A D-type temporary beam line reinforcement method and reinforcement structure under complex geological conditions

Abstract

The present invention provides a D-type temporary beam line reinforcement method and reinforcement structure under complex geological conditions. Addressing the difficulty of line reinforcement in high-water-level, quicksand, and soft soil, the invention employs a "support wall" instead of the traditional "manually bored pile" method for supporting D-type temporary beams. This method addresses the significant safety risks associated with traditional D-type temporary beam reinforcement methods in complex geological conditions such as high water levels and quicksand. This reduces construction safety risks and ensures safe operation on operating lines. This invention relates to the field of railway engineering.

Description

Technical Field

[0001] The invention relates to a D-type temporary beam line reinforcement method and reinforcement structure under complex geological conditions, and belongs to the field of railway engineering. Background Art

[0002] Most railway electrification projects involve the construction of frame bridge jacking. Line reinforcement is a key step in this process. Under complex geological conditions such as high water levels and quicksand and soft soil, the traditional method of using "manual bored piles" to support D-type temporary beams to reinforce the line presents a significant safety risk. Reducing the construction safety risks of line reinforcement in poor geological conditions and ensuring driving safety on operating lines is a current challenge. Summary of the Invention

[0003] The present invention provides a D-type temporary beam line reinforcement method and reinforcement structure under complex geological conditions to solve the problem that the traditional method of supporting D-type temporary beams to reinforce lines has great safety risks under complex geological conditions such as high water levels and quicksand and soft soil.

[0004] In order to solve the above problems, a D-type temporary beam line reinforcement method under complex geological conditions is proposed. The specific steps are as follows:

[0005] 1) Construction of temporary buttresses;

[0006] 2) Construct the first and second D temporary beams on the temporary piers to reinforce the track simultaneously. After the line is elevated, excavate below the middle of the first and second D temporary beams to the design elevation for base reinforcement. The reinforcement method is to insert I-beams into the base high-pressure jet grouting piles. Leave 50 cm above the base high-pressure jet grouting piles to embed the I-beams into the bottom of the supporting wall.

[0007] 3) Support wall construction: After the base reinforcement is completed, a support wall is constructed above the high-pressure jet grouting piles on the base. The support wall adopts a reinforced concrete structure, and settlement observation points are set on the support wall. The reserved part of the base I-beam is embedded in the bottom of the support wall;

[0008] 4) Backfill: backfill after the support wall construction is completed and reaches the design strength;

[0009] 5) Remove the first and second D-type temporary beams and erect the third D-type temporary beam. The third D-type temporary beam is set along the line direction, and the two ends of the third D-type temporary beam are respectively erected on two supporting strong points. The line is overhead, and the earthwork of the jacking section is excavated to carry out the jacking construction of the frame bridge;

[0010] 6) Line settlement observation: Strictly implement the settlement observation system throughout the construction process to prevent the settlement of existing lines from endangering personal and driving safety.

[0011] In the above 1), while constructing the temporary pier 1, jet grouting piles are constructed in parallel along the circumference of the line reinforcement area. For the construction of the operating line, it is not possible to forcibly pump out water on a large scale. However, in some construction sites where the groundwater level is relatively high, double rows of high-pressure jet grouting piles (jet grouting piles) are used as curtain waterstops in the line reinforcement area. I-steels are inserted into the inner curtain piles to provide support during the jacking process. After the jet grouting piles are constructed, local dewatering is carried out to provide the prerequisite for subsequent construction. While dewatering, temporary piers for the D-shaped temporary beams are constructed.

[0012] In the above reinforcement method, the jet grouting piles are double-row high-pressure, with a diameter of 0.7m, a length of 10.5m, a spacing of 0.5m, and an engagement of 0.2m. The inner jet grouting piles are inserted into the Ⅰ20 I-beam and serve as a support at the same time.

[0013] In the aforementioned reinforcement method, three temporary piers are distributed and constructed along the line direction in the line reinforcement area, the first D temporary beam and the second D temporary beam are sequentially connected along the line direction, and the ends of the first D temporary beam and the second D temporary beam are respectively erected on the three temporary piers;

[0014] In the above 3), the base high-pressure rotary jet grouting piles are 5φ0.7m, 10.62m long, and arranged in 5 rows longitudinally with a spacing of 0.2m. The three inner rows of piles are constructed as interlocking piles, and I20 I-beams are inserted into the base high-pressure rotary jet grouting piles at the bottom of the design position of the supporting wall.

[0015] The present invention also provides a D-type temporary beam line reinforcement structure under complex geological conditions, including temporary piers, jet grouting piles, a first D temporary beam, a second D temporary beam and a supporting wall. The jet grouting piles are arranged along the circumference of the line reinforcement area to form a water-stop curtain. Three temporary piers are distributed and arranged in the line reinforcement area at equal intervals along the line. The first D temporary beam and the second D temporary beam are used to be arranged in sequence along the line direction and erected on the three temporary piers to temporarily support the existing line. Support walls are respectively arranged below the middle of the first D temporary beam and the second D temporary beam. The base high-pressure jet grouting piles are arranged at the bottom of the supporting wall to support the supporting strong. The third D temporary beam is used to be arranged along the line direction and erected on two supporting strong at both ends to support the line above the frame bridge to be constructed.

[0016] Compared with the existing technology, the present invention adopts "support wall" to carry out line reinforcement construction as the construction plan within the B / C of the operating line (construction throughout the day). Compared with the traditional "manual bored piles", which require the operating line level III construction plan, it avoids the tight construction period of only 2 to 3 hours of work per day. Its construction period is only about 60% of the traditional manual digging. When using "support wall" for line reinforcement, it can meet the complex geological conditions of high water level quicksand and soft soil. Compared with the traditional "manual bored piles" that are "easy to collapse" under such conditions, it is safer and effectively protects personal and driving safety. Compared with the traditional "manual bored piles", the present invention does not require manual digging under high water level and quicksand and soft soil conditions. The use of "support wall" can play the role of supporting load, stopping water, retaining soil, etc., reducing safety risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a plan view schematic diagram of the present invention;

[0018] Figure 2 yes Figure 1 Cross-sectional view of the temporary buttress, the first D temporary beam and the second D temporary beam under construction in the AA direction;

[0019] Figure 3 yes Figure 1 Sectional view of the AA direction during construction of the third D temporary beam;

[0020] Figure 4 yes Figure 3 Cross-sectional view along the BB direction;

[0021] Figure 5 yes Figure 3 Cross-sectional view in CC direction DETAILED DESCRIPTION

[0022] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0023] Example

[0024] Refer to the attached Figures 1 to 5 This embodiment provides a D-type temporary beam line reinforcement method under complex geological conditions. The specific steps are as follows:

[0025] 1) Construct temporary buttress 1 and simultaneously construct jet grouting piles 2 along the circumference of the line reinforcement area. The jet grouting piles 2 are double-row high-pressure, with a diameter of 0.7m, a length of 10.5m, a spacing of 0.5m, and an interlock of 0.2m. The inner jet grouting piles 2 are inserted into Ⅰ20 I-steels to provide support during the jacking process. After the jet grouting piles are completed, local precipitation is carried out to provide prerequisites for subsequent construction.

[0026] 2) Construct the first D temporary beam 3 and the second D temporary beam 4 on the temporary pier 1 to reinforce the track at the same time. Three temporary piers 1 are distributed and constructed in the line reinforcement area along the line direction. The first D temporary beam 3 and the second D temporary beam 4 are sequentially butted along the line direction, and the two ends of the first D temporary beam 3 and the second D temporary beam 4 are respectively erected on the three temporary piers 1. After the line is overhead, excavation is carried out below the middle of the first D temporary beam 3 and the second D temporary beam 4 to the design elevation for base reinforcement. The reinforcement method adopts the base high-pressure rotary jet pile 5 with an I-beam inserted therein. The base high-pressure rotary jet pile 5 is 0.7m in diameter and 10.62m in length. Five rows are arranged longitudinally with a spacing of 0.2m. The three inner rows of piles are constructed as interlocking piles. The base high-pressure rotary jet pile 5 at the bottom of the design position of the supporting wall 6 is inserted with an I20 I-beam. 50cm of the I-beam is reserved above the base high-pressure rotary jet pile 5 to be embedded in the bottom of the supporting wall 6 to increase the overall stability of the supporting wall 6.

[0027] 3) Construction of support wall 6: After the base reinforcement is completed, the support wall 6 is constructed above the base high-pressure jet grouting piles 5. The support wall 6 is made of reinforced concrete and a settlement observation point is set on the support wall 6. The reserved part of the base I-beam is embedded in the bottom of the support wall 6 to increase the stability of the support wall 6;

[0028] 4) Backfill: After the support wall 6 is completed and reaches the designed strength, backfill on both sides is carried out. Graded crushed stone is used for backfilling and filling is carried out in layers. The filling and compaction within 2 meters behind the support wall 6 is carried out by manual and small-scale mechanical compaction;

[0029] 5) Remove the first D-type temporary beam 3 and the second D-type temporary beam 4, and erect the third D-type temporary beam 7. The third D-type temporary beam 7 is set along the line direction, and the two ends of the third D-type temporary beam 7 are respectively erected on two supporting strong points 6. The overhead line is opened, the earthwork of the jacking section is excavated, and the jacking construction of the frame bridge 8 is carried out, that is, the frame bridge 8 is jacked under the third D-type temporary beam 7;

[0030] 6) Line settlement observation: Strictly implement the settlement observation system throughout the construction process to prevent the settlement of existing lines from endangering personal and driving safety.

[0031] (1) Settlement and displacement of D temporary beams: This is mainly done on the supporting walls of the temporary beams. Two observation points are set up on each supporting wall. After the temporary beams are erected, observations are made during excavation and foundation reinforcement. One observation point is set up at each D24 temporary beam support point on the supporting wall. Observations are made during the entire construction process.

[0032] (2) Track direction and gauge: In the speed-limited section, monitor the axis position and gauge: set up an observation point every 10m, monitor twice a day, and keep records for future reference.

[0033] (3) Problem handling:

[0034] Set the allowable deviation value: horizontal displacement of the supporting wall 2cm (cumulative) 5mm (per time)

[0035] Support wall settlement: 3cm (accumulative) 5mm (per time)

[0036] Line axis deviation: 5mm

[0037] Track spacing: +6mm, -2mm

[0038] During the construction process, the horizontal and vertical displacements of the D-type temporary beam and the existing roadbed were monitored in accordance with the quality target requirements. The monitoring data showed that neither the horizontal nor the vertical displacement exceeded the monitoring alarm values ​​required by the target.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A D-type temporary beam line reinforcement method under complex geological conditions, characterized in that: The specific steps are as follows: 1) Construction of temporary buttresses (1); 2) Construct the first D temporary beam (3) and the second D temporary beam (4) on the temporary pier (1) and reinforce the track at the same time. After the line is elevated, excavate below the middle of the first D temporary beam (3) and the second D temporary beam (4) to the design elevation for base reinforcement. The reinforcement method is to insert an I-beam into the base high-pressure rotary jet pile (5). The I-beam is reserved 50 cm above the base high-pressure rotary jet pile (5) to be embedded in the bottom of the supporting wall (6); 3) Construction of the supporting wall (6): After the base reinforcement is completed, the supporting wall (6) is constructed above the high-pressure jet grouting piles (5) of the base. The supporting wall (6) adopts a reinforced concrete structure, and a settlement observation point is set on the supporting wall (6). The reserved part of the base I-beam is embedded in the bottom of the supporting wall (6); 4) Backfilling: Backfilling is carried out after the supporting wall (6) is completed and reaches the designed strength; 5) Remove the first D-type temporary beam (3) and the second D-type temporary beam (4), and erect the third D-type temporary beam (7). The third D-type temporary beam (7) is set along the line direction, and the two ends of the third D-type temporary beam (7) are respectively erected on two supporting walls (6). The line is overhead, the earthwork of the jacking section is excavated, and the frame bridge (8) is jacked; 6) Line settlement observation: strictly implement the settlement observation system throughout the construction process to prevent the existing line settlement from endangering personal and driving safety; Three temporary piers (1) are distributed and constructed in the line reinforcement area along the line direction, the first D-type temporary beam (3) and the second D-type temporary beam (4) are connected in sequence along the line direction, and both ends of the first D-type temporary beam (3) and the second D-type temporary beam (4) are respectively erected on the three temporary piers (1).

2. The D-type temporary beam line reinforcement method under complex geological conditions according to claim 1 is characterized by: In the above 1), while the temporary buttresses (1) are being constructed, the jet grouting piles (2) are being constructed in parallel along the circumference of the line reinforcement area.

3. The D-type temporary beam line reinforcement method under complex geological conditions according to claim 1 is characterized by: The jet grouting piles (2) are double-row high-pressure, with a diameter of 0.7m, a length of 10.5m, a spacing of 0.5m, and an engagement of 0.2m. The inner jet grouting piles (2) are inserted into the Ⅰ20 I-steel and play a supporting role at the same time.

4. The D-type temporary beam line reinforcement method under complex geological conditions according to claim 1 is characterized by: In the above 3), the base high-pressure jet grouting piles (5) are φ0.7m and 10.62m long, and are arranged in 5 rows longitudinally with a spacing of 0.2m. The inner three rows of piles are constructed as interlocking piles. I20 I-beams are inserted into the base high-pressure jet grouting piles (5) at the bottom of the design position of the supporting wall (6).

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