JP5376702B2 - RC member damage level evaluation method and system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently evaluate a level of damage without visual observation of a column. <P>SOLUTION: A system 1 for evaluating the level of damage includes peak sensors 2a, 2b and 2c, and a computation section 3 which performs the computation of measurement data from the peak sensors. The computation section 3 includes: a member angle computing section 6 which determines a maximum response member angle &theta; from the measurement data from the peak sensors; a conversion section 7 which converts the maximum response member angle to an elastic response displacement &delta; using elastoplastic characteristics including an equivalent natural period T<SB>eq</SB>of a rigid frame viaduct 4; a response characteristic computing section 8 which determines the elastic response characteristics of a structure group 21 using the equivalent natural period T<SB>eq</SB>and the elastic response displacement &delta;; an elastic response computing section 9 which computes the elastic response displacement by applying the equivalent natural period T<SB>eq</SB>of the rigid frame viaduct 4 as a non-measurement object to the elastic response characteristics of the structure group 21; and an inverse conversion section 10 which converts the elastic response displacement to the maximum response member angle. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a damage level evaluation method and system for RC members mainly applied to RC ramen viaducts for railways.

  Railroad viaduct substructures are often constructed as reinforced concrete ramen frames, but when designing and constructing them, it is necessary to fully study the seismic resistance of the viaduct and to conduct an appropriate earthquake damage survey after the disaster. It is also important to conduct the survey and feed back the survey results to the design and construction.

  On the other hand, the pillars that make up recent ramen frames are often reinforced with earthquake resistance by rolling up steel sheets based on the experience of damage caused by large earthquakes, making it difficult to conduct accurate seismic damage surveys visually. Yes.

  Under such circumstances, utilizing the fact that the relationship between the maximum response member angle generated at the column end and the damage level is generally grasped, the damage level of the column is quickly evaluated by measuring the maximum response member angle with a sensor. Possible damage level detection systems have been developed.

“Development of damage level detection system for RC RC ramen viaduct” (Annual Proceedings of Concrete Engineering, Vol.29, No.2, 2007)

  According to the above system, it is possible to evaluate the damage level of the column by installing a sensor on the column of the rigid frame and measuring the maximum response member angle of the column. Even in the case of a column that has been subjected to earthquake-proof reinforcement by rolling up a steel plate, it becomes possible to properly grasp the column damage.

  However, many viaducts for railroads are constructed by lining up a plurality of ramen viaducts in a row with predetermined intervals and bridging adjustment girders between them. Depending on the traffic conditions and ground properties, the structure shape such as length, width or height and the depth of the support base are different, and each ramen viaduct exhibits different behavior during earthquakes depending on the location.

  Therefore, in the above system, a sensor must be installed at least for each ramen viaduct, and the cost required for system construction becomes enormous, and development of a more rational system has been awaited.

  The present invention has been made in consideration of the above-described circumstances, and provides a damage level evaluation method and system for an RC member that can efficiently evaluate the damage level without the need to visually check a column. With the goal.

In order to achieve the above object, the damage level evaluation method for RC members according to the present invention includes an equivalent natural period for each bridge structure arranged in a row along the bridge axis direction as described in claim 1. While determining the elastoplastic characteristics, among the structure group consisting of each bridge structure, measure the maximum response member angle generated in the measurement object by a predetermined earthquake motion,
The maximum response member angle is converted into an elastic response displacement using the elastic-plastic characteristic of the measurement object, and the elasticity of the structure group with respect to the earthquake motion using a correspondence relationship with the equivalent natural period of the measurement object Find the response characteristics
The elastic response displacement of the non-measurement object is calculated by applying the equivalent natural period of the non-measurement object excluding the measurement object among the structure group to the elastic response characteristic of the structure group,

The elastic response displacement of the non-measurement object is converted into a maximum response member angle using the elastic-plastic characteristic of the non-measurement object,
The damage level of the non-measurement object is estimated from the maximum response member angle.

In addition, the RC member damage level evaluation system according to the present invention, as described in claim 2, is an object to be measured among a group of structures composed of bridge structures arranged in a line along the bridge axis direction. Measuring means for measuring the maximum response member angle generated in the measurement object by predetermined earthquake motion,
The maximum response member angle is converted into an elastic response displacement using an elasto-plastic characteristic including an equivalent natural period of the measurement object on which the measurement unit is installed, and a correspondence relationship with the equivalent natural period of the measurement object is Using an arithmetic processing unit for obtaining an elastic response characteristic of the structure group to the earthquake motion using,
The arithmetic processing unit calculates an elastic response displacement of the non-measurement object by applying an equivalent natural period of the non-measurement object excluding the measurement object to an elastic response characteristic of the structure group, and the elasticity By converting the response displacement into the maximum response member angle, the damage level of the non-measurement object can be estimated from the maximum response member angle.

  In the damage level evaluation method and system for RC members according to the present invention, all the maximum response member angles of each bridge structure are measured as in the past, or the measuring means for measuring the maximum response member angle is used for all bridge structures. Rather than installing the system, the structure group consisting of each bridge structure is divided into measurement objects and non-measurement objects, and then only the maximum response member angle of the measurement object is measured, or the maximum response member angle A measuring means for measuring is installed only on the measurement object.

  In this way, it is possible to reduce the cost related to measurement, but on the other hand, how to evaluate the damage level of a bridge structure that is not measured becomes a problem.

  The applicant assumes that the same seismic motion is input to a group of bridge structures arranged in a line along the bridge axis direction, while each bridge structure has an individual natural period. Therefore, based on the fact that the response to the above-mentioned ground motion varies from one bridge structure to another, the equivalent natural period in the group of structures is calculated using the maximum response member angle measured for the ground motion. Even if it is a non-measurement object that does not measure the maximum response member angle by creating the relationship with the elastic response displacement as an elastic response characteristic and applying the equivalent natural period of the non-measurement object to the elastic response characteristic We have obtained very useful knowledge that the level can be evaluated.

  That is, in the damage level evaluation method and system for RC members according to the present invention, first, elasto-plastic characteristics including an equivalent natural period are determined for each bridge structure arranged in a row along the bridge axis direction.

  Here, the bridge structure refers to a structural element composed of RC columnar members that support a vertical load acting on the bridge or a structural aggregate that includes the RC columnar members and vibrates as a whole, and the structural aggregate includes Includes bridges and girder bridges. Incidentally, when the structural aggregate is a ramen bridge, the structural element is a column, and when the structural aggregate is a girder bridge, the structural element is a pier. In addition, the structure aggregate widely includes those installed across rivers and those installed on land, and is not limited by location.

  On the other hand, a structure group consisting of each bridge structure is divided into a measurement object and a non-measurement object, and a measuring means for measuring the maximum response member angle is installed only on the measurement object.

  Although it may be determined by any standard whether each bridge structure belonging to the structure group is classified, as described later, the relationship between the equivalent natural period of the measurement object and the elastic response displacement is discrete. Therefore, the elastic response characteristics of the entire structure group are obtained from such a discrete relationship, so the static nonlinear analysis and the actual maximum response member angle for the bridge structure as the measurement object agree well. It is desirable that those equivalent natural periods are evenly distributed in a predetermined period range.

  Next, the maximum response member angle generated in the measurement object is measured by a measuring unit with respect to a predetermined earthquake motion.

  Next, the measured maximum response member angle is converted into an elastic response displacement using the elasto-plastic characteristics of the measurement object on which the measurement means is installed. The conversion from the maximum response member angle to the elastic response displacement is performed by, for example, converting the maximum response member angle into a plastic response displacement along the horizontal direction by using the result of static nonlinear analysis, and then converting the horizontal plastic displacement into Newmark's What is necessary is just to convert into elastic response displacement using a constant energy law.

  Next, the elastic response characteristic of the structure group with respect to the earthquake motion is obtained using the correspondence with the equivalent natural period of the measurement object. The relationship between the equivalent natural period and the elastic response displacement is measured or calculated by the number of measurement objects. For example, when the equivalent natural period is taken on the horizontal axis and the elastic response displacement is taken on the vertical axis, Since it is plotted discretely along the horizontal axis, if these discrete points are expanded to an arbitrary equivalent natural period by linear interpolation, for example, this becomes the elastic response characteristic of the structure group.

  Next, the elastic response displacement of the non-measurement object is calculated by applying the equivalent natural period of the non-measurement object to the above-described elastic response characteristics.

  Next, the elastic response displacement of the non-measurement object is converted into the maximum response member angle using the elastic-plastic characteristics of the non-measurement object. This conversion is the reverse of the above-described conversion operation. For example, first, the elastic response displacement is converted into a plastic response displacement using Newmark's constant energy law, and the plastic response displacement is then used as a result of static nonlinear analysis. Then, the maximum response member angle may be converted.

  If the maximum response member angle is found, it can be used to estimate the damage level of the non-measurement object.

  The damage level evaluation method and system for RC members according to the present invention measures the seismic motion itself when it is necessary to measure the maximum response member angle of the bridge structure when the bridge structure vibrates due to actual seismic motion. do not have to.

  This is because, even if the seismic motion is not measured, if the maximum response member angles of the measurement objects having different natural periods are measured as a result of receiving the seismic motion, the maximum response member angle for an arbitrary natural period, in other words, For example, it is based on the idea that the maximum response member angle of a non-measurement object can also be predicted.

  Embodiments of a damage level evaluation method and system for RC members according to the present invention will be described below with reference to the accompanying drawings. Note that components that are substantially the same as those of the prior art are assigned the same reference numerals, and descriptions thereof are omitted.

  FIG. 1 is a block diagram showing a damage level evaluation system for RC members according to this embodiment, and FIG. 2 is a side view of a structure group 21 to which the damage level evaluation system 1 is applied. As can be seen from these drawings, the RC member damage level evaluation system 1 according to this embodiment includes the ramen viaducts 4a, 4b, 4c as non-measurement objects as measurement objects arranged in a line along the bridge axis direction. This is applied to the column damage level evaluation of the structure group 21 composed of the ramen viaducts 4a 'and 4b' as the object, and the peak sensors 2a, 2b and 2c as the measuring means and the measurement data from the peak sensors And an arithmetic processing unit 3 for arithmetic processing.

  The peak sensors 2a, 2b, and 2c are installed on the ramen viaducts 4a, 4b, and 4c, respectively, and are orthogonal at the upper and lower ends generated in the columns 5a, 5b, and 5c of the ramen viaducts 4a, 4b, and 4c with respect to a predetermined earthquake motion. The maximum displacement amount on the positive and negative sides of the two horizontal components can be measured and stored.

  FIG. 3 is an installation diagram of the peak sensors 2a, 2b, and 2c, and FIG. 4 is an explanatory diagram illustrating a procedure for calculating the maximum response member angle θ using the peak sensors 2a, 2b, and 2c.

  As can be seen from these figures, when calculating the maximum response member angle θ, in order to avoid measurement errors when a plastic hinge is formed in the vicinity of the column head, under the beam near the column head of the ramen viaducts 4a, 4b, 4c. Is an upper measurement point 31 and a lower position about 1 m lower than the upper measurement point is a lower measurement point 32, and the upper and lower ends of the measurement rod 33 are respectively pin-joined to measure the angle of the measurement rod. .

Since the peak sensors 2a, 2b, and 2c measure the relative horizontal displacement w ₁ at a position separated from the upper measurement point 31 by the vertical distance H ₁ , the peak sensors 2a, 2b, and 2c are at the lower measurement point 32 that is separated from the upper measurement point 31 by the vertical distance H ₂ . The relative horizontal displacement w ₂ is

w ₂ = w ₁ (H ₂ / H ₁ )

The angle θ ′ of the measuring rod is

θ ′ = tan ⁻¹ (w ₂ / H ₂ )

Is required.

  On the other hand, the haunch portion 34 behaves as a rigid body, and the angle θ ′ of the measuring rod does not coincide with the maximum response member angle θ. Therefore, the maximum response member angle θ is converted by the following equation, where B is the height of the hunch 34.

θ = H ₂ / (H ₂ −B) · θ ′

The arithmetic processing unit 3 includes a member angle calculating unit 6 that obtains the maximum response member angles θa, θb, and θc from the measurement data from the peak sensors 2a, 2b, and 2c, and the maximum response member angle is determined by the ramen viaducts 4a, 4b, and 4c. Transformer 7 for converting to elastic response displacements δa, δb, δc using elastic-plastic characteristics including equivalent natural periods T _eq a, T _eq b, T _eq c, and equivalent natural periods T of ramen viaducts 4a, 4b, 4c a response characteristic calculation unit 8 for obtaining an elastic response characteristic of the structure group 21 with respect to the earthquake motion using a correspondence relationship between _eq a, T _eq b, T _eq c and elastic response displacements δa, δb, δc; 21, the equivalent natural periods T _eq a ′ and T _eq b ′ of the ramen viaducts 4 a ′ and 4 b ′ as non-measurement objects are used as the elastic response characteristics of the structure group 21 obtained by the response characteristic calculation unit 8. Apply ramen viaduct 4 An elastic response calculating section 9 for calculating elastic response displacements δa 'and δb' of '4b', and an inverse conversion section 10 for converting the elastic response displacements δa 'and δb' into maximum response member angles θa 'and θb', and Consists of.

  FIG. 5 is a flowchart showing a procedure for evaluating the column damage level of the structure group 21 using the RC member damage level evaluation system 1 according to the present embodiment. As shown in the figure, in order to evaluate the column damage level of the structure group 21 using the damage level evaluation system 1, first, a plurality of bridge structures belonging to the structure group 21 are set to have a maximum response member angle θ. Classification is made into a measurement object measured by the peak sensor 2 and a non-measurement object that is not measured (step 101).

  Here, although each bridge structure belonging to the structure group 21 vibrates with mutually different natural periods, each of the bridge structures is determined so as to be considered to vibrate integrally, and a plurality of ramen viaducts 4a, 4a ′, In the case of the structure group 21 constructed by connecting 4b, 4b 'and 4c with the adjustment girder 6 in a row along the bridge axis direction, each ramen viaduct is connected to the bridge structure in the present embodiment. Become.

Further, which of the bridge structures belonging to the structure group 21 is a measurement target and which is a non-measurement target is determined by the discrete of the equivalent natural period T _eq of the measurement target and the elastic response displacement δ. Since the elastic response characteristics of the entire structure group 21 are obtained from the relationship, the bridge structure to be measured is selected so that the static nonlinear analysis and the actual maximum response member angle are in good agreement In addition, it is desirable that the equivalent natural periods T _eq are distributed as evenly as possible within a predetermined period range.

  In the present embodiment, as described above, in the structure group 21, the ramen viaducts 4a, 4b, and 4c are classified as measurement objects, and the ramen viaducts 4a ′ and 4b ′ are classified as non-measurement objects.

Next, with respect to the structure group 21 composed of the ramen viaducts 4a, 4b, 4c and the ramen viaducts 4a ′, 4b ′, the equivalent natural periods T _eq a, T for each bridge structure, that is, for each of the ramen viaducts 4a, 4b, 4c Elasto-plastic characteristics including _eq b and T _eq c are determined, and elasto-plastic characteristics including equivalent natural periods T _eq a ', T _eq b' and T _eq c 'are determined for each of the ramen viaducts 4a' and 4b '. (Step 102).

In order to determine the equivalent natural period T _eq and the elasto-plastic characteristics including it, static nonlinear analysis may be performed on each ramen viaduct 4 and the results determined accordingly.

  FIG. 6 is an example showing an analysis model and its result for performing static nonlinear analysis on the ramen viaduct 4 and shows that the portion painted in gray is a rigid zone. As shown in the figure, in performing the static nonlinear analysis, the horizontal displacement and the seismic intensity are obtained for each node, and the response member angle of the column head is calculated. In this embodiment, the base plane located at a predetermined depth from the ground surface is used as a reference, and when calculating the response member angle, the horizontal displacement of the top of the structure is not simply divided by the column height. The value obtained by subtracting the horizontal displacement of the foundation from the horizontal displacement of the structure is divided by the column height.

Here, the relationship between horizontal displacement and seismic intensity at the top of the structure (node 0) is the elasto-plastic characteristics of each ramen viaduct 4. The secant rigidity connecting the yield point and the origin is the equivalent natural period T _eq . FIG. 7 is a graph showing the elastic-plastic characteristics obtained in this way.

  Next, the peak sensor 2a, 2b, the maximum displacement amount on the positive and negative sides of two orthogonal horizontal components at the upper and lower ends of the pillars 5a, 5b, 5c of the ramen viaducts 4a, 4b, 4c with respect to a predetermined earthquake motion. Measurement is performed at 2c (step 103).

  Next, the maximum response member angles θa, θb, θc are obtained by the member angle calculation unit 6 from the measurement data transmitted from the peak sensors 2a, 2b, 2c (step 104).

  Here, for the ramen viaducts 4a, 4b, 4c, the maximum response member angles θa, θb, θc are directly calculated from the measurement data of the peak sensors 2a, 2b, 2c. Good.

  Hereinafter, it becomes a step for performing damage evaluation of the ramen viaducts 4a ′ and 4b ′ which are non-measurement objects.

If the maximum response member angles θa, θb, and θc are calculated, these maximum response member angles are elastoplastic including the equivalent natural periods T _eq a, T _eq b, and T _eq c of the ramen viaducts 4a, 4b, and 4c. Using the characteristics, the conversion unit 7 converts the elastic response displacements δa, δb, and δc (step 105).

  In order to convert the maximum response member angles θa, θb, and θc into elastic response displacements δa, δb, and δc, first, using the results of static nonlinear analysis, the maximum response member angles θa, θb, and θc are used to determine the ramen viaducts 4a and 4b. , 4c at the top end, and the horizontal plastic displacement is converted into elastic response displacements δa, δb, δc using Newmark's constant energy law.

Next, using the corresponding relationship between the equivalent natural periods T _eq a, T _eq b, T _eq c of the ramen viaducts 4a, 4b, 4c and the elastic response displacements δa, δb, δc, An elastic response characteristic is obtained by the response characteristic calculation unit 8 (step 106).

FIG. 8 is a graph showing the elastic response characteristics of the structure group 21. As shown in the figure, in order to determine the elastic response characteristics of the structure group 21, the horizontal axis represents the equivalent natural period T _eq , the vertical axis represents the elastic response displacement δ, and the graph shows the equivalent natural period T _eq a , T _eq b, T _eq c and elastic response displacements δa, δb, δc may be plotted, and their discrete points (three points in this case) may be connected by, for example, a straight line.

In such a case, the equivalent natural period T _eq a, T _eq b, elastic response displacement corresponding to T _eq c other equivalent natural period T _eq is the elasticity of the equivalent natural period _{T eq a, T eq b,} T eq c The response displacements δa, δb, and δc are obtained by linear interpolation.

Next, among the structure group 21, the structure group obtained by the response characteristic calculation unit 8 using the equivalent natural periods T _eq a ′ and T _eq b ′ of the ramen viaducts 4 a ′ and 4 b ′ as non-measurement objects. By applying to the elastic response characteristic 21 (FIG. 8), the elastic response displacements δa ′ and δb ′ of the ramen viaducts 4a ′ and 4b ′ are obtained by the elastic response calculation unit 9 (step 107).

In obtaining the elastic response displacements δa ′ and δb ′, as shown in FIG. 9, the elastic response displacements δa ′ and δb ′ corresponding to the equivalent natural periods T _eq a ′ and T _eq b ′ are converted into the response characteristic calculation unit 8. What is necessary is just to obtain | require from the elastic response characteristic of the structure group 21 calculated | required by (4).

  Next, the elastic response displacements δa ′ and δb ′ are converted into the maximum response member angles θa ′ and θb ′ by the inverse conversion unit 10 (step 108).

  In obtaining the maximum response member angles θa ′ and θb ′, first, the elastic response displacements δa ′ and δb ′ are converted into plastic response displacements using the elastic-plastic characteristics of the ramen viaducts 4a ′ and 4b ′ and the constant energy of Newmark. Then, the maximum response member angles θa ′ and θb ′ may be obtained by converting each, and then applying the plastic response displacement to the static nonlinear analysis result.

  When the maximum response member angles θa ′ and θb ′ are obtained in this way, the column damage levels of the ramen viaducts 4a ′ and 4b ′ are evaluated using the known correspondence between the maximum response member angles and the damage levels. (Step 109).

As described above, according to the damage level evaluation system 1 and method for RC members according to the present embodiment, the maximum response member angles θa, θb, θc measured by the ramen viaducts 4a, 4b, 4c, which are measurement objects. Is used to create the elastic response characteristics of the structure group 21, and to the elastic response characteristics, the equivalent natural periods T _eq a 'and T _eq b' of the ramen viaducts 4a 'and 4b' that are non-measurement objects are applied. As a result, the maximum response member angles θa ′ and θb ′ can be appropriately estimated, and thus the damage level can be evaluated even for the ramen viaduct 4 that does not measure the maximum response member angle θ.

1 is a block diagram of a damage level evaluation system 1 according to the present embodiment. The side view of the structure group 21 to which the damage level evaluation system 1 is applied. Installation drawing of peak sensors 2a, 2b, 2c. Explanatory drawing which showed the procedure which calculates maximum response member angle | corner (theta) using the peak sensors 2a, 2b, 2c. The flowchart which showed the procedure which evaluates the column damage level of the structure group 21 using the damage level evaluation system 1. FIG. FIG. 3 is an explanatory diagram showing an analysis model for performing static nonlinear analysis on the ramen viaduct 4 and its result. A graph showing elastoplastic properties. The graph which showed the elastic response characteristic of the structure group. The graph which showed the procedure which calculates | requires the elastic response displacement of a non-measurement target object.

Explanation of symbols

1 RC member damage level evaluation system 2a, 2b, 2c Peak sensor (measuring means)
3 arithmetic processing units 4a, 4b, 4c Ramen viaduct (measurement object)
4a ', 4b' Ramen viaduct (non-measurement object)
5a, 5b, 5c pillar

Claims (2)

Determine the elasto-plastic characteristics including the equivalent natural period for each bridge structure arranged in a row along the bridge axis direction, and measure the object to be measured by a predetermined seismic motion among the structure group consisting of each bridge structure. Measure the maximum response member angle that occurred in
The maximum response member angle is converted into an elastic response displacement using the elastic-plastic characteristic of the measurement object, and the elasticity of the structure group with respect to the earthquake motion using a correspondence relationship with the equivalent natural period of the measurement object Find the response characteristics
The elastic response displacement of the non-measurement object is calculated by applying the equivalent natural period of the non-measurement object excluding the measurement object among the structure group to the elastic response characteristic of the structure group,
The elastic response displacement of the non-measurement object is converted into a maximum response member angle using the elastic-plastic characteristic of the non-measurement object,
A damage level evaluation method for RC members, wherein the damage level of the non-measurement object is estimated from the maximum response member angle. Measuring means for measuring a maximum response member angle generated in the measurement object by a predetermined earthquake motion, which is installed in the measurement object, out of a group of structures including the bridge structures arranged in a line along the bridge axis direction When,
The maximum response member angle is converted into an elastic response displacement using an elasto-plastic characteristic including an equivalent natural period of the measurement object on which the measurement unit is installed, and a correspondence relationship with the equivalent natural period of the measurement object is Using an arithmetic processing unit for obtaining an elastic response characteristic of the structure group to the earthquake motion using,
The arithmetic processing unit calculates an elastic response displacement of the non-measurement object by applying an equivalent natural period of the non-measurement object excluding the measurement object to an elastic response characteristic of the structure group, and the elasticity An RC member damage level evaluation system, wherein the damage level of the non-measurement object can be estimated from the maximum response member angle by converting the response displacement into a maximum response member angle.

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