JPH05331865A - Differential settlement reducing method of multistory building - Google Patents

Abstract

PURPOSE:To eliminate the effect of differential settlement on a structure by bringing it into settlement at the initial period of the execution of work. CONSTITUTION:A ground surrounded by a land slide protection cut-off wall 1 reaching to an impermeable layer is excavated, and the ground-water is pumped up from the ground 4 lower than a pit excavation bottom so as to reduce the ground-water pressure. While a batholith 6 provided temporarily or regularly to a flooring surface is constructed, the steel frame of the structure is built to reach up to the ground surface. Then, after a heavy substance 8 such as earth and sand, or water is thrown in to the evacuated space, so as to add the burden to the ground 4 lower than the batholith 6, the steel frame construction of the structure, and other constructions are carried out while pumping up the ground-water from the ground 4, and the weight of the heavy substance 8 corresponding to the increase of the weight owing to such a construction is exhausted. After exhausting all the heavy substance 8, the ground-water level of the ground 4 is restored corresponding to the increased weight by the construction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for reducing uneven settlement by causing early settlement when constructing heavy structures such as skyscrapers.

[0002]

2. Description of the Related Art Conventionally, heavy structures such as skyscrapers are
It is constructed so that the diluvial sand layer is used as the foundation ground and supported by it. As described above, diluvial sand layers are generally reliable as foundation ground, but even in such cases, uneven settlement due to immediate settlement is a problem, and in order to avoid obstacles due to this, concrete should be placed in the problem area. I was hitting after.

[0003]

However, the above-mentioned method of post-casting concrete makes the construction of the basement part troublesome, and is difficult to predict especially in the construction of a super-high-rise building with a large weight. The differential settlement has a great influence on the design and construction.

In view of the above circumstances, it is an object of the present invention to eliminate the influence of differential settlement on a structure by creating settlement in the early stage of construction.

[0005]

The present invention has been made in consideration of the above-mentioned problems, and excavates the ground surrounded by mountain retaining water-blocking walls whose lower end reaches an impermeable layer, and it is located below the root cutting bottom. The groundwater is pumped up from the ground to lower the groundwater pressure, and a temporary or permanent bottom is constructed on the floor surface, and the structure is steel-framed so that it reaches the ground, and earth and sand and water are added to the excavation space. After loading a load such as the above to the ground part, applying a load to the ground below the bottom, then constructing a steel frame and other construction of the structure while pumping groundwater from the ground below the bottom, After discharging the load of weight corresponding to the increased load due to construction, after discharging all of the load,
It is intended to solve the above problems by providing a method for reducing the differential settlement of a structure, which is characterized by restoring the groundwater level of the ground beneath the bottom according to the increased load due to construction.

[0006]

In the present invention, by loading a load on the ground where the groundwater is pumped and the water pressure is reduced,
Subsidence occurs (preloading). Then, by discharging a load having a weight corresponding to the increased load due to the steel frame construction of the structure, the construction can be proceeded in a state where the load and the ground pressure are balanced.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail based on an embodiment shown in FIGS. As shown in FIG. 1, when excavating the ground, first, the earth retaining water stop wall 1 is formed so that its lower end reaches the impermeable layer 2, and then the earth enclosed by this earth retaining water stop wall 1 is a structure. Depth of the bottom of the 3
The groundwater pressure is reduced by excavating the groundwater and pumping groundwater from the ground 4 below the root cutting bottom. Groundwater is pumped by deep well. Reference numeral 5 is an anchor, which is unnecessary when the mountain retaining water blocking wall 1 is formed in a circular shape.

Next, as shown in FIG. 2, a temporary or permanent bottom plate 6 is constructed on the flooring surface, and a steel frame erection (main construction) 7 of the structure is carried out so as to reach the above-ground portion. Also at this time, groundwater is pumped from the ground 4 by the deep well to reduce the groundwater pressure.

After this, subsidence is caused as shown in FIG. That is, a load 8 made of water is put into the excavation space up to the ground portion, and a load is applied to the ground 4 to cause subsidence (preloading). In this case, the load 8 can use not only water but also earth and sand.

After the settlement is completed and stabilized, steel erection above the structure and steel erection of the basement (such as erection of steel beams) are carried out. Groundwater is supplied from the ground 4 by the deep well. Steel structure erection 9 of the structure is performed while pumping water, and weight 8 corresponding to the increased load due to the construction
Is discharged.

When all the loads 8 have been discharged, the groundwater level of the ground 4 is restored in accordance with the increased load due to construction. After that, the normal construction work is continued on the stable ground 4.

[0012]

As described above, according to the present invention, the ground surrounded by the earth retaining water blocking wall whose lower end reaches the impermeable layer is excavated, and ground water is pumped from the ground below the root cutting bottom. To reduce the groundwater pressure, construct a temporary or permanent bottom plate on the floor surface, and construct a steel frame for the structure to reach the ground part, and load loads such as earth and sand into the excavation space above the ground part. After applying the load to the ground below the bottom, the structure of the structure and other construction of the structure is performed while pumping groundwater from the ground below the bottom, and the increased load due to the construction is supported. Discharge the load of the weight to
After discharging all the load, the groundwater level of the ground below the bottom is restored according to the increased load due to construction. In this way, since the load is applied to the ground and pumping from the ground causes subsidence in advance,
The ground after the subsidence becomes stable, and the differential subsidence is suppressed so that the construction of the structure is not hindered, which is an effect of excellent practicality.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a step of excavating the ground in an embodiment of the method for reducing uneven settlement of a structure according to the present invention.

FIG. 2 is an explanatory diagram showing a stage in which a bottom plate is constructed and a steel frame is erected for permanent installation.

FIG. 3 is an explanatory view showing a stage where a load is loaded.

FIG. 4 is an explanatory view showing a stage of discharging a load corresponding to the increment due to the steel frame construction.

FIG. 5 is an explanatory diagram showing a stage where a load is discharged.

[Explanation of symbols]

 1 ... Mountain retaining water barrier 2 ... Impermeable layer 4 ... Ground 6 ... Bottom 8 ... Load

Claims (1)

[Claims] 1. The ground surrounded by a mountain retaining water stop wall that reaches the impermeable layer at its lower end is excavated, groundwater is pumped from the ground below the root cutting bottom to reduce the groundwater pressure, and temporary installation on the floor surface or While constructing the bottom of the main building,
The structure is erected so that it reaches the ground, and the load such as earth and sand and water is put into the excavation space to the ground to apply the load to the ground below the bottom, and then load the ground below the bottom. While constructing a steel frame structure and other construction of the structure while pumping groundwater from the ground, discharge the load of the weight corresponding to the increased load due to the construction, discharge all the load, and then increase by the construction A method for reducing the differential settlement of a structure, which comprises restoring the groundwater level of the ground beneath the bottom according to the load.