Novel screw hole-forming insertion single body and composite precast pile forming construction method
By using screw pile mechanical rotation extrusion hole forming and composite precast pile construction methods, the problems of pollution, noise, soil squeezing effect and cost in traditional pile foundation construction have been solved, achieving efficient and environmentally friendly pile foundation construction results.
Patent Information
- Application Number
- CN202510941406.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-09
- Publication Date
- 2025-10-17
AI Technical Summary
Traditional pile foundation construction methods suffer from problems such as mud pollution, difficulty in cleaning slag at the pile bottom, unstable pile quality, high noise, severe soil squeezing effect, and high cost, especially when traversing hard soil layers where efficiency is low.
The screw pile is mechanically rotated and extruded to form a hole, and cement slurry or fine stone concrete is injected simultaneously. Precast piles are inserted and secondary grouting treatment is carried out to form a composite pile body. The construction parameters are adjusted in real time according to the geological conditions to optimize the interface treatment.
It has achieved efficient, low-carbon and environmentally friendly pile foundation construction under complex geological conditions, with the pile bearing capacity increased by 30%-50%, noise reduced, material consumption reduced, cost reduced, and environmental impact minimized.
Smart Images
Figure CN120797650A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of civil engineering pile foundation construction, in particular to a new type of screw hole forming insertion monomer and composite precast pile pile forming method. BACKGROUND
[0002] Traditional pile foundation methods such as impact and bored pile have problems such as mud pollution, difficulty in cleaning the pile bottom, unstable pile body quality, and relatively low pile side and pile end bearing capacity; precast pile hammering or static pressure construction has problems such as loud noise, serious soil squeezing effect, and difficulty in penetrating hard soil layers such as sand and gravel; existing precast pile planting methods have problems such as difficulty in entering rock, low efficiency when penetrating hard soil layers such as sand and gravel, large amount of grouting, uneven cement soil mixing, unstable strength, and high cost.
[0003] At present, the domestic extrusion type pile forming method includes static pressure (hammering) pile and screw pile; among them, the static pressure (hammering) pile is a precast pile, which has fast construction speed and high economic efficiency, but has the disadvantage of difficulty in sinking when encountering hard and complex stratum, and serious soil squeezing effect due to the full extrusion characteristics; the screw pile has significantly reduced soil squeezing effect around the hole due to its rotation hole forming.
[0004] In view of the above status of pile foundation engineering, the advantages of no mud, no noise, and no sediment during the screw pile hole forming process, high construction efficiency when entering the moderately weathered rock, and the characteristics of high strength concrete of the precast pile are combined to form a new type of screw hole forming insertion monomer and composite precast pile method, which can adapt to various complex geological conditions, has high construction efficiency, small environmental impact, obvious economic benefit, and truly realizes a new type of pile foundation method with optimal comprehensive performance such as green, low carbon, environmental protection, and energy saving. SUMMARY
[0005] The present application aims to provide a new type of screw hole forming composite precast pile insertion monomer and composite precast pile pile forming method which can adapt to various complex geological conditions, effectively reduce construction cost, and realize low carbon, green and environmental protection.
[0006] To achieve the above technical purposes, the technical solutions adopted by the present application are as follows:
[0007] The new type of screw hole forming insertion monomer and composite precast pile pile forming method comprises the following steps:
[0008] Step 1: the screw pile is mechanically rotated and extruded to form a hole, and cement slurry, fine stone concrete or solidified soil medium is injected into the bottom of the pile at the same time when the drill pipe is pulled out;
[0009] Step 2: after injecting the cement slurry, fine stone concrete or solidified soil medium, the precast pile is inserted or planted into the pile hole, and the precast pile is sunk to the designed position by static pressure or secondary spinning pressure;
[0010] Step 3, secondary grouting treatment is performed on the pile side to form a composite pile body with the surrounding soil.
[0011] Preferably, in step 1, the reasonable difference between the hole diameter formed by the screw and the outer diameter of the prefabricated pile can be in the range of -50-200mm.
[0012] Preferably, in step 2, before the prefabricated pile is inserted, the surface of the hole wall is provided with deep threads, shallow threads, or rough surface shapes after extrusion according to the characteristics of the soil layer to enhance the interfacial friction.
[0013] Preferably, the types of the monomer and the prefabricated pile are PHC pipe pile, or bamboo joint pile, or square pile, or special-shaped pile, or steel pipe pile, and the concrete strength grade of the pile body is ≥C60.
[0014] If necessary, preferably, in step 2, cement slurry, fine stone concrete or solidified soil medium is injected, the medium is cement-based material or high polymer, and the injection amount is 10%-50% of the hole volume.
[0015] Preferably, the construction method device further comprises a screw pressurizing system, a synchronous and non-synchronous intelligent electrical control system, and the screw drilling tool rotation speed, torque and pressure are adjusted in real time according to the geological conditions to realize the designed hole forming.
[0016] Preferably, the construction method is suitable for backfill soil, soft soil, sand layer, gravel layer and medium weathered rock layer, the pile length range is 6-80m, and the single pile ultimate bearing capacity standard value is 3000-25000kN.
[0017] By adopting the technical scheme of the application, the construction method forms a hole by mechanical rotation and extrusion of the screw pile, synchronously injects cement slurry or fine stone concrete at the bottom of the pile, and if necessary, injects a solidifying agent to reinforce the soil body of the hole; then, the prefabricated pile is inserted and implanted and the interface treatment is optimized to form a composite pile body that cooperatively bears stress. The texture roughening treatment or the bonding medium is set to improve the pile-soil friction; the construction parameters are adjusted in real time based on the geological parameters to ensure the pile forming quality.
[0018] Compared with the prior art, the application realizes the combination of the high frictional resistance of the screw thread and the high strength of the prefabricated pile, the compression bearing capacity is improved by 30%-50%, the bearing layer is suitable for hard clay, gravel layer and medium weathered rock layer, the pile body damage rate is reduced, there is no mud discharge, the noise is ≤65dB, the construction period is shortened, the material consumption is reduced, and the comprehensive cost is reduced. BRIEF DESCRIPTION OF DRAWINGS
[0019] The application can be further illustrated by the non-limiting embodiments shown in the drawings;
[0020] Figure 1 It is a schematic diagram of the new screw hole forming and insertion monomer and composite prefabricated pile pile forming method of the application. DETAILED DESCRIPTION
[0021] In order to enable those skilled in the art to better understand the present invention, the technical solution of the present invention is further described below with reference to the accompanying drawings and embodiments.
[0022] like Figure 1 As shown in the figure, A is the first step, where the screw pile machine rotates and squeezes to form a hole. B is the second step, where the drill is lifted to form a hole. C is the third step, where the prefabricated pile is statically pressed (hammered or vibrated). D is the fourth step, where the pile is composited. Among them, E is the screw pile machine, F is the pile driving machine, G is the ground elevation, and H is the concrete or mortar.
[0023] Example
[0024] This embodiment provides a novel method for constructing a pile by inserting a screw into a single body and a composite prefabricated pile, specifically, for construction in a soft soil layer.
[0025] Geological conditions: The surface layer is a 5m thick pond slag backfill layer, the lower layer is a 9m thick silty clay (the standard value of the ultimate side resistance qsik = 60kPa), the strongly weathered layer is 1m (qsik = 120kPa, qpk = 6000kPa), the pile end bearing layer is moderately weathered sandstone (qpk = 18000kPa), and the rock penetration is 1m.
[0026] Construction parameters:
[0027] Screw hole forming stage:
[0028] Equipment: integrated screw drilling rig equipped with intelligent control system;
[0029] Hole diameter 600mm (same as the outer diameter of precast piles);
[0030] Curing agent: cement slurry (water-cement ratio 0.5), injection volume 20%.
[0031] Precast pile implantation stage:
[0032] Precast pile type: PHC pipe pile (outer diameter 600mm, wall thickness 150mm, C105 concrete), pile length 16m; implantation method: static pressure, pressure 3000kN.
[0033] Total bearing capacity of composite pile:
[0034] Q u =Q sk +Q pk =1345+5086=6431kN (actual measured force: 9000kN, settlement: 18mm)
[0035] Comparative Example 1
[0036] Pure screw pile construction (1 meter into the medium weathered layer)
[0037] Qu = Q sk + Q pk = 1345 + 5086 = 6431 kN (measured 7600 kN, settlement 16 mm)
[0038] Comparative Example 2
[0039] Traditional bored pile (1 m into the weathered layer)
[0040] Qu = Q sk + Q pk = 1243 + 3560 = 4803 kN (measured 5200 kN, settlement 36 mm).
[0041] Comparison of Theoretical and Measured Values of Bearing Capacity of Each Pile Type
[0042]
[0043] From the comparison of the theoretical and measured values of the bearing capacity of each pile type, the theoretical ultimate bearing capacity of the 600 screw composite super-high strength pipe pile is 6582 kN, the measured ultimate bearing capacity is 9000 kN (reaching the limit of the strength of the super-high strength concrete pipe pile), the settlement is 18 mm, and the foundation soil has not been damaged. The test shows that if the pile strength is increased, the bearing capacity can be further improved. The theoretical calculation value is less than the measured value, indicating that the rock-soil side resistance coefficient and the end resistance coefficient are on the safe side, and the side resistance of the top 5 meters of backfilling stone slag also plays a certain role in the measured stage.
[0044] From the results of the 600 screw pile, the theoretical ultimate bearing capacity is 6582 kN, the measured ultimate bearing capacity is 7600 kN (reaching the limit of the strength of the concrete pile), the settlement is 16 mm, and the foundation soil has not been damaged. The test shows that if the pile strength is increased, the bearing capacity can be further improved.
[0045] From the results of the 600 bored pile, the rock-embedded depth is 1 m (the rock drilling efficiency is low); the bearing capacity is 5200 kN (settlement 36 mm); this is due to the mud walling leading to pile end sedimentation, weakening the end resistance; the mud treatment cost increases by 20%, and the noise is ≥ 75 dB.
[0046] Further comparison, the composite method improves the bearing capacity by 15%-36% through interface coordination and end resistance correction, reduces the settlement by 40%-50%, shortens the construction period by 20%-40%, has no mud discharge, optimizes the materials, and reduces the comprehensive cost by 15%-30%
[0047] From the analysis of the above examples and comparative examples, it can be seen that the unique form of the screw thread drill of the screw pile and the construction process characteristics of the screw pile technology can better improve the structural stress of the surrounding geology of the pile body, increase the friction coefficient, and improve the overall bearing capacity; the composite pile body combines the high friction resistance of the screw pile and the high strength of the pipe pile, and compared with a single pile type, the bearing capacity is significantly improved, which can meet the high requirements of high-rise buildings, large bridges and other engineering on foundation bearing capacity and settlement.
[0048] Under complex geological conditions such as soft soil layer and sand layer, the pre-reinforcement of the soil body by the screw pile hole forming reduces the difficulty of pipe pile insertion and implantation, and reduces the risk of pile body damage during pile sinking.
[0049] The construction process does not discharge mud, has small noise and vibration, and is friendly to the surrounding environment, especially suitable for engineering construction in urban center areas.
[0050] Further, the integrated construction process and efficient equipment operation greatly shorten the construction period and reduce labor and equipment rental costs. Due to the improvement of the bearing capacity of the composite pile body, the number and length of the piles can be appropriately reduced, and the amount of concrete, steel and other materials can be reduced.
[0051] The new method discards the mud wall protection process in traditional pile foundation construction, reduces the mud treatment link, and reduces the generation of construction waste; the surrounding soil is relatively small during construction, which can effectively reduce the soil squeezing effect, and the low noise and low vibration construction characteristics can effectively reduce the influence on the surrounding residents and the ecological environment.
[0052] The construction process is relatively simple, and the pile insertion and implantation in the existing pile hole are convenient to operate, which can save some construction time and cost; the site conditions are relatively low, and the construction can be carried out in some narrow space or complex environment around existing buildings; the applicable geological conditions are relatively wide, and it has good adaptability in sand, clay and other soil layers.
[0053] The new method has broad application prospects in the fields of building, transportation, energy and other fields. With the acceleration of urbanization and the continuous advancement of infrastructure construction, the requirements for pile foundation technology are increasing. With its technical, economic and environmental advantages, this method is expected to become one of the mainstream technologies for pile foundation construction under complex geological conditions. In the future, long-term performance research on this method can be further carried out, the construction equipment and process can be optimized, and its application range can be expanded, so as to provide more reliable and efficient foundation solutions for engineering construction.
[0054] It should be noted that the above examples are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described with reference to the preferred embodiments, it should be understood by those of ordinary skill in the art that the technical solutions of the present application can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present application, and they should be covered in the scope of the claims of the present application.
[0055] The new screw hole-forming insertion monomer and composite precast pile pile-forming method provided by the present application are described in detail above. The specific examples and comparative examples are only used to help understand the method of the present application and its core idea. It should be pointed out that for ordinary skilled persons in the technical field, some improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.
Claims
1. A new type of screw hole insertion and composite prefabricated pile construction method, characterized by The following steps are involved: Step 1: Use a screw pile machine to rotate and squeeze into a hole, and inject cement slurry, fine stone concrete or solidified soil medium into the pile bottom while lifting the drill rod; Step 2: After injecting cement slurry, fine stone concrete or solidified soil medium, insert or implant the precast pile into the pile hole, and use static pressure or secondary spinning to sink the precast pile to the designed position; Step 3: Perform secondary grouting on the pile side to form a composite pile body with the surrounding soil.
2. The novel screw hole insertion monomer and composite prefabricated pile construction method according to claim 1 is characterized by: In step 1, a reasonable difference between the screw hole diameter and the outer diameter of the precast pile can be in the range of -50-200 mm.
3. The novel screw hole insertion and composite prefabricated pile construction method according to claim 2 is characterized by: In step 2, before the prefabricated pile is inserted and implanted, the hole wall surface is provided with deep threads, shallow threads, or a rough surface shape after extrusion according to the characteristics of the soil layer to enhance the interface friction.
4. The novel screw hole insertion and composite prefabricated pile construction method according to claim 3 is characterized by: The types of the monomer and prefabricated piles are PHC pipe piles, bamboo piles, square piles, special-shaped piles, or steel pipe piles, and the strength grade of the pile body concrete is ≥C60.
5. The novel screw hole insertion monomer and composite prefabricated pile construction method according to claim 4 is characterized by: In step 2, cement slurry, fine stone concrete or solidified soil medium is injected, the medium is a cement-based material or a high molecular polymer, and the injection amount is 10%-50% of the pore volume.
6. The novel screw hole insertion and composite prefabricated pile construction method according to claim 5 is characterized by: The method equipment also includes: a screw pressurizing system, a synchronous and asynchronous intelligent electrical control system, which adjusts the screw drilling tool speed, torque and pressure in real time according to geological conditions to achieve designed drilling.
7. The novel method for forming piles by inserting screw holes into monomers and composite prefabricated piles as claimed in claim 6, characterized in that: The method is applicable to backfill soil, soft soil, sand layer, gravel layer and moderately weathered rock layer. The pile length range is 6-80m, and the standard value of the ultimate bearing capacity of a single pile is 3000-25000kN.