JPH0238627A - Rebuilding of existing building - Google Patents

Abstract

PURPOSE:To make it possible to carry out a foundation work of a building to be rebuilt while maintaining an existing building by excavating a tunnel under the existing building and excavating under a PC slab to build an underground space after building the PC slab. CONSTITUTION:Cut-off walls 10 and 10 are provided in the vicinity of a prospective rebuilding side to build a vertical shaft 1, and a tunnel 2 in such a state that existing pipes 31 penetrated is excavated throughout the whole underground area of existing buildings 3 and 3. Then, foundation pillars 4 and are driven under the tunnel 2, successively a PC slab 21 is built on the slab surface of the tunnel 2, and new foundation pillars 4, 4 and the existing piles 31... together with the PC slab 21 are integrated into one unit. After that, the under side of the PC slab 21 is excavated to form an underground space 5, and concrete is placed to the internal surface thereof to build an underground facility 7. A ground facility is rebuilt after transferring facilities of the existing buildings 3 and 3 to the newly built underground facility 7.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to the reconstruction of an existing structure, in which the existing structure above ground is used and the foundation of the structure to be reconstructed is constructed underground. Regarding construction methods.

<Conventional technology> In order to rebuild an existing structure such as an apartment complex over a large area, it is necessary to: ■ Relocate or demolish the existing structure on the ground, ■ Perform excavation work or foundation work, The underground part of the structure is constructed, and finally the above-ground part is constructed above the foundation.

<Problems to be Solved by the Present Invention> The conventional techniques for rebuilding existing structures described above have the following problems.

<B> During the reconstruction work of the existing structure, it will be impossible to use the existing structure.

Therefore, it is desired to propose a technology that allows rebuilding existing structures while maintaining them.

<Exposure> Generally, when rebuilding an existing structure, a certain amount of temporary space is required on the land.

Additionally, a temporary relocation space is also required to temporarily store various items stored in the existing structure.

However, with land prices on the rise, it is becoming increasingly difficult to secure these spaces.

<Object of the present invention> The present invention has been made in view of the above points, and an object thereof is to provide the following method for rebuilding an existing structure.

(a) Reconstruction work can be carried out while maintaining the existing structure,
Reconstruction method for existing structures.

<Explanation> A method of rebuilding existing structures that allows for effective use of land.

<Configuration of the Present Invention> An embodiment of the method for rebuilding an existing structure according to the present invention will be described below with reference to the drawings.

<B> Tunnel excavation (Figure 2) Vertical shaft 1 will be constructed around the planned reconstruction site.

At this time, a water stop wall 10 is constructed as necessary.

Then, a tunnel 2 is excavated from the shaft 1 to the entire underground part of the planned reconstruction site.

The excavation method for tunnel 2 is based on the existing structure 3, which is erected on the ground.
Select according to the basic form.

As the excavation method, for example, if the foundation type of the existing structure 3 is a direct foundation, the shield method or the Metsusel method is adopted, and in the case of a pile foundation, the Metsusel method or the like is adopted.

When excavating the tunnel 2, auxiliary construction methods such as the bi-roof construction method and the chemical injection method are used in combination as necessary.

In addition, if the foundation type of the existing structure 3 is a pile foundation, the existing piles 31 and the tunnel 2, which constitute a part of the foundation of the existing structure 30,
However, in order to prevent ground subsidence, the tunnel 2 is excavated with the existing piles 31 passing through it.

<Entrance> Construction of foundation piles (Figure 2) The foundation piles 4 extending below the tunnel 2 are constructed using the reverse circulation construction method.

〉Construction of PC Slab (Fig. 2.3) Next, a PC slab 21 is constructed on the slab surface of the tunnel 2.

The PC slab 21 is constructed integrally with the foundation pile 4 and the existing pile 31.

This PC slab 21 not only functions as a ceiling plate to prevent earth and sand from collapsing during underground construction, but also ultimately becomes a constituent material of the structure.

The method for constructing the PC slab 21 is to place concrete on the slab surface of the tunnel 2 by arranging PC steel in a loop along with reinforcing bars so as to surround the foundation piles 4, and then placing PCM material in the middle of the slab. You can use a method to maintain tension.

As for the prestress introduction method for the PC slab 21, an optimal known prestress introduction method is adopted in consideration of the height of the tunnel 2, the construction range, etc.

Further, if necessary, the upper cavity within the tunnel 2 is filled with foamed mortar.

<2> Excavation under the slab (Fig. 4) After constructing the PC slab 21, which is integrated with the four groups of foundation piles,
An underground space 5 is formed by excavating below the PC slab 21.

Since the total load above the PC slab 21 is supported by the four groups of foundation piles integrated with the PC slab 21, collapse during excavation of the underground space 5 is prevented.

When excavating below the PC slab 21, if a method is adopted in which a tunnel for removing excavated earth that communicates with the underground space 5 is constructed in advance, a large amount of earth can be removed with high efficiency.

<E> Construction of underground facilities (Fig. 5) Concrete is poured on the inner surface of the underground space 5 to construct the underground facilities 7.

Then, the facilities of the existing structure 3 on the ground side are relocated to the underground facility 7 as necessary.

<E> Construction of ground facilities (Figure 6) Finally, the aboveground facility 8 is constructed above the underground facility 7.

In addition to constructing the above-ground facility 8 by sequentially removing three groups of existing structures, it is also possible to construct the above-ground facility by removing three groups of existing structures one by one.

Effects of the Present Invention> Since the present invention is as explained above, the following effects can be obtained.

<B> Foundation work for the reconstructed structure can be carried out while maintaining the existing structure above ground.

Furthermore, since the above-ground facilities are constructed after the underground facilities of the reconstructed structure are completed, the period during which the existing structure is discontinued can be kept to a minimum.

<Exit> The completed underground facility can be used as a space for relocating existing structures above ground.

Kuha> Temporary space around the above ground area can be kept to a minimum.

(2) Effective use of land above ground can be achieved.

Kuho〉PC slabs can be used not only as struts for water-stop walls and earth-retaining walls, but also as a final part of a structure.

〈〈〈〈〉It is suitable for reconstruction work of large-scale markets and residential complexes.

[Brief explanation of the drawing]

Fig. 1 2 is an explanatory diagram of one embodiment of the present invention, which is a partial sectional view during construction of an underground facility Fig. 2: longitudinal sectional view of a tunnel during tunnel excavation Fig. 3;
Figure 4: Vertical cross section of the tunnel when constructing the C slab Figure 5: Vertical cross section when constructing underground facilities Figure 6: Cross section when constructing above ground facilities

Claims (1)

[Claims] (1) Excavate a tunnel across the entire underground area of the planned reconstruction site while maintaining the existing structures above ground, and construct foundation piles that extend downward on the slab surface of the tunnel. Next, on the slab surface of the tunnel, A prestressed PC slab is constructed that is integral with the foundation pile, and the foundation piles are used to support the ground through the PC slab.
A method for rebuilding existing structures, in which underground facilities are constructed by excavating below the C slab, and above-ground facilities are constructed that are integrated with the above-mentioned underground facilities while removing the existing above-ground structures.