CN202865831U - Cast-in-place hexagonal or octagonal immersed tube poured concrete hollow pile - Google Patents

Abstract

The utility model provides a cast-in-place hexagonal or octagonal immersed tube poured concrete hollow pile. The cross section of a concrete hollow pile body is in a hexagonal or octagonal shape. A reinforcement cage is arranged or not arranged in the pile body. A post-cast seal opening pile cap which is arranged at the top of the pile body and a precast reinforced concrete pile tip which is arranged at the bottom of the pile body are arranged in the pile body. The upper portion of the pile tip is provided with an outer hexagonal or octagonal inner circle hollow flange, the lower portion of the pile tip is an outer hexagonal or octagonal inner circle hollow annular cone body, and a hexagonal or octagonal inner circle type hollow pile is formed. The utility model further provides a construction method for the cast-in-place hexagonal or octagonal immersed tube poured concrete hollow pile. The cast-in-place hexagonal or octagonal immersed tube poured concrete hollow pile has the advantages of enabling the bearing capacity of a single pile supplied by the resistance of pile periphery soil and pile tip soil to be basically close to a design value of pile body axle load strength and being good in price performance ratio, long in moment of inertia and perimeter, horizontal, big in flexural rigidity, in favor of distributing reinforcing steel bars, free from site contamination and soil squeezing effect, high in construction speed, high in project quality, convenient to apply and broad in prospects.

Description

Cast-in-place six or the immersed tube bored concrete hollow pile of octagon

Technical field

The utility model relates to the technology of pile foundation engineering structure, and particularly a kind of cast-in-place six or the immersed tube bored concrete hollow pile of octagon.

Background technology

1, in soft foundation is processed, a formula reinforcing body is set in the ground of being everlasting becomes composite foundation with original position ground local soil type, the Bearing Capacity of Composite Foundation characteristic value can be estimated by following formula:

$f_{\mathrm{spk}}=m\frac{R_a}{A_p}+\mathrm{\β}(1-m)f_{\mathrm{sk}}$

Bearing capacity of single pile R wherein _aRespectively by

⑴ the bearing capacity of single pile that the drag of, stake week and stake end soil provides

⑵, pile body axial compressive strength design load R _a≤ A _pf _cψ _cGet low value control.

Sand pile, broken stone pile belong to granular pile, lime pile, lime soil pile, cement mixing method, rotary churning pile and belong to flexible pile, the common weakness of these formula reinforcing bodies be strength of the mixing pile and elastic feel quantity all very low, under load action, the pile body decrement is large, bearing capacity of single pile is low, this type of flexible compound bearing capacity of foundation soil is subject to the very big restriction of strength of the mixing pile, replacement ratio is larger, invests higher.

Recently extensively adopt CFG stake, plain concrete pile, the rigid pile consolidated subsoils such as preformed pile, be referred to as rigid composite foundation, its strength of the mixing pile and modulus of elasticity are higher, shortcoming is that the circular cross-section girth is little, but pile side friction and end resistance that soft foundation provides are less, are subject to the very big restriction of the bearing capacity of single pile body that weak soil provides, and its strength of the mixing pile can not be not fully exerted.

2, in pile foundation engineering, bearing capacity of single pile R _aRespectively by:

⑴ the bearing capacity of single pile that the drag of, stake week and stake end soil provides

⑵, pile body axial compressive strength design load R _a≤ A _pf _cψ _cGet low value control.

Common pile body has bored pile, tube-sinking cast-in-situ pile, driving into type or Static Pressure Precast Piles, driving into type or static pressure precast hollow pile tube, the stake of cast-in-situ concrete major diameter cylinder etc.

Boring and tube-sinking cast-in-situ pile common feature are that section is solid, and the circular cross-section girth is little, and the pile such as bored pile adopts mud off often, and contaminated sites is serious, and a stake side exists mud skin, an end to have sediment.Generally far above stake week and a bearing capacity of single pile that the drag that end is native provides, second moment of area is little for the strength of the mixing pile design load, and arrangement of reinforcement is many, and its strength of the mixing pile and reinforced steel bar strength can not be not fully exerted.

The preformed pile of various different section shapes, precast hollow pile tubes etc. generally adopt centrifugal making, the prefabricated pile of stream curing method, and ductility is poor.Must adopt professed machine to take to squeeze into or the static pressure mode sinks to stake in the soil, construction noise is large, contaminated environment, cost are high.Because making and sinking apparatus is limit, the general section of pile body is less, and limited length often needs pile extension, and pile sinking quantity is more, and bearing capacity of single pile is not high.And have soil compaction effect, and often cause earth heaving, upfloat, the joint spoilage is large.These disadvantages are more outstanding at soft layer.

And the stake of cast-in-situ concrete major diameter cylinder exists unidimensional stake circular cross-section moment of inertia and girth little, and arrangement of reinforcement is many, and reinforced steel bar strength can not be not fully exerted.

3, the Row Piles Supporting Structure such as bored pile, cast-in-situ concrete thin-wall pipe pile in foundation pit supporting project, when calculating the horizontal distortion coefficient of stake, the molded breadth of stake is little, the horizontal bearing capacity of single pile that the drag of soil provides is little, circle and ring section moment of inertia, level and bending rigidity are little, be unfavorable for arrangement of reinforcement, its strength of the mixing pile and reinforced steel bar strength can not be not fully exerted.Bad lay and be connected member connect built-in fitting.

4, to be subjected to the pile-formation process restriction can only be the circular solids cross section in the large section stake such as bored pile, can't form other shape sections.The clamper that is attached on the hydraulic walking pile driver pile sinking leading truck generally can only clamping garden type member, can not other shapes of clamping, such as polygonal member, the inside and outside pile sinking sleeve pipe of clamping can only form round tubular cross section, can't form the hollow pile body of other shapes, can be fit to connect clamper and be connected the special-purpose assorted connection converter of garden type member in the urgent need to a kind of, in order to form the hollow pile body of other shape sections of large, the good arrangement of reinforcement of rigidity.Pile driving process China and foreign countries steel sleeve will be subject to larger soil pressure, the outer steel sleeve pipe of other shapes must be taked the measures such as ribbing, prevent that the distortion of outer steel sleeve pipe from causing the descending reinforcing cage difficulty, but after the ribbing, penetrating resistance strengthens, and behind the pile because of ribbing to the soil layer disturbance, affect soil layer to the performance of the side friction of stake.Six or octagon outer steel sleeve pipe have larger rigidity, not yielding, do not need external steel sleeve to take the measures such as ribbing.Sometimes, for obtaining larger rigidity and being convenient to join reinforcing bar and lay built-in fitting, need to make unequal-sided six or the hollow pile body of octagon.

For satisfying the demand of pile foundation engineering, composite foundation engineering, foundation pit supporting project design and construction, urgent need is opened up a kind of desirable pile body or desirable stake formula reinforcing body, the bearing capacity of single pile that the drag of its pile body axial compressive strength design load and and stake end soil native by stake week provides is more approaching, moment of inertia and Zhou Changda, be beneficial to arrangement of reinforcement and lay built-in fitting, section and the long restriction of stake are few, and easy construction, speed are fast, free from environmental pollution.Open up pile foundation engineering design and the new approach in rigid composite foundation field.

Summary of the invention

For the problem that exists in the above-mentioned technology, the purpose of this utility model provides a kind of cast-in-place six or the immersed tube bored concrete hollow pile of octagon, is beneficial to shorten the construction period of engineering, improves construction quality, and construction costs is saved in clean environment construction in place.

For achieving the above object, the technical solution adopted in the utility model provides a kind of this concrete hollow pile and includes pile body, pile cover, pile top, wherein: the cross sectional shape of described pile body is six or octagon, be provided with reinforcing cage in the pile body or do not establish reinforcing cage, precast reinforced concrete pile point together with the sealing pile cover that waters behind the described pile body top and pile body bottom, pile top is shaped as top and is provided with outer six or octagon internal circular hollow flange, the bottom is outer six or the ring-type cone of octagon internal circular hollow, form outer six or octagon in round hollow pile;

Six or the octagon hollow pile wall thickness that are provided with reinforcing cage are 〉=150mm; Six or the octagon hollow pile wall thickness of not establishing reinforcing cage are 〉=100mm.

Effect of the present utility model is that this can make stake week native substantially approaching with bearing capacity of single pile and pile body axial compressive strength design load that the drag of end soil provides, compare with unidimensional other types solid pile and garden type pile tube, the ratio of performance to price is good, moment of inertia and Zhou Changda, level and bending rigidity are large, be beneficial to arrangement of reinforcement, the horizontal bearing capacity of stake is high, and the single pile that the drag of soil is provided is vertical, horizontal bearing capacity and strength of the mixing pile and reinforced steel bar strength all are not fully exerted.Particularly more outstanding in dark, thick soft layer advantage.Shorten the construction period of the engineerings such as pile foundation, pattern foundation pit supporting structure, composite foundation, without contaminated sites and soil compaction effect, speed of application is fast, and workmanship is high, reduces engineering investment cost.Can be widely used in pile foundation engineering, composite foundation engineering, foundation pit supporting project design and construction, application makes things convenient for and has a extensive future.

Description of drawings

Fig. 1 is of the present utility model six or octagon hollow pile pile structural representation;

Fig. 2 is that the inside and outside steel sleeve of pile facility, supporting flange connect the converter structure schematic diagram;

Fig. 3 is positive hexagon hollow pile precast pile tip structural representation

Fig. 4 is positive octagon hollow pile precast pile tip structural representation;

Fig. 5 is the A-A sectional view of Fig. 3, Fig. 4;

Fig. 6 is the B-B sectional view of Fig. 3, Fig. 4;

Fig. 7 is the inside and outside steel sleeve structural representation of positive hexagon pile facility;

Fig. 8 is the inside and outside steel sleeve structural representation of positive octagon pile facility;

Fig. 9 is that the supporting flange of pile facility connects the converter structure schematic diagram;

Figure 10 is positive hexagon hollow pile section arrangement of reinforcement schematic diagram;

Figure 11 is positive octagon hollow pile section arrangement of reinforcement schematic diagram;

Figure 12 is inequilateral octagon hollow pile sectional schematic diagram;

Figure 13 is of the present utility model positive six or octagon hollow pile sectional schematic diagram;

Figure 14 is row of bored piles+cement mixing pile water seal curtain structural representation;

Figure 15 is positive hexagon hollow pile of the present utility model+high-pressure rotary-spray concrete stake waterproof structure schematic diagram.

Among the figure: 1, precast pile tip 2, six or octagon outer steel sleeve pipe 3, special-purpose assorted flange connects converter 4, inner circle steel sleeve 5, concrete blow tank 6, clamper 7, hydraulic pressure high-frequency vibratory hammer 8, mudhole 9, hollow cavity 10, earth inner core 11, cast-in-place outer six or octagon internal circular hollow pile body 12, top sealing pile cover 13, reinforcing cage 14, waist rail built-in fitting 15, pile cover gets rid of muscle 16, side pressure grouting pipe and valve 17, end madjack pipe and valve 18, bored pile 19, cement mixing pile 20, high-pressure rotary-spray concrete stake 21, flange bolt

The specific embodiment

Reach by reference to the accompanying drawings embodiment to of the present utility model cast-in-place six or the immersed tube bored concrete hollow pilework of octagon be illustrated.

Of the present utility model cast-in-place six or the immersed tube bored concrete hollow pile of octagon, this structure comprises cast-in-place outer six or octagon angle internal circular hollow pile body 11, be provided with reinforcing cage 13 in the pile body 11 or do not establish reinforcing cage, after being provided with, the top of pile body 11 waters sealing pile cover 12, the bottom of pile body is provided with precast pile tip 1, formation six or the immersed tube bored concrete hollow pile of octagon; The hollow pile wall thickness that is provided with reinforcing cage 13 is 〉=150mm; The hollow pile wall thickness of not establishing reinforcing cage is 〉=100mm.

Described precast pile tip 1 be shaped as outer six or the octagon internal circular hollow, the top of precast pile tip 1 is provided with flange, the bottom is provided with annular hollow inclination cone.

Described equilateral positive six or octagon hollow pile commonly used are with the high h mark of length of side a-, positive hexagon cross dimensions: 462-800～800-1500mm.Positive octagon cross dimensions: 331-800～621-1500mm.

Of the present utility model cast-in-place six or the job practices of the immersed tube bored concrete hollow pile of octagon may further comprise the steps: (hereinafter to be referred as cast-in-place six or the octagon hollow pile)

1) selection six or octagon hollow pile cross dimensions and stake are long

According to six or the load that need bear of octagon hollow pile; Geology clay distribution situation; Calculate the vertical and horizontal bearing capacity characteristic value that the soil body provides stake, such as stake week and a vertical bearing capacity of single pile characteristic value that the drag of end soil provides $R_a=u_p\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{q}_{\mathrm{si}}{l}_i+{\mathrm{\η}}_p{q}_p{A}_p;$

By the mud jacking technique soil body after technical code for building pile foundation (JGJ94-2008) grouting behind shaft or drift lining castinplace pile (5.3.10) the formula estimation employing vertical side frictional resistance and the end resistance that stake provides improved degree in case of necessity, press cement paste pressure and grouting amount that rear mud jacking technique is adopted in the estimation of technical code for building pile foundation (JGJ94-2008) castinplace pile grouting behind shaft or drift lining (6.7.4) formula; Adjust special-purpose machinery hydraulic walking pile driver by domestic HFA Series Hydraulic high-frequency vibratory hammer equipment pile setting capability factor; Selection six or octagon hollow pile overall dimensions and stake are long.

The 1.2 times of accounting cast-in-place six of vertical and horizontal bearing capacity that stake provided by the soil body or resistance to compression and the shear strength of octagon hollow pile are such as pile body compressive strength design load R _a≤ A _pf _cψ _c, select six or octagon hollow pile inner circle size, determine six or octagon hollow pile cross dimensions.

When being used for pile foundation, foundation pit supporting project, select to be provided with cast-in-place six or octagon hollow pile of reinforcing cage, and calculate the quantity of reinforcement of reinforcing cage.

When being used for rigid composite foundation, select not establish cast-in-place six or octagon hollow pile of reinforcing cage plain concrete.

2) outer six of precast concrete or octagon internal circular hollow precast pile tip.

3) preparation and six or the corresponding inner circle steel sleeve of octagon hollow pile, outer six or the octagonal bar steel sleeve pipe.

4) assembling reinforcement cage, the drag that pile foundation is provided such as the soil body than six or the compressive strength of octagon hollow pile little when more, need to carry out rear mud jacking when constructing to improve the drag that the soil body provides pile foundation, need madjack pipe and valve after reinforcing cage is laid.

When being used for foundation pit supporting project, need to lay waist rail built-in fitting 14 at reinforcing cage.

5) smooth location, rid, really fixed pile is laid precast pile tip 1.

6) with bolt with special-purpose assorted flange connect converter 3 be connected six or the upper end of octagonal bar steel sleeve pipe 2 connect, connect converter 3 and inner circle steel sleeve 4 with the special-purpose assorted flange of clamper 6 lockings that is attached on the hydraulic walking pile driver pile sinking leading truck; Mobile pile driver is proofreaied and correct stake position and a pile verticality to stake position, with the inner circle steel sleeve 4 of preparation, outer six or the lower end of octagonal bar steel sleeve pipe 2 block the precast pile tip 1 that places.

7) with the inner circle steel sleeve 4 that is attached to the preparation that the hydraulic walking pile driver will link to each other with described hollow pile top by the hydraulic pressure high-frequency vibratory hammer 7 on the pile sinking leading truck, outer six or octagonal bar steel sleeve pipe 2 vibration-sunks to design elevation, along with inner circle steel sleeve 4, outer six or the sinking of octagonal bar steel sleeve pipe 2 vibration, by be located at outer six or octagonal bar steel sleeve pipe 2 one sidewalls on mudhole 8, the earth of extruding is discharged.

8) open clamper 6 on the pile sinking leading truck and special-purpose assorted flange and connect converter 3 and outer six or the special-purpose assorted flange bolt in octagonal bar steel sleeve pipe upper end, inner circle steel sleeve 4, outer six or octagonal bar steel sleeve pipe 2 between hollow cavity in put into the good reinforcing cage of colligation, again special-purpose assorted flange is connected converter 3 be connected six or octagonal bar steel sleeve pipe 2 connect, relock special-purpose assorted flange connection converter 3 and inner circle steel sleeve 4 with the clamper 7 on the pile sinking leading truck.

As adopt six or the immersed tube bored plain concrete hollow pile of octagon, and can omit step 8), directly in described hollow cavity, fill plain concrete.

9) by being attached to outer six or the concrete receiving opening concrete perfusion on octagonal bar steel sleeve pipe 2 tops, pull out inner circle steel sleeve 4, six or eight type outer steel sleeve pipes 2 in the vibration of limit, the limit inner circle steel sleeve 4, outer six or octagonal bar steel sleeve pipe 2 between hollow cavity 9 interior concrete perfusion piles, six or the fullness coefficient of octagon hollow pile be 1.2-1.25; Removing is by the earth of extruding in the mudhole 8.

When 10) carrying out rear mud jacking construction such as needs, after 3-15 days, need by the madjack pipe on the reinforcing cage and valve, above-mentioned concrete pile of having constructed is carried out a side, pile bottom post grouting construction.

11) cut the loose concrete in reinforced concrete hollow stake top of having constructed, and excavate part earth in the molded hollow pile inner circle, at hollow pile upper pouring steel concrete top sealing pile cover 12, and the pile cover that reservation is connected with superstructure cushion cap or cap gets rid of muscle 15.

To six or octagon plain concrete hollow pile, cut hollow pile and push up loose concrete, and excavate part earth in the inner circle of hollow pile, at hollow pile upper pouring plain concrete top sealing pile cover 12.

Illustrate cast-in-place positive six or the premium properties used of the immersed tube bored concrete hollow pile of octagon by embodiment:

Embodiment 1: certain pile foundation engineering, and former employing φ 900mm bored pile, section is solid, garden type perimeter of section is little, section area A=6362cm2, perimeter L=2827mm, section factor W=71588cm3, moment of inertia I=3221451cm4.And the pile durations such as bored pile adopt mud off, the place mud contamination is serious, at the bottom of the stake side exists mud skin, hole behind the pile sediment is arranged, this project is in deep weak soil district, and girth is little, by all collateral resistances of soil layer stake and end resistance, the vertical ultimate bearing capacity of single pile that provides is far below pile body axial compressive strength design load, second moment of area is little, and arrangement of reinforcement is many, and its strength of the mixing pile and reinforced steel bar strength can not be not fully exerted.

Change that to adopt positive hexagon length of side a=577mm, h=1000mm, hollow interior garden be the immersed tube bored reinforced concrete hollow stake of φ 700mm, section area A=4801cm2, perimeter L=3462mm, section factor W=86379cm3, moment of inertia I=4817646cm4.Compare with φ 900mm bored pile: the section area ratio is 0.7546, and the girth ratio is 1.2246, and the moment of inertia ratio is 1.4954, and it is little to have a section area, moment of inertia and Zhou Changda, and level and bending rigidity are large, and cross sectional shape is beneficial to the advantage of arrangement of reinforcement.

By etc. rigidity replacement cross section calculate, it is about 25% to save concrete, by soil layer stake week collateral resistance and end resistance, the vertical ultimate bearing capacity of single pile that provides has improved 20%, the sectional reinforcement amount reduces.Ultimate bearing capacity of single pile and pile body axial compressive strength design load that the drag of stake week soil and stake end soil provides are substantially approaching, and the horizontal bearing capacity of stake is high, and the single pile that the drag of soil is provided is vertical, horizontal bearing capacity and strength of the mixing pile and reinforced steel bar strength all are not fully exerted.Construction period shortens, and workmanship improves, without contaminated sites.

Embodiment 2: certain foundation pit supporting project, the dark 12m of foundation ditch, groundwater table-1.0m, soil layer are divided into eight layers, are miscellaneous fill, silty clay, silt clay, clay, silt, silty clay, silt, powder fine sand.

The cement mixing pile water seal curtain of former employing φ 600 center to center distance 500, φ 1000mm row of bored piles soil-baffling structure, three road inner supports, grout pile center to center distance 1200mm is referring to Figure 14.Single pile section area A=7854cm2, perimeter L=3142mm, section factor W=98175cm3, moment of inertia I=4908739cm4, and bored pile piling duration employing mud off, the place mud contamination is serious, and complicated construction technique is long in time limit, and investment is high.Pattern foundation pit supporting structure single pile result of calculation is:

Maximum positive bending moment 996.5kN-m, maximum hogging moment 653.5kN-m;

Maximum positive shear 231.8kN, maximum negative shear-370.3kN, single pile arrangement of reinforcement 17 Φ 25;

Maximum displacement 30.3mm.

Change that to adopt positive hexagon length of side a=693mm, h=1200mm, hollow interior garden be the immersed tube bored reinforced concrete hollow stake of φ 900mm, minimum wall thickness (MINI W.) is 150mm, and pile center is apart from 1500mm, three road inner supports, adopt φ 600 high-pressure rotary jet grouting pile water proofs between the hollow pile gap, referring to Figure 15.Hollow pile section area A=6109cm2, perimeter L=4158mm, section factor W=136420cm3, moment of inertia I=7659929cm4.Compare with φ 1000mm bored pile: the section area ratio is 0.7778, and the girth ratio is 1.3233, and the moment of inertia ratio is 1.5604, and it is little to have a section area, moment of inertia and Zhou Changda, and level and bending rigidity are large, and cross sectional shape is beneficial to the advantage of arrangement of reinforcement.

The positive immersed tube bored reinforced concrete hollow stake of hexagon by etc. rigidity replacement cross section calculate, pattern foundation pit supporting structure single pile result of calculation is:

Maximum positive bending moment 1268.2kN-m, maximum hogging moment 832.2kN-m;

Maximum positive shear 292.3kN, maximum negative shear-465.5kN, single pile arrangement of reinforcement 10 Φ 25+10 Φ 22;

Maximum displacement 29.6mm.

Single pile is by all collateral resistances of soil layer stake and end resistance, the vertical ultimate bearing capacity of single pile that provides has improved 30%, can save concrete 22%, hollow pile pile center apart from 1500mm than Pile center to center distance 1200mm, increase 25%, can save concrete 22% * 1.25=27.5% altogether, amount to every meter calculating by foundation ditch length, can save reinforcing bar 16.4% altogether, can only between the positive immersed tube bored reinforced concrete hollow stake of hexagon, adopt rotary churning pile can satisfy the water proof requirement in addition, can save the cement mixing pile water seal curtain of former employing φ 600 center to center distance 500.

By this scheme foundation ditch displacement and pile concrete cross section and arrangement of reinforcement minimizing, construction period shortens, and workmanship improves, and the construction plant mud-less pollution is saved great amount of investment.

Embodiment 3: certain large-scale storage warehouse engineering, require the characteristic value of bearing capacity of foundation soil to reach 180kpa, but the place is in the deep weak soil of new filling district, though through inserting plastic draining board, vacuum preloading processing, the characteristic value of bearing capacity of foundation soil only reaches 80kpa, bearing capacity of foundation soil and sedimentation all can not be satisfied the requirement of storage warehouse, for this reason, carried out respectively cement mixing method, CFG stake, plain concrete pile, Prefabricated hollow pile, prefabricated tubular pile, cast-in-place plain concrete pile tube, positive octagon plain concrete hollow pile composite foundation scheme comparison:

Cement mixing method flexible compound ground scheme: its strength of the mixing pile and elastic feel quantity all very low, under load action, the pile body decrement is large, and bearing capacity of single pile is low, and Bearing Capacity of Composite Foundation is subject to the very big restriction of strength of the mixing pile, strength of the mixing pile was very low after the degree of depth surpassed 15m, and the pile difficulty.Replacement ratio is larger, invests highlyer, and speed of application is slow, and the construction plant is seriously polluted.

CFG stake, plain concrete pile rigid composite foundation scheme: its strength of the mixing pile and elastic feel quantity are higher, but round solid section girth is little, pile side friction and end resistance that soft foundation provides are less, strength of the mixing pile is subject to the low very big restriction of bearing capacity of single pile that weak soil provides much larger than all soil of stake and the native drag that stake is provided of stake end.Its strength of the mixing pile can not be not fully exerted.Replacement ratio is larger, invests highlyer, and speed of application is slow, and the construction plant is seriously polluted.

Prefabricated hollow pile, the rigid composite foundation schemes such as driving into type or static pressure precast hollow pile tube: the preformed pile of various different section shapes, precast hollow pile tube etc. must adopt professed machine to take to squeeze into or the static pressure mode sinks to stake in the soil.Because its section is less, limited length often needs pile extension, pile sinking quantity more.And have soil compaction effect, and often cause earth heaving, upfloat, joint damages.

Immersed tube bored plain concrete hollow pile composite foundation scheme: adopt positive octagon hollow pile length of side a=331mm, h=800mm, hollow interior garden is φ 600mm, minimum wall thickness (MINI W.) 100mm, outer perimeter is 2648mm, section area 2472cm2, pile center's distance is 2800mm, the bearing capacity of single pile that all soil of stake and the native drag of stake end provide is equivalent to the 800mm stake, but the stake section area only is 49.2% of 800mm stake, vertical bearing capacity of single pile and strength of the mixing pile that native drag is provided all are not fully exerted, invest less, short construction period, workmanship is high, the construction plant mud-less pollution.

Compare with φ 800mm wall thickness 100mm pile tube, although section area increases to some extent, the native area replacement ratio m of stake has improved 5.5%, and the bearing capacity of single pile that all soil of stake and the native drag of stake end provide has improved 6.4%, and the Bearing Capacity of Composite Foundation characteristic value has improved 8.1%.Ground stabilization is effective.

The scope of application of the utility model cast-in-place six or the immersed tube bored concrete hollow pile of octagon:

Six or the immersed tube bored plain concrete hollow pile of octagon wall thickness be 〉=100mm to be mainly used in the rigid composite foundation engineering; Immersed tube bored steel concrete six or octagon hollow pile wall thickness are 〉=150mm to be mainly used in pile foundation, foundation pit supporting project; Because device height is limit, general stake is long should not to surpass 30m.

The utility model is not suitable for the engineering design and construction of pile foundation engineering with hard soil layer, rigid composite foundation, foundation pit supporting project.

Of the present utility model cast-in-place six or the immersed tube bored concrete hollow pile of octagon adopt special-purpose pile sinking machinery to be hydraulic walking pile driver, domestic HFA Series Hydraulic high-frequency vibratory hammer and clamper.

Cast-in-place six or the immersed tube bored concrete hollow pile pore-forming of octagon facility structure as shown in Figure 1, 2; Hexagon precast pile tip structure as shown in Figure 3; Octagon precast pile tip structure as shown in Figure 4; Precast pile tip section such as Fig. 5, shown in Figure 6; The supporting inside and outside steel sleeve cross-sectional configuration of hexagon as shown in Figure 7; The supporting inside and outside steel sleeve cross-sectional configuration of octagon is shown in 8; Supporting flange connects converter structure as shown in Figure 9; The positive immersed tube bored reinforced concrete hollow stake of hexagon section arrangement of reinforcement as shown in figure 10; The positive immersed tube bored reinforced concrete hollow stake of octagon section arrangement of reinforcement as shown in figure 11.Inequilateral octagon hollow pile section, as shown in figure 12, a, b represent respectively the inequilateral length of side among the figure.Cast-in-place six or the immersed tube bored concrete hollow pile of octagon as shown in figure 13.Figure 14 is row of bored piles+cement mixing pile water seal curtain structural representation, and Figure 15 is positive hexagon hollow pile of the present utility model+high-pressure rotary-spray concrete stake waterproof structure schematic diagram.Side pressure grouting pipe and valve 16, end madjack pipe and valve 17, bored pile 18, cement mixing pile 19, high-pressure rotary-spray concrete stake 20, flange bolt 21 are arranged among the figure.

The quality measures main points of the utility model cast-in-place six or the immersed tube bored concrete hollow pile of octagon:

Size and the intensity of strict control precast pile tip;

During the control immersed tube, the verticality of internal and external casing;

Control six or the concrete slump of the immersed tube bored concrete hollow pile of octagon;

The pipe-pulling speed of strict control internal and external casing.

Claims (1)

1. one kind cast-in-place six or the immersed tube bored concrete hollow pile of octagon, this concrete hollow pile includes pile body, pile cover, pile top, it is characterized in that: the cross sectional shape of described pile body is six or octagon, be provided with reinforcing cage in the pile body or do not establish reinforcing cage, together with the precast reinforced concrete pile point that waters pile cover and pile body bottom after the sealing of described pile body top, pile top is shaped as top and is provided with outer six or octagon internal circular hollow flange, the bottom is outer six or the ring-type cone of octagon internal circular hollow, form outer six or octagon in round hollow pile;

Six or the octagon hollow pile wall thickness that are provided with reinforcing cage are 〉=150mm; Six or the octagon hollow pile wall thickness of not establishing reinforcing cage are 〉=100mm.

Images