CN-121993233-A - Active sealing method for locking gap of electrothermal expansion type bundling pipe curtain

CN121993233ACN 121993233 ACN121993233 ACN 121993233ACN-121993233-A

Abstract

The invention discloses an active sealing method for a locking gap of an electrothermal expansion type binding pipe curtain, which comprises the steps of distributing a hot melt adhesive expansion material which coats a conductive element and is in a solid state at the locking gap of adjacent steel pipes in the binding pipe curtain, jacking the steel pipes into a stratum, enabling the locking buckles of the adjacent steel pipes to be mutually meshed to form the binding pipe curtain, electrifying the conductive element which coats the hot melt adhesive expansion material at the locking gap of the adjacent steel pipes in the binding pipe curtain, applying control current to enable the conductive element to generate joule heat and conduct the joule heat to the hot melt adhesive expansion material, enabling the heated molten hot melt adhesive expansion material in the locking gap to be in a liquid state to flow and the volume expansion to be filled in the locking gap, stopping electrifying, enabling the heated hot melt adhesive expansion material in the liquid state to be cooled to be in a solid state to be solidified in the locking gap to form a continuous permanent sealing body, and sealing water stopping the locking positions of the binding pipe curtain. The invention improves the sealing water-stopping effect at the pipe curtain lock catch of the adjacent steel pipes.

Inventors

LUO YUNFENG
YANG ZISONG
CHEN ZHIQIANG
ZOU FENG
WEN TIANYI
LU SANPING
HE JIAN

Assignees

上海市基础工程集团有限公司

Dates

Publication Date: 20260508
Application Date: 20260128

Claims (10)

1. An active sealing method for a locking gap of an electrothermal welding expansion type bundling pipe curtain is characterized by comprising the following steps: Step S1, before the construction of the bunching pipe curtain, hot melt adhesive expansion materials which are used for cladding the conductive elements and are in a solid state are distributed at the lock catch gaps of the adjacent steel pipes, and the melting point temperature of the hot melt adhesive expansion materials is smaller than that of the steel pipes; S2, pushing the steel pipes with the hot melt adhesive expansion materials which are coated with the conductive elements and are in a solid state into a stratum, enabling the lock catches of the adjacent steel pipes to be mutually engaged, and sealing the hot melt adhesive expansion materials coated with the conductive elements in the lock catches to form a beam-combined pipe curtain; And S3, applying control current to the conductive element coated in the hot melt adhesive expansion material at the lock catch gap of the adjacent steel pipes in the bundling pipe curtain, so that the conductive element generates joule heat and is conducted to the hot melt adhesive expansion material, the hot melt adhesive expansion material in the lock catch gap is heated and then melted into liquid state to flow and expand and fill the lock catch gap in volume, stopping electrifying, and cooling the hot melt adhesive expansion material in the liquid state into solid state to solidify in the lock catch gap to form a continuous permanent sealing body to seal and stop water at the lock catch of the bundling pipe curtain.
2. The active sealing method of the locking gap of the electrothermal expansion type bundling pipe curtain according to claim 1, wherein the hot melt adhesive expansion material of the coated conductive element arranged at the locking gap of the adjacent steel pipe is processed into strips, sheets or profiled bars matched with the locking shape, and is fixedly arranged at the locking gap by means of bonding, clamping or mechanical connection.
3. The active sealing method of the locking gap of the electric heating expansion type binding pipe curtain according to claim 2, wherein the locking comprises a male locking device and a female locking device which are matched with each other, the adjacent steel pipes comprise a steel pipe with the male locking device and a steel pipe with the female locking device, and the strip-shaped, sheet-shaped or profiled bars matched with the locking shape are fixedly arranged on the inner wall of the female locking device and/or the outer wall of the male locking device.
4. The method of claim 3, wherein the lock is a CT type lock or a circular lock.
5. The method of claim 1, wherein the expansion ratio of the solid hot melt adhesive expansion material is between 150% and 500% and the melting point temperature is between 80 ℃ and 160 ℃.
6. The method of claim 1, wherein the conductive element is a high-resistance heating wire or a conductive carbon fiber.
7. The method of actively sealing a snap-fit gap of an electrothermal expansion type tube curtain according to claim 6, wherein the high-resistance heating wire is nichrome high-resistance heating wire.
8. The method for actively sealing the locking gap of the electrothermal welding expansion type binding pipe curtain according to claim 1, the control circuit is characterized in that the control current is direct current or power frequency alternating current.
9. The active sealing method for the locking gaps of the electrothermal expansion type binding pipe curtain according to claim 1, wherein the conductive elements coated in the hot melt adhesive expansion materials at the locking gaps in the binding pipe curtain are connected into a plurality of heating loops in parallel, and each heating loop is independently electrified and controlled to realize sealing water stopping at the locking positions at corresponding positions in different areas and stages.
10. The active sealing method for the locking gaps of the electric heating melting expansion type combined pipe curtain according to claim 1, wherein the conductive elements coated in the hot melt adhesive expansion materials at the locking gaps in the combined pipe curtain are connected in series to form a heating loop, and sealing water stopping is achieved at all locking positions in the combined pipe curtain by conducting overall power-on control on the heating loop.

Description

Active sealing method for locking gap of electrothermal expansion type bundling pipe curtain Technical Field The invention relates to the field of civil engineering, in particular to an active sealing method for a locking gap of an electrothermal welding expansion type binding pipe curtain. Background In underground engineering such as tunnels, a pipe curtain construction method is an advanced construction method for forming a temporary or permanent supporting structure by jacking a series of steel pipes in underground excavation construction. These steel pipes are usually interlocked with each other by special locking structures at their edges to form a continuous pipe curtain. However, in the jacking process, due to complicated geological conditions, great difficulty in jacking accuracy control and the like, a tiny gap is inevitably formed between the catches of adjacent steel pipes. These gaps are the main channels for groundwater leakage, which can seriously threaten construction safety, cause water and sand gushes in pits, even cause ground subsidence, and destroy surrounding buildings. In order to seal the lock catch gap, one method of the traditional mode is to pre-embed a water-swelling rubber strip in the lock catch gap. The mode relies on underground water soaking to slowly expand, and belongs to passive water stopping. When the pressure water head is high or the water flow is rapid, the expansion speed and the sealing pressure are often insufficient to effectively seal the gap, and the reliability is good. And the other method is that grouting and sealing are carried out on the lock catch gap from the inside after all the steel pipes are jacked in to form a pipe curtain. The method has the defects of complex construction procedures, drilling, laying grouting pipes and the like, difficult control of the fluidity and filling degree of the slurry in a narrow space of the lock catch, easy formation of a sealing blind area, poor sealing effect and unstable water stopping effect. Disclosure of Invention The invention aims to provide an active sealing method for a locking gap of an electrothermal melting expansion type binding pipe curtain, which aims to solve the problems that the locking gap of the binding pipe curtain can be sealed by adopting a water swelling rubber strip method depending on underground water soaking, and the sealing water stopping effect is poor and unreliable under the condition of higher pressure water head or higher water flow, and the problems that the construction process is complex, the mobility and filling degree of slurry in a narrow space of a lock are difficult to control due to the adoption of a grouting mode for sealing the locking gap, and a sealing blind area is easy to form, so that the sealing water stopping effect is poor. In order to solve the technical problems, the technical scheme provided by the invention is that an active sealing method for a locking gap of an electrothermal welding expansion type binding pipe curtain comprises the following steps: Step S1, before the construction of the bunching pipe curtain, hot melt adhesive expansion materials which are used for cladding the conductive elements and are in a solid state are distributed at the lock catch gaps of the adjacent steel pipes, and the melting point temperature of the hot melt adhesive expansion materials is smaller than that of the steel pipes; S2, pushing the steel pipes with the hot melt adhesive expansion materials which are coated with the conductive elements and are in a solid state into a stratum, enabling the lock catches of the adjacent steel pipes to be mutually engaged, and sealing the hot melt adhesive expansion materials coated with the conductive elements in the lock catches to form a beam-combined pipe curtain; And S3, applying control current to the conductive element coated in the hot melt adhesive expansion material at the lock catch gap of the adjacent steel pipes in the bundling pipe curtain, so that the conductive element generates joule heat and is conducted to the hot melt adhesive expansion material, the hot melt adhesive expansion material in the lock catch gap is heated and then melted into liquid state to flow and expand and fill the lock catch gap in volume, stopping electrifying, and cooling the hot melt adhesive expansion material in the liquid state into solid state to solidify in the lock catch gap to form a continuous permanent sealing body to seal and stop water at the lock catch of the bundling pipe curtain. Further, according to the active sealing method for the locking gaps of the electrothermal expansion type binding pipe curtain, the hot melt adhesive expansion materials which are distributed at the locking gaps of the adjacent steel pipes and are used for coating the conductive elements are processed into strip-shaped, sheet-shaped or profiled bars matched with the locking shapes, and the profiled bars are fixedly arranged at the locking gaps in a bonding, c