Lifting debris flow blocking structure and construction method

Abstract

According to the liftable debris flow blocking structure and the construction method, a raft foundation with a pile core is built in a debris flow gully in a region with a relatively smooth longitudinal slope in the debris flow flowing direction, the pile core is sleeved with a movable steel pipe shell, the steel pipe shell and a pile core cavity are filled with coarse sand, and the steel pipe shell hoops waste tires; the movable steel pipe shells are connected into a whole through the tops of the movable steel pipe shells through connecting beams, a debris flow pile forest structure capable of buffering collision and being integrally stressed is formed, after debris flow occurs and silt is deposited in front of the blocking dam to form a full silt dam, the connecting beams are continuously stretched upwards to enable the bottoms of the movable steel pipe shells to reach the tops of the pile cores, and then concrete is poured into the movable steel pipes. And after the concrete is solidified, reinforced concrete grids are poured at the contact positions of the movable steel pipes and the triangular pile cores, so that a shell of the movable steel pipes poured with the concrete forms a two-layer pile forest and an overflowed raft foundation, the triangular pile cores and the grids form a two-layer debris flow pile forest structure, and debris flow continues to be blocked.

Description

Technical Field

[0001] The invention relates to a debris flow blocking structure, and in particular to a liftable debris flow blocking structure and a construction method which are particularly suitable for gully areas where small and medium-scale debris flow disasters occur repeatedly. Background Art

[0002] Debris flow is a multiphase fluid with strong impact force composed of water, soil, sand and stone, which has the characteristics of strong destructiveness and rapid flow rate. In recent years, with global warming, the frequency and impact of extreme weather events have become increasingly serious. Debris flow disasters caused by extreme heavy rainfall are extremely common in the western region with fragile ecology, which always threatens people's lives and property safety, poses serious challenges to the normal operation of roads and railways, and affects the stable development of local economy and society. The prevention and control of debris flow is an important part of my country's disaster prevention and mitigation projects. Its overall idea usually starts from multiple angles such as source consolidation, interception, drainage and early warning and forecasting to form comprehensive prevention measures. It not only weakens the source of debris flow materials through biological measures or protective engineering, drains the precipitation that induces debris flow, builds blocking structures in debris flow ditches, reduces the speed and destructive power of debris flow, but also relocates and evacuates residents and important buildings on the debris flow impact path. However, no matter how it is managed, debris flow gullies are the main diversion channels for the movement of debris flow. The source area of ​​debris flow materials is difficult to be effectively managed in a short period of time, and debris flow disasters of varying scales may occur repeatedly in the same area.

[0003] At present, in order to reduce the impact damage after the formation of debris flow, usually in the upstream area of ​​the debris flow, narrow channels and flat areas in the reservoir are selected to build intercepting structures, intercepting the silt, rocks, etc. carried by debris flows of different sizes, adjusting the longitudinal ratio of the debris flow gully, reducing the impact damage to the downstream, and ensuring the normal use of the downstream drainage system. For debris flow intercepting structures with small mouths and large bellies, it usually takes several years to become a full silt dam. For the upstream, the measures of closing mountains and afforestation are adopted to consolidate the topsoil. The time for consolidation of soil and water conservation is relatively short. Debris flow may still occur in the later period. At this time, the full dam can no longer serve the purpose of intercepting sand and stone. If a new dam is selected at another site, it will be time-consuming and laborious. The existing debris flow has the shortcomings of limited initial height of the intercepting structure, easy overflow, slow consolidation and drainage speed, etc. Therefore, there is an urgent need for a debris flow intercepting structure, which can continue to play the role of the intercepting structure after the initial height intercepting structure is full, and accelerate the consolidation and drainage of the storage field after simple construction treatment. Summary of the invention

[0004] The present invention organically combines the self-lifting technology with the debris flow barrier structure, and proposes a liftable debris flow barrier structure and a construction method that can raise the dam height after meeting the requirements. It can block debris flows multiple times without increasing the size of the barrier structure, thereby increasing the storage capacity of the debris flow barrier dam.

[0005] To achieve the above-mentioned purpose, the liftable debris flow blocking structure of the present invention comprises a raft foundation cast on the bedrock in the narrow area of ​​the debris flow flow direction on the debris flow ditch and a plurality of reinforced concrete pile cores embedded in the raft foundation, a movable steel pipe shell is sleeved on the outside of each pile core, and the upper ends of the plurality of movable steel pipe shells are connected by connecting beams to form a debris flow pile forest structure that can buffer collisions and intercept debris flows as a whole. After the silt in the debris flow accumulates and fills the dam, the connecting beam is stretched upward to make the bottom of the movable steel pipe shell reach the top of the pile core, concrete is cast in the movable steel pipe shell, and after the concrete is completely solidified, a reinforced concrete grille is cast at the contact position between the movable steel pipe shell and the pile core, so that the movable steel pipe shell cast with concrete forms a new pile forest and the raft foundation covered with silt, the pile core and the grille form a two-layer debris flow pile forest structure as a whole.

[0006] The plurality of pile cores are embedded in the raft foundation in a plum blossom shape.

[0007] The pile core is a triangular structure, and the cavity between the movable steel pipe shell and the pile core of the triangular structure is filled with coarse sand in layers.

[0008] The outer hoop of the steel pipe shell is provided with waste tires.

[0009] The construction method of the liftable debris flow blocking structure of the present invention comprises the following steps:

[0010] 1) Excavate the foundation to the bedrock layer in the narrow area of ​​the upstream channel of the debris flow ditch in the direction of the debris flow, and cast the raft foundation on the bedrock layer;

[0011] 2) embedding a number of triangular pile cores of reinforced concrete structure distributed in a plum blossom shape on the raft foundation;

[0012] 3) A movable steel pipe shell is sleeved outside each triangular pile core, and coarse sand is filled in layers in the cavities of the movable steel pipe shell and the triangular pile core. The upper ends of several movable steel pipe shells are connected by connecting beams to form a debris flow pile forest structure that can buffer collisions and bear overall stress;

[0013] 4) When a debris flow occurs, after the silt in front of the pile forest accumulates and fills the dam, the movable steel tube shell is continuously stretched upwards through the connecting beam. When the bottom of the movable steel tube shell reaches the top of the pile core, concrete is poured in the movable steel tube shell. After the concrete solidifies, a reinforced concrete grid is poured at the contact position between the movable steel tube shell and the triangular pile core, so that the new pile forest formed by the movable steel tube shell poured with concrete, the raft foundation covered with silt, the triangular pile core and the grid form a two-layer debris flow pile forest structure as a whole, which continues to block the debris flow.

[0014] The present invention forms a debris flow pile forest structure capable of buffering collision and bearing overall force by sleeve-connecting a movable steel pipe shell on the pile core of a raft foundation and connecting the movable steel pipe as a whole through a connecting beam. When a debris flow occurs and silt accumulates to fill the dam, the bottom of the movable steel pipe is continuously stretched upward by the connecting beam to make it reach the top of the pile core. Then concrete is poured in the movable steel pipe. After the concrete is completely solidified, a reinforced concrete grid is poured at the contact position between the movable steel pipe and the triangular pile core, so that a new pile forest formed by the movable steel pipe with concrete, the raft foundation covered with silt, the triangular pile core and the grid form a two-layer debris flow pile forest structure as a whole, and continue to block the debris flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of a foundation layer formed by a raft foundation, a triangular pile core, a movable steel pipe shell, waste tires, a connecting beam and coarse sand of the present invention;

[0016] Figure 2 It is a schematic diagram of the overall structure of the present invention which forms a two-layer pile forest after being lifted.

[0017] Figure 3 It is a cross-sectional view of the debris flow ditch, the debris flow direction and the pile forest of the foundation layer when it is not lifted;

[0018] Figure 4 This is a cross-sectional view of the two-layer pile forest structure formed by the rear debris flow ditch, the debris flow flow direction and the lifting

[0019] In the figure: 1, raft foundation; 2, triangular pile core; 3, steel pipe shell; 4, connecting beam; 5, grille; 6, coarse sand; 7, concrete; 8, debris flow ditch; 9, debris flow direction; 10, silt; 11, waste tires.

[0020] The structural principle and construction method of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0021] See also Figure 1 and Figure 3The present invention comprises a raft foundation 1 cast on the bedrock in a narrow area of ​​a debris flow direction 9 on a debris flow ditch 8 and a plurality of reinforced concrete pile cores 2 embedded in the raft foundation 1, a movable steel pipe shell 3 is sleeved on the outside of each pile core 2, the steel pipe shell 3 and the pile core 2 cavity are filled with coarse sand 6, the movable steel pipe shell 3 is sleeved with a waste tire 11, and the upper ends of the plurality of movable steel pipe shells 3 are connected by a connecting beam 4 to form a debris flow pile forest structure capable of buffering collision and bearing overall force to intercept debris flow, see Figure 2 and Figure 4 After the silt 10 in the debris flow accumulates and fills the dam, the bottom of the movable steel pipe shell 3 is stretched upward by the connecting beam 4 to make the top of the pile core 2, and concrete 7 is poured in the movable steel pipe shell 3. After the concrete 7 is solidified, a reinforced concrete grid 5 is poured at the contact position between the movable steel pipe shell 3 and the pile core 2, so that the movable steel pipe shell 3 with the concrete 7 poured forms a new pile forest and the raft foundation 1 covered with silt 10, the pile core 2 and the grid 5 form a two-layer debris flow pile forest structure as a whole.

[0022] See also Figure 1 , 2, 3, 4, the construction method of the present invention comprises the following steps:

[0023] 1) excavating the foundation to the bedrock layer in the narrow area of ​​the upstream channel of the debris flow ditch 8 in the debris flow direction 9, and pouring the raft foundation 1 on the bedrock layer;

[0024] 2) embedding a number of triangular pile cores 2 of reinforced concrete structure distributed in a plum blossom shape on the raft foundation 1;

[0025] 3) A movable steel tube shell 3 is sleeved outside each triangular pile core 2, and coarse sand 6 is filled layer by layer in the cavities of the movable steel tube shell 3 and the triangular pile core 2. The upper ends of several movable steel tube shells 3 are connected by connecting beams 4 to form a debris flow pile forest structure that can buffer collisions and bear overall stress;

[0026] 4) When a debris flow occurs, after the silt 10 accumulates in front of the pile forest and fills the dam, the connecting beam 4 is continuously stretched upward to make the bottom of the movable steel pipe shell 3 reach the top of the pile core 2, and concrete 7 is poured in the movable steel pipe 3. After the concrete solidifies, a reinforced concrete grid 5 is poured at the contact position between the movable steel pipe shell 3 and the triangular pile core 2, so that the new pile forest formed by the movable steel pipe shell 3 poured with concrete, the raft foundation 1 covered with silt 10, the triangular pile core 2 and the grid 5 as a whole form a two-layer debris flow pile forest structure to continue to block the debris flow.

Claims

1. The liftable debris flow barrier structure is characterized by: The invention comprises a raft foundation (1) cast on the bedrock in a narrow area of ​​the debris flow direction (9) on a debris flow ditch (8) and a plurality of reinforced concrete pile cores (2) embedded in the raft foundation (1). A movable steel pipe shell (3) is sleeved outside each pile core (2). The upper ends of the plurality of movable steel pipe shells (3) are connected by a connecting beam (4) to form a debris flow pile forest structure capable of buffering collision and intercepting debris flow as a whole. When the silt (10) in the debris flow accumulates and fills the dam, the connecting beam (4) is used to connect the movable steel pipe shells (3) to the pile forest structure. The beam (4) is stretched upward so that the bottom of the movable steel tube shell (3) reaches the top of the pile core (2), and concrete (7) is poured in the movable steel tube shell (3). After the concrete (7) is completely solidified, a reinforced concrete grid (5) is poured at the contact position between the movable steel tube shell (3) and the pile core (2), so that the movable steel tube shell (3) with the poured concrete (7) forms a new pile forest, and the raft foundation (1) covered with silt (10), the pile core (2) and the grid (5) form a two-layer debris flow pile forest structure as a whole.

2. The liftable debris flow barrier structure according to claim 1 is characterized in that: The plurality of pile cores (2) are embedded in a plum blossom shape on the raft foundation (1).

3. The liftable debris flow barrier structure according to claim 1 is characterized in that: The pile core (2) is a triangular structure, and the cavity between the movable steel pipe shell (3) and the pile core (2) of the triangular structure is filled with coarse sand (6) in layers.

4. The liftable debris flow barrier structure according to claim 1 is characterized in that: The outer hoop of the steel pipe shell (3) is provided with a waste tire (11).

5. A construction method of a liftable debris flow barrier structure according to any one of claims 1 to 4, characterized in that: 1) excavating a foundation to a bedrock layer in a narrow channel area upstream of a debris flow channel (8) in a debris flow direction (9), and pouring a raft foundation (1) on the bedrock layer; 2) embedding a plurality of triangular pile cores (2) of reinforced concrete structure distributed in a plum blossom shape on the raft foundation (1); 3) A movable steel tube shell (3) is sleeved outside each triangular pile core (2), coarse sand (6) is filled in layers in the cavities of the movable steel tube shell (3) and the triangular pile core (2), and the upper ends of several movable steel tube shells (3) are connected by a connecting beam (4) to form a debris flow pile forest structure capable of buffering collision and bearing overall force; 4) When a debris flow occurs, the silt (10) in front of the pile forest accumulates and fills the dam. The movable steel tube shell (3) is continuously stretched upward by the connecting beam (4). When the bottom of the movable steel tube shell (3) reaches the top of the pile core (2), concrete (7) is poured in the movable steel tube shell (3). After the concrete solidifies, a reinforced concrete grid (5) is poured at the contact position between the movable steel tube shell (3) and the triangular pile core (2). The new pile forest formed by the movable steel tube shell (3) poured with concrete, the raft foundation (1) covered with silt (10), the triangular pile core (2) and the grid (5) form a two-layer debris flow pile forest structure as a whole, and continue to block the debris flow.

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