CN102235017B - Lateral force resisting method for soft soil foundation building - Google Patents

Abstract

The method for building on soft soil foundation to resist lateral force is to complete the construction of the building and its foundation on straight piles, and the vertical gravity load of the building and its foundation is borne by the straight piles. On the outside of the building, the inclined piles are symmetrically driven obliquely under the foundation under the building. The top of the inclined piles is set on one side of the outer contour of the building, and the bottom is set on the other side of the outer contour of the building, and the top of the inclined piles is connected to the foundation. . The method for resisting lateral force of a building on soft soil foundation of the present invention can effectively improve the ability of the building to withstand lateral action and load by setting inclined piles; in addition, the present invention can be used for newly-built buildings, and can also be used for reinforcing existing buildings thing.

Description

Method of Resisting Lateral Force of Buildings on Soft Soil Foundation

technical field

The invention relates to geotechnical engineering and construction engineering, in particular to a method for resisting building lateral force in soft soil foundation building pile foundation engineering.

Background technique

Soft soil foundations are generally set with weak soil layers with low strength and high compressibility. Buildings are constructed on soft soil foundations. If the soft soil foundation is not treated, foundation instability or excessive subsidence will often occur, resulting in buildings being damaged or unable to Normal use.

In the existing technology for soft soil foundation treatment, as disclosed in Chinese Patent Application No. CN200710068309.4, "A Method for Implanting Prefabricated Reinforced Concrete Anti-Lateral Force Pile with Cement Mixed Soil Curtain", it adopts the method of first using cement at the construction site. The mixer is placed along the depth of the pile body, depending on the soil quality and soil compaction, the whole process of mixing the soil or part of the upper water-stop curtain to form a curtain, and then the pile driver is used to implant the pile body to form a soil-retaining water-stop enclosure wall. Among them, the pile body adopts reinforced concrete prefabricated T-shaped / I-shaped piles, and because of the use of strong soil mixing or drilling rigs for grouting, it is suitable for various types of soil enclosure projects in principle.

Also as Chinese Patent No. CN99237125.2 discloses "a hammering device for driving soil anchors, inclined piles, and buried pipes without excavation", this patented technology is used in the geotechnical engineering of industry and civil buildings in civil engineering A hammering device for soil anchors, inclined piles, and buried pipes without excavation. This device is composed of a machine base, a tower, a hoist, an impact hammer, and a guide rail. It can be rotated at any inclination angle between 0 and 90°. There are four bearing wheels welded under the impact hammer. The impact hammer is placed on the guide rail, pulled and loosened by the hoist, and can freely roll up and down the guide rail to impact the steel pipe. The steel pipes are driven into the soil according to different angles. The equipment of this device is light and handy, and can be constructed with height changes. It can enter narrow sites, hills, and underwater constructions. It can be constructed without pollution, vibration, and noise.

In addition, Chinese Patent No. CN97235911.7 discloses "a kind of permeable breakwater pile foundation", which includes structural units and beams connecting structural units. At least two rows of structural units are distributed in front and rear, and the structural units are composed of at least three or less The utility model is composed of an inclined pile group composed of single piles with one end embedded in the seabed, inclined in different directions, and a pile cap located on the upper part of the single pile to fix the upper ends of the said inclined pile group into one body. Compared with the prior art, the utility model has the advantages of increasing the horizontal bearing capacity by more than four times per linear meter of dike length under the condition that the sectional area of pile foundation is the same per linear meter of embankment length.

Chinese patent application number CN92102906.3 relates to the treatment method of dangerous buildings in the construction field. When the foundation subsidence or uneven subsidence causes shear damage to the foundation and the edge of the foundation, which affects normal use, add inclined piles to various parts of the foundation. If If the subsidence is not uniform, first open a trench on the side with more uplift of the foundation to correct the building to the normal position, pour the pile material, and add inclined piles on the side with less uplift (or subsidence), and the side with more uplift Less inclined piles are added, and the groove position, inclined pile angle, length, and number are obtained according to the theory of plasticity, and the settlement and settlement difference of each part of the foundation are controlled within a certain allowable range, so that dangerous buildings can be built again. Normal use.

Although in the above-mentioned patented technology, inclined piles are used to deal with dangerous buildings at various parts of the foundation, in addition bridges and docks and other buildings often adopt the method of setting inclined piles to resist lateral force, these methods of setting inclined piles cannot be used for the following reasons Widely used in industrial and civil buildings:

(1) Due to the downward settlement of the building under the normal gravity load, in addition to being subjected to pressure and shear, the top of the inclined pile also undergoes bending deformation, which is easily damaged due to complex stress and insufficient strength.

(2) Setting inclined piles usually includes inclined piles to the outside of the building, and the inclined piles may exceed the permitted plane range and depth range of the building.

(3) Install inclined piles to the inside of the building. Under the normal gravity load of the building, the foundation between the inclined piles on both sides will generate a large tensile stress and crack and fail.

Contents of the invention

The object of the present invention provides a kind of method that the building of soft soil foundation resists lateral force, by arranging inclined pile, can effectively improve the ability of building to bear lateral action and load; This method can be used for new building, also can be used for Fortify existing buildings.

For achieving the above object, technical scheme of the present invention is:

The method for building on soft soil foundation to resist lateral force is to complete the construction of the building and its foundation on straight piles, and the vertical gravity load of the building and its foundation is borne by the straight piles. On the outside of the building, the inclined piles are symmetrically driven obliquely under the foundation under the building. The top of the inclined piles is set on one side of the outer contour of the building, and the bottom is set on the other side of the outer contour of the building, and the top of the inclined piles is connected to the foundation. .

Further, the method for resisting lateral force of the soft ground building of the present invention comprises the following steps:

1) At the location of the new building, construct straight piles and symmetrical obliquely driven inclined piles first; the top of the inclined piles is set on one side of the outer contour of the building, and the bottom is set on the other side of the outer contour of the building;

2) Construct the building foundation on the straight pile, the inclined pile is disconnected from the building foundation, and the settlement height is reserved;

3) Construction of buildings on building foundations;

4) After the construction of the building is completed and the settlement is stable, connect the top of the inclined pile to the foundation of the building.

Again, the method for resisting lateral force of the soft ground building of the present invention is characterized in that it comprises the following steps:

1. The building foundation and the straight piles under it have been set up under the built building;

2. After the construction of the building is completed on the foundation of the building and the settlement is stable, the inclined piles are symmetrically driven obliquely under the foundation of the building. The top of the inclined pile is set on the side of the outer contour of the building, and the bottom is set The other side of the building outline.

In addition, the form of the building foundation is strip shape, or raft shape, or box shape.

The inclined pile adopts a pile whose unit cross-sectional area tensile strength is greater than 5MPa.

Inwardly inclined piles are added to the foundation of buildings on soft soil foundation to resist lateral force. The top of the inclined pile can withstand both compression and tension. Under the vertical load of the building, the tensile stress of the foundation between the inwardly inclined piles on both sides of the building can be controlled within the allowable range of strength; the inclined piles are mainly subjected to the axial force caused by the lateral load, and the building is The shear and bending internal force at the top of the inclined pile caused by the settlement under the gravity load can be controlled within the allowable range of strength.

Beneficial effects of the present invention

1. The present invention can effectively improve the ability of buildings to withstand lateral actions and loads by setting inclined piles, including lateral seismic actions, lateral earth pressure, wind loads, blast loads, and impact effects.

2. The inclined piles can be arranged symmetrically, so as to avoid the local eccentric load of the building.

3. The present invention can be used for newly-built buildings, and can also be used for reinforcing existing buildings.

4. The vertical gravity load of the building and the foundation is borne by the straight pile. After the settlement is stable, the top of the inwardly inclined pile is connected to the foundation. The inclined pile is mainly subjected to the axial force caused by the lateral load, which is caused by the settlement of the building. The shear and bending internal forces at the top of the inclined pile can be controlled within the allowable range of strength.

5. Due to the vertical gravity load, the foundation tensile stress between the inwardly inclined piles on both sides of the building can be controlled within the allowable range of strength, so it will not crack.

Description of drawings

Fig. 1 sets up the schematic diagram of the building of inclined pile for the present invention;

Fig. 2a～Fig. 2c are the schematic diagrams of an embodiment of the present invention namely newly-built buildings add inclined pile;

3a to 3c are schematic diagrams of another embodiment of the present invention, that is, adding inclined piles to existing buildings.

Detailed ways

The present invention will be further described below in conjunction with embodiment.

Referring to Fig. 1, the method for the soft ground building of the present invention to resist lateral force, construction completes building 2 and foundation 3 thereof on straight pile 1, the vertical gravity load of building 1 and foundation 3 thereof is borne by straight pile 1 After the building construction is completed and the settlement is stable, the inclined piles 4 and 5 are symmetrically driven obliquely from the outside of the building 2 to the bottom of the foundation 3 under the building 2, and the tops of the inclined piles 4 and 5 are arranged on the outer contour of the building 2 side, the bottom of which is set on the other side of the outer contour of the building 2, and the top of the inclined pile is connected to the foundation 3.

After the building construction is completed and the settlement is stable, add inward inclined piles under the building, so that the inclined piles are set within the permitted plane range and depth range of the building. Under the action of the vertical gravity load of the building, the building foundation and the inclined piles The unfavorable internal force generated at the top can be controlled within the allowable range, and the lateral force of the building is resisted by the inclined piles.

Example 1

Referring to Fig. 2a～Fig. 2c, the method of the present invention is used for adding inclined piles to new buildings.

1) Construct the straight pile 1 and the inclined pile 4, 5 with a depth of about 30m at the position of the new building 2 with a width of about 10m;

2) The top of the inclined piles 4 and 5 is arranged on one side of the outer contour of the building 2, and the bottom thereof is arranged on the other side of the outer contour of the building 2, so that the inclined piles 4 and 5 can be arranged within the permitted building plane range; 4.5 Steel pipe members poured into concrete are used, the top of which can withstand both pressure and tension, and the tensile strength per unit cross-sectional area is greater than 5Mpa;

3) Build the building foundation 3 on the straight pile 1, the form of the building foundation 3 can be strip shape, raft shape or box shape; the inclined piles 4, 5 are disconnected from the building foundation 3, and the settlement height is reserved ;

4) building a building 2 on the building foundation 3;

5) After the construction of the building 2 is completed and the settlement is stable, the tops of the inclined piles 4 and 5 are connected to the foundation 3 .

Example 2

Referring to Fig. 3a to Fig. 3c, the method of the present invention is used for adding inclined piles to existing buildings.

1) Under the built building 2 with a width of about 10m, a building foundation 3 and a straight pile 1 with a depth of about 30m are arranged, and the form of the foundation 3 can be strip-shaped, raft-shaped or box-shaped;

2) After the construction of the building 2 is completed and the settlement is stable, the inclined piles 4 and 5 with a depth of about 30m are sunk under the building foundation 3;

3) The top of the inclined piles 4 and 5 is arranged on one side of the outer contour of the building 2, and the bottom thereof is arranged on the other side of the outer contour of the building 2, so that the inclined piles 4 and 5 can be arranged within the permitted building plane range; 4.5 Steel pipe members poured into concrete are used, the top of which can withstand both pressure and tension;

4) The tops of the inclined piles 4 and 5 are connected to the building foundation 3;

The invention can be popularized and applied in construction engineering and pile foundation engineering in soft soil areas, and can effectively improve the ability of buildings to bear lateral action and load.

Claims (7)

1. the method for soft soil foundation building lateral force resisting, building and basis thereof are completed in construction in straight stake, the vertical gravity load on building and basis thereof is subjected to by straight pile, until building construction complete and settlement stability after, below, basis symmetrical inclined under the building of building lateral is to squeezing into taper pile again, the taper pile top is arranged on building outline one side, and its bottom is arranged on building outline opposite side, and the taper pile top is connected with basic.

2. the method for soft soil foundation building lateral force resisting, is characterized in that, comprises the steps:

1) first construct at the new building object location and straight stake and symmetrical inclined are set to squeezing into taper pile; The taper pile top is arranged on building outline one side, and its bottom is arranged on building outline opposite side;

2) construction building thing basis in straight stake, taper pile and building foundation disconnect, and reserve settling height;

3) construction building thing on the building foundation;

4) architecture construction complete and settlement stability after, then the top of taper pile is connected with the building foundation.

3. the method for soft soil foundation building lateral force resisting as claimed in claim 2, is characterized in that,

Described taper pile adopts unit cross-sectional area tensile strength greater than the stake of 5MPa.

4. the method for soft soil foundation building lateral force resisting as claimed in claim 2, is characterized in that,

The form of described building foundation is bar shaped or raft plate shape or box-shaped.

5. the method for soft soil foundation building lateral force resisting, is characterized in that, comprises the steps:

1) be provided with under the built construction thing building foundation and under straight stake;

2) after settlement stability, then under the built construction beyond the region of objective existence side direction building foundation symmetrical inclined to squeezing into

Taper pile, taper pile top are arranged on building outline one side, and its bottom arranges outside the building

The profile opposite side, and the taper pile top is connected with the building foundation.

6. the method for soft soil foundation building lateral force resisting as claimed in claim 5, is characterized in that,

Described taper pile adopts unit cross-sectional area tensile strength greater than the stake of 5MPa.

7. the method for soft soil foundation building lateral force resisting as claimed in claim 5, is characterized in that,

The form of described building foundation is bar shaped or raft plate shape, or box-shaped.

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