CN220395699U - Distance-adjustable shield reaction frame beam structure - Google Patents

Abstract

The utility model provides a distance-adjustable shield reaction frame cross beam structure. The first box cross beam and the second box cross beam are hollow structures with square sections, the two box cross beams are welded to form an integral cross beam after being butted, the two length adjusting plates are symmetrically arranged on the inner sides of the box cross beams, and each length adjusting plate extends from the first box cross beam to the second box cross beam and is fixedly connected with the side plates of the first box cross beam and the second box cross beam through fastening bolts; the hollow areas of the first box cross beam and the second box cross beam are provided with supporting plates, and the bottoms of the first box cross beam and the second box cross beam are respectively provided with connecting plates. The utility model has larger and more flexible size adjustment interval, and meets the size requirements of shield starting reaction frames with different diameters to a certain extent, thereby meeting the purpose of repeated use; and the strength of the whole cross beam can meet the use requirement of the shield reaction frame.

Description

Distance-adjustable shield reaction frame beam structure

Technical Field

The utility model belongs to the field of steel structure design, and particularly relates to a distance-adjustable shield reaction frame cross beam structure.

Background

The construction and construction of tunnels in subways generally adopts a shield method, and the shield is started and separated from a reaction frame to serve as a starting support, so that the control on the construction process is required to be enhanced in the process of shield starting and receiving and construction, and the construction of an underground space traffic network is ensured to be efficiently and safely propelled. The reaction frame provides reaction for the shield in the shield starting process, the applicability of the traditional shield reaction frame is single, the diameter of each type of reaction frame is fixed and used for one-time shield starting, and when shields with other diameters start, the reaction frame needs to be manufactured again, so that the labor and the material are wasted to a certain extent.

Because the control of the counter-force frame on the diameter is mainly embodied on the adjustment of the size of the cross beam, the problems are comprehensively solved, the size of the cross beam of the counter-force frame can be freely adjusted, and the counter-force frame can be repeatedly used for many times under the conditions of strength, rigidity and stability, so that certain economic benefits are realized.

Disclosure of Invention

In order to solve the defects of the prior art and achieve the purposes, the utility model provides the distance-adjustable shield reaction frame beam structure, which has a larger and more flexible size adjustment interval, and meets the size requirements of shield starting reaction frames with different diameters to a certain extent, so that the purpose of repeated use is fulfilled.

In order to achieve the above purpose, the utility model provides a distance-adjustable shield reaction frame beam structure, which comprises a first box beam, a second box beam and a length adjusting plate, wherein the first box beam and the second box beam are hollow structures with square sections, the two box beams are welded to form an integral beam after being butted, the two length adjusting plates are symmetrically arranged on the inner sides of the box beams, and each length adjusting plate extends from the first box beam to the second box beam and is fixedly connected with side plates of the first box beam and the second box beam through fastening bolts; the hollow areas of the first box cross beam and the second box cross beam are provided with supporting plates, and the bottoms of the first box cross beam and the second box cross beam are respectively provided with connecting plates.

The utility model has the preferable technical scheme that: the first box body cross beam and the second box body cross beam are formed by encircling two vertical support plates and two transverse support plates, the two transverse support plates are positioned between the two vertical support plates and welded with the two vertical support plates, a plurality of rib plates are arranged on the outer side of each transverse support plate, and two sides of each rib plate are welded with the two vertical support plates;

the utility model has the preferable technical scheme that: the length of the length adjusting plate is larger than that of a single box body cross beam and smaller than or equal to the total length of two box body cross beams; the upper edge and the lower edge of each length adjusting plate are fixedly pressed by L-shaped pressing plates, the L-shaped pressing plates are welded at the inner corners of the box body cross beam, and in a fastening bolt loosening state, the length adjusting plates are horizontally moved and adjusted along the upper L-shaped pressing plates and the lower L-shaped pressing plates.

The utility model has the preferable technical scheme that: two connecting plates are symmetrically arranged at the middle parts of the bottom plates of the first box body cross beam and the second box body cross beam, and a plurality of threaded holes are formed in each connecting plate.

The utility model has the preferable technical scheme that: the vertical support plates, the transverse support plates, the rib plates and the length adjusting plates adopt S355N weldable fine grain structure steel plates; its mass density is 7800kg/m ³ Modulus of elasticity 2.1X10 ¹¹ N/m ² Poisson's ratio 0.28, specific heat 440J (kg·k), thermal conductivity 14W/(m·k).

The utility model has the preferable technical scheme that: the length adjusting plates and the two vertical supporting plates are uniformly distributed with a plurality of bolt holes, and the length adjusting plates are matched with the bolt hole arrangement intervals on the vertical supporting plates; the fastening bolt adopts a high-strength countersunk head screw and is fixedly locked through a washer type hexagonal nut.

The utility model has the preferable technical scheme that: the backup pad is equipped with the polylith, every two alternately dispersedly set up in the cavity region of first box crossbeam and second box crossbeam, and the both ends of every backup pad weld respectively on L type clamp plate.

The utility model has the preferable technical scheme that: the L-shaped pressing plate adopts hot-rolled equilateral angle steel, is selected from GB9787-1988 materials, and has a mass density of 7800kg/m ³ Modulus of elasticity 2.1X10 ¹¹ N/m ² Poisson's ratio 0.28, specific heat 440J (kg·k), thermal conductivity 14W/(m·k).

The utility model has the preferable technical scheme that: the high-strength countersunk head screw is selected from GB/T5782-2016M30; the washer-type hexagonal nut is selected from GB/T6167-2000.

When the utility model is used for adjusting, the side plates of the welding parts of the first beam box body and the second beam box body are cut only through thermal cutting, the high-strength countersunk head screw and the washer-type hexagonal nut are disassembled, and the length adjusting block is pulled to adjust to the size and the position required by engineering, so that the size adjustment of the beam is completed. The utility model has larger and more flexible size adjustment interval, and meets the size requirements of shield starting reaction frames with different diameters to a certain extent, thereby meeting the purpose of repeated use; and the strength of the whole cross beam can meet the use requirement of the shield reaction frame.

Drawings

FIG. 1 is a schematic view of the overall structure of the present utility model;

FIG. 2 is an enlarged schematic view of a single box girder of the present utility model;

FIG. 3 is a cross-sectional view of a box girder of the present utility model;

FIG. 4 is a schematic view of the internal structure of the cross beam of the box body of the utility model;

FIG. 5 is a front view of the cross beam of the box of the present utility model in use;

fig. 6 is a perspective view showing a state in which the case cross member of the present utility model is used.

In the figure: 1-first box crossbeam, 2-gusset, 3-fastening bolt, 4-second box crossbeam, 5-backup pad, 6-connecting plate, 600-screw hole, 7-length adjustment board, 8-L clamp plate, 9-sloping, 10-vertical beam.

Detailed Description

The utility model is further described below with reference to the drawings and examples. Figures 1 through 6 are drawings of embodiments, which are drawn in a simplified manner, for the purpose of illustrating embodiments of the utility model in a clear and concise manner. The following technical solutions presented in the drawings are specific to embodiments of the present utility model and are not intended to limit the scope of the claimed utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the present utility model, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "inner", "outer", "left", "right", etc. are based on the directions or positional relationships shown in the drawings, or the directions or positional relationships conventionally put in place when the inventive product is used, or the directions or positional relationships conventionally understood by those skilled in the art are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific direction, be configured and operated in a specific direction, and therefore should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

In the description of the present utility model, it should also be noted that, unless explicitly specified and limited otherwise, terms such as "disposed," "connected," and the like are to be construed broadly, and for example, "connected" may be either fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

The embodiment provides a but distance-adjusting shield reaction frame crossbeam, as shown in fig. 1 to 4, crossbeam structure first box crossbeam 1, second box crossbeam 4 and length adjustment board 7, first box crossbeam 1 and second box crossbeam 4 are the hollow structure that the cross-section is square, and weld after two box crossbeams butt joint and form an integral crossbeam, first box crossbeam 1 and second box crossbeam 4 are enclosed by two vertical support plates 100 and two horizontal support plates 101 and are formed, and two horizontal support plates 101 are located between two vertical support plates 100 to weld with two vertical support plates 100, are equipped with polylith gusset 2 in every horizontal support plate 101 outside, and the both sides and the two vertical support plates 100 welding of every gusset 2. The support plate 5 is arranged in the hollow area of the first box beam 1 and the second box beam 4, the connecting plates 6 are respectively arranged at the bottoms of the first box beam 1 and the second box beam 4, the two connecting plates 6 are symmetrically arranged at the middle parts of the bottom plates of the first box beam 1 and the second box beam 4, a plurality of threaded holes 600 are formed in each connecting plate 6, and the connecting plates 6 are used for being connected with other beams of the shield reaction frame.

The embodiment provides a distance-adjustable shield reaction frame beam, as shown in fig. 1 to 4, two length adjusting plates 7 are symmetrically arranged on the inner side of a box beam, and the length of each length adjusting plate 7 is greater than the length of a single box beam and less than or equal to the total length of two box beams; each length adjusting plate 7 extends from the first box beam 1 to the second box beam 4 and is fixedly connected with the side plates of the first box beam 1 and the second box beam 4 through fastening bolts 3; the upper edge and the lower edge of each length adjusting plate 7 are fixedly pressed by an L-shaped pressing plate 8, the L-shaped pressing plates 8 are welded at the inner corners of the box body cross beam, and the length adjusting plates 7 are horizontally moved and adjusted along the upper L-shaped pressing plates and the lower L-shaped pressing plates in a state that the fastening bolts 3 are loosened; the L-shaped pressing plate 8 can restrict the length adjusting plate 7 from moving up and down. The length adjusting plates 7 and the two vertical supporting plates 100 are uniformly and dispersedly provided with a plurality of bolt holes, and the length adjusting plates 7 are matched with the bolt hole arrangement intervals on the vertical supporting plates 100; the fastening bolt 3 is a high Jiang Chentou screw and is fixedly locked by a washer-type hexagonal nut. The supporting plates 5 are provided with a plurality of blocks, every two of the supporting plates are arranged in the hollow areas of the first box body cross beam 1 and the second box body cross beam 4 in a scattered mode, and two ends of each supporting plate 5 are welded on the L-shaped pressing plates 8 respectively.

The embodiment provides a distance-adjustable shield reaction frame cross beam, wherein the vertical support plate 100, the horizontal support plate 101, the rib plates 2 and the length adjusting plate 7 adopt S355N weldable fine grain structure steel plates; its mass density is 7800kg/m ³ Modulus of elasticity 2.1X10 ¹¹ N/m ² Poisson's ratio 0.28, specific heat 440J (kg·k), thermal conductivity 14W/(m·k). The L-shaped pressing plate 8 adopts hot-rolled equilateral angle steel and is selected from GB9787-1988 materials, and the mass density of the L-shaped pressing plate is 7800kg/m ³ Modulus of elasticity 2.1X10 ¹¹ N/m ² Poisson's ratio 0.28, specific heat 440J (kg·k), thermal conductivity 14W/(m·k). The high-strength countersunk head screw is selected from GB/T5782-2016M30; the washer-type hexagonal nut is selected from GB/T6167-2000.

The method for manufacturing and welding the beam structure of the distance-adjustable shield reaction frame is further described below with reference to specific embodiments, and specifically comprises the following steps:

(1) Cutting and blanking the S355N weldable fine grain structure steel plate by a flame cutting machine to manufacture a vertical supporting plate 100, a transverse supporting plate 101, a rib plate 2, a connecting plate 6 and a length adjusting plate 7; S355N, blanking and cutting of the weldable fine grain structure steel plate are performed by a flame/plasma cutting machine. The whole length of the counter-force frame beam is recorded as L (mm), the height is H (mm), the plate thickness is D (mm), and the length, the height and the thickness are actually selected according to specific engineering; S355N weldable fine grain structure steel plates are processed by a flame/plasma cutting machine to be manufactured into 4 vertical support plates with the length of L/2, the height of H (mm) and the thickness of D (mm); and marking the width of the transverse supporting plate as B (mm), wherein the B (mm) is selected according to engineering practice, the S355N weldable fine grain structure steel plate is manufactured into 4 transverse supporting plates with the length of L (mm), the width of B (mm), the thickness of D (mm) and the groove angle of 45 degrees, and the groove depth of 0.8D (mm) by adopting a flame/plasma cutting machine. The length of the rib plate 2 is B-2D (mm), the thickness is D (mm), the rib plate 2 is a double-side groove, the angle is 45 degrees, and the groove depth is 0.45D (mm). The length adjustment block 7 had a length of 0.8L (mm), a height of H (mm) and a plate thickness of D (mm). The connecting plate 6 is C (mm) long, B-2D (mm) wide, D (mm) thick, double-sided grooves with an angle of 45 degrees and groove depth of 0.65D (mm). 4 hot rolled equilateral angle steels with a length of 0.8L (mm) were cut as L-shaped press plates 8.

(2) Punching the vertical support plate 100, the connecting plate 6 and the length adjusting plate 7 by adopting a machine tool; placing the vertical support plate 100 with the manufactured blanking in the two wedge-shaped parts to cut into the space between the clamping piece and the connecting steel plate according to a positive direction and a negative direction, so that the connecting steel plate is firmly fixed; the drilling machine is located on a base steel plate, the angle of the drilling machine is adjusted, then drilling operation is carried out on the vertical supporting plate 100, holes are drilled at intervals of 300 mm/each, and the total number of holes is L/600; drilling holes with the length of 0.8L (mm), the height of H (mm) and the plate thickness of D (mm) according to the hole spacing of 300 mm/each, wherein the total number of the holes is L/600; the connecting plate 6 with the length of C (mm), the width of B-2D (mm), the thickness of D (mm), the bilateral groove, the angle of 45 degrees and the groove depth of 0.65D (mm) is drilled according to the hole spacing of 100mm, the edge spacing of 40mm and the diameter of 33 mm.

(3) Then assembling and welding all the plates according to the drawing; positioning is performed before welding, a reference position is positioned on a welding platform according to the size of the plate, a center line is drawn, and a positioning block with a corresponding height is placed, so that the welding platform is required to be kept horizontal. The method specifically comprises the following steps: firstly, 1 transverse supporting plate 101 is fixed on a positioning block of a welding platform according to positioning, then a vertical supporting plate 100 is placed perpendicular to the transverse supporting plate 101, so that the transverse supporting plate 101 is overlapped with the vertical supporting plate 100, then three sides of the vertical supporting plate 100 and the transverse supporting plate 101 are welded, the welding process is repeated, 2 sections of welded cross beam boxes are welded, after the welding process is completed, 2 hot-rolled equilateral angle steels are welded to two corner points at the bottom of the box body according to the positioning of a drawing, a length adjusting plate is inserted, and a box body reinforcing rib plate and the hot-rolled equilateral angle steels are welded according to the groove.

(4) Finally, the welded box body is punched with a strength hexagon bolt, a threaded hole in a length adjusting plate 7 in the welded three-face edge sealing box body is aligned with a threaded hole of a vertical supporting plate 100, a high-strength countersunk head screw is inserted, and a washer type hexagon nut is used for fixing; and then placing the transverse supporting plate 101 on the three-face box body which is welded and manufactured for closed welding to complete the whole box body manufacturing, welding the transverse rib plates at two ends of the box body every 2m, and finally welding the connecting plate 6 on the box body according to the drawing to complete the whole box body manufacturing.

Rivet welding is adopted in the welding mode in the embodiment; the form and the size of the groove of the welded groove are in accordance with

Recommended grooves of GB/T985.1-2008 gas welding, welding rod arc welding, gas shielded welding and high-energy beam welding, but a blunt edge with a certain size must be reserved, the blunt edge size of a single-sided groove is less than or equal to 2mm, and the blunt edge size of a double-sided groove is less than or equal to 2 mm; the surface of the groove is polished to be smooth and clean, oil stain, rust, dust and obvious cutting marks or defects cannot exist, and impurities harmful to welding such as oxide scales, carbides, grease, water, paint and the like are removed, so that the natural color of the metal can be seen; if the groove surface is provided with a larger groove, the groove surface must be polished and deposited and polished. The weld and the surface close to the weld must be kept clean, and no oxide scale, scrap iron, greasy dirt, rust, dust and obvious cuts or defects exist; the spot welding length cannot be lower than 40mm, the spot welding only plays a role in temporary fixation, and if the filling welding is affected, the spot welding should be removed; if the intermittent welding line for fixing the parts is defective, the intermittent welding line must be polished and cleaned before welding can be performed on the intermittent welding line.

When all steel structures are manufactured by welding, the welding seam with the thickness of the base metal exceeding 40mm is required to be preheated; a proper thermometer must be used to detect the preheating temperature, the detection range includes the area of about 100mm on each side of the weld; the preheating temperature is generally 120-150 ℃, and if the welding is continuously carried out, the preheating is not needed; if the middle is stopped, such as after noon break, the preheating is needed again; it should be noted that, when the support leg is assembled and welded with the cutter head steel structure, the support leg must be preheated and heat must be preserved after welding.

When the high-strength bolt is installed in the embodiment, burrs and the like are removed, the friction surface is kept dry, the operation in the rain is not required, the high-strength bolt is penetrated by a method of driving a punching nail, and reaming of a reamer is forbidden. When the individual bolt hole is to be reamed, a reamer is used for trimming the hole, and the maximum diameter of the trimmed hole is smaller than 1.2 times of the diameter of the bolt. And all the bolts around are screwed up before reaming, so that the plates are overlapped and closely adhered. To prevent scrap iron from falling into the plate stack seam. And (5) strictly forbidding gas cutting reaming. After the hole is repaired, a grinder is used for removing burrs at the edge of the hole, grinding wheel scraps are cleaned, and when the high-strength bolt is screwed, only torque is allowed to be applied to the nut.

When the adjustable distance shield reaction frame cross beam of the support in the embodiment is used, as shown in fig. 5 and 6, the whole reaction frame can be manufactured by welding with the existing vertical support and the existing inclined support. When the diameter is required to be adjusted, the L/2-position beam inner side plate and the beam outer side plate are cut only through thermal cutting, the high-strength countersunk head screw is disassembled, the washer-type hexagonal nut is pulled to adjust the length adjusting block to the size and the position required by engineering, and the size adjustment of the beam is completed.

The prepared distance-adjustable shield reaction frame cross beam is applied to the following steps:

application example one: taking a spike and guan deep project reaction frame as an example, a cross beam, a vertical beam and an inclined beam are all flange and bolt connection for a box beam structure of a steel plate surrounding city with the thickness of 30mm, and according to the structural condition of a rear pilot tunnel, the support of the reaction frame is a steel pipe horizontal support with the horizontal support of 600x12mm and provides a reaction force for shield initiation with the diameter of 8.8m on the rear pilot tunnel structure. The counter-force frame cross beam is manufactured in the mode of the utility model to adjust the length and the size.

And verifying the mechanical finite element of the application example I: the support is distributed in a manner of being sparse at the upper part and dense at the lower part; the stress is divided into 6 areas according to the thrust of the shield machine, namely, a lower area 1700t, left and right lower areas respectively 650t, left and right upper areas respectively 400t, the upper area is 200t, the total thrust is 4000t, and the thrust is transmitted to a reaction frame through a negative ring pipe piece. The reaction frame material Q345, the allowable stress of the material 345Mpa, the actual calculated stress is 297Mpa, and the maximum stress appears at the position of the horizontal support.

The safety coefficient is as follows: 345/297 = 1.162. The safety factor of the pressed structure is low, so the design meets the safety requirement. Displacement: 6.9mm, also within the allowed displacement range.

Application example two: the counter-force frame of the slurry shield with the length of 12m of the pool project is made of Q345 material, the inclined strut is made of 600x20mm steel pipes, the horizontal short support is stressed greatly at the lower part, and a plurality of 600x30mm steel pipes are adopted. The steel plate which is pre-buried in the rear guide table and is perpendicular to the axis of the inclined strut steel pipe is pre-buried in advance, the inclined shearing force is changed into axial pressure, the horizontal short support is stressed greatly at the lower part, and the length and the size are adjusted by adopting the steel pipe counter-force frame cross beam with the thickness of 600x30 mm. The stress of the reaction frame is more stable.

And verifying the mechanical finite element of the application example II: the thrust is distributed according to 6 partitions of the actual starting point, 1600t of thrust is arranged at the lowest part, 1200t total 2400t is arranged at the left and right lower parts, 700t total 1400t is arranged at the left and right upper parts, 400t is arranged at the uppermost part, and the total thrust is 5800t.

The result of the stress finite element analysis of the design is shown in the figure, the material Q345 is used, the allowable stress is 345Mpa, the actually calculated maximum stress is 301Mpa, and the stress is present at the position of the cross beam, belongs to the stress singular point and can not be adopted.

Safety factor: 345/301=1.15, should be a pressed structure, and the structural strength is safe.

Maximum displacement: 27mm, is within a safe displacement range relative to a shield diameter of 12 m.

Application example three: taking a wide-flowered inter-city large shield starting reaction frame as an example, using a box girder which is made of materials Q345 and has the thickness of 30mm and 40mm, wherein the bottom is a concrete arc guide table, an inclined strut is a steel pipe with the thickness of 600x12mm, the upper end is welded with a flange plate of a triangular box body of the reaction frame, the lower end is welded with a flange plate embedded in concrete, the two ends are vertically pressed, the damage of shearing force to the structure is avoided, and the steel pipe reaction frame cross beam is manufactured in the mode of the utility model to adjust the length and the size, so that the whole structure is more stable.

And verifying the mechanical finite element of the application example III: a box girder structure made of steel plates with the thickness of 30mm and 40mm is used, allowable stress is 345Mpa, maximum thrust is set to 6000t, and calculated maximum stress is 253.1Mpa.

Safety factor: 345/253.1=1.36, the compressed structure meets the safety standards.

Maximum displacement: 9.5mm, 9.5mm being an acceptable deformation range in the case of a total reaction frame size of 13 m.

Through finite element analysis verification in the application example, the adjustable distance shield reaction frame beam has good mechanical property.

It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the utility model and is not intended to limit the utility model, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the utility model are intended to be included within the scope of the utility model.

Claims (9)

1. A distance-adjustable shield reaction frame beam structure is characterized in that: the novel box body comprises a first box body cross beam (1), a second box body cross beam (4) and a length adjusting plate (7) which are of a cross beam structure, wherein the first box body cross beam (1) and the second box body cross beam (4) are hollow structures with square sections, the two box body cross beams are welded to form an integral cross beam after being butted, the length adjusting plate (7) is provided with two pieces and is symmetrically arranged on the inner side of the box body cross beam, and each length adjusting plate (7) extends from the first box body cross beam (1) to the second box body cross beam (4) and is fixedly connected with side plates of the first box body cross beam (1) and the second box body cross beam (4) through fastening bolts (3); the hollow areas of the first box body cross beam (1) and the second box body cross beam (4) are provided with supporting plates (5), and the bottoms of the first box body cross beam (1) and the second box body cross beam (4) are respectively provided with connecting plates (6).

2. The adjustable distance shield reaction frame beam structure according to claim 1, wherein: the first box cross beam (1) and the second box cross beam (4) are formed by enclosing two vertical support plates (100) and two horizontal support plates (101), the two horizontal support plates (101) are located between the two vertical support plates (100) and welded with the two vertical support plates (100), a plurality of rib plates (2) are arranged on the outer side of each horizontal support plate (101), and two sides of each rib plate (2) are welded with the two vertical support plates (100).

3. The adjustable shield reaction frame beam structure according to claim 1 or 2, wherein: the length of the length adjusting plate (7) is larger than the length of a single box body cross beam and smaller than or equal to the total length of two box body cross beams; the upper edge and the lower edge of each length adjusting plate (7) are fixedly pressed by an L-shaped pressing plate (8), the L-shaped pressing plates (8) are welded at the inner corners of the box body cross beam, and in the loosening state of the fastening bolts (3), the length adjusting plates (7) are horizontally moved and adjusted along the upper L-shaped pressing plates and the lower L-shaped pressing plates.

4. The adjustable shield reaction frame beam structure according to claim 1 or 2, wherein: two connecting plates (6) are symmetrically arranged at the middle parts of the bottom plates of the first box body cross beam (1) and the second box body cross beam (4), and a plurality of threaded holes (600) are formed in each connecting plate (6).

5. The adjustable distance shield reaction frame beam structure according to claim 2, wherein: the vertical support plates (100), the transverse support plates (101), the rib plates (2) and the length adjusting plates (7) adopt S355N weldable fine grain structure steel plates; its mass density is 7800kg/m ³ Modulus of elasticity 2.1X10 ¹¹ N/m ² Poisson's ratio 0.28, specific heat 440J (kg·k), thermal conductivity 14W/(m·k).

6. The adjustable distance shield reaction frame beam structure according to claim 2, wherein: the length adjusting plates (7) and the two vertical supporting plates (100) are uniformly distributed with a plurality of bolt holes, and the length adjusting plates (7) are matched with the bolt hole arrangement intervals on the vertical supporting plates (100); the fastening bolt (3) adopts a high-strength countersunk head screw and is fixedly locked through a washer type hexagonal nut.

7. A distance-adjustable shield reaction frame beam structure according to claim 3, characterized in that: the support plates (5) are provided with a plurality of blocks, every two of the support plates are arranged in the hollow areas of the first box body cross beam (1) and the second box body cross beam (4) in a scattered mode, and two ends of each support plate (5) are welded on the L-shaped pressing plate (8) respectively.

8. A distance-adjustable shield reaction frame beam structure according to claim 3, characterized in that: the L-shaped pressing plate (8) adopts hot-rolled equilateral angle steel, is selected from GB9787-1988 materials, and has a mass density of 7800kg/m ³ Modulus of elasticity 2.1X10 ¹¹ N/m ² Poisson's ratio 0.28, specific heat 440J (kg·k), thermal conductivity 14W/(m·k).

9. The adjustable shield reaction frame beam structure of claim 6, wherein: the high-strength countersunk head screw is selected from GB/T5782-2016M30; the washer-type hexagonal nut is selected from GB/T6167-2000.