JPH0953248A - Structure coping with great earthquake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display the effect (a response control effect) of energy absorption to horizontal force at the time of an earthquake, and to use the pile head section of a bearing pile even to the damage, etc., of the pile head section. SOLUTION: A structure base 2 in the lower section of a structure 1 is placed slidably on the top face of a foundation base 4 in the ground borne by bearing piles 3 through a separation layer 5, and the ground structure 1 is constructed on the structure base 2. The internal ground of a landslide protection wall 9 built on the outer circumference of the foundation base 4 is replaced with sand up to a section in the vicinity of a bearing layer 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of construction, and more specifically, it exerts an energy absorbing effect (seismic isolation effect) on a horizontal force during an earthquake, and has an unexpectedly large amount. Even if the pile head of the support pile is damaged by the earthquake and the structure tilts slightly, the head of the pile and the tilt of the structure are repaired, and it can be used soundly thereafter. , About the structure for large earthquakes.

[0002]

2. Description of the Related Art Conventionally, various researches and developments have been made on structures for large earthquakes. For example, Japanese Patent Laid-Open No. 2-2
The sliding seismic isolation type offshore structure described in Japanese Patent No. 82523 separates the bottom plate part of the gravity type offshore structure to be installed on the seabed into a foundation side plate and a body side plate, and a horizontal force above a certain level. It is configured to allow sliding on the contact surface between the base side slab and the main body side slab. The sliding action provides seismic energy absorption and seismic isolation.

Next, the seismic isolation device for a structure described in Japanese Patent Laid-Open No. 57-81569 has a short-cycle external force (horizontal force).
In contrast, the structure was constructed in a state where relative displacement with respect to the surrounding ground was possible, a seismic isolation mechanism was installed between the structure and the surrounding ground, and the structure was It is designed to be restrained.

[0004]

It is clear that the structures for large earthquakes described in the above-mentioned respective publications have a structure in which the effect of energy absorption on the horizontal force is taken into consideration. But that's all. On the other hand, the magnitude of the earthquake and the extent of the damage cannot be predicted in advance, which is the case with past cases. That is, even if the structure slides due to horizontal force and the action of energy absorption works, such action effect is still insufficient,
The pile head of the support pile that supports the foundation of the structure is severely damaged,
It is not uncommon for structures to tilt or even collapse. However, in each of the above-mentioned conventional techniques, if the pile head of the support pile is damaged or the structure is greatly tilted, there is no means for coping with it, and thereafter, a dangerous structure that is not suitable for service. I had no choice but to dispose of it.

Therefore, it is an object of the present invention to use the structure for the time being even if the pile head of the support pile supporting the foundation of the structure is damaged or the structure is tilted. The purpose of the present invention is to provide a structure for a large earthquake that is constructed so that the pile head and the tilted structure can be repaired.

[0006]

[Means for Solving the Problems] As a means for solving the above-mentioned problems of the prior art, a structure corresponding to a large earthquake according to the invention of claim 1 is an upper surface of an underground foundation base supported by support piles. In that, the structure base of the lower part of the structure is slidably placed via the separation layer, and the structure on the ground is constructed on the structure base, and the earth retaining structure constructed on the outer periphery of the foundation base. The inside ground is characterized by being replaced by sand up to the support layer.

At the outer peripheral position of the foundation base described in claim 1, a slip stopper for regulating the sliding limit of the structure base thereon is raised, and between the slip stopper and the outer peripheral surface of the structure base. Is filled with cushioning material. Furthermore, a cavity for jack installation is provided at a position near the outer peripheral column of the structure according to claim 1 at a boundary portion between the structure base and the foundation base, and the cavity base is provided in the cavity. A jack for repairing the structure that pushes the structure base upward by taking a reaction force is installed vertically upward, and a vertical observation hole that penetrates the foundation base from the position of the cavity and reaches the head of the support pile directly below. Is also provided. The observation holes are not limited to the support piles on the outer periphery of the structure, and are provided so as to reach the heads of the respective support plates located inside the structure.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A structure for a large earthquake according to the present invention will be described in a constructional order by replacing the inner ground of a mountain retaining structure built around the structure with sand, preferably to the depth of the supporting layer. The sand layer is used as the ground, and it is pre-compacted so as to exert a supporting force according to the amount of the load of the structure. Then, the support pile is constructed as, for example, a cast-in-place concrete pile, and the underground foundation base supported by the support pile is constructed so that its upper surface becomes a horizontal flat surface. Therefore, the foundation base is also regarded as an element corresponding to the head connection of the support pile. A separation layer is formed on the horizontal upper surface of the foundation base by means such as coating with asphalt, and a structure base corresponding to the foundation of the upper structure is horizontally formed on the separation layer through the separation layer. Build slidably. The structure base may be an independent foundation, beam-type structure. Buildings and other superstructures are built on the structure base. As the upper structure, roads, bridge piers, tower structures, etc. are also applicable.

When the structure having the above-mentioned structure receives a large horizontal force due to an earthquake, it slips between itself and the base to absorb seismic energy and exert the seismic isolation effect of the structure. And even if an unexpectedly large earthquake causes damage such as damage to the pile heads of the support piles,
Since the foundation base is immediately and strongly supported by the sand layer ground that replaces the support piles, it is possible to avoid a disaster that suffers great damage from collapse or near collapse. In addition, it is possible to prevent damage to the pile head and a dangerous situation in which the structure tilts gradually over time. Therefore, even if the building is slightly tilted, it will not cause damage such as hindering its use.

Next, according to the present invention, a non-slip member for restricting the sliding limit between the structure base and the base member is constructed in the shape of a vertical wall at the outer peripheral position of the base member. It is also implemented with a structure in which a cushioning material such as gravel or earth and sand is filled between the outer peripheral surface of the base. In this way, it is possible to prevent unduly large sliding and displacement between the foundation base and the structure base.

Further, according to the present invention, a cavity for jack installation is provided in the structure base at a boundary portion between the foundation base and the structure base at a position near the outer peripheral pillar of the structure, and in the cavity, A structure-repairing jack is installed vertically upward by pushing the structure base upward by taking a reaction force against the foundation base. Further, it is also implemented with a configuration in which a vertical observation hole is provided which penetrates the foundation base from the position of the hollow portion and reaches the head of the support pile directly below. Therefore, even if a big earthquake
When the pile head of the support pile is damaged and the structure is tilted, the worker first descends into the cavity and inserts an observation means (equipment) such as a fiberscope into each observation hole. It is possible to obtain information such as the degree of damage to the pile head, the possibility of repair, and consideration of suitable means for repair.
After that, cement milk can be injected using the observation hole to repair the damaged pile head. Furthermore,
The jack in the cavity works to eliminate the inclination of the structure and restore it to a normal posture. However, the repair of the pile head and the elimination of the inclination by jacking up will be delayed in time depending on the degree of damage and the usage conditions of the structure. When the inclination is eliminated by jacking up, concrete is filled or cement milk is injected between the structure base and the foundation base to permanently fix the restored state. Since it is not possible to predict which position of the support pile will be damaged in a plan view of the structure, it is convenient to preliminarily provide the observation holes to the pile heads of all the support piles.

[0012]

EXAMPLE An example of the present invention shown in the drawings will be described below.
The embodiment shown in FIG. 1 is a building 1 which is an example of a ground structure.
The structure base 2 of 1 is formed on the upper surface of the base base 4 which is constructed like a head tie of the support piles 3 and which is formed in a horizontal flat surface shape.
It is mounted so that it can slide horizontally. A separation layer 5 is formed by coating the entire surface of the base 4 with asphalt, and the separation layer 5 is configured to smoothly realize the above-mentioned sliding. At the outer peripheral position of the foundation base 4, a slip stopper 6 that restricts the sliding limit is erected in a vertical wall shape. Between the anti-slip 6 and the outer peripheral surface (side surface) of the structure base 2, a cushioning material 7 such as gravel or earth and sand is provided on the ground G. It is filled to the same level as L. The support piles 3 are constructed as cast-in-place concrete piles that reach the support layer 8, and the ground surrounded by the mountain retainers 9 on the outer periphery of the support piles 3 can be entirely replaced with sand and can support the load of the building 1. As described above, the sand layer ground 10 is sufficiently compacted.

FIG. 2 shows a plan view of the building plane including the arrangement of the columns 1a of the building 1 and the arrangement of the jacks 11 with respect to the outer peripheral columns of the building. A pair of jacks 11 are installed symmetrically on both sides of the outer peripheral column 1a. FIG. 3 shows the details of the arrangement structure of the outer peripheral column 1a and the jack 11. FIG. 3 also shows that the position of the pillar 1a and the position of the support pile 3 are arranged so as to be planarly aligned. FIG. 3 also shows that a hollow portion 12 having a wide lower portion is provided in the structure base 2 at a boundary portion with the foundation base 4 at a position near the pillar 1a, and the hollow portion 12 has a wide lower portion. 1
Vertical manhole 1 that allows people and equipment to enter and exit
3 is provided. In the hollow portion 12, a plurality of repair jacks 11 are installed vertically upward so as to lift the structure base 2 upward by applying a reaction force to the foundation base 4 to eliminate the inclination of the building 1. The total capacity of the jacks 11 installed on each pillar is sufficient for the repair work to push up the building.

Further, an observation hole 14 is provided in the cavity 12 so as to avoid the position of the jack 11 and penetrate the foundation base 4 to reach the pile head of the support pile 4 immediately below. The diameter of the observation hole 14 is set to about 10 cm so that observation equipment such as a fiberscope can be inserted and cement milk can be injected later. This observation hole is preferably provided for all the support piles. The jack 11 is installed in a non-operating state in normal times, but in some cases, it is damaged by a large earthquake, and is carried into the cavity 12 at the stage where it is necessary to restore the inclination of the building 1. It is also possible to implement the method used by using.

[0015]

According to the structure for large earthquakes according to the present invention, the horizontal force at the time of earthquake can absorb the energy by sliding the structure, and seismic isolation effect can be obtained. And even if the pile head of the support pile is damaged due to an unexpectedly large earthquake and the structure inclines, the sand layer ground will be used to secure short-term support and stop the damage. It makes it possible to restore the head, the inclination of the structure, so that the structure can be used as in the previous normal state.

[Brief description of drawings]

FIG. 1 is an elevational view showing an outline of the structure of a large earthquake-resistant building according to the present invention.

FIG. 2 is a plan layout view of the building.

FIG. 3 is a cross-sectional view showing arrangement details of a pillar, a support pile, and a jack.

[Explanation of symbols]

 3 Support pile 4 Foundation base 2 Structure base 5 Separation layer 1 Building (structure) 9 Mountain retaining 10 Sand layer ground 6 Anti-slip 7 Buffer material 1a Column 12 Cavity 11 Jack 14 Observation hole

Claims (4)

[Claims] 1. A structure base under a structure is slidably mounted via a separation layer on an upper surface of an underground base supported by a support pile, and a structure on the ground above the structure base. A structure for a large earthquake, characterized in that the structure is constructed, and that the inner ground of the mountain retaining structure constructed on the outer periphery of the foundation base is replaced with sand up to the vicinity of the support layer. 2. A non-slip for restricting a sliding limit of a structure base on the foundation base is raised at an outer peripheral position of the base, and a cushioning material is filled between the non-slip and the outer peripheral surface of the structure base. The structure for large earthquakes according to claim 1, characterized in that 3. A hollow portion for installing a jack is provided at a position near the outer peripheral column of the structure and at a boundary portion of the structure base with the foundation base, and a reaction force is applied to the foundation base in the cavity. Push the structure base upward with a jack for repairing the inclination of the structure is installed vertically upward, and a vertical observation hole that penetrates the foundation base from the position of the cavity and reaches the head of the support pile directly below is provided. The structure for large earthquakes according to claim 1, which is characterized by being provided. 4. The structure for a large earthquake according to claim 1, wherein the observation hole is provided so as to reach the head of each support pile located inside the structure. .