Method for dismantling waste anchoring type dock wall in dry environment

Abstract

The invention discloses a method for dismantling a waste anchoring type dock wall in a dry environment. The method comprises the steps that S1, early-stage preparation is conducted; s2, the anchoring system is dismantled; s3, the dock wall structure is dismantled; s4, the steel sheet pile is pulled out; wherein the early-stage preparation stage comprises the step of arranging a displacement settlement observation point, a deep soil mass displacement meter and an underground water level observation well at the top of an excavation design slope so as to monitor the stress change condition of a soil mass. According to the method, by optimizing the dismantling process and accurately controlling the dismantling standard, the dismantling operation of the dock wall can be efficiently and safely completed, and the problems of soil instability and the like caused by dismantling can be effectively avoided.

Description

Technical Field

[0001] The invention relates to the technical field of ports and marine engineering, and in particular to a method for dismantling waste anchor-type dock walls in a dry environment. Background Art

[0002] With the advancement of global port modernization and the popularization of large deep-water ships, anchor-pull dock walls, as important dock structures, have been widely used in early projects due to their economy and efficiency. However, many obsolete anchor-pull dock walls have functional degradation and safety hazards due to lagging design standards, aging of anchoring systems, fatigue of wall structures, etc. Under the long-term influence of complex hydrological environments, these dock walls may experience anchor failure, wall deformation, or even collapse, which seriously affects the operational efficiency and safety of the dock.

[0003] The removal of abandoned anchor-type dock walls is technically complex and highly risky. Due to the special structural form of the anchor-type dock wall, its removal must take into account the stability of the soil, the control of groundwater, and the safety impact of the surrounding structures.

[0004] For this type of anchor-pull force system, the usual construction idea is to release the force of the anchor-pull structure, that is, to reduce the soil pressure behind the dock wall and then dismantle the anchor-pull dock wall as a whole. However, this approach has the following main problems:

[0005] (1) The tie rods need to be cut after most of the soil is removed in stages behind the wall. The tie rod spacing is usually set at 1.5m-1.8m. If the tie rod spacing is too small, it will limit the construction efficiency of soil reduction.

[0006] (2) After a large amount of soil is dropped, the tie rod is suspended too high, making it difficult to remove;

[0007] (3) The height of the dock wall is usually not less than 10m. After a large amount of rear soil is lowered, the cantilever of the dock wall is large, making it inconvenient to remove the lining concrete. If the steel sheet pile is old, it may break directly when the lining is removed.

[0008] Therefore, a method for dismantling old and abandoned anchor-type dock walls in a dry environment is provided. Summary of the invention

[0009] The purpose of the present invention is to overcome the existing defects and provide a method for dismantling old anchor-type dock walls in a dry environment. By optimizing the dismantling process and accurately controlling the dismantling standards, not only can the dock wall dismantling operation be completed efficiently and safely, but also the problems of soil instability caused by the dismantling can be effectively avoided.

[0010] The technical solution to achieve the above purpose is:

[0011] A method for dismantling a waste anchor-type dock wall in a dry environment, comprising:

[0012] Step S1, preliminary preparation;

[0013] Step S2, dismantling the anchor system;

[0014] Step S3, dismantling the dock wall structure;

[0015] Step S4, removing the steel sheet piles;

[0016] Among them, the preliminary preparation stage includes: setting up displacement and settlement observation points, deep soil displacement meters, and groundwater level observation wells at the top of the excavation design slope to monitor the changes in soil stress.

[0017] Preferably, in the step S1, the preliminary preparation stage further includes:

[0018] The hardened road surface on both sides of the dock wall needs to be removed, and open ditches and intercepting ditches need to be set up to control surface water flow;

[0019] In the dock wall area inside the dock, the passive earth pressure is increased by backfilling to stabilize the soil behind the dock wall.

[0020] At the anchor wall location of the dock wall, the soil is excavated to expose and determine the position of the tie rod.

[0021] Preferably, in step S2, the anchor system is removed, including:

[0022] Step S21, removing the riprap prism in front of the anchor wall to expose the connection portion between the tie rod and the anchor wall;

[0023] Step S22, setting a counter-pressure platform of a certain height and width inside the dock to increase the passive earth pressure on the dock wall;

[0024] Step S23, the long arm excavator digs part of the soil below the pull rod to the designed elevation, reduces the active soil pressure on the anchor system, and releases the tension on the anchor system;

[0025] Step S24, using a pickaxe to chisel away the lining concrete above the construction platform, and then cutting and removing the tie rods at the anchor wall and dock wall positions;

[0026] Step S25, further excavating the rear of the dock wall to completely expose the remaining anchor wall and riprap prism;

[0027] Step S26, removing the remaining anchor walls and riprap prisms, and cutting the steel sheet piles at the same time.

[0028] Preferably, in step S26, the steel sheet piles are cut in groups, with each group processing a maximum of 5 pieces, and are precisely cut by gas cutting equipment and then removed using mechanical equipment.

[0029] Preferably, in step S3, the dock wall structure is dismantled, including:

[0030] Step S31, using a top-down layered demolition method, using a pickaxe to chisel off the upper lining concrete on the working platform;

[0031] Step S32, the dock wall is then cut into sections, and then the secondary soil lowering is started and the working platform and the bottom structure are removed layer by layer;

[0032] Step S33, during the segmented cutting and soil lowering construction phase, displacement and settlement observation points, deep soil displacement meters, and groundwater level observation wells are set up to synchronously monitor the stress changes of the soil.

[0033] Preferably, in step S4, the steel sheet piles are removed by using a crawler crane + vibratory hammer.

[0034] The beneficial effects of the present invention are as follows: the present invention designs and builds a stable counter-pressure platform in front of the dock wall and partially lowers the soil behind the dock wall, thereby simply and reliably completing the force conversion of the anchor-pull system, providing great construction convenience for the soil lowering operation after the pull rods are removed, and providing a safe and efficient operation basis for the chiseling and segmented cutting of the dock wall lining concrete; during the demolition process, through the technology of dynamic soil monitoring management and gradual removal of anchor pull rods, the groundwater level and soil stress state are monitored in real time to ensure the soil stability at all stages of construction, avoid the risk of dock wall instability or soil slippage, and achieve safety, efficiency and controllability of construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a flow chart of a method for dismantling a waste anchor-type dock wall in a dry environment according to the present invention;

[0036] Figure 2 It is a specific flow chart of the removal of the anchoring system in the present invention;

[0037] Figure 3 It is a specific flow chart of the dismantling of the dock wall structure in the present invention;

[0038] Figure 4 It is a schematic diagram of the embodiment of the present invention in which the hardened road surface on both sides of the dock wall is removed and open ditches and intercepting ditches are set;

[0039] Figure 5 It is a schematic diagram of backfilling earth in the dock wall area inside the dock chamber according to an embodiment of the present invention;

[0040] Figure 6 is a schematic diagram of removing the riprap prism in front of the anchor wall to expose the connection portion between the tie rod and the anchor wall in an embodiment of the present invention;

[0041] Figure 7It is a schematic diagram of partially lowering the soil between the dock wall and the anchor wall and reserving the elevation at the connection position between the tie rod and the dock wall in an embodiment of the present invention;

[0042] Figure 8 It is a schematic diagram of using a pickaxe machine to chisel away the lining concrete above the construction platform, and then cutting and removing the tie rods at the anchor wall and dock wall positions in an embodiment of the present invention;

[0043] Fig. 9 It is a schematic diagram of further excavating the rear of the dock wall to +1.5m in an embodiment of the present invention to fully expose the remaining anchor wall and riprap prism;

[0044] Fig.10 is a schematic diagram of removing the remaining anchor wall and riprap prisms and cutting the steel sheet piles at the same time in an embodiment of the present invention;

[0045] Fig.11 Schematic diagram of the steel sheet pile cutting using group operation in an embodiment of the present invention;

[0046] Fig.12 It is a schematic diagram of simultaneously lowering soil in front of and behind the dock wall, and removing the dock wall lining and steel sheet piles layer by layer in an embodiment of the present invention. DETAILED DESCRIPTION

[0047] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0048] The present invention will be further described below in conjunction with the accompanying drawings.

[0049] like Figure 1 As shown, a method for dismantling a waste anchor-type dock wall in a dry environment comprises:

[0050] Step S1, preliminary preparation.

[0051] In the embodiment, the preliminary preparation stage includes: setting a displacement settlement observation point, a deep soil displacement meter, and a groundwater level observation well at the top of the excavation design slope to monitor the change of soil stress.

[0052] In the embodiment, the preliminary preparation stage also includes:

[0053] The hardened road surface on both sides of the dock wall needs to be removed, and open ditches and intercepting ditches need to be set up to control surface water flow;

[0054] In the dock wall area inside the dock, the passive earth pressure is increased by backfilling to stabilize the soil behind the dock wall.

[0055] At the anchor wall location of the dock wall, the soil is excavated to expose and determine the position of the tie rod.

[0056] Step S2, dismantling the anchor system.

[0057] like Figure 2 As shown, the anchor system is dismantled, including:

[0058] Step S21, removing the riprap prism in front of the anchor wall to expose the connection portion between the tie rod and the anchor wall.

[0059] Step S22: a counter-pressure platform of a certain height and width is provided inside the dock to increase the passive earth pressure on the dock wall.

[0060] Step S23, the long arm excavator digs part of the soil below the pull rod to the designed elevation, reduces the active soil pressure on the anchor system, and releases the tension on the anchor system.

[0061] Step S24, using a pickaxe to chisel away the lining concrete above the construction platform, and then cutting and removing the tie rods at the anchor wall and dock wall positions.

[0062] Step S25: further excavate the rear of the dock wall to completely expose the remaining anchor wall and riprap prism.

[0063] Step S26, removing the remaining anchor walls and riprap prisms, and cutting the steel sheet piles at the same time.

[0064] In the embodiment, the steel sheet piles are cut in groups, with each group processing a maximum of 5 pieces. After being precisely cut by gas cutting equipment, they are pulled out using mechanical equipment.

[0065] Step S3, dismantling the dock wall structure.

[0066] like Figure 3 As shown, the dock wall structure is dismantled, including:

[0067] Step S31, adopting the method of layered demolition from top to bottom, using a pickaxe machine to chisel off the upper lining concrete on the working platform.

[0068] Step S32, the dock wall is then cut into sections, and then secondary soil lowering is started to remove the working platform layer by layer until the bottom structure.

[0069] Step S33, during the segmented cutting and soil lowering construction phase, displacement and settlement observation points, deep soil displacement meters, and groundwater level observation wells are set up to synchronously monitor the stress changes of the soil.

[0070] Step S4, removing the steel sheet piles.

[0071] In the embodiment, the steel sheet piles are removed by using a crawler crane + vibratory hammer.

[0072] The method of the present invention is described in detail by the following examples:

[0073] 1. Preparation before construction:

[0074] like Figure 4 As shown in the figure, the hardened road surface about 0.4m thick behind the dock wall, the track beams above the tie rods and the corridor structure were removed, and open ditches and intercepting ditches were set up to effectively control the flow of surface water and ensure the environmental stability of the demolition operation; displacement and settlement observation points, deep soil displacement meters, groundwater level observation wells and other monitoring elements were set up on the top of the excavation design slope to monitor the changes in soil stress.

[0075] like Figure 5 As shown in the figure, in the dock wall area inside the dock, the soil is backfilled to -3.00mCD (area A) and -5.00mCD (area B), the top width is controlled to 5m, and the slope ratio is 1:2.5, to increase the passive earth pressure and stabilize the soil behind the dock wall. At the anchor wall position of the dock wall, the soil is excavated to +0.50mCD to expose and determine the position of the tie rod. The slope ratio and thickness are strictly controlled during the soil lowering operation to ensure that the soil pressure is released to the design standard, thereby achieving the dual guarantee of safe removal of the tie rod and overall stability of the dock wall.

[0076] 2. Dismantling of anchor system:

[0077] like Figure 6 As shown, the riprap prism in front of the anchor wall is removed to expose the connection between the tie rod and the anchor wall.

[0078] like Figure 7 As shown in the figure, the soil between the dock wall and the anchor wall is partially lowered to -1.50mCD to further reduce the active soil pressure on the dock wall. A working platform with an elevation of +0m is reserved at the connection position between the tie rod and the dock wall to facilitate workers to cut the tie rod.

[0079] like Figure 8 As shown, a pickaxe machine is used to first remove the lining concrete above the construction platform, and then the tie rods are cut and removed at the anchor wall and dock wall locations.

[0080] like Fig. 9 As shown, the rear of the dock wall was further excavated to +1.5m, completely exposing the remaining anchor wall and riprap prism.

[0081] like Fig.10 As shown, the remaining anchor wall and riprap prisms are removed and the steel sheet piles are cut at the same time.

[0082] like Fig.11 As shown, the steel sheet piles are cut in groups, with each group processing a maximum of 5 pieces. After being precisely cut by gas cutting equipment, they are pulled out using mechanical equipment. At the same time, non-essential personnel are restricted from entering the lifting area to ensure safety.

[0083] 3. Demolition of dock wall structure:

[0084] like Fig.12 As shown in the figure, the remaining dock wall demolition is carried out by combining phased construction, segmented cutting and synchronous monitoring. The soil is lowered simultaneously in front and behind the dock wall, and the soil height difference in front and behind the dock wall is controlled to be no more than 3.5m. Under this standard, the dock wall lining and steel sheet piles are removed layer by layer.

[0085] 4. Steel sheet pile removal:

[0086] After the lining concrete is completely removed, the steel sheet piles are removed using a crawler crane + vibratory hammer.

[0087] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments may still be modified, or some or all of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for dismantling old anchor-type dock walls in a dry environment, characterized in that: include: Step S1, preliminary preparation; Step S2, dismantling the anchor system; Step S3, dismantling the dock wall structure; Step S4, removing the steel sheet piles; Among them, the preliminary preparation stage includes: setting up displacement and settlement observation points, deep soil displacement meters, and groundwater level observation wells at the top of the excavation design slope to monitor the changes in soil stress.

2. The method for dismantling a waste anchor-type dock wall in a dry environment according to claim 1, characterized in that: In the step S1, the preliminary preparation stage also includes: The hardened road surface on both sides of the dock wall needs to be removed, and open ditches and intercepting ditches need to be set up to control surface water flow; In the dock wall area inside the dock, the passive earth pressure is increased by backfilling to stabilize the soil behind the dock wall. At the anchor wall location of the dock wall, the soil is excavated to expose and determine the position of the tie rod.

3. The method for dismantling old anchor-type dock walls in a dry environment according to claim 1, characterized in that: In the step S2, the anchor system is removed, including: Step S21, removing the riprap prism in front of the anchor wall to expose the connection portion between the tie rod and the anchor wall; Step S22, setting a counter-pressure platform of a certain height and width inside the dock to increase the passive earth pressure on the dock wall; Step S23, the long arm excavator digs part of the soil below the pull rod to the designed elevation, reduces the active soil pressure on the anchor system, and releases the tension on the anchor system; Step S24, using a pickaxe to chisel away the lining concrete above the construction platform, and then cutting and removing the tie rods at the anchor wall and dock wall positions; Step S25, further excavating the rear of the dock wall to completely expose the remaining anchor wall and riprap prism; Step S26, removing the remaining anchor walls and riprap prisms, and cutting the steel sheet piles at the same time.

4. The method for dismantling a waste anchor-type dock wall in a dry environment according to claim 3, characterized in that: In step S26, the steel sheet piles are cut in groups, with each group processing a maximum of 5 pieces. After being precisely cut by gas cutting equipment, they are removed using mechanical equipment.

5. The method for dismantling old anchor-type dock walls in a dry environment according to claim 1, characterized in that: In step S3, the dock wall structure is dismantled, including: Step S31, using a top-down layered demolition method, using a pickaxe to chisel off the upper lining concrete on the working platform; Step S32, the dock wall is then cut into sections, and then the secondary soil lowering is started and the working platform and the bottom structure are removed layer by layer; Step S33, during the segmented cutting and soil lowering construction phase, displacement and settlement observation points, deep soil displacement meters, and groundwater level observation wells are set up to synchronously monitor the stress changes of the soil.

6. The method for dismantling old anchor-type dock walls in a dry environment according to claim 1, characterized in that: In step S4, the steel sheet piles are removed by using a crawler crane + vibratory hammer.

Images