CN117780379A - Damping energy-consumption tunnel portal under condition of limited space in strong earthquake area and construction method - Google Patents

Abstract

The invention discloses a shock-absorbing energy-consuming cave door and a construction method under limited space conditions in a strong earthquake area. The shock-absorbing energy-consuming cave door consists of a number of limited shock-absorbing energy-consuming pipes passing through the end wall of the cave door and the drainage layer behind the wall. , and then extends into the rock and soil mass; the main body of the limit shock-absorbing energy-dissipating pipe is an expanded steel pipe and a concrete anchor at the end of the expanded steel pipe. The expanded steel pipe is filled with rebar and river sand, and there is a metal injection molding on the outside of the expanded steel pipe. For slurry pipes, the end wall ends of expanded steel pipes are fixed with end clamps. The invention improves the seismic resistance and energy consumption and shock-absorbing performance of the cave door structure, can make the cave door end wall lightweight, thereby improving the problem of limited space; at the same time, it has the characteristics of convenient construction, low cost, and obvious benefits.

Description

A kind of earthquake-absorbing energy-consuming cave door and construction method under limited space conditions in strong earthquake areas

Technical field

The invention belongs to the technical field of underground engineering, and in particular relates to a shock-absorbing and energy-consuming tunnel door and a construction method under limited space conditions in strong earthquake areas.

Background technique

Tunnel portals are structures that are greatly affected by geological and topographical conditions, especially the portal end walls, which are facing the sky. When located in the broken surrounding rock in a strong earthquake zone, the end wall structure often suffers from structural damage, overturning, sliding and other earthquake damage under the action of earthquake forces. At present, in practice, tunnel engineering mostly uses gravity retaining walls for passive defense of portal end walls in strong earthquake zones, which have large structural mass, occupy a large space, and have limited earthquake resistance.

Contents of the invention

In view of the problem of limited space on the end wall of a portal in a strong earthquake zone, in order to improve the earthquake resistance and energy dissipation and shock absorption performance of the portal structure, the present invention provides a shock-absorbing and energy-absorbing portal and a construction method under space-limited conditions in a strong earthquake zone.

The present invention is a kind of earthquake-absorbing energy-dissipating cave door under limited space conditions in strong earthquake areas. It consists of a number of limited shock-absorbing energy-consuming pipes passing through the end wall of the cave door and the drainage layer behind the wall, and then extending into the rock and soil mass.

The main body of the limited shock-absorbing and energy-absorbing pipe is an expanded steel pipe and a concrete anchor at the end of the expanded steel pipe. The expanded steel pipe is filled with threaded steel and river sand. A metal grouting pipe is arranged on the outside of the expanded steel pipe. The end wall of the expanded steel pipe is fixed with an end clamp.

Further, the pipe diameter D _out at the end wall end of the expanded steel pipe is smaller than the pipe diameter D _in at the anchor end.

Furthermore, the concrete anchors are equipped with steel bars, and the steel bars are welded to the expanded steel pipes and metal grouting pipes.

Furthermore, the rebar in the expanded steel pipe is clamped by steel clamps.

The present invention provides a construction method for earthquake-absorbing energy-consuming cave doors under limited space conditions in strong earthquake areas. The specific steps are:

Step 1: Carry out grouting reinforcement to the rock and soil mass. The reinforcement should satisfy the stability of the cave door under static conditions.

Step 2: Construct the drainage layer behind the wall and the end wall of the door, and reserve space for the installation of limited shock-absorbing energy-consuming pipes in the end wall.

Step 3: Drill holes to a sufficient depth and expand the concrete anchor area.

Step 4: Put the prefabricated integral steel bars, expanded steel pipes, and metal grouting pipes into the drill holes, and pour concrete to form concrete anchors.

Step 5: Inject grouting into the rock and soil around the expanded steel pipe through the metal grouting pipe to enhance the friction between the expanded steel pipe and the rock and soil.

Step 6: Place the integrated steel fixture and rebar that have been prefabricated in advance into the expanded steel pipe, and fill the pipe with river sand.

Step 7: Apply end clamps to make the portal end wall, drainage layer behind the wall, rock and soil body and limited shock-absorbing energy-absorbing pipe form a whole.

The beneficial technical effects of the present invention are:

The present invention improves the earthquake resistance and energy dissipation performance of the portal structure, and can make the portal end wall lightweight, thereby improving the problem of limited space. At the same time, the materials used are commonly used construction steel bars, sand, clamps, steel pipes, etc., which not only saves the end wall space, but also has the characteristics of convenient construction, low cost, and obvious benefits.

Description of drawings

FIG. 1 is a general diagram of the shock-absorbing and energy-consuming tunnel door of the present invention.

Figure 2 is a schematic diagram of the structure of the limit shock-absorbing energy-consuming tube.

Figure 3 is a schematic diagram of the expanded diameter steel pipe of the limited shock-absorbing energy-dissipating pipe.

In the picture: 1-end wall of the cave door; 2-drainage layer behind the wall; 3-rock and soil mass; 4-limited shock-absorbing energy-dissipating pipe; 5-concrete anchor; 6-reinforced steel bar; 7-expanded steel pipe; 8- Steel clamp; 9-rebar; 10-river sand; 11-end clamp; 12-metal grouting pipe.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

A kind of earthquake-absorbing energy-consuming cave door under limited space conditions in a strong earthquake zone of the present invention is shown in Figure 1. A number of limited shock-absorbing energy-consuming pipes 4 pass through the door end wall 1 and the drainage layer 2 behind the wall, and then It is composed of 3 parts extending into the rock and soil mass.

As shown in Figure 2, the main body of the limit shock-absorbing energy-dissipating pipe 4 is an expanded steel pipe 7 and a concrete anchor 5 at the end of the expanded steel pipe 7. The expanded steel pipe 7 is filled with rebar 9 and river sand 10. The expanded steel pipe 7 There is a metal grouting pipe 12 on the outside, and the end wall end of the expanded steel pipe 7 is fixed with an end clamp 11.

Further, as shown in Figure 3, the diameter D _out of the end wall end of the expanded steel pipe 7 is smaller than the diameter D _in of the anchor end.

Further, the concrete anchor 5 is provided with steel bars 6, and the steel bars 6 are welded to the expanded steel pipe 7 and the metal grouting pipe 12.

Further, the rebar 9 in the expanded steel pipe 7 is clamped by a steel clamp 8 .

The present invention provides a construction method for a shock-absorbing and energy-absorbing tunnel door under space-constrained conditions in a strong earthquake zone, and the specific steps are as follows:

Step 1: Carry out grouting reinforcement on the rock and soil mass 3. The reinforcement should satisfy the stability of the cave door under static conditions.

Step 2: Construct the drainage layer 2 behind the wall and the end wall 1 of the door. Reserve space for the installation of the limit shock-absorbing energy-consuming pipe 4 in the end wall.

Step 3: Drill to sufficient depth and expand within the concrete anchor body.

Step 4: Put the prefabricated integral steel bars 6, expanded steel pipes 7, and metal grouting pipes 12 into the drill hole, and pour concrete to form the concrete anchor 5.

Step 5: Inject grouting into the rock and soil around the expanded steel pipe 7 through the metal grouting pipe 12 to enhance the friction between the expanded steel pipe 7 and the rock and soil 3 .

Step 6: Place the integrated steel clamp 8 and rebar 9 that are prefabricated in advance into the expanded steel pipe 7, and fill the pipe with river sand 10.

Step 7: Construct the end clamp 11 to make the end wall of the cave door 1, the drainage layer behind the wall 2, the rock and soil body 3 and the limit shock-absorbing energy-dissipating pipe 4 form a whole.

The end wall of the cave door 1, the drainage layer behind the wall 2, the rock and soil body 3, and the limit shock-absorbing energy-dissipating pipe 4 of the present invention form a complete system. When an earthquake occurs, the rock and soil body 3 sequentially opposes the drainage layer behind the wall 2 and the cave. The door end wall 1 generates seismic earth pressure. At this time, the limited shock-absorbing energy-dissipating pipe 4 reduces the seismic energy through the friction between the internal steel clamp 8, the rebar 9, the river sand 10 and the expanded steel pipe 7, and transfers the residual energy. to the expanded steel pipe 7. At the same time, since the diameter D _out of the end wall end of the expanded steel pipe 7 is smaller than the pipe diameter D _in of the anchor end, the steel clamp 8, rebar 9 and river sand 10 inside it play a limiting role. , the expanded steel bar 7 transmits the force to the concrete anchor 5 through the steel bar 6, thereby achieving the effect of limiting shock absorption and energy dissipation.

Claims (5)

1. A shock-absorbing and energy-absorbing tunnel portal under space-constrained conditions in a strong earthquake zone, characterized in that it is composed of a plurality of limited shock-absorbing and energy-absorbing pipes (4) passing through the tunnel portal end wall (1) and the drainage layer behind the wall (2), and then extending into the rock and soil body (3); The main body of the limit shock-absorbing energy-dissipating pipe (4) is an expanded steel pipe (7) and a concrete anchor (5) at the end of the expanded steel pipe (7). The expanded steel pipe (7) is filled with rebar (9) and River sand (10), a metal grouting pipe (12) is provided on the outside of the expanded steel pipe (7), and the end wall end of the expanded steel pipe (7) is fixed with an end clamp (11). 2. A kind of earthquake-absorbing energy-dissipating door under limited space conditions in strong earthquake zones according to claim 1, characterized in that the pipe diameter D _{out of} the end wall end of the expanded diameter steel pipe (7) is smaller than that of the anchor end. Pipe diameter D _in . 3. According to the shock-absorbing and energy-absorbing tunnel portal for use in space-constrained areas in strong earthquake zones as described in claim 1, it is characterized in that a steel bar (6) is provided inside the concrete anchor body (5), and the steel bar (6) is connected to the expanded diameter steel pipe (7) and the metal grouting pipe (12) by welding. 4. A kind of earthquake-absorbing energy-dissipating door under limited space conditions in strong earthquake zones according to claim 1, characterized in that the rebar (9) in the expanded diameter steel pipe (7) adopts a steel clamp ( 8) Clamping. 5. A construction method for earthquake-absorbing energy-consuming cave doors under limited space conditions in strong earthquake areas according to claim 1, characterized in that the specific steps are: Step 1: Carry out grouting reinforcement on the rock and soil mass (3). The reinforcement should satisfy the stability of the cave door under static conditions; Step 2: Construct the drainage layer behind the wall (2) and the end wall of the door (1), and reserve space for the installation of the limit shock-absorbing energy-consuming pipe (4) in the end wall; Step 3: Drill to a sufficient depth and expand the concrete anchor body; Step 4: Put the prefabricated integral steel bars (6), expanded steel pipes (7), and metal grouting pipes (12) into the drill holes, and pour concrete to form concrete anchors (5); Step 5: Inject grouting into the rock and soil around the expanded steel pipe (7) through the metal grouting pipe (12) to enhance the friction between the expanded steel pipe (7) and the rock and soil (3); Step 6: Place the prefabricated integrated steel clamp (8) and rebar (9) into the expanded steel pipe (7), and fill the pipe with river sand (10); Step 7: Apply the end fixture (11) to form the portal end wall (1), the drainage layer behind the wall (2), the rock and soil body (3) and the limit shock absorption energy dissipation pipe (4) into a whole.