阅读说明：本技术 自动步道的端头井施工方法 (Construction method of end well of automatic footpath ) 是由 梁磊涛 李建军 李五红 赵朋宪 李钢 王永霞 于 2020-07-17 设计创作，主要内容包括：本发明提供一种自动步道的端头井施工方法,包括：S1)在地下通道内地面上放样端头井的施工区,定义被施工区包围的每一矩形管节上的区域为待切割部；S2)在距离施工区给定距离处设置多根垂直地面的竖向支撑柱；S3)在施工区上方垂直地面给定高度处设置多根垂直竖向支撑柱的横向支撑柱；S4)切割每一矩形管节上的待切割部以形成端头井导坑；S5)垂直地面并沿端头井导坑的纵深方向开挖给定深度以形成端头井基坑,支护端头井基坑,完成自动步道的端头井施工。该端头井施工方法,通过多根横向支撑柱和多根竖向支撑柱对施工区周边的地下通道结构进行提前加固,避免了在地下通道中施做端头井时地下通道结构变形、塌陷等问题的发生。(The invention provides a construction method of an end well of an automatic footpath, which comprises the following steps: s1) lofting the construction area of the end well on the ground in the underground passage, and defining the area on each rectangular pipe joint surrounded by the construction area as a to-be-cut part; s2) arranging a plurality of vertical supporting columns vertical to the ground at a given distance from a construction area; s3) arranging a plurality of transverse supporting columns of the vertical supporting columns above the construction area at a given height vertical to the ground; s4) cutting the to-be-cut part on each rectangular pipe section to form an end well guide pit; s5) excavating a given depth along the depth direction of the end well guide pit to form an end well foundation pit, supporting the end well foundation pit, and completing the construction of the end well of the automatic footpath. According to the end well construction method, the underground passage structures at the periphery of the construction area are reinforced in advance through the plurality of transverse supporting columns and the plurality of vertical supporting columns, so that the problems of deformation, collapse and the like of the underground passage structures when the end is constructed in the underground passage are avoided.)

1. An end well construction method of an automatic walkway is implemented in an underground passage formed by connecting a plurality of sections of rectangular pipe joints after pipe jacking construction, and is characterized by comprising the following steps:

s1) lofting a construction area of a head well of the automatic walking way on the ground in the underground passage, and defining an area on each rectangular pipe joint surrounded by the construction area as a to-be-cut part;

s2) arranging a plurality of vertical supporting columns vertical to the ground at a given distance from the construction area, wherein two end faces of each vertical supporting column are respectively abutted against the ground and the top face of the underground passage;

s3) arranging a plurality of transverse supporting columns perpendicular to the vertical supporting columns at a given height above the construction area and perpendicular to the ground, wherein the end surfaces of two ends of each transverse supporting column are abutted against two side walls of the underground passage;

s4) cutting the to-be-cut part on each rectangular pipe joint to form an end well guide pit;

s5) excavating a given depth along the depth direction of the end well guide pit to form an end well foundation pit, supporting the end well foundation pit, and completing the construction of the end well of the automatic footpath.

2. The method for constructing an end well of a travelator according to claim 1, characterized in that the to-be-cut portion on the rectangular pipe section is made of steel plate.

3. The method of constructing an end well of a travelator according to claim 1, characterized in that it further comprises:

and pre-burying a plurality of base plates in the specified rectangular pipe joints before the step S1), wherein the two end surfaces of each vertical supporting column are respectively connected with the corresponding base plates to be abutted against the ground and the top surface of the underground passage, and the two end surfaces of each transverse supporting column are respectively connected with the corresponding base plates to be abutted against the two side walls of the underground passage.

4. The method for constructing an end well of a travelator according to claim 3, characterized in that the vertical support columns and the horizontal support columns are fixed to the corresponding tie plates by welding.

5. The method of constructing an end well of a travelator according to claim 1, characterized in that it further comprises:

and before the step S1), grouting the periphery of the soil body to be excavated of the end well of the automatic pavement to be excavated through the embedded grouting pipes on each rectangular pipe joint.

6. The method of constructing an end well of a travelator according to claim 5, characterized in that it further comprises:

prior to step S4): sampling the sample soil around the soil body to be excavated of the end well of the automatic pavement to be excavated through the preset sampling holes on the rectangular pipe joints, detecting the strength of the sample soil, and executing the step S4) after the strength of the sample soil reaches the preset strength.

7. The method for constructing an end well of a travelator according to claim 1, wherein the step S5) of excavating a given depth in a depth direction of the end well guide pit perpendicular to the ground to form an end well foundation pit, supporting the end well foundation pit, and completing the construction of the end well of the travelator comprises:

s50) excavating towards the underground according to the profile of the end well guide pit until the excavation depth reaches a first depth to form a foundation pit section, installing a plurality of grid steel frames along the pit wall of the foundation pit section, and connecting adjacent grid steel frames by adopting connecting ribs;

s51) constructing a plurality of locking anchor pipes on the pit wall of the foundation pit section according to a given distance;

s52) spraying concrete with given thickness to the pit wall of the foundation pit section;

s53) grouting into the soil body around the foundation pit section through the anchor rods, wherein the grouting pressure is smaller than the preset grouting pressure value, and stopping grouting until grouting slurry is filled in the foot locking anchor pipes;

s54) repeating the steps S50) -S53) until the total depth of the multiple sections of foundation pit sections in the direction vertical to the ground reaches a given depth, and forming an end well foundation pit;

s55) paving a reinforcing mesh at the bottom of the end well foundation pit, and then pouring concrete with given thickness to the bottom of the end well foundation pit to complete the primary support construction of the end well foundation pit of the automatic footpath.

S56) performing waterproof construction, installing reinforcing steel bars and pouring concrete on the bottom and the wall of the end well foundation pit after primary support construction is completed in sequence, and completing end well construction.

8. The method for constructing an end well of a travelator according to claim 7, characterized in that the pre-set grouting pressure value is 2 Mpa.

Technical Field

The invention relates to the technical field of engineering construction, in particular to a construction method of an end well of an automatic footpath.

Background

In order to relieve increasingly congested urban traffic, underground passages are largely built in urban traffic construction to relieve road traffic, and in order to avoid influencing the normal operation of a road traffic system in the process of building the underground passages, pipe jacking construction is generally adopted to construct the underground passages. The pipe-jacking construction is a trenchless or non-trenchless pipeline embedding construction technology, and can pass through roads, railways, rivers, ground buildings, underground pipelines and the like without a trenched surface. After finishing a large-size underground passage by using pipe jacking technology construction, the time for a pedestrian to pass through the underground passage is long, in order to help the pedestrian to pass through the underground passage as soon as possible, the detention time of the pedestrian in the underground passage is reduced, an automatic walkway can be built in the large-size underground passage to help the pedestrian to rapidly pass through the underground passage, an end well needs to be arranged at the end of the automatic walkway for building the automatic walkway, the end well mainly comprises an equipment well for placing driving equipment and a water collecting well for collecting water, the end well is implemented in the underground passage to influence the structure of the whole underground passage, a serious person can damage the underground passage structure to cause deformation, collapse and the like of the underground passage, and therefore a method is urgently needed to solve at least one of the problems occurring when the end well is constructed.

Disclosure of Invention

The invention aims to solve the problems that an underground passage is easy to deform and sink when an end is constructed in the underground passage, and provides a construction method for constructing an automatic footpath end well in the underground passage, which can avoid the deformation and the sink of the underground passage to safely complete the construction of the automatic footpath in the underground passage and provide convenience for pedestrians to pass through the underground passage.

In order to achieve the above object, an embodiment of the present invention provides a method for constructing an end well of an automatic walkway, where the end well of the automatic walkway is constructed in an underground passage formed by connecting multiple sections of rectangular pipe joints after pipe jacking construction, and the method for constructing the end well of the automatic walkway includes the following steps:

s1) lofting a construction area of a head well of the automatic walking way on the ground in the underground passage, and defining an area on each rectangular pipe joint surrounded by the construction area as a to-be-cut part;

s2) arranging a plurality of vertical supporting columns vertical to the ground at a given distance from the construction area, wherein two end faces of each vertical supporting column are respectively abutted against the ground and the top face of the underground passage;

s3) arranging a plurality of transverse supporting columns perpendicular to the vertical supporting columns at a given height above the construction area and perpendicular to the ground, wherein the end surfaces of two ends of each transverse supporting column are abutted against two side walls of the underground passage;

s4) cutting the to-be-cut part on each rectangular pipe joint to form an end well guide pit;

s5) excavating a given depth along the depth direction of the end well guide pit to form an end well foundation pit, supporting the end well foundation pit, and completing the construction of the end well of the automatic footpath.

Specifically, the part to be cut on the rectangular pipe section is made of a steel plate.

Specifically, the construction method of the end well of the automatic footpath further comprises the following steps:

and pre-burying a plurality of base plates in the specified rectangular pipe joints before the step S1), wherein the two end surfaces of each vertical supporting column are respectively connected with the corresponding base plates to be abutted against the ground and the top surface of the underground passage, and the two end surfaces of each transverse supporting column are respectively connected with the corresponding base plates to be abutted against the two side walls of the underground passage.

Specifically, the vertical supporting columns and the horizontal supporting columns are fixed to the corresponding base plates through welding.

Specifically, the construction method of the end well of the automatic footpath further comprises the following steps:

and before the step S1), grouting the periphery of the soil body to be excavated of the end well of the automatic pavement to be excavated through the embedded grouting pipes on each rectangular pipe joint.

Specifically, the construction method of the end well of the automatic footpath further comprises the following steps:

prior to step S4): sampling the sample soil around the soil body to be excavated of the end well of the automatic pavement to be excavated through the preset sampling holes on the rectangular pipe joints, detecting the strength of the sample soil, and executing the step S4) after the strength of the sample soil reaches the preset strength.

Specifically, step S5) of excavating a given depth in a depth direction of the end well guide pit perpendicular to the ground to form an end well foundation pit, supporting the end well foundation pit, and completing construction of an end well of the travelator includes:

s50) excavating towards the underground according to the profile of the end well guide pit until the excavation depth reaches a first depth to form a foundation pit section, installing a plurality of grid steel frames along the pit wall of the foundation pit section, and connecting adjacent grid steel frames by adopting connecting ribs;

s51) constructing a plurality of locking anchor pipes on the pit wall of the foundation pit section according to a given distance;

s52) spraying concrete with given thickness to the pit wall of the foundation pit section;

s53) grouting into the soil body around the foundation pit section through the anchor rods, wherein the grouting pressure is smaller than the preset grouting pressure value, and stopping grouting until grouting slurry is filled in the foot locking anchor pipes;

s54) repeating the steps S50) -S53) until the total depth of the multiple sections of foundation pit sections in the direction vertical to the ground reaches a given depth, and forming an end well foundation pit;

s55) paving a reinforcing mesh at the bottom of the end well foundation pit, and then pouring concrete with given thickness to the bottom of the end well foundation pit to complete the primary support construction of the end well foundation pit of the automatic footpath.

S56) performing waterproof construction, installing reinforcing steel bars and pouring concrete on the bottom and the wall of the end well foundation pit after primary support construction is completed in sequence, and completing end well construction.

Specifically, the preset grouting pressure value is 2 Mpa.

The invention provides a construction method of an end well of an automatic footpath, which is used for avoiding deformation and collapse of an underground passage structure when the end of the automatic footpath is constructed in the underground passage, after a construction area is determined in the underground passage, a plurality of vertical support columns are arranged at a given distance away from the construction area and supported between the ground and the top surface of the underground passage, a plurality of transverse support columns vertical to the construction area are arranged at a given height away from the construction area and supported between two side walls of the underground passage, the underground passage structure around the construction area is reinforced through the plurality of vertical support columns and the plurality of transverse support columns, the deformation and collapse of the underground passage structure when the end of the automatic footpath is constructed are prevented, after the vertical support columns and the transverse support columns are installed, a part to be cut on a rectangular pipe joint in the construction area is cut, and an end well guide pit is formed after the part to be cut on each rectangular pipe joint in the construction area is, and exposing the soil body to be excavated under the part to be cut, excavating a given depth along the depth direction of the end well guide pit to form an end well foundation pit, supporting the end well foundation pit, and finishing the construction of the end well of the automatic footpath.

According to the construction method of the end well of the automatic walkway, provided by the invention, before the construction of the end well, the underground passage structure around the construction area is reinforced in advance through the plurality of transverse supporting columns and the plurality of vertical supporting columns, so that the problems of deformation, collapse and the like of the underground passage structure when the end is constructed in the underground passage are avoided, the automatic walkway is ensured to complete the construction smoothly and safely, and convenience is provided for pedestrians to pass through the underground passage.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

fig. 1 is a flowchart of a method for constructing an end well of an automated walking path according to an embodiment of the present invention.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

In the present invention, unless specified to the contrary, use of the terms of orientation such as "upper, lower, top, bottom" or the like are generally described with respect to the orientation shown in the drawings or the positional relationship of the components with respect to each other in the vertical, or gravitational direction.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

An embodiment of the present invention provides a method for constructing an end well of an automatic walkway, where the end well of the automatic walkway is constructed in an underground passage formed by connecting a plurality of sections of rectangular pipe joints after pipe jacking construction, and fig. 1 is a flow chart of the method for constructing the end well of the automatic walkway, and as shown in fig. 1, the method for constructing the end well of the automatic walkway includes the following steps:

s1) lofting a construction area of a head well of the automatic walking way on the ground in the underground passage, and defining an area on each rectangular pipe joint surrounded by the construction area as a to-be-cut part;

s2) arranging a plurality of vertical supporting columns vertical to the ground at a given distance from the construction area, wherein two end faces of each vertical supporting column are respectively abutted against the ground and the top face of the underground passage;

s3) arranging a plurality of transverse supporting columns perpendicular to the vertical supporting columns at a given height above the construction area and perpendicular to the ground, wherein the end surfaces of two ends of each transverse supporting column are abutted against two side walls of the underground passage;

s4) cutting the to-be-cut part on each rectangular pipe joint to form an end well guide pit;

s5) excavating a given depth along the depth direction of the end well guide pit to form an end well foundation pit, supporting the end well foundation pit, and completing the construction of the end well of the automatic footpath.

The invention provides a construction method of an end well of an automatic footpath, which is characterized in that the end well is constructed in an underground passage formed after pipe jacking construction is finished, a construction area of the end well is firstly lofted on the ground in the underground passage, in order to prevent the structure of the underground passage from deforming and collapsing when the end well is constructed, a plurality of vertical support columns are arranged at a given distance of the construction area and supported between the ground and the top surface of the underground passage, a plurality of transverse support columns are arranged at a given height from the construction area and supported between two side walls above the construction area of the underground passage, the underground passage structure is reinforced by the plurality of vertical support columns and the plurality of transverse support columns, in order to further reinforce the underground passage structure, a plurality of support oblique columns are arranged between the ground and the side walls of the underground passage at the given distance from the construction area and between the top surface and the side walls so as to reinforce the support of the underground passage structure, and prevent the underground passage structure from deforming when, And (3) collapsing, after the vertical supporting columns and the transverse supporting columns are supported and reinforced, cutting a to-be-cut part on each rectangular pipe joint in the construction area, forming an end well guide pit after the to-be-cut part on the rectangular pipe joint in the construction area is cut, exposing a to-be-excavated soil body below the to-be-cut part, excavating a given depth along the depth direction of the end well guide pit according to the profile of the end well guide pit to form an end well foundation pit, supporting the end well foundation pit, and completing construction of the end well after supporting is completed.

In order to facilitate the construction of the end well, specifically, the to-be-cut part on the rectangular pipe joint is made of a steel plate. Before constructing the underground passage, when rectangular pipe sections in a construction area of the end well are manufactured, corresponding to-be-cut parts on the rectangular pipe sections are manufactured by adopting steel plates, the steel plates of the to-be-cut parts are connected with the rectangular pipe sections, and when the end well is constructed, the to-be-excavated soil body can be exposed by easily cutting off the to-be-cut parts to be connected with the rectangular pipe sections, so that the construction is convenient.

Before the end well excavation construction, the underground passage structure is reinforced by a plurality of vertical support columns and a plurality of transverse support columns, and in order to stably support the transverse support columns and the vertical support columns, the end well construction method of the automatic walkway further comprises the following steps: and pre-burying a plurality of base plates in the specified rectangular pipe joints before the step S1), wherein the two end surfaces of each vertical supporting column are respectively connected with the corresponding base plates to be abutted against the ground and the top surface of the underground passage, and the two end surfaces of each transverse supporting column are respectively connected with the corresponding base plates to be abutted against the two side walls of the underground passage. Bury the backing plate underground on the rectangle tube coupling in advance for backing plate and rectangle tube coupling become an organic whole, later horizontal support column and vertical support column are connected with the backing plate that corresponds separately, and it is more firm to support underground passage structure, because of being connected insecure with the backing plate in order to prevent horizontal support column and vertical support column, influence the supporting effect to underground passage, specifically, vertical support column with horizontal support column passes through welded fastening with the backing plate that corresponds separately.

When the end well is excavated, in order to prevent construction accidents such as collapse of soil around the end well in the excavation process, specifically, the end well construction method of the automatic sidewalk further includes:

and before the step S1), grouting the periphery of the soil body to be excavated of the end well of the automatic pavement to be excavated through the embedded grouting pipes on each rectangular pipe joint. Before the end well is excavated, grouting is carried out on the periphery of a soil body to be excavated to the end well through the grouting pipes pre-buried in the rectangular pipe joints, the soil body on the periphery of the soil body to be excavated is reinforced, the soil body on the periphery of the soil body to be excavated is prevented from collapsing when the end well is excavated, and the construction safety of the end well is ensured.

In order to ensure the safe construction of the end well, the method for constructing the end well of the automatic walkway further comprises the following steps:

sampling sample soil around a soil body to be excavated of an end well of the automatic walkway to be excavated through a preset sampling hole on the rectangular pipe joint, detecting the strength of the sample soil, and executing the step S4) after the strength of the sample soil reaches the preset strength, wherein the sampling hole is preset on the rectangular pipe joint, the sample soil around the soil body to be excavated of the end well of the automatic walkway to be excavated is sampled through the sampling hole, namely the sample soil around the soil body corresponding to a part to be cut on the rectangular pipe joint is sampled, the sampled soil body is ensured to have enough strength, the collapse is prevented from occurring when the end well of the automatic walkway is excavated, the unconfined compressive strength of the sample soil is not less than 1Mpa, and the permeability coefficient is not more than 1 × 10^-6And (4) excavating the end well under the condition of cm/s, and grouting reinforcement is needed under the condition that the unconfined compressive strength and permeability coefficient of the sample soil cannot meet the excavation requirement.

Specifically, step S5) of excavating a given depth in a depth direction of the end well guide pit perpendicular to the ground to form an end well foundation pit, supporting the end well foundation pit, and completing construction of an end well of the travelator includes:

s50) excavating towards the underground according to the profile of the end well guide pit until the excavation depth reaches a first depth to form a foundation pit section, installing a plurality of grid steel frames along the pit wall of the foundation pit section, and connecting adjacent grid steel frames by adopting connecting ribs;

s51) constructing a plurality of locking anchor pipes on the pit wall of the foundation pit section according to a given distance;

s52) spraying concrete with given thickness to the pit wall of the foundation pit section;

s53) grouting into the soil body around the foundation pit section through the anchor rods, wherein the grouting pressure is smaller than the preset grouting pressure value, and stopping grouting until grouting slurry is filled in the foot locking anchor pipes;

s54) repeating the steps S50) -S53) until the total depth of the multiple sections of foundation pit sections in the direction vertical to the ground reaches a given depth, and forming an end well foundation pit;

s55) paving a reinforcing mesh at the bottom of the end well foundation pit, and then pouring concrete with given thickness to the bottom of the end well foundation pit to complete the primary support construction of the end well foundation pit of the automatic footpath.

S56) performing waterproof construction, installing reinforcing steel bars and pouring concrete on the bottom and the wall of the end well foundation pit after primary support construction is completed in sequence, and completing end well construction.

In one embodiment, an end well is constructed in the underground passage, the end well comprises an equipment well with the length of 6.3m, the width of 3.65m and the depth of 0.58m and a water collecting well with the length of 2.8m, the width of 3.65m and the depth of 2.35m, and the equipment well and the water collecting well are positioned in the end well, so that the equipment well and the water collecting well are constructed simultaneously; the method comprises the steps of forming an end well guide pit after cutting a cutting part on a rectangular pipe joint, excavating towards the underground according to the outline of the end well guide pit, excavating the middle part of the end well firstly during excavation, excavating surrounding well walls in sections, adopting an excavation mode of excavating and supporting at the same time during the excavation process, namely supporting a formed foundation pit section at a first depth every time of excavation, preventing soil from collapsing during the excavation process, removing virtual slag and other sundries on the pit wall of the foundation pit section after the excavated foundation pit section is formed, installing grid steel frames along the pit wall of the foundation pit section, connecting adjacent grid steel frames by adopting connecting ribs, and then constructing a plurality of grids on the pit wall of the foundation pit sectionThe interval of the lock pin anchor pipes in the circumferential direction of the foundation pit section is 1m, the displacement of a grid steel frame on the pit wall of the foundation pit section can be limited through a plurality of lock pin anchor pipes arranged on the pit wall of the foundation pit section, so that the grid steel frame can bear the pressure applied by surrounding rocks around the foundation pit section as early as possible, the stability of the formed foundation pit section is ensured, after the anchor rods are arranged, concrete is sprayed on the pit wall of the foundation pit section in multiple times, the given thickness of the sprayed concrete is 360mm, 1:1 cement grout is injected into soil around the foundation pit section through the lock pin anchor pipes after the concrete is sprayed, the grouting pressure value is smaller than the preset grouting pressure value of 2MPa, the grouting is stopped after the lock pin anchor pipes are filled with the grouting grout, and the steps are repeated until the grouting is directly reached to the soil around the foundation pit sectionThe total depth reaches the given depth of the equipment well and the water collecting well, an end well foundation pit is formed, then a reinforcing mesh is laid at the bottom of an end well foundation pit, concrete with the given thickness is poured at the bottom of the end well foundation pit with the reinforcing mesh laid, the primary support construction of the end well is completed, waterproof construction is carried out on the bottom of the end well foundation pit and the pit wall, reinforcing steel bars are installed on the bottom of the pit and the pit wall which are jointed to complete the waterproof construction to form a reinforcing steel bar framework, a steel die is installed in the end well foundation pit, the reinforcing steel bar framework is wrapped by the poured concrete, the construction of the end well is completed after the concrete is solidified, and the construction of the water collecting well and the equipment well.

The invention provides a construction method of an end well of an automatic footpath, which is used for avoiding deformation and collapse of an underground passage structure when the end of the automatic footpath is constructed in the underground passage, after a construction area is determined in the underground passage, a plurality of vertical support columns are arranged at a given distance away from the construction area and supported between the ground and the top surface of the underground passage, a plurality of transverse support columns vertical to the construction area are arranged at a given height away from the construction area and supported between two side walls of the underground passage, the underground passage structure around the construction area is reinforced through the plurality of vertical support columns and the plurality of transverse support columns, the deformation and collapse of the underground passage structure when the end of the automatic footpath is constructed are prevented, after the vertical support columns and the transverse support columns are installed, a part to be cut on a rectangular pipe joint in the construction area is cut, and an end well guide pit is formed after the part to be cut on each rectangular pipe joint in the construction area is, and exposing the soil body to be excavated under the part to be cut, excavating a given depth along the depth direction of the end well guide pit to form an end well foundation pit, supporting the end well foundation pit, and finishing the construction of the end well of the automatic footpath.

According to the construction method of the end well of the automatic walkway, provided by the invention, before the construction of the end well, the underground passage structure around the construction area is reinforced in advance through the plurality of transverse supporting columns and the plurality of vertical supporting columns, so that the problems of deformation, collapse and the like of the underground passage structure when the end is constructed in the underground passage are avoided, the automatic walkway is ensured to complete the construction smoothly and safely, and convenience is provided for pedestrians to pass through the underground passage.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.