Soft foundation compacting and drainage reinforcing method combining high-pressure sand blasting pile and heaped loading
Through the combined loading and drainage consolidation technology of high-pressure spray sand piles, the pollution, high cost and limited reinforcement depth in the existing soft foundation reinforcement technology has been solved, and the compact reinforcement and drainage consolidation of soft soil foundations has been achieved, which has significantly improved the Physical and mechanical properties and construction efficiency.
Patent Information
- Application Number
- CN202411185671.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-27
- Publication Date
- 2024-12-13
AI Technical Summary
The existing soft-based reinforcement technology has problems such as environmental pollution, high costs, limited reinforcement depth and complex processes, and it is difficult to effectively improve the physical and mechanical characteristics of weak soil layers, especially when the sludge layer thickness is less than 8m, the pre-pressure effect is poor.
Using the combined loading method of high-pressure spray sand piles, by drilling holes in the soft soil foundation and high-pressure spin spraying into piles, vertical sand columns, transverse expanded sand piers or split sand belts, combined with drainage cushion layer and filter pipes to achieve compact reinforcement and drainage consolidation of soft foundation.
The dual effects of compact reinforcement and drainage consolidation of soft soil foundations have been achieved, which significantly improves the physical and mechanical properties of soft soil foundations, improves the reinforcement effect and construction efficiency, reduces environmental pollution and costs, and is suitable for different soil layers.
Smart Images
Figure CN119121902A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of soft soil foundation reinforcement, and in particular relates to a soft soil foundation compaction and drainage reinforcement method using high-pressure jet sand piles combined with stacking. Background Art
[0002] In the process of engineering construction, the reinforcement of soft soil foundation is an important factor affecting the comprehensive construction quality of engineering construction. Since soft soil foundation has the characteristics of high water content and poor bearing capacity, if it cannot be scientifically and reasonably managed, it will cause safety risks to varying degrees.
[0003] At present, my country has made some achievements in the practical application and theoretical research of soft foundation reinforcement, such as high-pressure rotary jet pile reinforcement method, drainage consolidation method, dynamic tamping (replacement) method, etc. Various methods have their own advantages and disadvantages in terms of applicable soil layers, efficiency, reinforcement effects, etc. For example, the high-pressure rotary jet pile reinforcement method uses a high-pressure rotating nozzle to spray cement slurry into the soil layer and mix it with the soil to form a cement reinforced pile body. The construction occupies a small area, has low vibration and low noise, but has disadvantages such as environmental pollution, high cost and small scope of application; the drainage consolidation method has the advantages of short construction period and obvious reinforcement effect, but the process is complicated, the cost is high, the preloading effect is subject to certain limitations, and the reinforcement depth is limited. The preloading effect is better when the silt layer thickness is less than 8m. When there is a sand layer in the silt, a sealing wall needs to be added around it.
[0004] Therefore, there are still many problems and challenges in the application and development of soft foundation reinforcement technology, and there is still a long way to go in the research of new soft foundation reinforcement technology. In order to seek a soft foundation reinforcement method that can quickly and efficiently improve the physical and mechanical properties of soft soil layers, a soft foundation compaction and drainage reinforcement method of high-pressure jet sand piles combined with loading is proposed. Summary of the invention
[0005] The present invention mainly aims to overcome the deficiencies of the prior art and provides a soft foundation compaction and drainage reinforcement method by combining high-pressure jet sand piles with heap loading.
[0006] The present invention is achieved through the following technical solutions:
[0007] A soft foundation compaction and drainage reinforcement method using high-pressure jet sand piles combined with heap loading, comprising the following steps:
[0008] Step 1: First, the site is leveled, then soft foundation exploration is carried out to find out the geological structure of the soft soil foundation to be treated, and then the drainage cushion layer of the lower layer is laid;
[0009] Step 2: measure the placement points and put the pile system in place;
[0010] Step 3: Use the pile-forming system to first drill holes at the pile-forming points, and then perform high-pressure jetting pile construction to construct high-pressure jet sand piles;
[0011] The pile-forming effect of the pile-forming system in the foundation depends on the strength of each soil layer. After drilling a hole in the soft soil foundation, a vertical sand column will be formed after high-pressure rotary jetting, and the sand column will extend upward to the surface of the soft soil foundation. For the silty soil layer, an expanded sand mound will be formed on the sand column of the high-pressure sand-jetted pile, and the expanded sand mound is a horizontally continuous mound-shaped structure connected to the sand column; for the soil layer with harder soil conditions, a splitting sand belt will be formed on the sand column of the high-pressure sand-jetted pile, and the splitting sand belt is a horizontally extending belt-shaped structure connected to the sand column; in order to achieve a better pile-forming effect, the pile-forming system is controlled during the high-pressure rotary jetting pile construction. For the silty soil layer in the proven soft soil foundation, the sand blasting flow rate and sand blasting pressure of the pile-forming system are increased compared to the hard soil layer. At the same time, the sand blasting residence time of the pile-forming system in the silty soil layer is prolonged, so that a larger expanded sand mound is formed in the silty soil layer;
[0012] Step 4: Spread the upper drainage cushion layer, and lay the water filter pipe in the drainage cushion layer;
[0013] Step 5: laying geotextile on the drainage cushion layer, leading out the filter pipe in the drainage cushion layer and connecting it to the drainage system;
[0014] Step six, pile up materials on the geotextile step by step to preload and drain the soft soil foundation.
[0015] In the above technical solution, the pile forming system includes a high-pressure mortar mixing pump, a circulation pipeline and a drilling and spraying machine. The high-pressure mortar mixing pump needs to circulate and stir the mortar; the drilling and spraying machine is connected to the circulation pipeline, and the mortar is provided to the drilling and spraying machine through the circulation pipeline.
[0016] In the above technical solution, the drainage cushion layer is a thick sand cushion layer.
[0017] The advantages and beneficial effects of the present invention are:
[0018] (1) The present invention combines the advantages of the high-pressure jet grouting pile reinforcement method and the drainage consolidation method, and combines the high-pressure jet sand pile with the preloading to achieve the double reinforcement effect of compaction reinforcement and drainage consolidation for the soft soil foundation, which can effectively improve the physical and mechanical properties of the soft soil foundation and provide effective guarantee for the safety, quality and progress of subsequent engineering construction.
[0019] (2) The present invention proposes for the first time the construction process of "high-pressure sand jetting piles". The high-pressure sand jetting piles themselves have the function of improving the bearing capacity of soft foundations. The sand columns, expanded sand piers, and split sand belts improve the soil quality and density of the soft soil layer to varying degrees, and can provide an ideal spatial drainage channel for deep soft foundation reinforcement. Under the action of drainage and consolidation, secondary reinforcement of the soft foundation is achieved. In particular, the formation of the split sand belt provides a horizontal drainage channel for the soil layer outside the influence of the high-pressure sand jetting piles, effectively improving the drainage and consolidation effect and process of the soft foundation.
[0020] (3) The present invention is developed for soft foundations with poor soil conditions, and has an obvious reinforcement effect. It can replace or improve extremely soft soil layers more thoroughly, and the reinforcement effect on silty soft soil is more obvious. The introduction of high-pressure jet sand piles solves the problems of traditional high-pressure rotary jet piles that pollute the environment and are high in cost. The combined drainage consolidation method and the dynamic compaction method have the advantages of good reinforcement effect, high construction efficiency, and environmental protection.
[0021] (4) During the high-pressure rotary jet grouting construction, the pile-forming effect of the pile-forming system in the foundation depends on the strength of each soil layer. However, the physical and mechanical properties of the soft soil layer to be treated are unknown, so the pile-forming effect is passive. Therefore, the present invention controls the pile-forming system during the high-pressure rotary jet grouting construction. For the silty soil layer in the proven soft soil foundation, the sandblasting flow rate and sandblasting pressure of the pile-forming system are increased compared to the hard soil layer. At the same time, the sandblasting residence time of the pile-forming system in the silty soil layer is prolonged, so that a larger expanded sand mound is formed in the silty soil layer, thereby being able to carry out targeted and active pile-forming control corresponding to different soil layers, achieving a better pile-forming effect, and thus having a better compaction and reinforcement effect on the soft soil foundation. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a schematic diagram of the structure of the present invention.
[0023] Figure 2 This is a structural diagram of the pile system.
[0024] In the figure, there are an expanded sand pier 11, a splitting sand belt 12, a sand column 13, a drainage cushion layer 2, a pile loading material 3, a pile forming system 4, a high-pressure mortar mixing pump 41, a circulation pipeline 42, and a drilling and spraying machine 43.
[0025] For ordinary technicians in this field, other relevant drawings can be obtained based on the above drawings without any creative work. DETAILED DESCRIPTION
[0026] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is further described below in conjunction with specific embodiments.
[0027] A soft foundation compaction and drainage reinforcement method using high-pressure jet sand piles combined with heap loading, comprising the following steps:
[0028] Step 1: First, the site is leveled, then soft foundation exploration is carried out to find out the geological structure of the soft soil foundation to be treated, and then the drainage cushion layer 2 of the lower layer is laid;
[0029] Step 2: measure the placement points and put the pile system in place 4;
[0030] The pile forming system 4 includes a high-pressure mortar mixing pump 41, a circulation pipeline 42 and a drilling and spraying machine 43. The high-pressure mortar mixing pump 41 needs to circulate and stir the mortar material to prevent the mortar material from settling and being unable to be sucked into the circulation pipeline 42, thereby affecting the pile forming effect and quality; the drilling and spraying machine 43 is connected to the circulation pipeline 42, and the mortar material is provided to the drilling and spraying machine 43 through the circulation pipeline 42;
[0031] Step 3: using the pile forming system 4, first drilling holes at the pile forming points, and then performing high-pressure jetting pile forming construction to construct high-pressure jet sand piles 1;
[0032] The pile-forming effect of the pile-forming system 4 in the foundation depends on the strength of each soil layer. After drilling, a vertical sand column 13 will be formed on the soft soil foundation after high-pressure rotary spraying. The sand column 13 extends upward to the surface of the soft soil foundation. For silty soil layers, an expanded sand pier 11 will be formed on the sand column 13 of the high-pressure jet sand pile 1. The expanded sand pier 11 is a horizontally continuous pier-shaped structure connected to the sand column 13. The larger the expanded sand pier 11, the better the compaction and reinforcement effect on the soft soil foundation. For soil layers with harder soil conditions, a splitting sand belt 12 will be formed on the sand column 13 of the high-pressure jet sand pile 1. The splitting sand belt 12 is a water-jet sand belt connected to the sand column 13. The horizontally extending strip structure can increase the horizontal contact range between the high-pressure jet sand pile 1 and the soft soil foundation, form a horizontal drainage channel, and improve the horizontal drainage effect; in order to achieve a better pile forming effect, the pile forming system 4 is controlled during the high-pressure jetting pile forming construction, and the sandblasting flow rate and sandblasting pressure of the pile forming system 4 are increased for the muddy soil layer in the proven soft soil foundation compared to the hard soil layer. At the same time, the sandblasting residence time of the pile forming system 4 in the muddy soil layer is prolonged, so that a larger expanded sand pier 11 is formed in the muddy soil layer, thereby improving the compaction and reinforcement effect on the soft soil foundation;
[0033] Step 4: Spread the upper drainage cushion layer 2, and lay the water filter pipe in the drainage cushion layer 2;
[0034] Step 5: laying geotextile on the drainage cushion layer 2, leading out the filter pipe in the drainage cushion layer 2 and connecting it to the drainage system;
[0035] Step 6, stacking material 3 on the geotextile step by step to preload and drain the soft soil foundation;
[0036] After the drainage cushion layer 2 is loaded with the pile material 3, the water in the soil layer within the influence range of the sand column 13 is discharged upward into the drainage cushion layer 2 using the sand column 13 as a vertical drainage channel, and finally discharged into the drainage system from the filter pipe in the drainage cushion layer 2; the water in the soil layer within the influence range of the expanded sand pier 11 enters the expanded sand pier 11, and then enters the sand column 13, and then uses the sand column 13 as a vertical drainage channel to discharge upward into the drainage cushion layer 2, and finally discharges into the drainage system from the filter pipe in the drainage cushion layer 2; the water in the soil layer outside the influence range of the sand column 13 and the expanded sand pier 11 uses the splitting sand belt 12 as a horizontal drainage channel, and then enters the sand column 13, and then uses the sand column 13 as a vertical drainage channel to discharge upward into the drainage cushion layer 2, and finally discharges into the drainage system from the filter pipe in the drainage cushion layer 2; thereby achieving a more uniform drainage and consolidation effect on the soft soil foundation.
[0037] For ease of explanation, spatial relative terms such as "upper", "lower", "left", "right" and the like are used in the embodiments to illustrate the relationship of one element or feature shown in the figure relative to another element or feature. It should be understood that, in addition to the orientation shown in the figure, the spatial terms are intended to include different orientations of the device in use or operation. For example, if the device in the figure is inverted, the element described as being "under" other elements or features will be positioned "on" other elements or features. Therefore, the exemplary term "under" can include both upper and lower orientations. The device can be positioned in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used here can be interpreted accordingly.
[0038] Furthermore, relational terms such as “first” and “second” and the like are merely used to distinguish one component from another having the same name, but do not necessarily require or imply any such actual relationship or order between these components.
[0039] The above is an exemplary description of the present invention. It should be noted that, without departing from the core of the present invention, any simple deformation, modification or other equivalent invention that can be made by those skilled in the art without expending creative labor falls within the protection scope of the present invention.
Claims
1. A soft foundation compaction and drainage reinforcement method using high-pressure sand jetting piles combined with heap loading, comprising the following steps: Step 1: First, the site is leveled, then soft foundation exploration is carried out to find out the geological structure of the soft soil foundation to be treated, and then the drainage cushion layer of the lower layer is laid; Step 2: measure the placement points and put the pile system in place; Step 3: Use the pile-forming system to first drill holes at the pile-forming points, and then perform high-pressure jetting pile construction to construct high-pressure jet sand piles; The pile-forming effect of the pile-forming system in the foundation depends on the strength of each soil layer. After drilling a hole in the soft soil foundation, a vertical sand column will be formed after high-pressure rotary jetting, and the sand column will extend upward to the surface of the soft soil foundation. For the silty soil layer, an expanded sand mound will be formed on the sand column of the high-pressure sand-jetted pile, and the expanded sand mound is a horizontally continuous mound-shaped structure connected to the sand column; for the soil layer with harder soil conditions, a splitting sand belt will be formed on the sand column of the high-pressure sand-jetted pile, and the splitting sand belt is a horizontally extending belt-shaped structure connected to the sand column; in order to achieve a better pile-forming effect, the pile-forming system is controlled during the high-pressure rotary jetting pile construction. For the silty soil layer in the proven soft soil foundation, the sand blasting flow rate and sand blasting pressure of the pile-forming system are increased compared to the hard soil layer. At the same time, the sand blasting residence time of the pile-forming system in the silty soil layer is prolonged, so that a larger expanded sand mound is formed in the silty soil layer; Step 4: Spread the upper drainage cushion layer, and lay the water filter pipe in the drainage cushion layer; Step 5: laying geotextile on the drainage cushion layer, leading out the filter pipe in the drainage cushion layer and connecting it to the drainage system; Step six, pile up materials on the geotextile step by step to preload and drain the soft soil foundation.
2. The soft foundation compaction and drainage reinforcement method of high-pressure jet sand pile combined with heap loading according to claim 1 is characterized by: The pile forming system comprises a high-pressure mortar mixing pump, a circulation pipeline and a drilling and spraying machine. The high-pressure mortar mixing pump is required to circulate and stir the mortar material; the drilling and spraying machine is connected to the circulation pipeline, and the mortar material is provided to the drilling and spraying machine through the circulation pipeline.
3. The soft foundation compaction and drainage reinforcement method of high-pressure jet sand pile combined with heap loading according to claim 1 is characterized by: The drainage cushion layer is a thick sand cushion layer.