CN113137247B - Method for improving concrete pouring efficiency and compactness of tunnel secondary lining arch wall - Google Patents

Abstract

The invention discloses a method for improving the concrete pouring efficiency and density of the second lining arch wall of a tunnel. During the construction of the arch wall, a steel formwork trolley is used as a template. The steel formwork trolley is equipped with multiple pouring openings and belt mold grouting. hole, and use a small piece of steel form to seal the end mold; when pouring, connect the pump pipe to the end pouring port, open all the pouring port gates and pour high-performance micro-expansion self-compacting concrete. There is no need to switch the pouring port during the pouring process. The single pouring port is used to push the concrete to the far end for pouring, and the pouring density is judged based on the mold grouting holes and end mold overflow conditions. After the pouring is completed, the molded grouting is performed immediately, which greatly improves the pouring efficiency and the secondary lining. The density of the arch wall pouring effectively ensures the quality of tunnel construction.

Description

A method to improve the concrete pouring efficiency and density of the secondary lining arch wall of a tunnel

Technical field

The invention relates to the technical field of tunnel secondary lining construction, specifically a method for improving the concrete pouring efficiency and compactness of the tunnel secondary lining arch wall.

Background technique

In the field of tunnel secondary lining construction, arch wall construction will more or less have the common quality problem of poor pouring and cavities in the vault, and the pouring efficiency is extremely low. The reasons are as follows: First, the air in the vault is not discharged, forming a cavity and causing The concrete at the vault is not full; secondly, the end form sealing has poor reliability and cannot withstand large pump pressure, resulting in the inability to properly overfill; thirdly, there is shrinkage during the concrete curing process, causing the vault to become hollow; fourthly, the secondary lining of steel bars The effect of intensive vibration arrangement is not good; fifthly, the pouring port needs to be replaced frequently, the pump is stopped frequently, cold joints are easily formed, and the pouring time is increased. Therefore, how to improve the concrete pouring density and pouring efficiency of the secondary lining arch wall is the key to determining the success or failure of the secondary lining construction.

Contents of the invention

In order to overcome the above-mentioned technical defects in the prior art, the present invention provides a method for improving the concrete pouring efficiency and compactness of the second lining arch wall of a tunnel. During the arch wall pouring process, there is no need to frequently switch pouring ports, which greatly improves the pouring efficiency and density. The pouring density of the secondary lining arch wall effectively ensures the quality of tunnel construction and solves the above technical problems.

The present invention achieves the above object through the following technical solution: a method for improving the concrete pouring efficiency and compactness of the second lining arch wall of a tunnel. The arch wall pouring formwork used in this method is a steel formwork trolley, and the concrete adopts high-performance micro-expansion automatic For dense concrete, formwork grouting is required after the pouring is completed.

The steel formwork trolley is equipped with multiple pouring openings and molded grouting holes. The molded grouting holes are set on both sides of the pouring opening. The pouring opening is equipped with movable gates. The steel formwork trolley is equipped with a small shaped steel mold for end The mold is sealed, and the small shaped steel mold is connected to the end flange of the steel mold trolley using bolts. The bolt holes are all oblong holes, and angle steel back ribs are set up to strengthen the small shaped steel mold and improve the pressure bearing capacity of the end mold. , the oblong hole on the small shaped steel mold is a radial oblong hole, the oblong hole on the steel formwork trolley flange is a circumferential oblong hole, the slump expansion of high-performance micro-expansion self-compacting concrete into the mold is not less than 600mm, the limit The expansion rate is greater than 0.015%.

The circumferential adjustment can ensure that the small pieces of shaped steel molds are installed tightly, and the radial adjustment can ensure that the small pieces of shaped steel molds are closely connected to the initial support surface.

A method to improve the concrete pouring efficiency and density of the secondary lining arch wall of a tunnel includes the following construction steps:

S1: Install the molded grouting pipe in place and open all pouring gates;

S2: Connect the pump pipe to the end pouring port for pouring;

S3: When pouring reaches the observation window of the side mold, stop the pump appropriately and turn on the flat vibrator for vibration;

S4: When other pouring openings overflow with grout, close their gates and continue pouring until all grouting pipes with molds and the highest ends of the end molds overflow with grout, then the pouring can be completed.

The above-mentioned method to improve the concrete pouring efficiency and compactness of the secondary lining arch wall of the tunnel is to use only the end pouring for single-port pouring during the entire pouring process without changing the pouring port.

The above-mentioned method of improving the concrete pouring efficiency and compactness of the secondary lining arch wall of a tunnel, the described grouting with formwork is implemented immediately after the pouring is completed.

Generally speaking, compared with the prior art, the above technical solutions conceived by the present invention can achieve the following beneficial effects: The present invention is a method for improving the concrete pouring efficiency and compactness of the secondary lining arch wall of a tunnel. During the arch wall pouring process, There is no need to frequently switch pouring openings, which greatly improves the pouring efficiency and the pouring density of the secondary lining arch wall, effectively ensuring the quality of tunnel construction.

Description of the drawings

The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings, wherein:

Figure 1 is a layout diagram of the pouring opening of the steel formwork trolley and the grouting hole with the mold according to the present invention;

Figure 2 is a schematic structural diagram of a small shaped steel mold used in the end mold sealing of the present invention;

In the picture: 1-pouring port, 2-grouting hole with mold, 3-observation window, 4-small shaped steel mold, 5-angle steel, 6-oblong hole.

Detailed ways

The invention is a method for improving the concrete pouring efficiency and compactness of the secondary lining arch wall of a tunnel. The arch wall pouring template used in the method is a steel formwork trolley, and the concrete is made of high-performance micro-expansion self-compacting concrete. After the pouring is completed, it needs to be belted. Mold grouting.

The steel formwork trolley is provided with multiple pouring openings 1 and molded grouting holes 2. The layout of the pouring openings 1 and molded grouting holes 2 on the steel formwork trolley is shown in Figure 1. The molded grouting holes 2 are arranged on On both sides of the pouring port 1, the pouring port 1 is provided with movable gates, and the side end face of the steel mold trolley is equipped with a small shaped steel mold 4 for end mold sealing.

The small shaped steel mold 4 used for end mold sealing is shown in Figure 2. The small shaped steel mold 4 is connected to the end flange of the steel mold trolley by bolts. The bolt holes are all oblong holes 6, and angle steel 5 is provided on the back. The small shaped steel mold 4 is reinforced. The oblong holes 6 on the small shaped steel mold 4 are radial oblong holes, and the oblong holes 6 on the flange of the steel mold trolley are circumferential oblong holes. High-performance micro-expansion automatic The slump expansion of dense concrete into the mold is not less than 600mm, and the limited expansion rate is greater than 0.015%.

The pouring method includes the following construction steps:

Step 1: Install the molded grouting pipe in place and open all pouring port 1 gates;

Step 2: Connect the pump pipe to the end pouring port 1 for pouring;

Step 3: When pouring reaches the observation window of the side mold, stop the pump appropriately and turn on the flat vibrator for vibration;

Step 4: When the other pouring port 1 overflows with grout, close its gate and continue pouring until all the molded grouting pipes and the highest end of the end mold overflow with grout, then the pouring can be completed.

During the entire pouring process, only the end pouring port 1 is used for single pouring without changing the pouring port. Grouting with formwork is performed immediately after the concrete pouring is completed.

The process of the invention is simple, and there is no need to frequently switch the pouring opening during the arch wall pouring process, which greatly improves the pouring efficiency and the pouring density of the secondary lining arch wall, and effectively ensures the quality of tunnel construction.

It is easy for those skilled in the art to understand that the above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements, etc., made within the spirit and principles of the present invention, All should be included in the protection scope of the present invention.

Claims (3)

1. A method for improving the concrete pouring efficiency and compactness of a second lining arch wall of a tunnel is characterized in that an arch wall pouring template used in the method is a steel mould trolley, the concrete adopts high-performance micro-expansion self-compacting concrete, and grouting with a mould is carried out after pouring is completed;

the steel mould trolley is provided with a plurality of pouring ports (1) and grouting holes (2) with moulds, the grouting holes (2) with moulds are arranged on two sides of the pouring ports (1), the pouring ports (1) are provided with movable flashboards, the steel mould trolley is provided with small-sized steel moulds (4) for end mould plugging, the small-sized steel moulds (4) are connected with end flanges of the steel mould trolley by bolts, bolt holes are slotted holes (6), angle steel (5) back edges are arranged to strengthen the small-sized steel moulds (4), the slotted holes (6) on the small-sized steel moulds (4) are radial slotted holes, the slotted holes (6) on the flanges of the steel mould trolley are annular slotted holes, and the expansion degree of the high-performance micro-expansion self-compacting concrete in mould falling is not less than 600mm, and the expansion rate of the high-performance micro-expansion self-compacting concrete is limited to be more than 0.015;

the pouring method comprises the following construction steps:

s1: installing grouting pipes with moulds in place, and opening flashboards of all pouring ports (1);

s2: connecting a pump pipe to an end pouring opening (1) for pouring;

s3: when pouring the concrete into the side mold observation window, properly stopping the pump, and starting the flat vibrator to vibrate;

s4: and when the other pouring ports (1) overflow, closing the flashboard of the pouring ports to continue pouring until all grouting pipes with the moulds and the highest ends of the end moulds overflow, and thus pouring can be completed.

2. The method for improving the concrete pouring efficiency and compactness of the tunnel double-lining arch wall according to claim 1, wherein the whole pouring process only uses the end pouring port (1) to perform single-port pouring without replacing the pouring port.

3. The method for improving the concrete pouring efficiency and compactness of the double-lining arch wall of the tunnel according to claim 1, wherein the grouting with the mould is performed immediately after the pouring is completed.