JP3021393U - Underground structure with damage detection function - Google Patents

Abstract

(57) [Abstract] [Purpose] A sensor with a damage detection function is installed in advance in underground structures such as water pipes and gas pipes that make up foundation piles and lifelines, and earthquakes and unequal subsidence, etc. The purpose is to be able to detect the damaged part of the buried structure by the ground quickly. [Structure] A lead wire was previously attached to the outer periphery of the foundation pile, water pipe, gas pipe, etc. in the longitudinal direction, and resistance wires were connected to the lead wire at predetermined intervals.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an underground buried structure having a damage detection function. More specifically, precast piles and cast-in-place piles used as foundation piles for building structures, and underground buried structures such as water pipes and gas pipes used as lifelines are equipped with damage detection means in advance. It relates to underground buried structures that have a damage detection function.

[0002]

[Prior art]

 It is extremely important to know the integrity of underground structures such as foundation piles in order to ensure the safety of superstructures. Conventionally, the method of confirming this integrity is to strike the head of the pile with a hammer and measure the reflection of the shock wave to estimate the integrity, or to make a boring hole beside the pile. A magnetic sensor is inserted into this hole and the pile length is estimated by the reaction of the magnetic sensor. In addition, as a method of detecting the location where the lifeline is damaged due to an earthquake, etc., the method of excavation relying on the drawings at the time of burial and visual confirmation is used.

[0003]

[Problems to be solved by the device]

 However, these conventional methods have the following major problems. (1) With the method using shock waves, confirmation after construction is virtually impossible. For this reason, the head of the foundation pile cannot be directly hit when it is already installed. This means excavating until the footing is exposed and hitting it indirectly from above the footing. As a result, multiple reflections within the footing or multiple reflections from the upper building occur, making evaluation of measurement data extremely difficult. That is, it is not possible to obtain highly reliable inspection results. Also, in the case of large diameter cast-in-place piles or piles with a relatively long pile length, the shock wave is attenuated and the tip reflection is not removed, so it cannot be inspected. (2) The method of drilling a hole on the side of a pile and setting a sensor requires a considerable amount of labor for drilling, and in the case of an existing one, it is limited to the pile installed on the outer periphery of the building. (3) In addition, in the case of a lifeline, excavation work requires a great deal of labor, and a considerable amount of time is required from confirmation to repair. In other words, it takes time to recover. In any case, the conventional confirmation method has a problem in its reliability although its application range is limited and a great deal of labor is required.

An object of the present invention is to solve the problems of the conventional confirmation method and to provide an underground buried structure having a damage detection function that enables rapid detection of a damaged portion. Is.

[0005]

[Means for Solving the Problems]

 Therefore, what measures were taken was to install or bury the resistance wire in advance in underground buried structures such as water pipes and gas pipes that compose piles and lifelines, and then to lay them. It is possible to confirm the presence or absence of breakage by measuring the resistance value of the resistance wire after being buried by using a tester. That is, lead wires are assembled along the longitudinal direction of piles, water pipes, or gas pipes that will be underground structures, and resistance wires are installed at predetermined intervals on this lead wire. The point of failure is to be detected by measuring the resistance value of the resistance wire after driving or embedding.

[0006]

[Action]

 In this invention, the lead wire is previously assembled to the underground buried structure itself, and the resistance wire is incorporated at a predetermined interval in the lead wire. Therefore, after the structure is cast or buried, the resistance wire is installed. The position of the damaged part can be easily confirmed by measuring the resistance value of.

[0007]

【Example】

 Further, the present invention will be specifically described based on an embodiment shown in the drawings. First, FIG. 1 shows an example in which the present invention is applied to a foundation pile of a building, and shows the principle of measuring the location of damage. As shown in the figure, the lead wire 2 is assembled along the longitudinal direction of the pile 1. As a method of assembling the lead wire 2, in the case of a precast pile, the lead wire 2 is incorporated into each unit pile member 1a, 1a ... In the manufacturing process at the factory site, and the resistance wire 2a is attached to the lead body 2 as shown in the figure. Wiring was done in parallel so that the longitudinal direction was divided at regular intervals. The ends of the lead wires 2 of each unit pile member 1a are connected by using jack terminals 2b. That is, the unit pile members 1a are connected via the jack terminals 2b in accordance with the driving process. Incidentally, as a means of connection, the connection may be made without using the jack terminal 2b. As the lead wire 2, a vinyl covered wire was used. When the pile 1 is piled in the field, the lead wire 2 and the resistance wire 2a may be respectively wired according to the case of the precast pile. Therefore, if necessary, a tester T can be connected to the lead wire 2 and the damaged portion can be confirmed from the resistance value. For example, as shown in Fig. 1, if the middle part of the pile 1 is damaged and the lead wire 2 is broken, the resistance value due to the tester T will change, so check the damaged part by comparing with the normal case. You can

FIG. 2A is a partial front view of the pile including the joint portion 3 of the precast pile 1. FIG. 2B is a vertical cross-sectional view of FIG. 2A and shows a wiring procedure of the lead wire 2 and the resistance wire 2 a. As shown in the figure, the lead wire 2 and the resistance wire 2a are built in advance along the reinforcing bar 4 in the factory manufacturing process. A jack terminal 2b was attached to the end of the lead wire 2 corresponding to the joint portion 3, and the jack terminal 2b was used for connection at the field joining stage.

FIG. 3 shows an embodiment in which the present invention is applied to a water pipe 5 as a lifeline. In this case, the resistance wire 2a was wired to the lead wire 2 at a constant pitch. Therefore, as shown in FIG. 4, when an external force such as an earthquake or unequal subsidence causes breakage cracks or the like, the lead wire 2 is broken, and as a result, the lead wire 2 is disconnected from the tester T as shown in FIG. It is possible to quickly find the damaged part by connecting the and connecting it and measuring the resistance value.

[0010]

[Effect of device]

 Since this invention has a structure in which a resistance wire is built into a foundation pile, a water pipe or a gas pipe in advance, if this foundation pile or water pipe or gas pipe is installed or embedded as an embedded structure, it will not be installed. Even if the piles, water pipes or gas pipes are damaged due to an earthquake or uneven settlement of the ground as well as the integrity immediately after burial, the damaged parts can be found easily and quickly by using a tester. It is possible to take appropriate measures such as repairs.

[Brief description of drawings]

FIG. 1 shows an example of a case where the present invention is applied to a foundation pile of a building, showing a principle of measuring a damaged portion.

FIG. 2 (A) is a front view of a main part including a joint part when the present invention is applied to a precast pile,
(B) is a longitudinal sectional view of (A).

FIG. 3 shows an embodiment in which the present invention is applied to a water pipe as a lifeline.

FIG. 4 is a side view of a damaged portion when the water pipe is damaged by an external force such as an earthquake or uneven settlement.

[Explanation of symbols]

 1 …… Pile 1a …… Unit pile member 2 …… Lead wire 2a …… Resistance wire 2b …… Jack terminal 3 …… Joint part 4 …… Reinforcing bar 5 …… Water pipe (lifeline) T …… Tester

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[Procedure amendment]

[Submission date] September 28, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 3

[Correction method] Change

[Correction content]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Toshinasa Nagao 1-25-1 Nishishinjuku, Shinjuku-ku, Tokyo Taisei Corporation

Claims (3)

[Scope of utility model registration request] 1. A lead wire is previously assembled along a longitudinal direction to a buried underground structure such as a water pipe or a gas pipe constituting a pile or a lifeline, and a resistance wire is incorporated at a predetermined interval in the lead wire. An underground buried structure having a damage detection function, which is characterized by: 2. The underground buried structure having a damage detecting function according to claim 1, wherein the resistance wire is incorporated in parallel with the lead wire at a predetermined interval. 3. When the underground structure is formed by joining unit pile members or unit water pipes or unit gas pipes, the lead wires of each unit pile member, unit water pipe or unit gas pipe are connected via jack terminals or the like. The underground buried structure having the damage detection function according to claim 1 or 2, wherein the underground buried structure is configured so as to be connected with each other.