In-situ protection system and method for ancient and famous trees in construction period of excavation engineering area

Abstract

The invention relates to the technical field of tree protection, and discloses an in-situ protection system and method for ancient and famous trees in the construction period of an excavation engineering district, the in-situ protection system comprises the ancient and famous trees located in the land, a protection wall is arranged on the surface of the land and located on the periphery of the ancient and famous trees, and an iron square grid is arranged at the top of the protection wall; outer side drainage ditches are arranged on the surface of the land and located on the periphery of the protection enclosing wall, a water supplementing and draining system is arranged on one side of the protection enclosing wall, foundation pit fender posts extending downwards are arranged on the surface of the land and located on the periphery of the outer side drainage ditches and the periphery of the water supplementing and draining system, and Larsen steel sheet piles are arranged on the inner sides of the foundation pit fender posts. An underground anti-seepage and anti-seismic soft wall, an inner side drainage ditch and a water level observation well are sequentially arranged on the surface of the land and located in the protection enclosing wall. According to the in-situ protection system and method for the ancient and famous trees in the excavation engineering area during the construction period, the retention utilization rate and the survival rate of original trees in the construction area can be increased, and the ecological environment in the construction area is improved.

Description

Technical Field

[0001] The invention relates to the technical field of tree protection, and in particular to an on-site protection system and method for ancient and famous trees during the construction period of an excavation engineering area. Background Art

[0002] Ancient and famous trees are not only naturally grown trees, but also "living cultural relics" that carry the long historical traditions, cultural connotations and symbolic significance together with cultural relics buildings, grottoes, stone carvings, and ruins. They have important ecological, historical, cultural and scientific value. A series of relevant policies have indeed been introduced to attach importance to and strengthen the protection of ancient and famous trees.

[0003] With the rapid development of urban construction and supporting engineering construction, the issue of how to effectively protect ancient trees and famous trees in urban construction areas has become increasingly prominent. At present, the main methods of tree protection in urban construction areas are transplant protection or on-site protection. The on-site protection scheme has the advantages of reducing project costs, high tree survival rate, and no damage to the ecological environment. Therefore, the on-site protection scheme has become the best choice for protecting ancient trees and famous trees. In addition, urban construction projects usually reduce the elevation of the original ground, and the excavation construction area formed by the reduction of the ground elevation usually has a great impact on the growth quality of the original trees in the construction area, such as lowering the groundwater level, changing the soil density, cutting the roots, etc., affecting the survival rate of the trees. Even if the trees can survive in the excavation area, the overall growth of the trees in the future will be greatly affected. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the shortcomings of the prior art, the present invention provides a system and method for on-site protection of ancient and famous trees in the construction period of an excavation project area, which can improve the retention utilization rate and survival rate of the original trees in the construction area, improve the ecological environment in the construction area, and solve the problems raised by the background technology.

[0006] (II) Technical solution

[0007] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an on-site protection system for ancient trees and famous trees during the construction period of an excavation engineering area, comprising ancient trees and famous trees located inside the land, a protective wall is arranged on the surface of the land and outside the ancient trees and famous trees, an iron grid is arranged on the top of the protective wall, an outer drainage ditch is arranged on the surface of the land and outside the protective wall, and a supplementary drainage system is arranged on one side of the protective wall, downwardly extending foundation pit retaining piles are arranged on the surface of the land and outside the outer drainage ditch and the supplementary drainage system, and Larsen steel sheet piles are arranged on the inner side of the foundation pit retaining piles, an underground anti-seepage and earthquake-proof soft wall, an inner drainage ditch and a water level observation well are arranged in sequence on the surface of the land and inside the protective wall, a protective grid covering the ancient trees and famous trees is arranged on the surface of the land, and a spray moisturizing system is fixedly installed on the inner wall of the protective grid.

[0008] Preferably, the wall of the protective fence is treated to prevent water seepage, the top of the iron grid is provided with barbed wire, the protective fence is arranged at a position 1 meter outside the vertical projection of the crown of the ancient tree, and an entrance door is arranged on one side of the protective fence.

[0009] Preferably, the foundation pit retaining piles are arranged at a position of 20 m from the protective wall, and the length of the Larsen steel sheet piles is 15 m.

[0010] Preferably, the underground anti-seepage and shock-proof soft wall is set in an annular ditch on the ground, and decomposition-resistant non-woven fabrics are provided on both sides of the annular ditch, and the inside of the annular ditch and between the two decomposition-resistant non-woven fabrics are filled with a perlite layer, and a seepage pipe is laid at the bottom of the annular ditch and below the perlite layer.

[0011] Preferably, two deep water level observation wells are built outside the projection surface range of the ancient trees and famous trees more than 2m, and two shallow water level observation wells are built within the projection surface range of the ancient trees and famous trees 2m, the deep water level observation wells are 1.8m deep, and the diameter of the PVC pipe is 30cm.

[0012] Preferably, the cross-section of the inner drainage ditch is trapezoidal, with a width of 80 cm at the top, 30 cm at the bottom, and a depth of 1.3 m. The inner side is lined with permeable bricks, and the bottom and outer side are sealed with cement.

[0013] Preferably, the drainage system is a water collection well with a length of 6m, a width of 2m and a depth of 4m, and is coated with cement. Two fully automatic high-power drainage pumps and drainage gates are installed inside the water collection well.

[0014] Preferably, the top of the protection grid is 2.5m higher than the top of the ancient and famous tree, and the side is 2m larger than the crown of the ancient and famous tree, and the dust blanket is removable around the surrounding parts of the protection grid.

[0015] A method for on-site protection of ancient and famous trees in a construction period of an excavation project area comprises the following steps:

[0016] Step 1: Temporarily build a protective fence, remove wild and vicious weeds and other debris. The protection range of ancient and famous trees should not be less than 5 meters outside the vertical projection of the tree crown. Therefore, during construction, a temporary fully enclosed protective fence is built outside the determined protection range, that is, 5 meters outside the vertical projection of the tree crown, and an entry and exit door is installed. It is usually locked. The height of the protective fence is 2m, and the wall of the protective fence is treated for water seepage. The upper part of the protective fence is a 1.5m high iron grid, and the top of the iron grid is equipped with barbed wire;

[0017] Step 2: Set up foundation pit retaining piles and Larsen steel sheet piles. Because the excavation project is constructed around ancient trees and sometimes the depth is more than 10 meters, in order to effectively avoid soil collapse, about 20m of foundation pit retaining piles are set around the protective wall. At the same time, about 15m of Larsen steel sheet piles are set inside the foundation pit retaining piles to prevent groundwater leakage, alkaline water inflow caused by cement application on the outside, resulting in a large change in the soil pH value of the ancient tree protection area, and changes in soil pressure within the protection range caused by basement excavation;

[0018] Step 3: Set up underground anti-seepage and anti-vibration soft walls. In order to effectively prevent the soil in the protection range of ancient trees and famous trees from vibrating violently due to the construction of large-scale mechanical equipment outside, which in turn damages the root system, a ring ditch with a depth of 3m and a width of 80cm is dug along the inner side of the wall. Decomposable non-woven fabrics are laid on both sides of the ditch, and a perlite layer is filled in the middle to isolate the soil on both sides for the purpose of buffering and shock absorption. At the same time, a seepage pipe is laid on the bottom layer and anti-blocking treatment is performed. When alkaline water from the outside flows in, it can flow out through the seepage pipe to avoid soil pollution within the protection range. In addition, a valve is set at the drainage outlet of the seepage pipe to control the water flow rate, so as to achieve the purpose of initially controlling the groundwater level within the protection range.

[0019] Step 4: Dig inner drainage ditches and water level observation wells. To effectively monitor the changes in groundwater level and pH value, two deep water level observation wells are built outside the projection surface of ancient trees and famous trees in the four directions of east, west, south and north, and more than 2m outside. Two shallow water observation wells are built within the projection surface of ancient trees and famous trees to observe the changes in water level during construction. A standard depth observation well is built outside the construction scope to serve as a water level reference during construction and maintenance. The depth of the deep water level observation well is 1.8m deep, the diameter of the PVC pipe is 30cm, there are multiple water-permeable holes on the pipe wall, a well cover is set on the upper side, and the outer and lower gaps of the pipe are filled with ceramsite, coarse sand and pebbles. Floats and rulers are set inside the pipe to facilitate reading the water level depth. At the same time, arrange relevant personnel to regularly observe and record water level values. The water level observation well must be observed every day and compared with the water level of the standard well to prevent accidents.

[0020] Step 5: Set up a drainage system. Dig a 6m long, 2m wide, and 4m deep water collection well on the south side of the wall and apply cement to prevent groundwater from seeping in. Install two fully automatic high-power drainage pumps and drainage gates in the well. When the water level reaches a certain preset height, the drainage pump automatically starts to force the water to the predetermined area. Because deep underground excavation will cause a large amount of soil moisture loss within the protection range of ancient trees and famous trees, and the groundwater level will drop seriously, a 6.66cm diameter water pipe is introduced from the outside. When the water level is abnormal, open the valve in time to replenish water to ensure the normal water level within the protection range to avoid the root system from not absorbing enough water and causing leaf wilting and growth decline;

[0021] Step 6: Build a protective grid. Build a protective grid outside the ancient and famous trees. The top of the protective grid is 2.5m higher than the top of the ancient and famous trees, and the side is 2m larger than the crown of the ancient and famous trees. The dust blanket is removed around the protective grid to prevent cement dust from damaging the leaves and tree bodies;

[0022] Step 7: Install the spray moisturizing system. Install the spray system on the upper side of the protective grid and spray automatically and regularly. The top spray system should be 2.5m away from the ancient trees and the side spray system should be 2m away from the ancient trees.

[0023] (III) Beneficial effects

[0024] Compared with the prior art, the present invention provides a system and method for protecting ancient and famous trees in situ during the construction period of an excavation project area, which has the following beneficial effects:

[0025] 1. Improve the retention and utilization rate and survival rate of trees: By building a comprehensive protection system, such as setting up protection walls, foundation pit retaining piles, Larsen steel sheet piles and other facilities, we can effectively resist construction interference, reduce tree damage factors caused by construction, and significantly improve the retention and utilization rate and survival rate of the original trees in the construction area.

[0026] 2. Stabilize the soil environment: The setting of underground anti-seepage and anti-vibration soft walls plays a key role. The combination of perlite layer and decomposition-resistant non-woven fabric can buffer vibrations and prevent the roots from being damaged by construction vibrations. The seepage pipes can regulate the groundwater level, prevent the intrusion of alkaline water, maintain appropriate humidity and pH of the soil, and ensure a healthy growth environment for tree roots.

[0027] 3. Accurate water level control: The multi-directional layout of water level observation wells, combined with an efficient drainage system, enables real-time and accurate monitoring of groundwater levels. When the water level is too high, the strong drainage pump automatically operates, and when the water level is too low, external water is introduced in time to ensure that the water supply to the tree roots is stable throughout the construction process, avoiding poor growth caused by water level fluctuations.

[0028] 4. Prevent physical damage and moisturize: The protective grid and spray moisturizing system complement each other. The grid provides a protective umbrella for the trees to protect them from damage such as construction dust and impact from foreign objects. The spray system automatically sprays according to settings to maintain appropriate air humidity, compensate for the impact of humidity fluctuations in the construction area on the trees, help keep the branches and leaves of the trees moisturized, and enhance photosynthesis and physiological activity. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a structural schematic diagram of an on-site protection system for ancient and famous trees in an excavation engineering area during the construction period proposed by the present invention;

[0030] Figure 2 for Figure 1 A top view of the protective wall and iron grid;

[0031] Figure 3 for Figure 1 Structural schematic diagram of underground anti-seepage and earthquake-proof soft wall;

[0032] Figure 4 for Figure 1 Schematic diagram of the structure of the central drainage system.

[0033] In the figure: 1. Land; 2. Ancient and famous trees; 3. Protective fence; 4. Iron grid; 5. Outer drainage ditch; 6. Supplementary drainage system; 7. Foundation pit retaining piles; 8. Larsen steel sheet piles; 9. Underground anti-seepage and earthquake-proof soft wall; 10. Inner drainage ditch; 11. Water level observation well; 12. Protective grid; 13. Installation of spray moisturizing system; 14. Annular ditch; 15. Decomposition-resistant non-woven fabric; 16. Perlite layer; 17. Seepage pipe; 18. Collection well; 19. Strong drainage pump; 20. Drainage gate. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] See also Figure 1-4, an on-site protection system for ancient trees and famous trees during the construction period of an excavation project area, comprising ancient trees and famous trees 2 located inside a land 1, a protective fence 3 is arranged on the surface of the land 1 and outside the ancient trees and famous trees 2, the wall of the protective fence 3 is treated with water seepage prevention, the protective fence 3 is arranged 5 meters outside the vertical projection of the crown of the ancient trees and famous trees 2, and an inlet and outlet door is arranged on one side of the protective fence 3; an iron grid 4 is arranged on the top of the protective fence 3, and a barbed wire is arranged on the top of the iron grid 4, and the barbed wire can prevent people from climbing over; an outer drainage ditch 5 is arranged on the surface of the land 1 and outside the protective fence 3, and a supplementary drainage system 6 is arranged on one side of the protective fence 3, the surface of the land 1 and the outer drainage ditch 5 and the supplementary drainage system 6 are arranged The periphery of the drainage system 6 is provided with downwardly extending foundation pit retaining piles 7, and the inner side of the foundation pit retaining piles 7 is provided with Larsen steel sheet piles 8. The foundation pit retaining piles 7 are arranged at a position of 20m from the protective wall 3, and the length of the Larsen steel sheet piles 8 is 15m; the surface of the land 1 and the inside of the protective wall 3 are successively provided with underground anti-seepage and earthquake-proof soft walls 9, inner drainage ditches 10 and water level observation wells 11; the surface of the land 1 is provided with a protective grid 12 covering the ancient trees and famous trees 2; the top of the protective grid 12 is 2.5m higher than the top of the ancient trees and famous trees 2, and the side is 2m larger than the crown of the ancient trees and famous trees 2; the dust-proof blankets are disassembled around the surrounding parts of the protective grid 12, and the inner wall of the protective grid 12 is fixedly installed with a spray moisturizing system 13.

[0036] An underground anti-seepage and anti-seismic soft wall 9 is set in an annular ditch 14 on the land 1, and decomposition-resistant non-woven fabrics 15 are set on both sides of the annular ditch 14, and the inside of the annular ditch 14 and between the two decomposition-resistant non-woven fabrics 15 are filled with a perlite layer 16, and a seepage pipe 17 is laid at the bottom of the annular ditch 14 and below the perlite layer 16; two deep water level observation wells are built outside the projection surface range of more than 2m of the ancient trees and famous trees 2, and two shallow water level observation wells are built within the projection surface range of 2m of the ancient trees and famous trees 2, the deep water level observation well is 1.8m deep, and the diameter of the PVC pipe is 30cm; the cross-section of the inner drainage ditch 10 is trapezoidal, with an upper width of 80cm, a lower width of 30cm, a depth of 1.3m, and seepage bricks are laid on the inside, and the bottom and the outside are sealed with cement.

[0037] The drainage system 6 is a water collection well 18 with a length of 6m, a width of 2m and a depth of 4m, and is coated with cement. Two fully automatic high-power drainage pumps 19 and a drainage gate 20 are installed inside the water collection well 18. The drainage gate 20 can be lifted up or lowered by a lifting device.

[0038] A method for on-site protection of ancient and famous trees in a construction period of an excavation project area comprises the following steps:

[0039] Step 1: temporarily build a protective fence 3, remove wild malignant weeds and other debris. The protection range of the ancient trees and famous trees 2 should not be less than 5 meters outside the vertical projection of the tree crown. Therefore, during construction, a temporary fully enclosed protective fence 3 is built outside the determined protection range, that is, 5 meters outside the vertical projection of the tree crown, and an inlet and outlet door is installed. It is usually locked. The wall height of the protective fence 3 is 2m, and the wall of the protective fence 3 is treated with water seepage prevention. The upper part of the protective fence 3 is a 1.5m high iron grid 4, and the top of the iron grid 4 is provided with barbed wire;

[0040] Step 2: Setting up foundation pit retaining piles 7 and Larsen steel sheet piles 8. Because the excavation project is constructed around the ancient trees and famous trees 2, sometimes the depth is more than 10 meters. In order to effectively avoid soil collapse, foundation pit retaining piles 7 of about 20 meters are set around the protective wall 3. At the same time, Larsen steel sheet piles 8 of about 15 meters in length are set inside the foundation pit retaining piles 7 to prevent groundwater leakage, alkaline water inflow caused by cement application on the outside, resulting in a large change in the soil pH value of the ancient trees and famous trees 2 protection area, and changes in soil pressure within the protection range caused by basement excavation;

[0041] Step 3: Set up an underground anti-seepage and anti-vibration soft wall 9. In order to effectively prevent the soil in the protection range of the ancient trees and famous trees 2 from vibrating violently due to the construction of large-scale mechanical equipment on the outside, thereby damaging the root system, a ring ditch 15 with a depth of 3m and a width of 80cm is dug along the inner side of the wall. Decomposition-resistant non-woven fabrics 16 are laid on both sides of the ditch, and a perlite layer 17 is filled in the middle to isolate the soil on both sides for the purpose of buffering and shock absorption. At the same time, a seepage pipe 18 is laid on the bottom layer and anti-blocking treatment is performed. When alkaline water from the outside flows in, it can flow out through the seepage pipe 18 to avoid soil pollution within the protection range. In addition, a valve is set at the drain outlet of the seepage pipe 18 to control the water flow rate, so as to achieve the purpose of initially controlling the groundwater level within the protection range.

[0042] Step 4: Dig inner drainage ditch 10 and water level observation well 11. To effectively monitor the changes of groundwater level and pH value, two deep water level observation wells are built outside the projection surface range of ancient trees and famous trees 2 in the four directions of east, west, south and north, and more than 2m outside. Two shallow water observation wells are built within the projection surface range of ancient trees and famous trees 2 to observe the changes of water level during construction. A standard depth observation well is built outside the construction range to serve as a water level reference during construction and maintenance. The depth of the deep water level observation well is 1.8m deep, the diameter of the PVC pipe is 30cm, there are multiple water-permeable holes on the pipe wall, a well cover is set on the upper side, and the outer and lower gaps of the pipe are filled with ceramsite, coarse sand and pebbles. Floats and rulers are set inside the pipe to facilitate reading the water level depth. At the same time, corresponding personnel are arranged to regularly observe and record the water level value. The water level observation well 11 must be observed every day and compared with the water level of the standard well to prevent accidents.

[0043] Step 5: Set up a drainage system 6. Dig a 6m long, 2m wide, and 4m deep water collection well 18 on the south side of the wall, and apply cement to prevent groundwater from seeping in. Install two fully automatic high-power drainage pumps 19 and drainage gates 20 in the well. When the water level reaches a certain preset height, the drainage pump 19 automatically starts to force the water to the predetermined area. Because deep underground excavation will cause a large amount of soil moisture to be lost within the protection range of the ancient trees and famous trees 2, and the groundwater level will drop seriously, a tap water pipe with a diameter of 6.66cm is introduced from the outside. When the water level is abnormal, open the valve in time to replenish water to ensure that the water level within the protection range is normal, so as to avoid the situation where the roots cannot absorb enough water and the leaves wilt and the growth decline;

[0044] Step 6: Build a protective grid 12. Build a protective grid 12 outside the ancient and famous trees 2. The top of the protective grid 12 is 2.5m higher than the top of the ancient and famous trees 2, and the side is 2m larger than the crown of the ancient and famous trees 2. The dust blanket is removed from the surrounding parts of the protective grid 12 to prevent cement dust from damaging the leaves and tree bodies;

[0045] Step seven: Install the spray moisturizing system 13. Install the spray system 13 on the upper side of the protective grid 12 to automatically spray regularly. The top spray system 13 is 2.5m away from the ancient tree 2, and the side spray system 13 is 2m away from the ancient tree 2. The spray angle is precisely adjustable to create a moist and fresh microclimate environment for the trees in all directions, alleviating the negative impact of construction dust and dry air on tree growth.

[0046] It should be noted that the term "comprises" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, article, or device that includes a series of elements includes not only those elements, but also includes other elements that are not explicitly listed, or also includes elements inherent to such process, method, article, or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article, or device that includes the element.

[0047] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A system for protecting ancient and famous trees in situ during the construction period of an excavation project area, comprising ancient and famous trees (2) located inside the land (1), characterized in that: A protective wall (3) is arranged on the surface of the land (1) and outside the ancient and famous trees (2), and an iron grid (4) is arranged on the top of the protective wall (3). An outer drainage ditch (5) is arranged on the surface of the land (1) and outside the protective wall (3), and a drainage system (6) is arranged on one side of the protective wall (3). Foundation pit retaining piles (7) extending downward are arranged on the surface of the land (1) and outside the outer drainage ditch (5) and the drainage system (6), and Larsen steel sheet piles (8) are arranged on the inner side of the foundation pit retaining piles (7). An underground anti-seepage and earthquake-proof soft wall (9), an inner drainage ditch (10) and a water level observation well (11) are arranged in sequence on the surface of the land (1) and inside the protective wall (3). A protective grid frame (12) covering the ancient and famous trees (2) is arranged on the surface of the land (1), and a spray moisturizing system (13) is fixedly installed on the inner wall of the protective grid frame (12).

2. The on-site protection system for ancient and famous trees in the construction period of the excavation project area according to claim 1 is characterized by: The wall of the protective fence (3) is treated to prevent water seepage, the top of the iron grid (4) is provided with barbed wire, the protective fence (3) is arranged at a position 5 meters outside the vertical projection of the crown of the ancient tree (2), and an entrance door is arranged on one side of the protective fence (3).

3. The on-site protection system for ancient and famous trees in the construction period of the excavation project area according to claim 1 is characterized by: The foundation pit retaining piles (7) are arranged at a position of 20 m from the protective wall (3), and the length of the Larsen steel sheet piles (8) is 15 m.

4. The on-site protection system for ancient and famous trees in the construction period of the excavation project area according to claim 1 is characterized by: The underground anti-seepage and anti-vibration soft wall (9) is arranged in an annular ditch (14) on the land (1), and decomposition-resistant non-woven fabrics (15) are arranged on both sides of the annular ditch (14), and a perlite layer (16) is filled inside the annular ditch (14) and between two decomposition-resistant non-woven fabrics (15), and a water seepage pipe (17) is laid at the bottom of the annular ditch (14) and below the perlite layer (16).

5. The on-site protection system for ancient and famous trees in the construction period of the excavation project area according to claim 1 is characterized by: Two deep water level observation wells are built outside the projection surface range of the ancient tree (2) at a distance of 2 m, and two shallow water level observation wells are built within the projection surface range of the ancient tree (2) at a distance of 2 m. The deep water level observation wells are 1.8 m deep and the diameter of the PVC pipes is 30 cm.

6. The on-site protection system for ancient and famous trees in the construction period of the excavation project area according to claim 1 is characterized by: The cross section of the inner drainage ditch (10) is trapezoidal, with a width of 80 cm at the top, a width of 30 cm at the bottom, and a depth of 1.3 m. The inner side is lined with permeable bricks, and the bottom and outer side are sealed with cement.

7. The on-site protection system for ancient and famous trees in the construction period of the excavation project area according to claim 1 is characterized by: The drainage system (6) is a water collection well (18) with a length of 6 m, a width of 2 m, and a depth of 4 m, and is coated with cement. Two fully automatic high-power drainage pumps (19) and a drainage gate (20) are installed inside the water collection well (18).

8. The on-site protection system for ancient and famous trees in the construction period of the excavation project area according to claim 1 is characterized by: The top of the protective grid (12) is 2.5 m higher than the top of the ancient and famous tree (2), and the side is 2 m larger than the crown of the ancient and famous tree (2). The surrounding parts of the protective grid (12) are equipped with a removable dust blanket.

9. A method for on-site protection of ancient and famous trees in an excavation engineering area during the construction period, which uses the on-site protection system for ancient and famous trees in an excavation engineering area during the construction period as described in claims 1-8, characterized in that: The following steps are involved: Step 1: temporarily build a protective fence (3) to remove wild and malignant weeds and other debris. The protection range of the ancient and famous trees (2) should not be less than 5 meters outside the vertical projection of the tree crown. Therefore, during construction, a temporary fully enclosed protective fence (3) is built outside the determined protection range, that is, 5 meters outside the vertical projection of the tree crown, and an entry and exit door is installed. It is usually locked. The wall height of the protective fence (3) is 2m, and the wall of the protective fence (3) is treated with water seepage prevention. The upper part of the protective fence (3) is a 1.5m high iron grid (4), and the top of the iron grid (4) is provided with barbed wire; Step 2: Setting up foundation pit retaining piles (7) and Larsen steel sheet piles (8). Because the excavation project is constructed around the ancient trees (2), the depth is sometimes more than 10 meters. In order to effectively prevent soil collapse, foundation pit retaining piles (7) of about 20 meters are set around the protective wall (3). At the same time, Larsen steel sheet piles (8) of about 15 meters in length are set inside the foundation pit retaining piles (7) to prevent groundwater leakage, alkaline water inflow caused by cement application on the outside, resulting in a large change in the soil pH value of the ancient trees (2) protection area, and changes in soil pressure within the protection range caused by basement excavation; Step 3: Setting up an underground anti-seepage and anti-vibration soft wall (9). In order to effectively prevent the soil in the protection range of the ancient trees (2) from vigorous vibration caused by the construction of large-scale mechanical equipment outside, thereby damaging the root system, a ring-shaped ditch (15) with a depth of 3m and a width of 80cm is dug along the inner side of the wall. Decomposable non-woven fabrics (16) are laid on both sides of the ditch, and a perlite layer (17) is filled in the middle to isolate the soil on both sides for the purpose of buffering and shock absorption. At the same time, a seepage pipe (18) is laid on the bottom layer and anti-blocking treatment is performed. When alkaline water from the outside flows in, it can flow out through the seepage pipe (18) to avoid soil pollution in the protection range. In addition, a valve is set at the drainage outlet of the seepage pipe (18) to control the water flow rate, so as to achieve the purpose of initially controlling the groundwater level in the protection range. Step 4: dig an inner drainage ditch (10) and a water level observation well (11). To effectively monitor the changes in groundwater level and pH value, two deep water level observation wells are built outside the projection surface of the ancient trees (2) at a distance of 2 m in the four directions of east, west, south and north. Two shallow water observation wells are built within the projection surface of the ancient trees (2) to observe the changes in water level during construction. A standard depth observation well is built outside the construction area to serve as a water level reference during construction and maintenance. The depth of the deep water level observation well is 1.8 m deep. The diameter of the PVC pipe is 30 cm. There are multiple water permeable holes on the pipe wall. A well cover is set on the upper side. The outer and lower gaps of the pipe are filled with ceramsite, coarse sand and pebbles. A float and a ruler are set inside the pipe to facilitate reading the water level depth. At the same time, corresponding personnel are arranged to regularly observe and record the water level value. The water level observation well (11) must be observed every day and compared with the water level of the standard well to prevent accidents. Step 5: Set up a drainage system (6). Dig a 6m long, 2m wide and 4m deep water collection well (18) on the south side of the wall and apply cement to prevent groundwater from seeping in. Install two fully automatic high-power drainage pumps (19) and drainage gates (20) in the well. When the water level reaches a certain preset height, the drainage pump (19) automatically starts to force the water to the predetermined area. Because deep underground excavation will cause a large amount of soil moisture to be lost within the protection range of the ancient trees (2), and the groundwater level will drop seriously, a 6.66cm diameter water pipe is introduced from the outside. When the water level is abnormal, open the valve in time to replenish water to ensure that the water level within the protection range is normal, so as to avoid the situation where the roots cannot absorb enough water and the leaves wilt and the growth declines; Step 6: Build a protective grid (12). Build a protective grid (12) outside the ancient and famous tree (2). The top of the protective grid (12) is 2.5 meters higher than the top of the ancient and famous tree (2), and the side is 2 meters larger than the crown of the ancient and famous tree (2). The dust blanket is removed from the surrounding parts of the protective grid (12) to prevent cement dust from damaging the leaves and tree body; Step 7: Install the spray moisturizing system (13). Install the spray system (13) on the upper side of the protective grid (12) to automatically spray regularly. The top spray system (13) is 2.5m away from the ancient tree (2), and the side spray system (13) is 2m away from the ancient tree (2).

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