JPH01299963A - Method of re-clamping or repairing and reinforcing or load-reducing deformed existing structure - Google Patents

Abstract

PURPOSE: To repair and restore a deformed existing structure by adding a complementary support system to the deformed existing structure, elastically deforming the existing structure by applying a preload to this existing structure, and removing the preload after being joined to a deformed part in a frictionally connecting shape. CONSTITUTION: A complementary support system 2 is added to a frame 1 of an existing structure deformed by a cause of an earthquake. Next, a preload P is applied to the support system 2 to cause desired elastic deformation. Next, the existing structure is joined in a frictionally connecting shape by a method of filling concrete in a void 3 between the deformed part and a deformed part of the existing structure. Afterwards, the preload P applied to the support system 2 is removed, the support system 2 is returned to a former shape, and the deformed part of the existing structure is also restored according to this.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for retightening or repairing a deformed existing structure (building or building structure) and for strengthening or reducing the load thereof.

BACKGROUND OF THE INVENTION Conventional design and construction techniques employ a variety of different methods for prestressing buildings, such as prestressing concrete, which is widely used in bridge construction.

In the case of prestressed concrete structures, cables are used inside the concrete elements, which are pretensioned and anchored during construction, so that in this system the stresses within the concrete elements are generated internally. .

Another known method of pretensioning structures is Secretar, introduced in Mexico City in 1963.
Pr of ia deObras l'5blicas
Report by oyectos Tipo “Est
ructuras para Puentes'', in this case an inverted V
The method uses a steel beam with a shaped lower flange, inside which a pre-stretched cable is laid which is anchored to one end of the beam and which is then pre-stretched and connected to the rest of the beam. The ends are anchored in an effective manner, thereby creating internal stresses and elastic deformations in the beam. Cement mortar is filled under pressure into the 7-lunge holes configured in an inverted figure 7 shape.

In the two examples mentioned above, provision is required for installing the pretensioned cable, which must already be taken into account when the construction is initially designed.

(Problem to be Solved by the Invention) The problem of the present invention is to develop a method for retightening, repairing, reinforcing, and reducing loads that can be applied to structures that have already been constructed, such as existing house structures that have been damaged by earthquakes. The purpose is to provide a method that can be applied to restore.

[Means to solve the problem]

According to the method of the present invention proposed to solve the above problems, in a first step a supplementary bearing system is added to an existing structure, and in a second step this supplementary bearing system is added. to cause the desired elastic deformation of the bearing system, and in a third step, at least the preloaded and elastically deformed portion of the supplementary bearing system is retightened or repaired or strengthened and/or It is frictionally connected to the structure to be relieved and, in a fourth step, the preload on the supplementary bearing system is removed.

(Operations and Effects of the Invention) The method according to the present invention can be effectively carried out in the form described in claims 2 to 5.

The method according to the invention can also be applied to repair house structures damaged by earthquakes or to relieve loads on existing structures, especially foundations.

If the method according to the present invention is used, unlike the conventional techniques described above, it is possible to apply later tightening to an already completed structure (building or structure) that was not planned at the time of the original structure design. It is possible to perform processing.

Furthermore, the method according to the invention fundamentally differs from conventional methods in that the existing structure, together with the newly added support structure, reacts to the original loads supported solely by the existing structure. This load can be partially or completely transferred to a newly added support system.

A further difference from the previously known methods is that, in the method according to the invention, the material is preferably placed inside the structure to be pre-stretched and tensioned during the manufacturing process before this structure is put into use. Cables are used exclusively. However, the method according to the invention is not limited to the use of cables of this kind, but also to the attachment of materials to existing structures, such as frames, beams, arches, etc., as completely additional support structure systems. Also falls within the scope of the present invention. These materials can be installed after the structure is completed and after the structure is put into service. The method according to the invention can therefore also be implemented in combination with previously known structural systems, by adding to and integrating the complementary supporting structure system used in an effective manner into existing structures. It can therefore be said that this method is no longer a method for pre-tensioning, but a method for re-tensioning or reforming deformed existing structures and for strengthening or relieving their loads. .

Furthermore, in contrast to the prior art, the method according to the invention can be applied not only to concrete structures, but also to structures made of metal, wood and other materials, so that it can be applied to all types of structures, buildings and structures of different ages. There is also the fact that it has been adopted in Japan.

Moreover, the method according to the invention, unlike previously known techniques, allows for a wide range of materials that can be used for the supplementary support structure system; not only can metal, stone, wood and other materials be used; It is also possible to use any combination of these materials.

The method of the present invention for retrofitting an existing structure with a supplementary bearing system is also an improvement over previously known techniques.

(Embodiments) Next, the present invention will be described in detail with reference to embodiments shown in the accompanying drawings.

Figure 1 shows the frame (1) of a deformed structure that has already been constructed, and in this figure, the deformation caused by gravity acting on the structure is exaggerated to make it easier to see. It is.

FIG. 2 shows the addition of a supplementary support structure system (2) to an existing structure in the first step of the method according to the invention.

FIG. 3 shows the second step of the method according to the invention, in which the complementary bearing structure system (2) is preloaded with a force (P) in order to impart the desired elastic deformation to this system.

FIG. 4 shows the third step of the method according to the invention, in which the supplementary bearing structure system (2) is The preloaded and elastically deformed part (2°) of the is frictionally connected to the existing structure (1) to be renovated, so that the deformed part (2°) and the existing structure to be renovated (1) The gap (3) between the structure (1) and the structure (1) is filled with concrete, and this concrete has a preload force (
P) is allowed to harden before being removed. In this case, an admixture is added to the concrete to stabilize its volume.

FIG. 5 shows the overall structure of both frames after the preload force (P) has been removed according to the fourth step of the method according to the invention, as a result of which a new equilibrium exists between the two frame structures. The condition has been maintained and the original frame structure (1) has been retightened, restoring the original frame shape.

Furthermore, in most cases this step is followed by the joining of a complementary support structure system (2) to the renovated original structure (1) using additional fastening means (B), making both parts rigid as a single unit. It is especially effective if you keep it in a unit.

Next, we will give two examples that can be applied in practice.

Example 1: Columns and beams forming a supplementary support structure system, for example, in the case of a high-rise building in an urban area that has been damaged by an earthquake of considerable magnitude and which has to have some of its own weight removed from the structure. and are placed within the modified existing structure.

A preload is then applied to the center of each beam to give the beam an elastic downward deformation. In this deformed state, the elastically deformed part of the complementary support structure system and the structure to be renovated are bonded by mortar and volume stabilizing additives. If the preload is removed after this bonding process is completed, the attached beam will act upwards against the existing structure, allowing the original structure to transfer some of the load it was supporting to the newly added bearing structure. You can switch shoulders by If you adopt such a method,
It is possible to remove some of the loads acting on existing deformed high-rise structures. The safety of the structure obtained by adopting this method according to the invention is increased compared to that achieved with the original structure, and in addition to achieving a supplementary support action, Various conditions will also be improved.

Example 2 This example concerns load reduction on foundations. In this case, each foundation block (4) of an industrial facility is designed to increase the supporting capacity of the crane track installed between the facilities, and by extension, to increase the supporting capacity of the foundation itself. Supplementary bearing structure system or additionally installed. This method consists of the following four steps.

1st step: As shown in Figures 6 and 7, four piles (5) are driven next to each foundation block (4) that has already been placed; (5) Upper end surface (
6) is made to protrude upward from the base upper edge (7). Then, as shown in FIGS. 8 and 9, one supplementary bearing beam (8) and (9) each on each two wooden piles (5) facing each other is attached to the foundation block (4).
) will be located on both sites.

Second step: As shown in Figs. 1O and 11, the two complementary bearing beams (8), (9) are each Preloaded.

As a result, it is elastically deformed downward as shown in the figure.

Third step: These two complementary elastically deformed bearing beams (8), (9) are then attached to the foundation block (4) by means of expansions, dowels, etc., as shown in FIGS. 12 and 13. ) is fixedly connected to the

Fourth step: Finally, as shown in Figures 14 and 15, the preload force C
When P) is removed, a part of the load previously applied to the foundation is removed, and the difference is taken over by the pile (5), resulting in a new equilibrium state.

The method according to the prior art, in which the pile was connected to the original foundation and the previous bearing base removed, so that the pile had to take the full load of the existing structure, and the new method according to the invention, The difference from the typical method is clear from the second example described above.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an existing deformed structure frame with its deformation exaggerated, and FIG.
3 is a diagram showing the second step of the method according to the present invention, FIG. 4 is a diagram showing the third step of the method according to the present invention, and FIG. 5 is a diagram showing the fourth step of the method according to the present invention. Figure shown, No. 6
7, 8 and 9 are diagrams showing the first step of the second example of the method of the present invention, and FIGS. 10 and 11 are diagrams showing the second step of the second example. , Figures 12 and 13
The figure shows the third step of the second example, Figure 14, and the first
FIG. 5 is a diagram showing the fourth step of the second example. l... Frame, 2... Supplementary support structure system, 2'... Elastically deformed part of the support structure system, 3... Between the deformed part and the existing structure. void,
4...Foundation block, 5...Pile, 6...
・Pile top end surface, 7...Foundation top edge, 8.9...
Supplementary bearing beam. Patent applicant Holm Ortega Beltran Agent Satoshi Shimizu Haka 2
NameFig, 14 Fig
, 15 Procedural Amendment (Voluntary) (Method) % Formula % l Indication of Case Patent Application No. 1-86692 2 Title of Invention Re-tightening or repairing an existing structure that has been transformed, and strengthening or reducing the load on it Method 3 Relationship with the case of the person making the amendment Patent applicant name Holm Ortega Beltran 4 Agent postal code 651 Address 7-1-1-5 Kumoidori, Chuo-ku, Kobe City Power of attorney subject to amendment and drawings 6 Contents of amendment (1 ) Supplement the power of attorney and the translation of the power of attorney as shown in the attached sheet. (2) Engraving of drawings (no changes in content). Attached documents (1) Power of attorney and its translation (1 copy each) (2) Drawings (1 copy) (3) Upper middle 1 copy or more

Claims (7)

[Claims] (1) Retighten or repair deformed existing structures;
and a method for strengthening or offloading the structure, which includes, as a first step, adding a supplementary bearing system to an existing structure and, as a second step, causing the supplementary bearing system to undergo the desired elastic deformation. a structure in which this bearing system is preloaded as a third step and, as a third step, at least the preloaded and elastically deformed parts of the supplementary bearing system are to be retightened, repaired or strengthened and/or relieved; and, as a fourth step, removing the preload on the supplementary bearing system. 2. A method according to claim 1, characterized in that a frame, beam, arch or similar structural system to an existing structure is used as a supplementary support system. (3) The supplementary bearing system is preloaded using weights, hydraulic jacks, winches, or tire forts.
The method described in section 2). (4) In the third step, the frictional connection between the two structures is performed by welding or by using screws, concrete, or dowels. The method described in any one of paragraph (3). 5. A method according to claim 1, characterized in that a supplementary support system of steel or reinforced concrete or wood is used. (6) Claim No. 1 is characterized in that it is applied to repair a house structure damaged by an earthquake.
) to (5). (7) Claim (1) is characterized in that it is applied to reduce the load on existing structures, especially foundations.
The method according to any one of paragraphs to (5).