JPH0565716A - Steel pipe base - Google Patents

Abstract

PURPOSE:To obtain sufficient bearing strength even by soft ground and to make construction work easier even in narrow areas by a method in which steel piles having spiral blades set discontinuously on its periphery are set in parallel and the heads of them are connected. CONSTITUTION:Spiral blades 3 are discontinuously formed at intervals 1S of 0.5 m or longer on the periphery of steel piles 1 of an outside diameter, of 50 mm or longer. The steel piles 1 are set in parallel and the heads of them are connected by a connector 2, The piles 1 can thus be easily carried in narrow spree areas and can also be easily driven by a simplified rotary torque device by the forces of wrench and others.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel pile foundation suitable for a foundation such as a low-rise house or a small-scale building and used for a ground having a soft ground layer.

[0002]

In recent years, there have been many cases where structures are built on ultra-soft ground, which has not been seen in the past due to the impact of soaring land prices. The ground has been improved by cement injection etc. within a few US depths, but in many cases there are no measures to deal with and complaints about housing damage due to land subsidence are constant. Moreover, the cost for ground improvement was high, and the environmental impact due to soil discharge, noise, etc. was not small.

Particularly in densely populated areas, it is difficult to carry in and out equipment and materials, and the impact on the environment is a serious problem. Moreover, there is no basic construction method that solves these problems and is suitable for small-scale buildings.

For example, in the case of a small-scale building, it is sufficient that each pile has a proof stress of 5 to 15 tons, but conventionally such a pile is not found. Piling with the hammering method is not allowed in dense residential areas. The method of digging holes and injecting cement milk causes slurry pollution.

The present invention has been made in view of the above problems. Its purpose is to make it easy to carry in and out of equipment materials even in a congested residential area, and it can be built without generating soil, noise, or discharge of cement slurry, and even on soft ground. The purpose is to propose a steel pile foundation that exhibits sufficient bearing capacity as a foundation for a large-scale building.

[0006]

The present invention has an "outer diameter of 50 m.
A steel pile foundation in which a plurality of steel piles with spiral winglets discontinuously installed at intervals of 0.5 m or more on the outer periphery are built in parallel and the heads of the piles are connected by a connecting material ". is there.

[0007]

[Operation] In the steel pile used for the steel pile foundation, the supporting force of soil acts on one surface of the wing, and the soil that has been consolidated further adheres, and the frictional force is added to the steel pile to provide a large supporting force. Therefore, a steel pile foundation constructed by arranging a plurality of steel piles in parallel and connecting the pile heads is required for a small-scale building foundation even if the steel pile has a relatively small diameter. A proof stress of 15 tons can be expressed on soft ground.

The steel pile may have a relatively small diameter, and since it has a spiral wing piece on the outer circumference, a simple rotary torque device or a wrench is used to generate vibration noise and the like by human power, and it is easy and short It can be installed by screwing into the ground. Also, since the winglets are discontinuous, no sediment discharge occurs. The equipment and materials are lightweight and can be carried into a narrow urban area.

The steel pile used in the present invention has an insufficient supporting force when the pile diameter is less than 50 mm, and becomes heavy when it has a pile diameter of 200 mm or more, which is unsuitable because the torque required for construction is large. The winglet has a diameter of 1.5 to 2.5 times the pile diameter and 1-2.
When the winding is used as a unit, the building torque does not become excessive and the bearing capacity of the soil can be obtained, which is preferable.

[0010]

EXAMPLE A steel pile foundation shown in FIG. 1 is constructed by arranging two steel piles 1 and 1 in close proximity to each other and connecting the pile heads with a connecting member 2.
Two steel piles were made to function as one steel pile foundation. The steel stake 1 is provided with discontinuous spiral wing pieces 3 around the outer circumference, the diameter of the wing pieces 3 is twice the pile diameter, and the distance between the wing pieces 3 is 50 cm or more.

Although not shown, it is possible to construct two or more steel piles by arranging them in parallel as in FIG. 1 and connecting the pile heads with a connecting material to use as one pile. it can.

[0012]

The present invention has the following effects.

Even with soft ground, a steel pile having a relatively small diameter can be used to develop a bearing capacity of 5 to 15 tons required for a small-scale building.

Even in a narrow urban area, the environment is not damaged, work efficiency is high, and construction can be performed in a short period of time.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a steel pile foundation according to an embodiment.

[Explanation of symbols]

 1 ... Steel pile, 2 ... Connection material, 3 ... Wing piece

Claims (1)

[Claims] 1. A plurality of steel piles having an outer diameter of 50 mm or more and spiral winglets on the outer periphery provided discontinuously at intervals of 0.5 m or more are laid in parallel, and the pile heads are connected by a connecting material. Steel pile foundation characterized by being made.