JP7590908B2 - Floor vibration analysis system - Google Patents

Description

The present invention relates to a floor vibration analysis system that analyzes floor vibrations.

Conventionally, floor vibration analysis systems have been proposed that predict vibrations when an external force is applied to a floor. For example, Patent Document 1 proposes a system that predicts floor vibrations using vibration analysis techniques such as the Rayleigh-Ritz method from input data such as various types of data, including building outline data, street data, beam data, wall data, floor data, and column data.

JP 2017-182408 A

However, when predicting floor vibrations with the system of Patent Document 1, various data must be input, including not only the dimensions of each component, but also the physical properties of the materials that make them up, and the analysis takes an enormous amount of time. Furthermore, because floor vibration analysis is a dynamic analysis, it often does not match the results of actual measurements. In addition, partition walls, which are non-structural parts (secondary components) that do not form part of the building's framework, are not reflected in the floor vibration analysis, but in reality, the results of actually measured vibrations can vary greatly depending on whether or not there are partition walls, and the presence or absence of partition walls.

The present invention was made in consideration of these points, and its purpose is to provide a floor vibration analysis system that can analyze the floor vibration of a building, taking into account the effects of partition walls, with simpler input conditions.

The floor vibration analysis system according to the present invention is a floor vibration analysis system that analyzes the vibration of a vibration evaluation point present in an evaluation area having a rectangular shape in plan view, the evaluation area including a beam structure in which small beams are arranged in a space surrounded by the main beams of a steel-framed building, and a rectangular floor slab supported by the beam structure. The floor vibration analysis system calculates the vertical acceleration of the time-varying vibration evaluation point when a time-varying excitation force acts as an external force at the vibration evaluation point of the evaluation area where a partition wall is arranged, and calculates the vertical acceleration of the time-varying vibration evaluation point from the weight of the floor slab of the evaluation area acting on the beam structure. The system is characterized by having a mass calculation unit that calculates the mass at the floor slab and the beam structure, a spring constant calculation unit that calculates the natural frequency of the floor in the evaluation area from the beam structure information and the floor slab information, and calculates the spring constant at the vibration of the vibration evaluation point based on the natural frequency, a damping constant calculation unit that calculates the damping constant at the vibration of the vibration evaluation point from at least the partition wall structure information, and an acceleration calculation unit that calculates the acceleration of the vibration evaluation point with time change as the vibration of a one-degree-of-freedom system of the floor slab and the beam structure based on the time-varying excitation force, the spring constant, the mass, and the damping constant.

The inventors found that when analyzing floor vibration, the analysis results differ depending on whether or not a partition wall is present. Furthermore, in the course of their investigation and study, they found that partition walls have a high contribution rate to attenuation of floor vibration. Until now, structures such as columns and exterior walls have also been taken into consideration in floor vibration analysis, but according to the present invention, it is possible to perform vibration analysis of vibration evaluation points in the vibration of a one-degree-of-freedom system of the floor slab and beam structure as a simple model of a spring-mass-damper system in which the floor slab and beam structure are springs, the weight of the floor slab is a mass point, and partition walls, etc. are dampers. This makes it easy to grasp the effect of floor vibration caused by partition walls.

In a more preferred embodiment, the information about the partition wall is the length of the partition wall and the distance from the vibration evaluation point to the partition wall, and the damping constant calculation unit calculates the damping constant based on at least the length of the partition wall and the distance from the vibration evaluation point to the partition wall.

According to this aspect, since the vibration damping characteristics of the vibration evaluation point are highly dependent on the length of the partition wall and the distance to the vibration evaluation point, it is possible to more accurately analyze floor vibration by calculating the damping constant from a multiple regression equation or correspondence table based on these values.

In a more preferred embodiment, there are multiple partition walls, the partition wall information includes the length of each partition wall, the distance from the vibration evaluation point to each partition wall, and the arrangement of the multiple partition walls, and the damping constant calculation unit calculates the damping constant based on at least the length of each partition wall and the distance from the vibration evaluation point to each partition wall, and corrects the damping constant with a numerical value corresponding to the arrangement of the multiple partition walls.

Here, since the vibration damping characteristics of the vibration evaluation point depend greatly on the length of the partition wall and the distance to the vibration evaluation point, floor vibration can be analyzed more accurately by calculating the damping characteristics from data including a multiple regression equation based on these values and a correspondence table that associates the parameters of the partition wall with damping constants. In particular, when there are multiple partition walls, the layout of the partition walls greatly contributes to the damping characteristics, so floor vibration can be analyzed more accurately by making corrections using correction coefficients that correspond to these layouts. The length and layout of the partition walls can be optimized.

In a more preferred embodiment, the floor vibration analysis system includes an analysis unit that calculates the acceleration for each vibration frequency by performing frequency response analysis on the acceleration waveform of the vibration evaluation point calculated by the acceleration calculation unit. According to this embodiment, the analysis unit can calculate the perception probability of vibration by analyzing the acceleration waveform.

In a more preferred embodiment, the building has a structure in which a vibration control device is placed on the floor slab, the evaluation area includes the vibration control device, and the acceleration calculation unit calculates the acceleration in vibration of a two-degree-of-freedom system consisting of the vibration control device, the floor slab, and the beam structure. According to this embodiment, the effect of floor vibration due to the presence or absence of a vibration control device can be confirmed by performing a vibration analysis of a one-degree-of-freedom system of the floor slab and beam structure when there is no vibration control device, and a vibration analysis of a two-degree-of-freedom system of the vibration control device, the floor slab, and the beam structure when there is a vibration control device.

According to the present invention, it is possible to predict floor vibrations of a target building, taking into account the effects of partition walls, with simpler input conditions.

1 is a diagram showing the configuration of a floor vibration analysis system according to the present invention; FIG. 2 is a block diagram of the arithmetic unit shown in FIG. 1 . 2 is an example of an analysis model performed by the floor vibration analysis system shown in FIG. 1 . 3A is a schematic diagram for explaining the effective width of the floor slab of the spring constant calculation section shown in FIG. 2, and FIG. 3B is a schematic diagram for explaining the calculation of the second moment of area of the entire floor constituting the evaluation area. 13(a) and (b) are examples of analytical models for explaining the arrangement of multiple partition walls. 3 is a vibration model of a one-degree-of-freedom system of a vibration equation for explaining the calculation of acceleration by the acceleration calculation unit shown in FIG. 2 . 4A is the waveform of the excitation force at the evaluation point, and FIG. 4B is the waveform of the acceleration at the evaluation point. 3 is a graph showing the results of calculation of acceleration for each vibration frequency by the analysis unit shown in FIG. 2 . 3 is a vibration model of a two-degree-of-freedom system of a vibration equation for explaining calculation of acceleration by the acceleration calculation unit shown in FIG. 2 according to a modified example.

The floor vibration analysis system 1 according to this embodiment of the present invention will be described below with reference to the drawings.

First Embodiment
1. Device configuration of floor vibration analysis system 1 As shown in Fig. 1, the floor vibration analysis system 1 according to this embodiment analyzes floor vibration at a vibration evaluation point on a floor of a target building. The floor vibration analysis system 1 will be described below. Note that the vibration evaluation point is a point on a floor slab where floor vibration is to be evaluated, and even if a vibration control device (described later) is provided on the floor slab, it is also a point on the floor slab. In this embodiment, the structural type of the building where floor vibration analysis is performed is a steel frame structure.

In this embodiment, the model to be analyzed is a model for floor analysis of vibrations at a vibration evaluation point C that exists in an evaluation area 56 that is rectangular in plan view, and includes a beam structure 55 in which minor beams 54 are arranged in a space surrounded by major beams 52 of a steel-framed building 5 as shown in Figure 3, and a rectangular floor slab 51 supported by the beam structure 55.

Here, the vibration evaluation point C is the center of the evaluation area 56 in a plan view. The main beams 52 include a main beam 52 aligned along the first direction L1 and a main beam 52 aligned along the second direction A2 perpendicular to the first direction A1. The periphery of the rectangular evaluation area 56 is composed of edges along the first direction A1 and the second direction A2. In this embodiment, three small beams 54 are provided, and each small beam 54 is disposed between the main beams 52, 52 along the second direction A2, and the three small beams 54 are provided at equal intervals in the first direction A1.

In plan view, the evaluation area 56 is a rectangular evaluation area consisting of a long side of length L1 and a short side of length L2. Columns 57 are provided at the four corners of the evaluation area 56, but in this embodiment, the analysis is performed without taking the columns 57 into consideration. Note that if a vibration control device is provided on the floor slab 51, this evaluation area 56 also includes the vibration control device. In this embodiment, a partition wall 60A is provided on the floor slab 51.

The floor vibration analysis system 1 comprises at least an input device 2, a calculation device 3, and a display device 4. The input device 2 is a device such as a keyboard for inputting analysis conditions and the like to the calculation device 3. The calculation device 3 comprises a memory such as a RAM or ROM in which a floor vibration analysis program is recorded, and a CPU that executes the floor vibration analysis program. The display device 4 is a display that outputs the results calculated by the calculation device 3.

In this embodiment, the input device 2 and the display device 4 are provided separately, but for example, a touch panel display that integrates these functions may be provided. Also, the input device 2 and the display device 4 may be connected to the calculation device 3 via a network.

The calculation device 3 of the floor vibration analysis system 1 calculates the vertical acceleration A(t) of the time-varying vibration evaluation point C when a time-varying excitation force F(t) acts as an external force at the vibration evaluation point C of the evaluation area 56 where the partition wall 60A is located.

Specifically, to perform such calculations, as shown in FIG. 2, the calculation device 3 mainly comprises, as software, a mass calculation unit 31, a spring constant calculation unit 32, a damping constant calculation unit 33, an acceleration calculation unit 34, and an analysis unit 35.

2. Mass calculation unit 31 The mass in the vibration of vibration evaluation point C is calculated from the weight of floor slab 51 in evaluation area 56 acting on beam structure 55. For example, as shown in FIG. 4, the mass m of floor slab 51 acting on small beam 54 is about 0.25 to 0.3 times the total mass of floor slab 51, so a value in this range is multiplied by the total mass of floor slab 51 to calculate mass m. The mass m calculated by mass calculation unit 31 is input to acceleration calculation unit 34.

3. Regarding the spring constant calculation unit 32 The spring constant calculation unit 32 calculates the natural frequency ω in the evaluation area 56 surrounded by the girder 52 from the information on the beam structure 55 and the information on the floor slab 51, and calculates the spring constant k in the vibration of the vibration evaluation point C based on the natural frequency ω. Specifically, the spring constant k is calculated based on the effective mass m calculated by the mass calculation unit 31 below and the natural frequency (first-order natural frequency) ω, using the following formula (1).

The natural frequency ω shown in formula (1) can be calculated using formula (2) below. In formula (2), α is the support condition of the main beam 52 or sub-beam 54 (hereinafter referred to as "beam") being calculated. In the case of a simply supported beam, α = 1, and in the case of a fixed supported beam, α = 1.5 is used.

L is the length of the beam to be calculated, and E is the Young's modulus of that beam. I is the second moment of area including the beam and the floor slab 51 it supports (effective equivalent second moment of area of a completely composite beam). ρ is the mass per unit length of the beam. Therefore, the natural frequencies ω of the main girder 52 and the secondary beam 54 are calculated, and the smallest natural frequency ω among these is regarded as the natural frequency of the floor within the evaluation area 56 surrounded by the main girder 52 (the primary natural frequency of the entire span).

Here, the effective equivalent moment of inertia I of the complete composite beam shown in formula (2) can be calculated using formula (3) shown below. In formula (3), B is the effective width of the floor slab 51 (see FIG. 4(a)), t is the thickness of the floor slab 51, _Xn is the length from the surface of the floor slab 51 to the neutral axis, I _s is the moment of inertia of the beam (girder 52 or sub-girder 54) to be calculated, and A _s is the cross section of the beam (girder 52 or sub-girder 54). In FIG. 4(a), the girder 52 and sub-girder 54, which are H-shaped steel, are drawn to have the same size for the sake of convenience, but in reality, their sizes are different.

Furthermore, _ds in formula (3) is the length from the surface of the floor slab 51 to the center of gravity of the beam (main beam 52 or sub-beam 54). In floor slabs using deck plates, the thickness of the flat concrete on the top of the deck plate is regarded as the effective thickness of the floor slab, and this length is, for example, 80 mm or more.

Here, the effective width B of the floor slab 51 used in calculating the elastic rigidity of the composite beam is the width b of the upper flange of the beam plus the effective width b _a of the floor slab on both sides or one side of the upper flange, as shown in Figure 4 (a).

The floor slab joint width b _a can be calculated using one of the following formulas (4-1) to (4-4). Formulas (4-1) and (4-2) are used in the case of fixed support beams (i.e. rigid frame members and continuous beams), while formulas (4-3) and (4-4) are used in the case of simply supported beams.

Here, a is the distance from the end of the steel frame top flange to the end of the adjacent top flange in the case of parallel beams, as shown in Figure 4(a), and in the case of a single T-beam or a beam consisting of a cantilever slab, it is twice the distance from the end of the top flange on one side to the end of the floor slab. l is the span length of the fixed support beam, and l ₀ is the span length of the simply supported beam.

Here, _xn and _ds - _xn can be calculated by the following formulas (5) and (6). Note that the neutral axis is outside the floor slab. Here, in formula (5), _t1 is t/ _ds , _Pt is As _/ (B· _ds ), and n is the Young's modulus ratio, which is 15.

Although the natural frequency ω was calculated using the above formulas (2) to (6), for example, when the number of small beams arranged in parallel in the same direction is two or less, the following formula (7) may be used, where _Ln is the length of the evaluation area 56 (orthogonal slab) in the direction perpendicular to the beam to be calculated.

In this way, the spring constant calculation unit 32 can calculate the spring constant k by inputting information on the beam structure 55 required for calculation using the above formula, including the size of the main girder 52 (specifically, length, beam width, beam depth, etc.), the size of the secondary beams 54 (specifically, length, beam width, beam depth, etc.), and the number of secondary beams 54, as well as information on the floor slab 51, including the mass, thickness, and, if necessary, specifications of the floor slab 51. Note that the number of secondary beams 54 can be used simply when calculating the distance a from the end of the steel frame upper flange to the end of the upper flange of the adjacent beam in parallel beams, as shown in Figure 4(a).

4. Regarding the damping constant calculation unit 33 The damping constant calculation unit 33 calculates the damping constant h in the vibration of the vibration evaluation point C from at least the information of the partition wall 60A. When calculating the damping constant h, information on the length of the main girder 52 (i.e., the span) may be further used. In this embodiment, it is preferable that the damping coefficient h is calculated by further adding information on the partition wall 60A to the floor slab 51 and the beam structure 55. That is, it is preferable that the calculated damping coefficient h is calculated from the influence of the damping characteristics of the partition wall 60A and the damping characteristics of the floor slab 51 and the beam structure 55. In the case of vibration of a one-degree-of-freedom system, the acceleration calculation unit 34 described later calculates the damping coefficient c shown in Equation (8) described later from the calculated damping constant h.

Here, the information on the partition wall 60A is the length G1 of the partition wall 60A and the distance LG1 from the vibration evaluation point C to the partition wall 60A (for example, the center g1). Specifically, the damping constant calculation unit 33 calculates the damping constant h based on the length G1 of the partition wall 60A and the distance LG1 from the vibration evaluation point C to the partition wall 60A.

The inventor's research has revealed that the vibration damping characteristics of vibration evaluation point C are highly dependent on the length G1 of the partition wall 60A and the distance to the vibration evaluation point C. A multiple regression analysis is performed from the damping constant h measured in an actual building, the length G1, and the distance LG1, and the damping constant h can be calculated from a regression equation using these as variables or a correspondence table that associates the length G1 and the distance LG1 with the damping constant h. This allows floor vibration to be analyzed accurately. The above-mentioned span may be added as a variable to this regression equation or correspondence table. Furthermore, parameters such as the physical properties of the floor slab 51, the length of the short side or long side, the length of the main girder in the beam structure 55, or the span may be added as variables to these regression equations or correspondence tables.

Furthermore, as shown in Figures 5(a) and (b), when there are multiple partition walls such as partition walls 60A and 60B, the partition wall information includes the lengths G1 and G2 of each partition wall 60A and 60B, the distances LG1 and LG2 from the vibration evaluation point C to each partition wall 60A and 60B, and the arrangement of the multiple partition walls 60A and 60B. In Figure 5(a), the two partition walls 60A and 60B are arranged so as to be parallel, and in Figure 5(b), the two partition walls 60A and 60B are arranged so as to be perpendicular to each other.

The damping constant calculation unit 33 calculates the damping constant h based on the lengths G1, G2 of the partition walls 60A, 60B and the distances LG1, LG2 from the vibration evaluation point C to the partition walls 60A, 60B. Here, a multiple regression analysis is performed from the damping constant h measured in an actual building, the lengths G1, G2, and the distances LG1, LG2, and the damping constant h can be calculated from a multiple regression equation using these as variables or a correspondence table that associates the lengths G1, G2, the distances LG1, LG2, and the damping constant h. Note that in the multiple regression equation and the correspondence table, as shown above, the lengths G1, G2 may not be treated as individual variables, but the total length (sum value) of these may be used as a variable. Similarly, the total distance (sum value) of the distances LG1, LG2 may be used as a variable. Furthermore, as in the above case, parameters such as the physical properties of the floor slab 51, the length of the short or long sides, the length of the girder in the beam structure 55, or the span may be added as variables to these regression equations or correspondence tables.

As shown in Figures 5(a) and (b), if the arrangement of the partition walls 60A and 60B changes, the damping constant h also changes. Therefore, a numerical value corresponding to these arrangements may be set as a correction coefficient, and the damping constant h may be corrected by multiplying the calculated damping constant h by the correction coefficient. Note that this correction is not limited to the case where there are two partition walls, and may be set according to the number of partition walls and their arrangement.

As such, since the vibration damping characteristics of vibration evaluation point C are highly dependent on the length of partition walls 60A, 60B and the distance to vibration evaluation point C, floor vibration can be analyzed more accurately by calculating the damping constant h from data including a multiple regression equation based on these values and a correspondence table that associates the parameters of the partition walls with damping constants.

In particular, when there are multiple partition walls 60A, 60B, the arrangement of these partition walls 60A, 60B contributes greatly to the damping characteristics, so by making corrections using correction coefficients and the like associated with these arrangements, floor vibrations can be analyzed more accurately. This allows optimization of the lengths G1, G2 and arrangement (layout) of the partition walls 60A, 60B.

5. Acceleration Calculation Unit 34 Next, the acceleration calculation unit calculates the acceleration A(T) of the vibration evaluation point with time change as the vibration of the one-degree-of-freedom system of the floor slab 51 and the beam structure 55 based on the excitation force F(T) with time change, the spring constant k, the mass m, and the damping coefficient c (value calculated from the damping constant h). In the acceleration calculation unit 34, the damping coefficient c is a value calculated from the damping constant h calculated by the damping constant calculation unit 33. Specifically, a vibration model of the one-degree-of-freedom system as shown in FIG. 6 is assumed, and the vibration equation shown in Equation (8) is obtained. Here, T in parentheses is time, and (T) means that it is a function of time T.

The time-varying excitation force F(T) is a condition of the external force applied to the evaluation area 56 of the floor slab 51. For example, it is a numerical value that corresponds to the conditions when a certain number of people jump, walk, jog, perform heel strikes, aerobic bending and stretching, etc. in the evaluation area 56.

As described above, A(T) is the acceleration of the vibration evaluation point that changes with time, V(T) is the velocity of the vibration evaluation point C that changes with time, and X(T) is the displacement of the vibration evaluation point C that changes with time. Note that if the displacement X(T) is differentiated with respect to time, it becomes the velocity V(T), and if the velocity V(T) is differentiated with respect to time, it becomes the acceleration A(T).

Based on the differential equation of formula (8), the acceleration A(T) of the vibration evaluation point C, which changes over time, can be calculated by numerical calculation. For example, the acceleration A(T) can be calculated by commonly known methods such as the average acceleration method, the linear acceleration method, the Newmark β method, the Wilson θ method, and the Runge-Kutta method.

Here, to briefly explain the Newmark β method, the excitation force F(T) to be analyzed is prepared as a waveform composed of numerical data for each time interval ΔT, and if the excitation force after m time intervals ΔT is defined as excitation force _Fm , the acceleration at that time is defined as _Am , the velocity is defined as _Vm , and the displacement is defined as _Xm , then the velocity after m+1 time intervals ΔT is defined as Vm ₊₁ and the displacement is defined as Xm ₊₁ can be assumed by the following formulas (9) and (10). Note that when β in formula (10) is 1/4, it is the average acceleration method, and when it is 1/6, it is the linear acceleration method. β can be set so as to obtain an analysis value of acceleration with higher accuracy by comparing it with the actual measured value of acceleration.

These equations (9) and (10) are substituted into equation (11), which is the vibration equation after a time interval ΔT equivalent to m+1 times of equation (8).

When rearranged in terms of V _m+1 , the acceleration A _m+1 after the time interval ΔT for m+1 times has elapsed can be calculated using the previously calculated spring constant k, mass m, and the excitation force F _m , acceleration A _m , velocity V _m , and displacement X _m for the previous M times. In this way, the acceleration for each ΔT can be calculated.

In this way, the waveform of the acceleration, which also changes with time, shown in Figure 7(b) can be calculated from the waveform of the excitation force, which also changes with time, shown in Figure 7(a).

6. Analysis Unit 35 The analysis unit 35 calculates the acceleration for each vibration frequency by performing frequency response analysis (by FFT) on the waveform of the acceleration A(T) of the vibration evaluation point C calculated by the acceleration calculation unit 34. This makes it possible to obtain a graph of the vibration perception probability (specifically, a graph without a vibration control device) showing the results of calculating the acceleration for each vibration frequency, as shown in FIG.

According to this embodiment, vibration analysis of vibration evaluation point C can be performed as the vibration of a simple model of a spring-mass-damper system in which the floor slab 51 and beam structure 55 are springs, the weight of the floor slab 51 is a mass point, and the partition wall 60A (60A, 60B) is a damper. This makes it easy to grasp the effect of floor vibration caused by the partition wall 60A (60A, 60B).

For example, as a modified example, the building has a structure in which a vibration control device 80 is placed on the floor slab 51, and the evaluation area 56 includes the vibration control device. The acceleration calculation unit 34 calculates the acceleration A(T) in the vibration of the two-degree-of-freedom system consisting of the vibration control device 80, the floor slab 51, and the beam structure 55.

In this case, the model shown in FIG. 9 can be assumed, where the mass of the floor slab 51 is m1, the spring constant is k1, and the damping constant is h1. These values can be calculated from the information of the beam structure 55 and the information of the floor slab 51 using the method described above. Furthermore, the mass of the vibration control device 80 is m2, the spring constant is k2, and the damping constant is h2, and these values are predetermined values specific to the device. Note that, since floor vibration analysis is performed with the vibration control device 80, an excitation force F(t) is applied to the floor slab 51, and floor vibration with the vibration control device 80 is evaluated from the acceleration A(T) at the vibration evaluation point C of the floor slab 51, just as in the case without the vibration control device 80 shown above.

Specifically, from the vibration model of the two-degree-of-freedom system shown in FIG. 9, a vibration equation similar to that of Equation (8) is created using the mass matrix m, damping matrix c, and spring constant matrix k (stiffness matrix) consisting of the masses m1 and m2, damping constants h1 and h2, and spring constants k1 and k2, and the acceleration A(T) of the vibration evaluation point C is calculated in the acceleration calculation unit 34 in the same manner as described above, and the acceleration for each vibration frequency is calculated in the analysis unit 35. For example, the damping matrix c is calculated from the damping constants h1 and h2 of the vibration system of the floor slab 51 and the beam structure 55 and the vibration system of the vibration damping device 80. As a result, by performing a vibration analysis of the one-degree-of-freedom system of the floor slab 51 and the beam structure 55 when the vibration damping device 80 is not present, and a vibration analysis of the two-degree-of-freedom system of the vibration damping device 80, the floor slab 51, and the beam structure 55 when the vibration damping device 80 is present, the influence of floor vibration due to the presence or absence of the vibration damping device 80 can be confirmed as shown in FIG. 8.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-mentioned embodiments, and various design changes can be made without departing from the spirit of the present invention as described in the claims.

1: Floor vibration analysis system, 31: Mass calculation section, 32: Spring constant calculation section, 33: Damping constant calculation section, 34: Acceleration calculation section, 35: Analysis section, 51: Floor slab, 52: Main beam, 54: Small beam, 55: Beam structure, 56: Evaluation area, 60A, 60B: Partition wall, C: Vibration evaluation point

Claims (5)

A floor vibration analysis system for analyzing vibrations of vibration evaluation points in an evaluation area having a rectangular shape in a plan view, the evaluation area including a beam structure in which a small beam is arranged in a space surrounded by a large beam of a steel-framed building and a rectangular floor slab supported by the beam structure,
the floor vibration analysis system calculates an upward and downward acceleration of the time-varying vibration evaluation point when a time-varying excitation force acts as an external force at the vibration evaluation point of the evaluation area where a partition wall is arranged,
A mass calculation unit that calculates a mass in vibration at the vibration evaluation point from the weight of the floor slab in the evaluation area acting on the beam structure;
A spring constant calculation unit that calculates a natural frequency of the floor in the evaluation area from the beam structure information and the floor slab information, and calculates a spring constant in vibration of the vibration evaluation point based on the natural frequency;
a damping constant calculation unit that calculates a damping constant for vibration at the vibration evaluation point from at least information on the partition wall;
and an acceleration calculation unit that calculates the acceleration of the vibration evaluation point, which changes over time, as a vibration of a one-degree-of-freedom system of the floor slab and the beam structure based on the time-varying excitation force, the spring constant, the mass, and the damping constant. The information on the partition wall includes a length of the partition wall and a distance from the vibration evaluation point to the partition wall,
2. The floor vibration analysis system according to claim 1, wherein the damping constant calculation unit calculates the damping constant based on at least a length of the partition wall and a distance from the vibration evaluation point to the partition wall. The partition wall is provided in a plurality of locations.
The partition wall information includes a length of each of the partition walls, a distance from the vibration evaluation point to each of the partition walls, and an arrangement state of the plurality of partition walls;
The floor vibration analysis system of claim 1, characterized in that the damping constant calculation unit calculates the damping constant based on at least the length of each partition wall and the distance from the vibration evaluation point to each partition wall, and corrects the damping constant with a numerical value corresponding to the arrangement state of the multiple partition walls. The floor vibration analysis system according to any one of claims 1 to 3, characterized in that the floor vibration analysis system includes an analysis unit that calculates the acceleration for each vibration frequency by performing frequency response analysis on the acceleration waveform of the vibration evaluation point calculated by the acceleration calculation unit. The building has a structure in which a vibration control device is arranged on the floor slab, and the evaluation area includes the vibration control device,
A floor vibration analysis system according to any one of claims 1 to 4, characterized in that the acceleration calculation unit calculates the acceleration in vibration of a two-degree-of-freedom system consisting of the vibration control device, the floor slab and the beam structure.

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