CN-224214192-U - Constant-temperature anti-cracking structure for secondary lining concrete of entrance to a cave section in alpine region

CN224214192UCN 224214192 UCN224214192 UCN 224214192UCN-224214192-U

Abstract

The utility model relates to the technical field of tunnel construction in alpine regions, in particular to a secondary lining concrete constant-temperature anti-cracking structure for an opening section in the alpine regions. The constant-temperature anti-cracking structure of the secondary lining concrete for the tunnel portal section in the alpine region comprises embedded pipes, heating modules and waterproof structure layers, wherein a plurality of axial embedded pipes are embedded in the secondary lining concrete for the tunnel portal section, the heating modules are inserted into the embedded pipes, and the waterproof structure layers are embedded in the outer peripheral surface of the secondary lining concrete for the tunnel portal section. The automatic control device can quickly respond to external temperature change so as to timely adjust the actively heated temperature, realizes constant-temperature anti-cracking of the secondary lining concrete, and has the advantages of low maintenance cost, no leakage risk and the like.

Inventors

ZHANG BINBIN
LI YALONG
MAO JINBO
CHEN SHUO
FAN ZERUI

Assignees

中交二公局东萌工程有限公司

Dates

Publication Date: 20260508
Application Date: 20250627

Claims (10)

1. The utility model provides a high and cold district entrance to a cave section secondary lining concrete constant temperature crack control structure which characterized in that includes: The embedded pipes (21) are embedded in the secondary lining concrete (1) at the opening section, and a plurality of axial embedded pipes (21) are embedded in the secondary lining concrete; The heating modules are inserted into the embedded pipes (21); The waterproof structure layer (22) is embedded in the outer peripheral surface of the secondary lining concrete (1) at the opening section.
2. The alpine region entrance to a cave section secondary lining concrete constant temperature crack control structure of claim 1, further comprising: The heat insulation structure layer (23), heat insulation structure layer (23) lays in the surface of entrance to a cave section secondary lining concrete (1), to the outer peripheral face of entrance to a cave section secondary lining concrete (1), heat insulation structure layer (23) are located waterproof structure layer (22) with between the outer peripheral face.
3. The secondary lining concrete constant temperature anti-cracking structure for the entrance to a cave in alpine regions according to claim 1, wherein, The heating module comprises a shell (31), an electric heating wire (32) and a first filler, wherein the electric heating wire (32) is inserted into the shell (31) and a first gap (33) is formed between the electric heating wire and the shell (31), and the first filler is filled in the first gap (33) and is thermally conductive and insulating; The heating module is provided with supporting frames (34) at intervals outside, a second gap (35) is formed between the heating module inserted into the embedded pipe (21) and the embedded pipe (21), and the second gap (35) is filled with a second heat-conducting filler.
4. The secondary lining concrete constant temperature anti-cracking structure for the entrance to a cave in alpine region according to claim 3, The electric heating wire (32) is a nichrome wire; the first filler and the second filler are selected from one or more of magnesia powder, alumina powder and boron nitride powder.
5. The secondary lining concrete constant temperature anti-cracking structure for the entrance to a cave in alpine regions according to claim 1, wherein, Each embedded pipe (21) is uniformly distributed along the annular direction of the secondary lining concrete (1) of the opening section; For any two adjacent embedded pipes (21), the two adjacent embedded pipes (21) are connected through a plurality of heat conducting rods (24).
6. The secondary lining concrete constant temperature anti-cracking structure for the entrance to a cave in alpine regions according to claim 5, wherein, The distances from each point on the central line of the heat conducting rod (24) to the inner peripheral surface of the secondary lining concrete (1) of the opening section are equal; The heat conducting rods (24) are uniformly distributed along the axial direction of the secondary lining concrete (1) of the opening section.
7. The secondary lining concrete constant temperature anti-cracking structure for the entrance to a cave in alpine regions according to claim 6, wherein, A plurality of radial drilling holes (41) are formed in the inner peripheral surface, temperature sensors (42) are mounted in the drilling holes (41), and gaps between the temperature sensors (42) and the drilling holes (41) are filled with heat-conducting silicone grease (43).
8. The secondary lining concrete constant temperature anti-cracking structure for the entrance to a cave in alpine regions according to claim 6, wherein, A plurality of mounting cylinders (44) are pre-buried in the hole section secondary lining concrete (1), and the axes of the mounting cylinders (44) are along the radial direction of the hole section secondary lining concrete (1) and the opening side is flush with the inner peripheral surface; A plurality of heat conducting fins (45) extend on the outer peripheral wall of the mounting cylinder (44), and threads are formed on the inner peripheral wall of the opening section of the mounting cylinder (44); a temperature sensor (42) is arranged in each mounting cylinder (44), a gap between the temperature sensor (42) and the mounting cylinders (44) is filled with heat-conducting silicone grease (43), and the opening side of the mounting cylinders (44) is plugged by threaded connection of an end cover (46).
9. The secondary lining concrete constant temperature anti-cracking structure for the entrance to a high and cold area according to claim 7 or 8, wherein, For any one temperature sensor (42), the temperature sensor (42) is positioned in a grid formed by the embedded pipe (21) and the heat conducting rod (24) and positioned at the intersection point of the diagonal lines of the grid.
10. The high and cold district entrance to a cave section secondary lining concrete constant temperature crack control structure according to claim 7 or 8, characterized by further comprising: And the control terminal is electrically connected with the temperature sensors (42) and the heating modules, and can respond to the temperature signals transmitted by the temperature sensors (42) to adjust the heating temperature of the heating modules.

Description

Constant-temperature anti-cracking structure for secondary lining concrete of entrance to a cave section in alpine region Technical Field The utility model relates to the technical field of tunnel construction in alpine regions, in particular to a secondary lining concrete constant-temperature anti-cracking structure for an opening section in the alpine regions. Background The tunnel portal section in the alpine region faces extremely low temperature (the lowest temperature in the year is usually lower than-10 ℃ to-30 ℃) and severe freeze thawing cycle (the annual cycle times can reach 50-100 times). Such extreme low temperatures and frequent freeze thawing often lead to cracking of the secondary lining concrete, which in turn leads to a substantial decrease in its strength and durability. The secondary lining concrete of the tunnel portal is a core bearing layer of the tunnel structure, the compressive strength and the durability of the secondary lining concrete directly determine the safety and the service life of the tunnel, and therefore, corresponding measures are necessary to protect the secondary lining concrete of the tunnel portal. When the Chinese patent CN202110832058.2 utilizes the heat transfer circulation medium to circulate in the heat exchange tube loop, the heat exchange is carried out with underground rock, the heat is absorbed, and the absorbed heat is respectively lifted through the first ground source heat pump and the second ground source heat pump, so that the heat transfer circulation medium in the first heat supply tube loop and/or the second heat supply tube loop reaches a certain temperature requirement, and the heat transfer circulation medium is subjected to primary lining, secondary lining and tunnel internal temperature rise in the heat supply tube. However, when the temperature of the underground rock is unstable and is usually lower, the underground rock is influenced by the environmental temperature and correspondingly reduced, so that when the method is used for heat preservation, the situation that the external environmental temperature is lower and higher heating power is needed is not easy to succeed, a circulating medium needs to flow to the underground rock to absorb heat and then pump the heat to a region to be heated, the response speed is low, in addition, the heat conducting medium realizes the circulating flow through an embedded pipeline, when the heat conducting medium leaks due to the reasons of pipe aging, joint loosening, construction damage, frost heaving damage and the like, the lining is needed to be damaged by maintenance or replacement of the pipeline, the workload is high, the normal operation of a tunnel is influenced, the leaked liquid permeates into the lining structure, and the local frost heaving possibly causes cracks, peeling or lining deformation. Disclosure of utility model The utility model aims to provide a constant-temperature anti-cracking structure for secondary lining concrete at an entrance to a tunnel in a alpine region, which can at least partially overcome the technical problems, can quickly respond to external temperature change so as to timely adjust the active heating temperature, realizes constant-temperature anti-cracking of the secondary lining concrete, and has the advantages of low maintenance cost, no leakage risk and the like. The constant-temperature anti-cracking structure for the secondary lining concrete of the tunnel portal section in the alpine region comprises embedded pipes, heating modules and waterproof structure layers, wherein a plurality of axial embedded pipes are embedded in the secondary lining concrete of the tunnel portal section, the heating modules are inserted into the embedded pipes, and the waterproof structure layers are embedded in the outer peripheral surface of the secondary lining concrete of the tunnel portal section. Further, this thermal insulation structure of thermal insulation of entrance to a cave section secondary lining concrete still includes the insulation structure layer, the insulation structure layer lays the surface of entrance to a cave section secondary lining concrete is right the outer peripheral face of entrance to a cave section secondary lining concrete, the insulation structure layer is located waterproof structure layer with between the outer peripheral face. The heating module comprises a shell, an electric heating wire and a first filler, wherein the electric heating wire is inserted into the shell, a first gap is formed between the electric heating wire and the shell, the first filler is filled in the first gap and is conductive and insulating, a supporting frame is arranged outside the heating module at intervals, a second gap is formed between the heating module inserted into the embedded pipe and the embedded pipe, and the second gap is filled with a conductive second filler. Further, the electric heating wire is a nichrome wire, and the first filler and the second f