JPS6046216B2 - Pile foundation with underground brace made of triangular members - Google Patents

Description

[Detailed description of the invention] This invention relates to a pile foundation with an underground phrase.

In general, support piles have a large vertical bearing capacity but a small horizontal resistance force. However, in the case of buildings standing on soft ground or buildings without basements, most of the horizontal force caused by earthquake force and wind pressure is received by the horizontal resistance force of the support piles.
Buildings standing on soft ground or without basements had major structural problems. Therefore, recently, underground walls made of cast-in-place concrete or precast concrete plates and underground phrases made of steel frames are installed between the support piles driven into the ground, thereby preventing earthquakes, wind, etc. Pile foundations with underground walls are widely used because they can increase the horizontal bearing capacity and horizontal force rigidity of support piles against external forces, and reduce displacement.

However, due to the nature of the work, installing an underground wall made of cast-in-place concrete using conventional pile foundations with underground walls requires a great deal of time and effort, and a long construction period. Due to their shape, it was necessary to dig an excavation trench to install an underground wall or an underground phrase made of steel frames, which required extra time and effort.

In addition, in the case of underground walls made of precast concrete plates or underground phrases made of steel frames, it is possible to effectively absorb errors in the spacing dimensions of the foundation piles due to variations in the installation spacing of the foundation piles and the slope of the foundation piles. Nakatsuta. This invention was proposed to solve the above-mentioned conventional problems.
It has extremely high horizontal bearing capacity and horizontal rigidity as a pile foundation, as well as earthquake resistance, and is effective as a countermeasure against liquid in sandy ground.

In addition, the present invention provides a pile foundation with an underground phrase that can shorten the construction period, simplify the construction, save labor, and significantly reduce the construction cost, and can extremely easily absorb even a single error in the spacing between the foundation piles. The purpose is to In the pile foundation with underground phrases made of triangular members according to the present invention, the foundation piles are appropriately isolated and installed in the ground, and underground braces made of a plurality of triangular members are installed in the ground between the foundation piles as the foundation piles. It is installed in one piece.

According to this invention, since the underground brace is provided integrally with the foundation pile, the horizontal strength, horizontal rigidity, and earthquake resistance of the foundation pile are extremely high. In addition, during construction, the structural members of the underground brace are formed into a substantially triangular shape, so it is possible to install the underground brace by driving it in. As a result, the work of excavating an excavation trench in which to install the underground brace can be omitted. It is possible to shorten the construction period, simplify the construction, save labor, and reduce the construction cost. Furthermore, since the underground brace is made up of a plurality of triangular members, dimensional errors in the foundation girder spacing can be absorbed very easily at the joints of these triangular members. The underground braced pile foundation according to the present invention will be explained below with reference to an embodiment illustrating the underground braced pile foundation. 1, and install an underground brace 3 consisting of a plurality of triangular members 2, 2 in the ground between the foundation piles 1, 1.
, 1 are installed integrally.

Joints 4, 4 having a substantially T-shaped cross section that are continuous in the longitudinal direction of the foundation piles 1, 1 are formed by welding or otherwise fixing a shape material having a substantially T-shaped cross section to the sides of the foundation piles 1, 1. has been done.

The foundation piles 1, 1 are built into the ground by driving or embedding the joints 4, 4 facing each other. The triangular members 2 and 2 are made of extremely rigid metal plates or precast concrete plates. At the side edge thereof, an engaging portion 5 having a substantially lip groove-shaped cross section and engaged with the joint portion 4 is formed continuously in the vertical direction of the triangular portion 2. The opening surface of the lower end of the engaging part 5 has an opening hole 6 in the center thereof with a T-shaped cross section corresponding to the cross-sectional shape of the joint part 4, and the other parts are closed! It's blocked. Furthermore, reinforcing ribs 7 and the like are formed on the side and upper edges of the triangular member 2. The triangular members 2, 2 are installed in the ground between the foundation piles 1, 1 by driving or embedding, and the engaging part 5 is engaged with the joint part 4, and the engaging part 5 is filled with mortar, concrete, etc. The triangular members 2, 2 facing each other are connected with a plurality of bolts and nuts 9, so that they are integrated with the foundation piles 1, 1. Code 10 and 11,11
are underground beams and footings constructed on a pile foundation with underground braces; underground beams 10 and footings 11,
11 connects shear connectors 12, 12 such as stud dowels and stud bolts to the upper end of the underground brace 3 on the underground beam 10.
and the footings 11, 11 are made to protrude and be fixed thereto, so that they are integrated with the foundation with underground braces.
In construction, first, the foundation piles 1, 1 are properly isolated in the ground, the joints 4, 4 are opposed to each other, and the foundation piles are erected by a driving-in type or an embedded type.

Next, the triangular members 2, 2 are engaged with the engaging portion 5 through the opening hole 6 in the joint portion 4, and installed by a driving or embedding method while being guided by the joint portion 4, and the opposing triangular members 2 , 2 are connected with bolts and nuts 9, 9, and the joints 4,
4 is filled with a filler 8. Next, underground beams 10 and footings 11, 11 are constructed. Incidentally, the earth and sand that adheres to the surface of the joint portion 4 when the foundation piles 1, 1 are erected can be scraped off by the peripheral edge of the opening hole 6 when the triangular member 2 is erected. 5 and 6 show other embodiments of the present invention. In FIG. 5, foundation piles 1, 1 and opposing triangular members 2, 2 are integrated via an underground beam 10. There is.

In FIG. 6, in addition to the embodiment of FIG. 5, the beveled edges of the triangular members 2, 2 are formed in an arch shape. As described above, the pile foundation with underground braces made of triangular members according to the present invention has extremely high horizontal bearing capacity, horizontal rigidity, and seismic resistance as a pile foundation because the underground braces are provided integrally with the foundation pile, and it is suitable for use on sandy ground. It is also effective as a countermeasure against liquefaction.

Furthermore, during construction, since the structural members of the underground brace are formed into a substantially triangular shape, it is possible to install the underground brace by driving it in, thereby eliminating the need to excavate an excavation trench in which to install the underground brace. It is possible to shorten the construction period, simplify the construction, save labor, and reduce construction costs. Furthermore, since the underground brace is made up of a plurality of triangular members, dimensional errors in the spacing between foundation piles can be easily absorbed at the joints of these triangular members. In addition, since the foundation pile and the triangular member are each constructed in a split manner, the foundation pile and the triangular member can be installed separately in the ground, making it relatively easy to drive, etc. even when the size is increased. It has extremely good workability.

Furthermore, since the load does not become bulky when transported, stocked, etc., it is extremely easy to handle and extremely practical.

[Brief explanation of drawings]

1 to 3 are process diagrams showing a method of constructing a pile foundation with underground braces made of triangular members according to the present invention, and FIG. 4 is a partial cross-sectional view of the constructed pile foundation with underground braces. Fifth
6 are side views of a pile foundation with underground braces made of triangular members showing another embodiment of the present invention. 1... Foundation pile, 2... Triangular member, 3
...Underground brace, 4...Joint part, 5
...Engagement part, 6... Opening hole, 7...
Reinforcement rib, 8... Filler, 9... Bolt/nut, 10... Underground beam, 11... Footing, 12... Shear connector .

Claims (1)

[Claims] 1. In a pile foundation with underground braces, in which foundation piles are installed in the ground at appropriate intervals, and underground braces are integrally installed between the foundation piles, the underground braces are arranged in a plurality of triangular pieces. The triangular member is composed of a plurality of members, and the triangular member engages with a joint provided on the side portion of the foundation pile, and integrally connects the foundation piles with an underground beam. A pile foundation with underground braces.