vibration control, including: obtaining the building foundation compressive stress and the building foundation outer wall pressure, and constructing corresponding building base compressive stress diagrams and building lateral pressure diagrams; determining the types and mechanical parameters of the building bottom pads and building side pads respectively according to the building base compressive stress diagrams and building lateral pressure diagrams, and based on the deformation rates of the vibration isolation pad materials under the corresponding pressures; drawing the paving diagram of the elastic pads at the bottom of the foundation according to the distribution of the building foundation compressive stress and the geometric dimensions of the building bottom pads; drawing the paving diagram of the elastic pads on the outer wall of the foundation according to the distribution of the building foundation outer wall pressure and the geometric dimensions of the building side pads; and performing paving according to the paving diagram of the elastic pads at the bottom of the foundation and the paving diagram of the elastic pads on the outer wall of the foundation to achieve building vibration isolation. This method stipulates the basis and principles for the selection of building foundation vibration isolation pad materials, and can make the vibration isolation pads more suitable for the upper vibration isolation building, achieving a better vibration isolation effect.

Description

Technical Field

[0001] The present invention relates to the technical field of building vibration isolation, and more specifically to a building vibration isolation method for environmental vibration control. Background Art

[0002] In order to reduce the influence of rail transit on indoor vibration noise of buildings along the line, it is necessary to adopt building body vibration isolation measures for sensitive buildings constructed in the vicinity of the line at a short distance. The environmental impact of the subway is mainly vertical vibration, and the main vibration frequency range is about 20 - 60 Hz. According to the vibration isolation theory, the control of high-frequency subway vibration can be achieved by adjusting and reducing the overall vertical natural frequency of the building structure. The effect of this vibration isolation method can be evaluated by the vibration transmission ratio, and this vibration transmission ratio is expressed as:

[0003]

[0004] Among them, η represents the vibration transmission ratio; ζ represents the damping ratio; f represents the subway vertical vibration excitation frequency; f0 represents the overall vertical natural frequency of the vibration isolation building.

[0005] Figure 1 is a curve graph of the functional relationship between the vibration transmission ratio provided by the related prior art and the frequency ratio (f / f0). It can be seen from Figure 1 that when the frequency ratio (f / f0) is 1, the vibration transmission ratio is the largest, and a resonance response occurs; when the frequency ratio (f / f0) is greater than 1, the vibration transmission ratio is less than 1, entering the vibration isolation area, and the larger the frequency ratio, the smaller the vibration transmission ratio, that is, the better the vibration isolation effect; in addition, the damping ratio also affects the vibration isolation effect. In the vibration isolation area, the vibration isolation effect is inversely proportional to the damping ratio, and in the resonance area, the vibration isolation effect is directly proportional to the damping ratio.

[0006] According to the above vibration isolation principle, an elastic cushion can be laid at the bottom of the building foundation, and the vertical natural frequency of the "building - elastic cushion" system can be adjusted by designing the parameters of the elastic cushion, so as to reduce the influence of subway vibration on the upper building structure. Therefore, for newly built building projects near subway lines, the foundation elastic cushion is an effective and feasible building body vibration isolation measure with extremely broad application prospects.

[0007] Figure 2Schematic diagram of vibration isolation of a single building foundation elastic pad provided for the relevant existing technology. The vibration isolation design of the elastic pad is relatively simple, and the control effect is easy to ensure. However, the above-ground and underground space designs of modern buildings are more complex and diverse. Complexes with different structural forms and storeys share the underground foundation, and the distribution of the bearing pressure at the building base is extremely uneven. How to accurately regulate the vertical natural frequency of complex above-ground and underground buildings (groups) is the main problem faced by building vibration isolation design. On the other hand, the elastic pad is located at the bottom of the building foundation, cannot be replaced or repaired, and is in a complex groundwater and geotechnical environment. Coupled with the long-term repeated broadband subway loads, how to ensure the long-term effectiveness of the elastic pad during the entire life cycle of the building (usually more than 50 years) has always been a key concern. Therefore, although the building foundation elastic pad, as a control measure for subway environmental vibration, has been gradually recognized by people, for complex building structural systems and the actual working environmental conditions of the elastic pad, there is still a lack of refined elastic pad design methods and technical index requirements for guiding engineering applications.

[0008] In summary, the vibration isolation principle of the building foundation elastic pad control measure is simple, and the elastic pad can be paved conveniently and quickly, gradually becoming one of the important subway vibration control measures in China. However, in the actual engineering project application, people assume the "building-elastic pad" as an ideal single-degree-of-freedom "mass-spring" system, and carry out elastic pad vibration isolation design and effect evaluation based on the above vibration transfer rate formula. However, the actual engineering projects are extremely complex, and the influencing factors of the vibration isolation effect are diverse. On the one hand, currently, building structure groups usually share the underground foundation. The above-ground building structures have various forms and large differences in storeys, and the distribution of the underground foundation pressure is extremely uneven. It is obviously unreasonable to simplify the "building-elastic pad" into an ideal "mass-spring" system because it is impossible to use elastic pad materials with exactly the same mechanical properties in different parts of the building foundation. On the other hand, deep foundation buildings are restricted by the surrounding geotechnical media, and it is difficult for the building itself to form a "completely vertically free state", and corresponding measures need to be taken to ensure the overall vertical displacement of the building. In addition, when the elastic pad is below the groundwater level, the mechanical properties of the elastic pad will change when it is immersed in water (as Figure 3 shown), and at the same time, the upward buoyancy force formed by the groundwater on the building structure also affects the performance of the vibration isolation pad. However, when designing the vibration isolation engineering application of the current building foundation elastic pad, the above comprehensive factors have not been fully considered, and there is a lack of refined design methods for the building foundation elastic pad, ultimately resulting in a large deviation between the control design effect and the actual situation.

[0009] Therefore, in view of the characteristics of the underground environment in the actual application of elastic pads and the complex structural system of building engineering, considering various influencing factors such as the uneven distribution of compressive stress in the underground foundation, groundwater, and the restraint effect of surrounding rock and soil, proposing a more refined method for selecting and designing elastic pads and evaluating their effects, achieving precise control and evaluation of the vertical natural frequency of building structures, clarifying the standard process and key performance index requirements for vibration isolation design of elastic pads, and ensuring the environmental vibration control effect of elastic pads throughout the building's life cycle are issues that need to be urgently solved by those skilled in the art. Summary of the Invention

[0010] In view of the above problems, the present invention provides a building vibration isolation method for environmental vibration control to at least solve some of the technical problems mentioned in the above background art.

[0011] To achieve the above object, the present invention adopts the following technical solutions:

[0012] The present invention provides a building vibration isolation method for environmental vibration control, including the following steps:

[0013] Obtain the compressive stress of the building foundation and the pressure on the outer wall of the building foundation, and construct the corresponding building base compressive stress diagram and building lateral pressure diagram;

[0014] According to the building base compressive stress diagram and the building lateral pressure diagram, and based on the deformation rate of the vibration isolation pad material under the corresponding pressure, respectively determine the models and mechanical parameters of the building bottom pad and the building side pad;

[0015] According to the distribution of the compressive stress of the building foundation and the geometric dimensions of the building bottom pad, divide the building base into multiple base grid units, each base grid unit corresponding to a piece of building bottom pad, and draw the paving diagram of the elastic pad at the bottom of the foundation;

[0016] According to the distribution of the pressure on the outer wall of the building foundation and the geometric dimensions of the building side pad, divide the outer wall of the building foundation into multiple lateral grid units, each lateral grid unit corresponding to a piece of building side pad, and draw the paving diagram of the elastic pad on the outer wall of the foundation;

[0017] Perform paving according to the paving diagram of the elastic pad at the bottom of the foundation and the paving diagram of the elastic pad on the outer wall of the foundation to achieve building vibration isolation.

[0018] Furthermore, it further includes the following steps:

[0019] Based on the compressive stress of the building foundation and the paving diagram of the elastic pad at the bottom of the foundation, combined with the dynamic elastic modulus, paving area, and thickness of the building bottom pad, calculate the equivalent stiffness and equivalent mass of the building bottom pad;

[0020] Obtain the vertical natural frequency of the vibration isolation building according to the equivalent stiffness and equivalent mass;

[0021] Modify the vertical natural frequency of the vibration isolation building according to the influence of groundwater.

[0022] Based on the modified vertical natural frequency of the vibration isolation building, obtain the vibration transmission ratio of the vibration isolation building corresponding to different vibration source excitation frequencies.

[0023] Based on the vibration transmission ratio, calculate the vibration reduction amount of the vibration isolation building for different vibration source excitation frequencies.

[0024] Furthermore, combine the earth pressure, water pressure, ground load and civil air defense load on the exterior wall of the building foundation to obtain the pressure on the exterior wall of the building foundation.

[0025] Furthermore, the compressive stress diagram of the building foundation is the quasi-permanent combination compressive stress.

[0026] Furthermore, the quasi-permanent combination compressive stress is 1 times the permanent load + 0.5 times the live load.

[0027] Furthermore, the building bottom pad and the building side pad adopt elastic body materials such as polyurethane or rubber.

[0028] Furthermore, according to the compressive stress diagram of the building foundation and the lateral pressure diagram of the building, and based on the deformation rate of the vibration isolation pad material under the corresponding pressure, determine the models and mechanical parameters of the building bottom pad and the building side pad respectively; specifically including:

[0029] According to the different compressive stresses of the building foundation, divide the compressive stress diagram of the building foundation into multiple foundation areas, and based on the deformation rate of the vibration isolation pad material under the compressive stress of the building foundation, fit and fix different models and mechanical parameters of the building bottom pad in different foundation areas.

[0030] According to the different pressures on the exterior wall of the building foundation, divide the lateral pressure diagram of the building into multiple lateral areas, and based on the deformation rate of the vibration isolation pad material under the pressure on the exterior wall of the building foundation, fit and fix different models and mechanical parameters of the building side pad in different lateral areas.

[0031] Furthermore, the deformation rate of the building bottom pad and the building side pad should be within the range of 7% - 20%, and the optimal working deformation amount is 10%.

[0032] Furthermore:

[0033] (1) The equivalent stiffness of the building bottom pad is expressed as:

[0034]

[0035] (2) The equivalent mass of the building bottom pad is expressed as:

[0036]

[0037] (3) The vertical natural frequency of the vibration isolation building theory is expressed as:

[0038]

[0039] where k eq represents the equivalent stiffness of the building base pad; n represents that a total of n base grid units are divided, that is, a total of n building base pads are required; A i represents the area of the building base pad laid in the i-th base grid unit; E i represents the dynamic elastic modulus of the building base pad laid in the i-th base grid unit; h represents the thickness of the building base pad; m eq represents the equivalent mass of the building base pad; σ i represents the quasi-permanent combined compressive stress corresponding to the i-th base grid unit; g represents the acceleration due to gravity; f0 represents the vertical natural frequency of the vibration isolation building theory.

[0040] Furthermore, the corrected vertical natural frequency of the vibration isolation building is expressed as:

[0041]

[0042] where f 水，0 represents the corrected vertical natural frequency of the vibration isolation building theory according to the influence of groundwater; E 水，i represents the dynamic elastic modulus of the elastic pad material in the saturated water immersion state; ρ 水 represents the density of groundwater; H represents the height difference between the groundwater level and the base of the building raft.

[0043] Through the above technical solutions, it can be seen that compared with the prior art, the present invention discloses a building vibration isolation method for environmental vibration control, which has the following beneficial effects:

[0044] 1. The present invention provides a refined design method for the building foundation vibration isolation pad, stipulates the material selection basis and principles of the building foundation vibration isolation pad, and can make the vibration isolation pad more adaptable to the upper vibration isolation building, achieving a better vibration isolation effect.

[0045] 2. The present invention gives the calculation methods of the equivalent stiffness of the building base vibration isolation pad and the equivalent mass of the upper building in view of the complex base pressure distribution characteristics of the common foundation building group, and considers the estimation method of the vertical natural frequency of the vibration isolation pad building under the action of uneven base pressure of the building;

[0046] 3. The present invention considers the actual working environment characteristics of the vibration isolation pad underground, and gives a method for correcting the vertical natural frequency of the building in view of the adverse influence of groundwater on the control effect of the building foundation vibration isolation pad, which can better reflect the actual vibration isolation effect of the vibration isolation building.

[0047] 4. The present invention provides a refined control effect evaluation prediction and design method for building foundation vibration isolation pads, which can accurately regulate the natural frequency and evaluate the effect of vibration isolation buildings, and guide engineering design applications.

[0048] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the provided drawings without creative efforts.

[0050] Figure 1 It is a schematic diagram of the vibration transmission rate curve provided by the related prior art.

[0051] Figure 2 It is a schematic diagram of vibration isolation of the building foundation elastic cushion provided by the related prior art.

[0052] Figure 3 It is a schematic diagram of the comparison of the mechanical property test curves of saturated, dry, and corroded elastic pads provided by the related prior art.

[0053] Figure 4 It is a schematic diagram of the flow of the building vibration isolation method for environmental vibration control provided by the embodiment of the present invention.

[0054] Figure 5 It is a schematic diagram of the quasi-permanent combined compressive stress of the building foundation provided by the embodiment of the present invention.

[0055] Figure 6 It is a schematic diagram of the lateral pressure of the building foundation exterior wall provided by the embodiment of the present invention.

[0056] Figure 7(a) is a schematic diagram of the quasi-permanent combined compressive stress of the foundation provided by the embodiment of the present invention.

[0057] Figure 7(b) is a schematic diagram of the bottom pad paving grid corresponding to Figure 7(a) provided by the embodiment of the present invention.

[0058] Figure 8 It is a schematic diagram of the corresponding curve between the vertical natural frequency of the vibration isolation building and the thickness of the building bottom pad provided by the embodiment of the present invention.

[0059] Figure 9 It is a schematic diagram of the vibration reduction effect curve of the vibration isolation building under different frequency subway excitation loads provided by the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0060] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0061] An embodiment of the present invention discloses a building vibration isolation method for environmental vibration control. Referring to Figure 4 as shown, it includes the following steps:

[0062] S1. Obtain the building foundation compressive stress and the building foundation exterior wall pressure, and construct the corresponding building base compressive stress diagram and building lateral pressure diagram;

[0063] S2. According to the building base compressive stress diagram and the building lateral pressure diagram, and based on the deformation rate of the vibration isolation pad material under the corresponding pressure, respectively determine the models and mechanical parameters of the building bottom pad and the building side pad;

[0064] S3. According to the distribution of the building foundation compressive stress and the geometric dimensions of the building bottom pad, divide the building base into multiple base grid units, with each base grid unit corresponding to a piece of the building bottom pad, and draw the paving diagram of the elastic pad at the bottom of the foundation;

[0065] S4. According to the distribution of the building foundation exterior wall pressure and the geometric dimensions of the building side pad, divide the building foundation exterior wall into multiple lateral grid units, with each lateral grid unit corresponding to a piece of the building side pad, and draw the paving diagram of the elastic pad on the exterior wall of the foundation;

[0066] S5. Perform paving according to the paving diagram of the elastic pad at the bottom of the foundation and the paving diagram of the elastic pad on the exterior wall of the foundation to achieve building vibration isolation;

[0067] S6. Based on the building foundation compressive stress and the paving diagram of the elastic pad at the bottom of the foundation, combined with the dynamic elastic modulus, paving area and thickness of the building bottom pad, calculate the equivalent stiffness and equivalent mass of the building bottom pad;

[0068] S7. According to the equivalent stiffness and equivalent mass, obtain the vertical natural frequency of the vibration-isolated building;

[0069] S8. Correct the vertical natural frequency of the vibration-isolated building according to the influence of groundwater;

[0070] S9. Based on the corrected vertical natural frequency of the vibration-isolated building, obtain the vibration transmission rate of the vibration-isolated building corresponding to different vibration source excitation frequencies; based on the vibration transmission rate, obtain the vibration reduction amount of the vibration-isolated building for different vibration source excitation frequencies.

[0071] The above-mentioned marks S1 - S9 are only for facilitating subsequent explanations and do not limit the specific execution order of each step. Next, each of the above steps will be described in detail.

[0072] In the above step S1, the building foundation compressive stress and the building foundation exterior wall pressure are obtained, and the corresponding building base compressive stress diagram and building lateral pressure diagram are constructed; specifically:

[0073] The building base compressive stress diagram can be seen in Figure 5 as shown; this building base compressive stress diagram should be the quasi-permanent combination compressive stress, that is: 1 times the dead load + 0.5 times the live load, and the entire underground foundation range should be calculated as a whole at one time during calculation;

[0074] When calculating the building foundation exterior wall pressure, various actual situations such as earth pressure, water pressure, ground load, and civil air defense load should be comprehensively considered. Specifically, it can be seen in Figure 6 as shown.

[0075] In the above step S2, the building foundation vibration isolation pads are divided into a foundation bottom elastic pad (hereinafter referred to as the bottom pad) and an underground foundation exterior wall elastic pad (hereinafter referred to as the side pad). The main function of the bottom pad is to reduce the vertical stiffness of the building foundation bottom and realize the regulation of the vertical natural frequency of the "building - elastic pad" system; the side pad mainly relies on the shear deformation ability of the material itself to reduce the restraint of the surrounding rock and soil of the underground foundation on the building structure and ensure the vertical free state of the building structure.

[0076] In the embodiment of the present invention, according to the obtained building base compressive stress diagram and building lateral pressure diagram above, and based on the deformation rate of the vibration isolation pad material under the corresponding pressure, the models and mechanical parameters of the building bottom pad and the building side pad are respectively determined; specifically:

[0077] According to the different building foundation compressive stresses, the building base compressive stress diagram is divided into multiple base areas, and based on the deformation rate of the vibration isolation pad material under the building foundation compressive stress, different models and mechanical parameters of the building bottom pad are adapted and fixed in different base areas;

[0078] According to the different building foundation exterior wall pressures, the building lateral pressure diagram is divided into multiple lateral areas, and based on the deformation rate of the vibration isolation pad material under the building foundation exterior wall pressure, different models and mechanical parameters of the building side pad are adapted and fixed in different lateral areas; based on this, in the embodiment of the present invention, the material model design is carried out according to the deformation rate of the elastomer material under the working pressure, and the material selection adapted to different areas can effectively improve the vibration isolation effect.

[0079] In addition, in the embodiments of the present invention, the building bottom pad and the building side pad are made of elastomeric materials such as polyurethane or rubber; under the corresponding pressure, the material deformation rate of the building bottom pad and the building side pad should be within the range of 7% to 20% (the applicable deformation range can be appropriately adjusted according to the mechanical properties of different materials); the optimal working deformation amount of the material is 10%. The greater the pressure difference range, the more types of elastic materials are used, and the uniform consistency of the deformation rate of the bottom pad material is ensured as much as possible.

[0080] In the above step S3, according to the distribution of the building foundation compressive stress and the geometric dimensions of the building bottom pad, the building foundation is divided into multiple foundation grid units, and each foundation grid unit corresponds to a piece of building bottom pad. Specifically, reference can be made to Figure 7; where Figure 7(a) is the quasi-permanent combined compressive stress diagram of the foundation; Figure 7(b) is the corresponding paving grid diagram of the bottom pad, and different colors represent different material models; if the whole elastic pad cannot meet the stress design requirements, local cutting can be carried out; finally, the paving diagram of the elastic pad at the bottom of the foundation is drawn.

[0081] In the above step S4, according to the distribution of the building foundation exterior wall pressure and the geometric dimensions of the building side pad, the building foundation exterior wall is divided into multiple lateral grid units, and each lateral grid unit corresponds to a piece of building side pad; different types of elastic materials are laid on the building side pad according to the lateral pressure; finally, the paving diagram of the elastic pad on the building foundation exterior wall is drawn.

[0082] In the above step S5, paving is carried out according to the paving diagram of the elastic pad at the bottom of the foundation and the paving diagram of the elastic pad on the building foundation exterior wall to achieve building vibration isolation.

[0083] The above embodiments of the present invention provide a refined design method and process for the building foundation vibration isolation pad, and stipulate the material selection basis and principles for the building foundation vibration isolation pad, which can make the vibration isolation pad more adaptable to the upper vibration isolation building and achieve better vibration isolation effects.

[0084] In the above step S6, based on the building foundation compressive stress and the paving diagram of the elastic pad at the bottom of the foundation, combined with the dynamic elastic modulus, paving area and thickness of the building bottom pad, the equivalent stiffness and equivalent mass of the building bottom pad are calculated; assuming that the building foundation is divided into n foundation grid units, then:

[0085] (1) The equivalent stiffness of the building bottom pad is expressed as:

[0086]

[0087] (2) The equivalent mass of the building bottom pad is expressed as:

[0088]

[0089] Where, k eqdenotes the equivalent stiffness of the building base mat; n denotes that a total of n base grid units are divided, that is, a total of n building base mats are required; A i denotes the area of the building base mat laid on the i-th base grid unit; E i denotes the dynamic elastic modulus of the building base mat laid on the i-th base grid unit; h denotes the thickness of the building base mat; m eq denotes the equivalent mass of the building base mat; σ i denotes the quasi-permanent combination compressive stress corresponding to the i-th base grid unit; g denotes the acceleration due to gravity.

[0090] In the above step S7, according to the equivalent stiffness and equivalent mass, the vertical natural frequency of the vibration-isolated building is obtained; the theoretical vertical natural frequency f0 of the vibration-isolated building is expressed as:

[0091]

[0092] In the above step S8, groundwater has an adverse effect on the vibration isolation performance of the base mat, mainly including two aspects. On the one hand, groundwater will change the mechanical properties of materials. Elastic pads are mostly microporous materials. Once the internal cavities of the materials are flooded, the dynamic elastic modulus of the materials will increase. On the other hand, when the groundwater level is higher than the elevation of the building foundation bottom surface, under the action of groundwater buoyancy, the equivalent load mass above the elastic pad will be reduced. Therefore, for the working conditions with a relatively high groundwater level and possible immersion of the elastic pad material, the influence of groundwater should be considered. The vertical natural frequency of the vibration-isolated building is corrected according to the influence of groundwater; the corrected vertical natural frequency of the vibration-isolated building is expressed as:

[0093]

[0094] where, f 水，0 denotes the theoretical vertical natural frequency of the vibration-isolated building corrected according to the influence of groundwater; E 水，i denotes the dynamic elastic modulus of the elastic pad material in the saturated state of water immersion; ρ 水 denotes the density of groundwater; H denotes the height difference between the groundwater level and the building raft foundation bottom.

[0095] In the above step S9, it can be seen from the above vertical natural frequency formula of the vibration-isolated building that when other conditions remain unchanged, the vertical natural frequency of the vibration-isolated building is inversely proportional to the square root of the thickness h of the building base mat. The vertical natural frequency of the vibration-isolated building can be regulated by the thickness h of the building base mat. The thicker the vibration isolation pad, the lower the vertical natural frequency of the vibration-isolated building; considering the vibration isolation effect, economy and the influence on the stability and safety of the building structure of the base mat comprehensively, the value range of the base mat thickness is usually 25mm ≤ h ≤ 75mm. Figure 8 gives the corresponding curve of the vertical natural frequency of the vibration-isolated building and the thickness h of the building base mat, from Figure 8It can be seen that if the thickness of the bottom pad is increased from 25 mm to 50 mm, the vertical natural frequency of the vibration isolation building can be reduced to 0.7 times, and when the thickness is increased from 25 mm to 75 mm, the vertical natural frequency of the vibration isolation building can be reduced to 0.58 times.

[0096] Based on the corrected vertical natural frequency of the vibration isolation building, the vibration transfer ratio of the vibration isolation building corresponding to different vibration source excitation frequencies can be obtained from the vibration transfer ratio formula provided in the background technology at the vertical natural frequency of the vibration isolation building; finally, based on the vibration transfer ratio, the vibration reduction amount of the vibration isolation building for different vibration source excitation frequencies is obtained; this vibration reduction amount can be expressed as:

[0097] VL j =20log(η j )

[0098] where VL j represents the vibration reduction amount of the vibration isolation building for the jth vibration source excitation frequency; η j represents the vibration transfer ratio of the vibration isolation building for the jth vibration source excitation frequency.

[0099] Figure 9 The vibration reduction amounts of buildings with vibration isolation pads of different thicknesses for subway excitation loads of different frequencies are given (in the figure, the natural frequency of the 25-mm thick elastic pad is assumed to be 15 Hz and the damping ratio is 0.05). From Figure 9 it can be clearly determined the vibration isolation effect of the designed elastic pad on subway vibrations of different frequencies. Increasing the thickness of the elastic pad can increase the range of the vibration isolation area and improve the vibration reduction effect. Therefore, for the excessive amount of subway vibration, the vibration isolation pad can be refined designed based on the design method of the present invention.

[0100] In summary, a building vibration isolation method for environmental vibration control provided by an embodiment of the present invention can be used for the refined design and effect evaluation method of the building foundation vibration isolation pad for environmental vertical vibration control. Aiming at the complex actual working conditions such as uneven foundation pressure, groundwater, and foundation lateral pressure constraints of the shared underground foundation building complex, the selection design method, principles, and basis of the vibration isolation pad are given, and the refined regulation design and evaluation method of the vertical natural frequency of the vibration isolation building are proposed. The present invention can provide theoretical and technical guidance for the design and effect evaluation of the building foundation vibration isolation pad, and determine a more economical and effective building vibration isolation control scheme.

[0101] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other.

[0102] The foregoing description of the disclosed embodiments enables those skilled in the art to practice or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A building vibration isolation method for environmental vibration control, characterized in that: The steps include: Obtain the building foundation compressive stress and the building foundation external wall pressure, and construct the corresponding building base compressive stress diagram and building lateral pressure diagram; According to the building base compressive stress diagram and the building lateral pressure diagram, and based on the deformation rate of the vibration isolation pad material under the corresponding pressure, the model and mechanical parameters of the building base pad and the building side pad are determined respectively; According to the distribution of the compressive stress of the building foundation and the geometric dimensions of the building base pad, the building base is divided into a plurality of base grid units, each base grid unit corresponds to a piece of the building base pad, and a foundation base elastic pad paving diagram is drawn; According to the distribution of the pressure on the building foundation outer wall and the geometric dimensions of the building side pad, the building foundation outer wall is divided into a plurality of lateral grid units, each lateral grid unit corresponds to a piece of building side pad, and a foundation outer wall elastic pad paving diagram is drawn; Paving is performed according to the foundation bottom elastic pad paving diagram and the foundation outer wall elastic pad paving diagram to achieve building vibration isolation; The following steps are also included: Based on the compressive stress of the building foundation and the paving diagram of the elastic pad at the bottom of the foundation, combined with the dynamic elastic modulus, paving area and thickness of the building base pad, the equivalent stiffness and equivalent mass of the building base pad are calculated; According to the equivalent stiffness and equivalent mass, the vertical natural frequency of the vibration isolation building is obtained; According to the influence of groundwater, the vertical natural frequency of the vibration isolation building is corrected; Based on the corrected vertical natural frequency of the vibration isolation building, the vibration transmissibility of the vibration isolation building corresponding to different vibration source excitation frequencies is obtained; Based on the vibration transmissibility, the vibration reduction amount of the vibration isolation building to different vibration source excitation frequencies is calculated; The corrected vertical natural frequency of the vibration isolation building is expressed as: Among them, f 水，0 It represents the theoretical vertical natural frequency of the vibration isolation building after correction according to the influence of groundwater; E 水，i Represents the dynamic elastic modulus of the elastic pad material in the water-saturated state; ρ 水 represents the groundwater density; H represents the height difference between the groundwater level and the base of the building raft; k eq A represents the equivalent stiffness of the building base pad; n means that a total of n base grid units are divided, that is, a total of n building base pads are required; i represents the area of ​​the building base pad laid by the i-th base grid unit; h represents the thickness of the building base pad; m eq Represents the equivalent mass of the building base; σ i represents the quasi-permanent combined compressive stress corresponding to the i-th base grid unit; g represents the gravitational acceleration.

2. A building vibration isolation method for environmental vibration control according to claim 1, characterized in that: The pressure of the building foundation outer wall is obtained by combining the soil pressure, water pressure, ground load and civil air defense load of the building foundation outer wall.

3. A building vibration isolation method for environmental vibration control according to claim 1, characterized in that: The building bottom pad and the building side pad are made of polyurethane or rubber elastic materials.

4. A building vibration isolation method for environmental vibration control according to claim 1, characterized in that: According to the building base compressive stress diagram and the building lateral pressure diagram, and based on the deformation rate of the vibration isolation pad material under the corresponding pressure, the model and mechanical parameters of the building base pad and the building side pad are determined respectively; Specifically include: According to the different compressive stresses of the building foundation, the building base compressive stress diagram is divided into multiple base areas, and based on the deformation rate of the vibration isolation pad material under the compressive stress of the building foundation, building base pads of different models and mechanical parameters are adapted and fixed in different base areas; According to the different pressures on the building foundation outer wall, the building lateral pressure diagram is divided into multiple lateral areas. Based on the deformation rate of the vibration isolation pad material under the pressure of the building foundation outer wall, building side pads of different models and mechanical parameters are adapted and fixed in different lateral areas.

5. A building vibration isolation method for environmental vibration control according to claim 4, characterized in that: The deformation rate of the building bottom pad and the building side pad should be in the range of 7% to 20%, and the optimal working deformation is 10%.

6. The building vibration isolation method for environmental vibration control according to claim 1, characterized in that: (1) The equivalent stiffness of the building base is expressed as: (2) The equivalent mass of the building base is expressed as: (3) The theoretical vertical natural frequency of the vibration isolation building is expressed as: Among them, E i represents the dynamic elastic modulus of the building base pad laid by the i-th base grid unit; f0 represents the theoretical vertical natural frequency of the vibration isolation building.

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