Device and method for vibrating and compacting saline soil foundation

Abstract

The present invention provides a device and method for vibrating and compacting a saline soil foundation, comprising a traveling device and a vibrating unit; the traveling device comprises a vehicle and a guide frame integrated on the vehicle, a high-pressure water pump, a water pump, a hot water boiler, a thermal oil boiler and a control host; the vibrating unit comprises a vibrating hammer, a vibrating rod and a vibrating plate suspended from the guide frame, and the vibrating rod and the vibrating plate are switchably mounted on the lower end action surface of the vibrating hammer; the vibrating rod is used for vibrating and compacting the soil once, and during the process, a high-temperature water jet is sprayed into the soil to dissolve the soluble salt and then pump it away; the vibrating plate is used for vibrating and compacting twice, and the surface of the soil is vibrated and compacted, and the control host is used to control the vibration frequency of the vibrating hammer, as well as the working states of the high-pressure water pump, the water pump, the hot water boiler and the thermal oil boiler. The device and method for vibrating and compacting a saline soil foundation have the advantages of simpler process, higher construction convenience, good reinforcement effect and excellent economic effect.

Description

Technical Field

[0001] The invention relates to the technical field of saline soil foundation treatment, and in particular to a device and method for vibrating and compacting a saline soil foundation. Background Art

[0002] Saline soil is widely distributed in Northwest my country, and infrastructure construction tasks are difficult to carry out. The reason is that the nature of saline soil foundation is complex, and there are diseases such as solubility, salt swelling, and corrosion. Solubility refers to the dissolution and loss of soluble salts in saline soil after being soaked in water, which causes the soil structure to loosen and the soil to sink. Salt swelling refers to the change in the state of soluble salts in saline soil after changes in temperature or water content, resulting in an increase in soil volume. Corrosion refers to the chemical reaction between soluble salts in saline soil and reinforced concrete to produce corrosion. The presence of soluble salts in the soil is the root cause of saline soil engineering problems. When used as a natural foundation, it must be reinforced accordingly.

[0003] Specifically, removing soluble salts from the soil and then compacting it to increase the dry density of the soil is an effective reinforcement method. Commonly used saline soil foundation treatment methods include water pre-dissolution, dynamic compaction, water pre-dissolution + dynamic compaction, replacement and chemical treatment, etc. These methods have their own scope of application and advantages, as well as certain limitations. For example, the water pre-dissolution + dynamic compaction method takes a long time to soak, which is not conducive to shortening the construction period, and the large vibration and noise generated during the construction process have a great impact on the lives of surrounding residents; the replacement method is only suitable for shallow foundation treatment, and the upper load of the building is small, and it is laborious and time-consuming; the chemical treatment method has a relatively high treatment cost and pollutes the environment.

[0004] For example, the Chinese invention patent "Combined drainage system and dynamic compaction treatment method for saline soil areas" (publication number: CN101349051B) discloses a combined drainage system and dynamic compaction treatment method for saline soil areas, which solves the technical problem that the bearing capacity of the foundation is not significantly improved after the usual foundation treatment, but the cost is high and the construction period is long. The technical solution adopted by the invention to solve its technical problem is: this combined drainage system for saline soil areas is characterized by: a plastic drainage belt arranged longitudinally in the foundation soil and a sand and gravel drainage cushion layer on the surface of the foundation soil are combined into a longitudinal and transverse drainage channel, and the upper end of the drainage channel in the local area merges into a tamping pit, and a drainage pump is arranged in the tamping pit, and the drainage pump is connected to the drainage pipe. This combined drainage and dynamic compaction foundation treatment method for saline soil areas arranges plastic drainage belts in the treatment area according to the design requirements, and the construction steps are: 1) construct plastic drainage belts in the treatment area. 2) Lay a sand and gravel drainage cushion layer at the position where each drainage belt is covered on the surface of the treatment area, and the plastic drainage belt and the sand and gravel drainage cushion layer are combined to form a channel for dredging and discharging groundwater. 3) Place points on the gravel drainage cushion layer and use a rammer to perform strong tamping. 4) Form a tamping pit at each strong tamping location. 5) Wait for the groundwater in the foundation to flow into each plastic drainage belt, flow to the gravel drainage cushion layer through the plastic drainage belt, and gather into the tamping pit through the gravel drainage cushion layer, and pump the groundwater gathered in the tamping pit out of the construction site. 6) Backfill the tamping pit and level it. Although this method can form a drainage channel in the foundation soil, greatly improve the bearing capacity and modulus of the foundation, meet the requirements of various building construction in the salt lake area, save foundation treatment costs, and shorten the foundation treatment period, it uses plastic drainage belts and gravel drainage cushion layers to form drainage channels, and then uses strong tamping technology to tamping and reinforce the saline soil foundation. The solution is slightly more difficult.

[0005] Based on the above-mentioned situation, technical personnel in this field need to develop a new solution with simpler process, higher construction convenience, good reinforcement effect and excellent economic effect.

[0006] In order to solve the above problems, people have been seeking an ideal technical solution. Summary of the invention

[0007] The purpose of the present invention is to address the deficiencies in the prior art and thereby provide a device and method for vibrating and compacting saline soil foundations which has simpler process, higher construction convenience, good reinforcement effect and excellent economic effect.

[0008] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a device for vibrating and compacting a saline soil foundation, comprising a walking device and a vibration unit;

[0009] The traveling device comprises a vehicle and a guide frame integrated on the vehicle, a high-pressure water pump, a lifting rope, a water pump, a hot water boiler, a thermal oil furnace and a control host;

[0010] The vibration unit includes a vibration hammer, a vibration rod and a vibration plate suspended on the guide frame through a lifting steel rope, the vibration rod and the vibration plate are switchably installed on the lower end action surface of the vibration hammer, and the vibration hammer includes a vibration exciter, a vibration-damping crossbeam and a vibration-damping spring;

[0011] The vibrating rod comprises a rod body and a wing edge, wherein a group of through holes extending along the length direction of the rod body and closed at the bottom end are arranged inside the rod body, and horizontally opened injection holes penetrating the through holes are evenly arranged on the surfaces of both sides of the rod body along the length direction; the through hole is connected to a high-pressure water pump through a hose, and the high-pressure water pump is connected to a hot water boiler, and is used to spray horizontal high-temperature jets into the soil to generate cracks in the soil and dissolve the soluble salt in the saline soil; the through hole is also connected to a water pump through a hose, and is used to pump away the water flow after the salt is dissolved;

[0012] The rod body of the vibration rod is also provided with a U-shaped channel distributed along the length direction, and the U-shaped channel is connected to the heat-conducting oil furnace for heating the vibration rod;

[0013] The vibration hammer is connected to the vibration rod to form a first vibration unit, which is used to vibrate and sink, retain vibration and vibrate and lift in the soil to achieve one-time vibration compaction, and spray horizontal high-temperature jets during the vibration retention process;

[0014] The vibration hammer is connected to the vibration plate to form a second vibration unit, which is used to perform secondary vibration compaction on the ground surface after the first vibration unit ends;

[0015] The control host is used to control the vibration frequency of the vibration hammer, and the working states of the high-pressure water pump, the water pump, the hot water boiler and the thermal oil furnace.

[0016] Based on the above, during the vibration process, the resonant frequency of the vibration rod-soil system is calculated by the following formula:

[0017]

[0018] Among them, the mass of the vibration rod and the exciter is m1, the mass of the vibration-damping beam is m2, the stiffness of the lifting rope is k1, the stiffness of the vibration-damping spring is k2, and the stiffness of the soil is k3.

[0019] Based on the above, during the vibration process, the resonant frequency of the vibration rod-soil system is calculated by the following formula:

[0020]

[0021] Among them, the mass of the vibration rod and the exciter is m1, the stiffness of the lifting rope is k1, and the stiffness of the soil is k3.

[0022] Based on the above, the number of the wing edges is four, and the four wing edges are symmetrically arranged on both sides of the vibration rod with a certain angle between each other.

[0023] Based on the above, a filter screen is installed in the injection hole; the vehicle is an engineering vehicle such as a crawler crane or a walking hydraulic vehicle.

[0024] A method for vibrating and compacting a saline soil foundation is implemented by using the device for vibrating and compacting a saline soil foundation and by the following steps:

[0025] Step 1) Lay out the vibration rod, determine and calibrate the vibration point of the vibration rod, connect the vibration hammer and the vibration rod, control the walking device to carry the vibration rod to the specified position, adjust the position of the guide frame and the lifting steel rope, so that the vibration rod is aligned with the hole to be processed and maintain verticality;

[0026] Step 2) Vibration sinking: Start the vibration hammer, release the lifting rope, and adjust the vibration frequency of the vibration hammer so that the vibration rod sinks into the soil layer along the guide frame under the action of high-frequency vertical vibration of 30Hz-50Hz until the designed depth;

[0027] Step 3) Bottom vibration retention: When the vibration rod sinks to the designed depth, adjust the vibration frequency of the vibration hammer to the resonance frequency of the vibration rod-soil system. At the same time, turn on the heat transfer oil furnace to allow the heat transfer oil to flow in the vibration rod; turn on the high-pressure water pump and the hot water boiler to inject high-pressure hot water into the through hole of the vibration rod. The high-pressure hot water is sprayed to the soil layer from the horizontally opened injection holes evenly distributed on the outer surface of both sides of the vibration rod, so that cracks are generated in the soil layer, and the soluble salt in the saline soil is dissolved, and a resonance compaction zone of the saline soil is formed. After the set time, the vibration and water spraying are stopped; then the water pump is turned on to pump out the water in the soil through the through hole of the vibration rod and the injection hole, so as to accelerate the dissipation of the excess pore water pressure generated by the vibration;

[0028] Step 4) Vibration lifting: After the vibration is completed, stop heating, water spraying and pumping, adjust the vibration frequency of the vibrating hammer, and lift the lifting steel rope so that the vibrating rod is gradually lifted to the ground under the high-frequency vertical vibration of 30Hz-50Hz;

[0029] Step 5) constructing the vibration points of the vibration rod in sequence according to the procedures of step 2) to step 4) until all the vibration points of the vibration rod are processed and a resonant dense superposition area is formed between adjacent vibration points;

[0030] Step 6) After all vibration points of the vibration rod are processed, remove the vibration rod and install the vibration plate at the lower end of the vibration hammer;

[0031] Step 7) Vibration plate laying out: determine and calibrate the vibration point position of the vibration plate, control the walking device to carry the vibration plate to the specified position, adjust the position of the guide frame and the lifting steel rope, place the vibration plate at the position to be processed and maintain verticality;

[0032] Step 8) Start the vibrating hammer, release the lifting rope, adjust the vibrating hammer to its highest frequency, vibrate until the soil layer no longer has obvious settlement, turn off the vibrating hammer, lift the lifting rope, and lift the vibration plate to the highest point;

[0033] Step 9) According to step 8), the vibration points of the vibration plate are constructed in sequence until all the vibration points of the vibration plate are processed; for areas with serious ground depression, soil is taken nearby and vibrated and compacted until it is parallel to the ground.

[0034] Based on the above, in step 3), the resonance frequency of the vibration rod-soil system during the vibration is calculated by the following formula:

[0035]

[0036] Among them, the mass of the vibration rod and the exciter is m1, the mass of the vibration-damping beam is m2, the stiffness of the lifting rope is k1, the stiffness of the vibration-damping spring is k2, and the stiffness of the soil is k3.

[0037] Based on the above, during the vibration process, the resonant frequency of the vibration rod-soil system is calculated by the following formula:

[0038]

[0039] Among them, the mass of the vibration rod and the exciter is m1, the stiffness of the lifting rope is k1, and the stiffness of the soil is k3.

[0040] Based on the above, in step 3), the vibration stage time is not less than 6 minutes, the water injection pressure range of the high-pressure water pump is controlled within the range of 0.5MPa-1.0Mpa, and the speed of lifting the vibration rod after vibration is ≤4m / min.

[0041] The present invention has outstanding substantive features and significant progress compared to the prior art. Specifically, the present invention has the following advantages:

[0042] 1. Use the vibrating rod to sink quickly to the set depth and then start the retained vibration. At the same time, use the high-pressure water pump, the through hole on the vibrating rod and the injection hole to produce a horizontal high-pressure hot water jet, so that cracks are generated in the soil layer and a horizontal water passage is formed. The high-pressure hot water can dissolve the soluble salts in the soil layer; the retained vibration frequency is controlled at the resonance frequency of the vibrating rod-soil system. The vibration energy can increase the length and width of the water passage. The heating of the vibrating rod by the hot oil can be transferred to the surrounding soil, reducing the heat loss of the hot water. During the vibration process, due to the design of the vibration frequency, the displacement difference between the vibrating rod and the soil is reduced, and the vibration is synchronized with the soil. The friction between the vibrating rod and the soil is increased, and the two are synchronized and vibrated. The vibration of the vibration is amplified, and then the vertical shear wave propagating outward along the axis of the vibration rod is used to optimally transfer the vibration energy to the surrounding saline soil. The soil particles are rearranged and consolidated. At the same time, the vibration rod also generates horizontal compression waves to squeeze and compact the surrounding soil, forming a resonance compaction zone of saline soil. During the process, the dissolved salt water gathers in the formed water passage. After a period of vibration and dissolution by high-pressure water jets, the water pump is started to pump out the salt water that dissolves the soluble salt, leaving the foundation with the soil as the main soil skeleton, completing a vibration compaction, which effectively solves a series of saline soil problems caused by the presence of soluble salts in saline soil, such as corrosion of steel bars, easy subsidence, and increase in soil volume due to salt expansion.

[0043] Furthermore, since salt easily accumulates on the surface, shallow compaction is increased to compensate for the defects of deep compaction by the vibrating rod. Therefore, after the first vibration compaction by the vibrating rod is completed, the vibrating plate is activated for secondary vibration compaction of the surface. Since the vibrating rod compaction method is a deep vibration compaction method, its compaction effect on shallow soil is general, while the vibration plate compaction is suitable for compacting shallow soil and completing the full compaction of saline soil foundation. In traditional solutions, shallow compaction requires the use of static rollers or vibrating rollers. The present application utilizes the same set of equipment to replace different working modes, realizes direct switching between the two vibration compactions, and thereby improves economy.

[0044] 2. In the process of compaction by vibrating rods, the saline soil foundation will experience complex stress condition changes. First, the vibrating rod will generate shear waves that propagate outward along the length of the rod, causing changes in the vertical stress conditions of the soil layer, and causing cyclic shear deformation and displacement of soil particles in the vertical direction; at the same time, the friction between the vibrating rod and the soil will generate horizontal compression waves and propagate to the surroundings, increasing the horizontal stress of the soil layer and thus squeezing and compacting it; the cyclic shear and seepage generated by high-pressure water spraying destroy the soil structure and squeeze the soil, and the cyclic shear significantly increases the horizontal stress of the soil layer, thereby improving the density of the soil, and can also increase the vibration response of the soil to promote the rearrangement of soil particles; at the same time, hot water seeps into the soil under the action of the pressure difference inside the soil and forms cracks, providing a horizontal drainage channel. The present invention combines the working principles of the two and chooses to adopt a combination of vibration and water spraying, which can significantly increase the horizontal stress of the soil and the vibration speed of soil particles compared to a single vibration condition, promote soil compaction and the dissolution of salt in the soil.

[0045] 3. The drainage method adopted by the present invention can use a water pump to form a low-pressure area in the hollow through hole of the vibration rod, so as to promote the pore water of the surrounding soil to flow to the hollow through hole of the vibration rod through the cracks of the soil layer. At the same time, the injection holes on the hollow through hole of the vibration rod can also be used to drain and consolidate soil layers of different depths. The filter screen can prevent larger particles from passing through. It effectively solves the problem that the brine cannot be discharged by the immersion pre-dissolution method, and is suitable for large-area saline soil foundation washing and compaction, with low cost, high efficiency and simple construction process.

[0046] 4. The device and method for vibrating and compacting saline soil foundation fully utilize the through-hole function of the vibrating rod, so that the through-hole of the vibrating rod can not only spray high-pressure hot water to the soil layer, but also extract the salt water in the soil in time, effectively avoiding the problem of the traditional method of treating saline soil foundation, which requires a long period of pre-dissolution by immersion, simplifies the construction procedure, and saves construction costs.

[0047] The device and method for vibrating and compacting saline soil foundation fully utilizes the vibrating and compacting device, so that the device can be connected to a vibrating rod to implement vibrating rod compaction, and can also be connected to a vibrating plate to implement vibrating plate compaction, effectively combining the advantages of the two vibrating and compacting methods, and can achieve compaction of the entire cross section of the soil, thereby reducing construction machinery and tools and saving construction costs.

[0048] In summary, the present invention is highly targeted at the reinforcement of saline soil, can significantly improve the effect and efficiency of saline soil reinforcement operations, and has a simple construction process, good economic advantages and promotion prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a structural schematic diagram of a device for vibrating and compacting saline soil foundation in the present invention, in which a vibrating rod is assembled.

[0050] Figure 2It is a working principle diagram of a device for vibrating and compacting saline soil foundation in the present invention, in which a vibrating rod is assembled.

[0051] Figure 3 It is a structural schematic diagram of a vibration plate assembled in a device for vibrating and compacting saline soil foundation in the present invention.

[0052] Figure 4 It is a working principle diagram of a device for vibrating and compacting saline soil foundation in the present invention, in which a vibration plate is assembled.

[0053] Figure 5 It is a schematic diagram of the structure of the vibration hammer in the present invention and its combination with the vibration rod.

[0054] Figure 6 It is a schematic diagram of the structure of the vibration hammer in the present invention and its combination with the vibration plate.

[0055] Figure 7 It is a structural schematic diagram of the vibration plate in the present invention.

[0056] In the figure: 1. hydraulic station; 2. water pump; 3. high-pressure water pump; 4. electric thermal oil furnace; 5. hot water boiler; 6. telescopic steel rope; 7. boom; 8. guide frame; 9. lifting steel rope; 10. vibrating hammer; 11. water injection port; 12. water extraction port; 13. thermal oil port; 14. water supply hose; 15. drainage hose; 16. thermal oil hose; 17. telescopic cross brace; 18. through hole; 19. injection hole; 20. vibrating rod; 21. U-shaped channel; 22. vibrating plate; 23. resonance compaction area; 24. soil layer cracks; 25. resonance compaction superposition area; 26. vibration plate compaction area; 221. plate surface; 222. reinforcing ribs. DETAILED DESCRIPTION

[0057] The technical solution of the present invention is further described in detail below through specific implementation methods.

[0058] like Figure 1 and Figure 3 As shown, a device for vibrating and compacting saline soil foundation comprises a walking device and a vibration unit.

[0059] The traveling device comprises a vehicle. The vehicle in this embodiment is an engineering vehicle such as a crawler crane or a walking hydraulic vehicle.

[0060] The vehicle is integrated with a hydraulic station 1, a water pump 2, a high-pressure water pump 3, an electric thermal oil furnace 4, a hot water boiler 5, a telescopic steel rope 6, a boom 7, a guide frame 8, a lifting steel rope 9 and a control host, and the control host is used to control the vibration frequency of the vibrating hammer 10, and the working state of the high-pressure water pump 3, the water pump 2, the hot water boiler 5 and the electric thermal oil furnace 4. The guide frame 8 is used to control the working position of the vibration rod 20 or the vibration plate 22. The guide frame 8 is arranged vertically and connected to the crawler crane through the boom 7 and the telescopic cross brace 17 in front of the vehicle head. The boom 7 can slide along the guide frame 8 and rotate through the telescopic steel rope 6, and the distance between the guide frame 8 and the crane is adjusted in combination with the telescopic cross brace 17.

[0061] The vibration unit includes a vibration hammer 10 suspended on a guide frame 8 through a lifting steel rope 9, a vibration rod 20 and a vibration plate 22. The vibration rod 20 and the vibration plate 22 can be switchably installed on the lower end action surface of the vibration hammer 10.

[0062] The vibration hammer 10 is a vibration device that can generate vertical vibration, and its vibration frequency range is 0 Hz to 50 Hz.

[0063] The vibration rod 20 includes a rod body and wing edges, wherein the number of the wing edges is four, and the four wing edges are symmetrically arranged on both sides of the vibration rod 20 with a certain angle between each other.

[0064] A group of through holes 18 extending along the length direction of the rod body and closed at the bottom end are arranged inside the rod body, and horizontal injection holes 19 that penetrate the through holes 18 are evenly arranged on the surfaces of both sides of the rod body along the length direction. In order to prevent large particles from clogging the pipeline, a filter is installed in the injection hole 19; the water injection port 11 of the through hole 18 is connected to the high-pressure water pump 3 through a water supply hose 14, and the high-pressure water pump 3 is connected to the hot water boiler 5, which is used to spray horizontal high-temperature jets into the soil to create cracks in the soil and dissolve the soluble salts in the saline soil. In this embodiment, the water injection pressure range of the high-pressure water pump 3 is controlled within 0.5MPa-1.0Mpa; the water suction port 12 of the through hole 18 is connected to the water pump 2 through a drainage hose 15, which is used to pump away the water flow after the salt is dissolved; the water injection port 11 and the water suction port 12 of the through hole 18 are both opened at the top of the through hole 18.

[0065] The rod body of the vibration rod 20 is also provided with a U-shaped channel 21 distributed along the length direction. The U-shaped channel 21 is connected to the electric thermal oil furnace 4 through the thermal oil hose 16, and is used to heat the vibration rod 20 as a whole. Its main purpose is to maintain the temperature of the vibration rod 20 and the temperature of the nearby soil, avoid excessive heat consumption of high-temperature water, and thereby ensure the performance of water jet dissolving salt.

[0066] The vibration hammer 10 is connected to the vibration rod 20 to form a first vibration unit, which is used for vibration sinking, vibration retention and vibration lifting in the soil to achieve one-time vibration compaction, and to spray horizontal high-temperature jets during the vibration retention process.

[0067] like Figure 6 As shown, the vibration hammer 10 is connected to the vibration plate 22 to form a second vibration unit, which is used to perform secondary vibration compaction on the ground surface after the first vibration unit ends.

[0068] like Figure 7 As shown, the vibration plate 22 includes a plate surface 221 and reinforcing ribs 222. The vibration plate is a solid manganese steel structure. The plate surface 221 is in the shape of a flat quadrangular pyramid without an upper bottom surface. The reinforcing ribs 222 are steel plates welded to the plate surface 221 in a criss-cross pattern so that the plate surface 221 can transmit the vibration of the vibration hammer 10.

[0069] The vibration hammer 10 is connected to the vibration rod 20 or the vibration plate 22 to drive the vibration of the vibration rod 20 or the vibration plate 22;

[0070] The guide frame 8 is used to control the working position of the vibration rod 20 or the vibration plate 22 .

[0071] The guide frame 8 is installed on the traveling device, the vibrating hammer is a hydraulic vibrating hammer, and the traveling device is correspondingly equipped with a hydraulic station. The vibrating hammer 10 is suspended on the guide frame 8 through a lifting rope 9, and the vibrating rod or vibrating plate is installed on the lower end of the vibrating hammer. The other end of the lifting rope 9 is installed on a crawler crane and is lifted and controlled by the crawler crane. The vibrating hammer 10 realizes variable frequency adjustment through the vehicle-mounted hydraulic station 1, which can cover the high frequency (30Hz-50Hz) and resonance frequency (15Hz-20Hz) required for the work, so as to optimize the sinking and pulling efficiency and the resonance compaction effect.

[0072] Specifically, the working steps of the above device are as follows, which are used to achieve vibration compaction reinforcement of saline soil foundation:

[0073] Before construction, preparation work needs to be done, the site needs to be leveled, and more prominent obstacles need to be removed before construction can begin.

[0074] Step 1) Lay out the vibration rod, determine and calibrate the vibration point of the vibration rod, connect the vibration hammer 10 and the vibration rod 20, control the walking device to carry the vibration rod 20 to the specified position, adjust the position of the guide frame 8 and the lifting steel rope 9, so that the vibration rod 20 is aligned with the hole to be processed and maintains verticality;

[0075] Step 2) Vibration sinking: Start the vibration hammer 10, release the lifting rope 9, adjust the vibration frequency of the vibration hammer 10, so that the vibration rod 20 is under the high-frequency vertical vibration of 30Hz-50Hz. In this embodiment, the maximum vibration frequency of the vibration hammer 10 is controlled at 50Hz. When vibrating and sinking, the vibration frequency is controlled at 40Hz, and sinks into the soil layer along the guide frame 8 until the designed depth;

[0076] Step 3) Bottom vibration retention: When the vibration rod 20 sinks to the designed depth, the vibration frequency of the vibration hammer 10 is adjusted to the resonance frequency of the vibration rod-soil system, wherein the resonance frequency of the vibration rod-soil system during the retention of vibration is calculated by the following formula:

[0077]

[0078] Among them, the mass of the vibration rod and the exciter is m1, the mass of the vibration-damping beam is m2, the stiffness of the lifting rope is k1, the stiffness of the vibration-damping spring is k2, and the stiffness of the soil is k3. It should be noted that the exciter is part of the vibration hammer, and the structure of the vibration-damping beam and the vibration-damping spring is shown in the attached figure. Figure 5 Generally speaking, this formula is a more accurate calculation formula and is used by designers when high precision is required.

[0079] In this embodiment, the resonance frequency is specifically set to 15 Hz-20 Hz, and 17 Hz is used in this embodiment.

[0080] At the same time, the electric heat-conducting oil furnace 4 is turned on to allow the heat-conducting oil to flow in the vibration rod 20, and the vibration rod 20 maintains a set temperature, mainly to prevent the water flow temperature from being lost.

[0081] Turn on the high-pressure water pump 3 and the hot water boiler 5, and inject high-pressure hot water into the through hole 18 of the vibration rod 20. The high-pressure hot water is sprayed toward the soil layer from the spray holes 19 evenly distributed horizontally on the outer surfaces of both sides of the vibration rod 20, so as to generate cracks in the soil layer, dissolve the soluble salt in the saline soil, and form a saline soil resonance compaction zone 23. After maintaining the set time, stop the vibration and water spraying. During the specific operation, the process of spraying and pumping water includes: turning on the hot water boiler 5, and after the water temperature rises to 100°C, turning on the high-pressure water pump 3, and injecting high-pressure hot water into the through hole 18 of the vibration rod 20 through the water supply hose 14 and the water injection port 11. The high-pressure hot water is sprayed from the injection holes 19 evenly distributed on the outer surface of the vibration rod 20 to the soil layer. 0.5Mpa-1.0Mpa high-pressure hot water is used. In this embodiment, 0.7Mpa is used to cause soil cracks 24 in the soil layer. After maintaining for 4 minutes, the vibration and water spraying are stopped, and the water pump 2 is turned on. The through hole 18 of the vibration rod 20 is connected through the drainage hose 15 and the water pumping port 12, and the water in the soil is pumped away from the injection holes 19 with a filter.

[0082] The heating process includes: opening and setting the electric heat-conducting oil furnace 4 , in this embodiment, the heat-conducting oil temperature is 300° C., and circulating the heat-conducting oil into the U-shaped channel 21 of the vibration rod 20 through the heat-conducting oil hose 16 and the heat-conducting oil port 13 .

[0083] like Figure 2 As shown, the generated resonance densification zone 23 is located between adjacent sinking holes, there are multiple soil cracks 24 with equal heights, and the resonance densification superposition zone 25 is located at the overlapping part of the resonance densification zone 23.

[0084] The overall vibration stage time is not less than 6 minutes, among which the water spraying time and water pumping time are designed to be not less than 4 minutes and not less than 2 minutes respectively.

[0085] In a preferred embodiment, during the vibration retention process, the resonance frequency of the vibration rod-soil system is calculated by the following formula:

[0086]

[0087] Among them, the mass of the vibration rod and the exciter is m1, the stiffness of the lifting rope is k1, and the stiffness of the soil is k3. Generally, this formula is a simplified formula to facilitate construction workers to calculate during the construction process.

[0088] Step 4) Vibration lifting: After the vibration is completed, stop heating, water spraying and pumping, adjust the vibration frequency of the vibration hammer 10, lift the lifting rope 9, and gradually lift the vibration rod 20 to the ground under the action of high-frequency vertical vibration of 30Hz-50Hz; the speed of lifting the vibration rod 20 is ≤4m / min, and 3.8m / min is used in this embodiment.

[0089] Step 5) The vibration points of the vibration rods are constructed in sequence according to the procedures of step 2) to step 4) until all the vibration points of the vibration rods are processed, and a resonant dense superposition area 25 is formed between adjacent vibration points. In this embodiment, the distance between adjacent vibration points is 1.5m, and the water passage can extend to the resonant dense superposition area 25.

[0090] Step 6) After all vibration points of the vibration rod are processed, the vibration rod 20 is removed and the vibration plate 22 is installed on the lower end of the vibration hammer 10.

[0091] Step 7) Vibration plate laying out: determine and calibrate the vibration point position of the vibration plate 22, control the walking device to carry the vibration plate 22 to the specified position, adjust the position of the guide frame 8 and the lifting rope 9, place the vibration plate 22 at the position to be processed and maintain verticality.

[0092] Step 8) Start the vibrating hammer 10, release the lifting rope 9, adjust the vibrating hammer 10 to its highest frequency, which is 50 Hz in this embodiment, and vibrate until the soil layer no longer has obvious settlement, then turn off the vibrating hammer 10, lift the lifting rope 9, and lift the vibration plate 22 to the highest point.

[0093] like Figure 4 As shown, step 9) constructs each vibration point of the vibration plate 22 in sequence according to step 8) until all vibration points of the vibration plate 22 are processed; for areas with severe ground depression, soil is taken nearby and vibrated and compacted until it is parallel to the ground. In this embodiment, the vibration plate 22 is arranged to completely cover the ground, and the width of the compacted point is equal to the side length of the vibration plate 22, that is, a spliced ​​arrangement. In the figure, the vibration plate compacted area 26 is in a state after surface vibration compaction.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should be included in the scope of the technical solution for protection of the present invention.

Claims

1. A device for vibrating and consolidating saline soil foundation, characterized in that: including a walking device and a vibration unit; The traveling device comprises a vehicle and a guide frame integrated on the vehicle, a high-pressure water pump, a lifting rope, a water pump, a hot water boiler, a thermal oil furnace and a control host; The vibration unit includes a vibration hammer, a vibration rod and a vibration plate suspended on the guide frame through a lifting steel rope, the vibration rod and the vibration plate are switchably installed on the lower end action surface of the vibration hammer, and the vibration hammer includes a vibration exciter, a vibration-damping crossbeam and a vibration-damping spring; The vibrating rod comprises a rod body and a wing edge, wherein a group of through holes extending along the length direction of the rod body and closed at the bottom end are arranged inside the rod body, and horizontally opened injection holes penetrating the through holes are evenly arranged on the surfaces of both sides of the rod body along the length direction; the through hole is connected to a high-pressure water pump through a hose, and the high-pressure water pump is connected to a hot water boiler, and is used to spray horizontal high-temperature jets into the soil to generate cracks in the soil and dissolve the soluble salt in the saline soil; the through hole is also connected to a water pump through a hose, and is used to pump away the water flow after the salt is dissolved; The rod body of the vibration rod is also provided with a U-shaped channel distributed along the length direction, and the U-shaped channel is connected to the heat-conducting oil furnace for heating the vibration rod; The vibration hammer is connected to the vibration rod to form a first vibration unit, which is used to vibrate and sink, retain vibration and vibrate and lift in the soil to achieve one-time vibration compaction, and spray horizontal high-temperature jets during the vibration retention process; The vibration hammer is connected to the vibration plate to form a second vibration unit, which is used to perform secondary vibration compaction on the ground surface after the first vibration unit ends; The control host is used to control the vibration frequency of the vibration hammer, and the working states of the high-pressure water pump, the water pump, the hot water boiler and the thermal oil furnace.

2. The device for vibrating and consolidating saline soil foundation according to claim 1, characterized in that: During the vibration process, the resonance frequency of the vibration rod-soil system is calculated by the following formula: Among them, the mass of the vibration rod and the exciter is m1, the mass of the vibration-damping beam is m2, the stiffness of the lifting rope is k1, the stiffness of the vibration-damping spring is k2, and the stiffness of the soil is k3.

3. The device for vibrating and consolidating saline soil foundation according to claim 1, characterized in that: During the vibration process, the resonance frequency of the vibration rod-soil system is calculated by the following formula: Among them, the mass of the vibration rod and the exciter is m1, the stiffness of the lifting rope is k1, and the stiffness of the soil is k3.

4. The device for vibrating and consolidating saline soil foundation according to claim 2 or 3, characterized in that: The number of the wing edges is four, and the four wing edges are symmetrically arranged on both sides of the vibration rod with a certain angle between each other.

5. The device for vibrating and consolidating saline soil foundation according to claim 4, characterized in that: A filter screen is installed in the injection hole; and the vehicle is a crawler crane or a walking hydraulic vehicle.

6. The device for vibrating and consolidating saline soil foundation according to claim 1, 2, 3 or 5, characterized in that: The vibration plate includes a plate surface and reinforcing ribs. The vibration plate is a solid manganese steel structure. The plate surface is in the shape of a flat quadrangular pyramid without an upper bottom surface. The reinforcing ribs are steel plates welded to the plate surface in a crisscross pattern so that the plate surface can transmit the vibration of the vibration hammer.

7. A method for consolidating saline soil foundation by vibration compaction, characterized in that: The device for vibrating and compacting saline soil foundation according to claim 1 is implemented by the following steps: Step 1) Lay out the vibration rod, determine and calibrate the vibration point of the vibration rod, connect the vibration hammer and the vibration rod, control the walking device to carry the vibration rod to the specified position, adjust the position of the guide frame and the lifting steel rope, so that the vibration rod is aligned with the hole to be processed and maintain verticality; Step 2) Vibration sinking: Start the vibration hammer, release the lifting rope, and adjust the vibration frequency of the vibration hammer so that the vibration rod sinks into the soil layer along the guide frame under the action of high-frequency vertical vibration of 30Hz-50Hz until the designed depth; Step 3) Bottom vibration retention: When the vibration rod sinks to the designed depth, adjust the vibration frequency of the vibration hammer to the resonance frequency of the vibration rod-soil system. At the same time, turn on the heat transfer oil furnace to allow the heat transfer oil to flow in the vibration rod; turn on the high-pressure water pump and the hot water boiler to inject high-pressure hot water into the through hole of the vibration rod. The high-pressure hot water is sprayed to the soil layer from the horizontally opened injection holes evenly distributed on the outer surface of both sides of the vibration rod, so that cracks are generated in the soil layer, and the soluble salt in the saline soil is dissolved, and a resonance compaction zone of the saline soil is formed. After the set time, the vibration and water spraying are stopped; then the water pump is turned on to pump out the water in the soil through the through hole of the vibration rod and the injection hole, so as to accelerate the dissipation of the excess pore water pressure generated by the vibration; Step 4) Vibration lifting: After the vibration is completed, stop heating, water spraying and pumping, adjust the vibration frequency of the vibrating hammer, and lift the lifting steel rope so that the vibrating rod is gradually lifted to the ground under the high-frequency vertical vibration of 30Hz-50Hz; Step 5) constructing the vibration points of the vibration rod in sequence according to the procedures of step 2) to step 4) until all the vibration points of the vibration rod are processed and a resonant dense superposition area is formed between adjacent vibration points; Step 6) After all vibration points of the vibration rod are processed, remove the vibration rod and install the vibration plate at the lower end of the vibration hammer; Step 7) Vibration plate laying out: determine and calibrate the vibration point position of the vibration plate, control the walking device to carry the vibration plate to the specified position, adjust the position of the guide frame and the lifting steel rope, place the vibration plate at the position to be processed and maintain verticality; Step 8) Start the vibrating hammer, release the lifting rope, adjust the vibrating hammer to its highest frequency, vibrate until the soil layer no longer has obvious settlement, turn off the vibrating hammer, lift the lifting rope, and lift the vibration plate to the highest point; Step 9) According to step 8), the vibration points of the vibration plate are constructed in sequence until all the vibration points of the vibration plate are processed; for areas with serious ground depression, soil is taken nearby and vibrated and compacted until it is parallel to the ground.

8. The method for consolidating saline soil foundation by vibration compaction according to claim 7, characterized in that: In step 3), the resonance frequency of the vibrating rod-soil system during the residual vibration is calculated by the following formula: Among them, the mass of the vibration rod and the exciter is m1, the mass of the vibration-damping beam is m2, the stiffness of the lifting rope is k1, the stiffness of the vibration-damping spring is k2, and the stiffness of the soil is k3.

9. The method for consolidating saline soil foundation by vibration compaction according to claim 7, characterized in that: During the vibration process, the resonance frequency of the vibration rod-soil system is calculated by the following formula: Among them, the mass of the vibration rod and the exciter is m1, the stiffness of the lifting rope is k1, and the stiffness of the soil is k3.

10. The method for consolidating saline soil foundation by vibration compaction according to claim 7, characterized in that: In step 3), the vibration stage lasts for no less than 6 minutes, and the water injection pressure range of the high-pressure water pump is controlled within a range of 0.5 MPa-1.0 MPa; in step 4), the speed of lifting the vibration rod after the vibration is ≤4 m / min.

Images