A kind of drilled pile platform construction method on the precipitous naked rock of deep water torrent intectate
Technical field
The invention belongs to field of bridge construction, be specifically related to a kind of drilled pile platform construction method on the precipitous naked rock of deep water torrent intectate.
Background technology
Along with socioeconomic development, demand for convenient traffic is further strong, it is also more and more to be built in various geologic bridge engineering, deep-water bridge bored pile foundation work platform for boring is the temporary construction facility that must build, can be assembled into the floating water upper mounting plate with the buoyancy tank ship, but need the facilities such as a large amount of line anchors, station keeping ship; Also can utilize stake behind the steel cofferdam elder generation weir, steel inclosure or the double formula job platform that fixes of steel box.What generally adopt in recent years, is that steel pipe pile, shaped steel, Bailey truss or universal rod body are assembled into fixed job platform.
Bridge in the past generally all is built on the rivers and lake that have than thick-covering, under this geological conditions, the boring pile construction is general to adopt traditional " halieutics " to carry out, be about to the steel casing in place after, by pile hammer inserted to play steel casing to the covering layer design elevation.But, it is inclined uncovered rock face and shallow overburden inclination scar that a lot of rivers, lake and Marine Geology situation are arranged, the mouth spillage is processed at the bottom of the difficult point of drilled pile construction under this kind geological conditions is the location and installation of steel casing and casing, as adopt conventional method to construct, because the role and influence of current, stormy waves and wind load, the stability of steel casing pile foundation can't be guaranteed, thereby affects the security performance of steel casing and the construction speed of major project.
For the geological condition of the precipitous naked rock of above-mentioned intectate, prior art often adopts underwater demolition, artificial covering layer, jacket, scar preexisting hole to be embedded into the schemes such as steel pipe.
Underwater demolition: Wuhan-Guangzhou passenger-dedicated line emphasis Bridge Project, the depth of water 18m of place, pier position in the water, naked scar is inclined to 35 °, adopt the drilling platform scheme, at first with the scar explosion leveling of tilting, arrange the steel casing, the throwing sandbag is buried casing underground on the riverbed again, rely on the existing stake of nearly Dun Chu to come stabilized platform, thereby form the drilled pile platform.This scheme needs underwater demolition, and the scarfing cinder workload is large, and the cycle is large, and cost is high, and needs existing stake to keep the stable of platform.
Artificial covering layer: certain Bridge Project on the Liujiang of Liuzhou, the depth of water 15m of place, pier position in the water, naked scar is inclined to 15 °, adopts the drilling platform scheme, first at the thick earth bag of the pier position throwing 3m of place, again inserted to play steel pipe pile.Artificial covering layer scheme needs a large amount of earth bags of throwing in flat roof area, and engineering quantity is large, and construction cost is high.
Jacket: the nearly island of Shanghai Bridge at Sea section engineering, the bridge location sea bed is shallow overburden and naked rock, adopting the jacket trestle is the subaqueous work passage, adopt jacket platform as the drilling platform of main pier in the water, the steel pipe with many diameter 1.1m during construction is linked to be jacket by land, and shipping is located to the pier position again, hang ship with large 1500t and hang installation, this scheme needs large-tonnage to hang ship and workboat, and steel using amount is large, and construction period is longer.
The scar preexisting hole is embedded into steel pipe: the pier in water depth of water 26m of Zhejiang bridge, the riverbed intectate, scar is 45 ° of inclinations, trestle, platform construction adopt preexisting hole to be embedded into the fixing constructure scheme of steel casing, namely use the percussive drill preexisting hole greater than the pile tube diameter in the trestle steel pipe pile position, pour into a mould underwater concrete after putting into steel pipe pile outside the pile tube of preexisting hole, it directly is stabilized in the rock stratum, the steel casing also adopts similar approach to arrange.This scheme construction period is longer, needs operation on floating platform, and water level needs more stable, and flow velocity is little.
The shortcomings such as in sum, above scheme exists all that workload is large, long construction period, cost are large.
Therefore those skilled in the art is badly in need of a kind of scheme that can effectively solve drilling platform construction on precipitous hard naked rock river bed, can reach low, the purpose safely and efficiently of short construction period, cost simultaneously.
Summary of the invention
The objective of the invention is according to above-mentioned the deficiencies in the prior art part, a kind of drilled pile platform construction method on the precipitous naked rock of deep water torrent intectate is provided, this job practices cuts into the shape that is complementary with precipitous naked scar with mouth at the bottom of described steel casing and the steel pipe pile on the coast in advance by the underwater bathy metry technology, steel pipe pile and the anchoring of precipitous naked scar slip casting embedding rock with the framework type platform, solve the anchoring of steel pipe pile on precipitous hard naked rock to reach, the Against Sliding Stability problem, simultaneously in steel casing bottom, build underwater concrete between steel casing and the steel enclosure, form the underwater cofferdam of steel casing, so that described steel casing is stable on the precipitous naked scar convenient follow-up bored pile construction.
The object of the invention realizes being finished by following technical scheme:
A kind of drilled pile platform construction method on the precipitous naked rock of deep water torrent intectate, be specifically related to precipitous naked scar and and be arranged at the trestle of described drilled pile platform upstream side, it is characterized in that comprising the steps: at least to set up some leading trucks in the downstream of described trestle, be used for the spacing of some steel pipe piles upper end, described steel pipe pile lower end is fixedly supported on the described precipitous naked scar; Begin to set up the framework type platform at described steel pipe pile, and sequentially continue described leading truck to be set, steel pipe pile is set according to described framework type platform extension direction, and extension is set up until finish the integral erection of described framework type platform;
Be fixedly installed the leading truck of described drilled pile steel casing at described framework type platform, be used for the spacing of described steel casing upper end; Determine the installation position of described steel casing lower end on described precipitous naked scar, and measure its position form parameter; Select the steel casing, and make end mouth-shaped parameter and the described installation bit position form parameter coupling of steel casing installation end; Weld a steel enclosure at described steel casing installation end by shape steel bracket; The described steel casing of sedimentation and steel enclosure thereof are in described installation position, and its after-pouring underwater concrete so that described underwater concrete is filled full described steel casing bottom and the steel enclosure is inner, is finished follow-up drilled pile construction afterwards.
The fixed support of described steel pipe pile lower end is at first to determine the installation position of steel pipe pile on described precipitous naked scar, and measures its position form parameter; Select steel pipe pile, and make end mouth-shaped parameter and the described installation bit position form parameter coupling of steel pipe pile installation end.
The waters is provided with soundd navigation and ranging around described steel pipe pile and the steel casing.
The fixed support step of described steel pipe pile lower end also comprises: the described steel pipe pile of sedimentation is in described installation position, and in its periphery underwater cofferdam is set, in described steel pipe pile, build afterwards the underwater concrete layer, with described steel pipe pile installation end and described underwater cofferdam and described precipitous naked scar and underwater concrete is laminated is integrated, after described underwater concrete layer reaches construction reference, along described steel pipe pile central axis to drilling anchor hole; Described anchor hole runs through described underwater concrete layer and stretches in the inside basement rock of described precipitous naked scar, at last skyhook and slip casting anchoring in described anchor hole.
In described anchor pole binding madjack pipe is arranged, by a pneumatic mortar machine from described madjack pipe to described anchor hole bottom compressed water slurry, described cement paste is depressed into that the layer of concrete end face gets final product under the described steel pipe pile bottom water, so that described anchor pole is integrated with inside basement rock and the steel pipe pile anchoring of described precipitous naked scar.
The underwater concrete layer height of described steel pipe pile bottom is not less than described anchor pole and enters the rock degree of depth, and the length of described anchor pole more than precipitous naked scar must not enter rock length less than it.
Described framework type platform connects as one by shaped steel and existing fender pile.
Described steel casing is transferred to described precipitous naked scar in order to spacing by described leading truck, described leading truck is double-deck leading truck, be provided with the correction jack at described leading truck, when being checked through described steel casing plan-position and verticality and having deviation, regulates by described correction jack soundd navigation and ranging, until described steel casing center and the centrical deviation of design and installation are not more than 80mm.
Described steel enclosure diameter is greater than described steel casing diameter 1m~3m.
Advantage of the present invention is, (1) adopt undersea detection technology and by the location parameter surveyed on the coast at the bottom of the precut steel pipe pile at the bottom of mouth and the steel casing mouth its and precipitous naked scar are complementary, safe and efficient, reduce the deep diving workload, the reduction construction risk; (2) steel pipe pile in order to support platform is connected the slip casting embedding rock anchors technology that adopts in the framework type platform structure with precipitous naked scar, rely on the bond stress of underwater concrete slurry and anchor pole, stake base concrete and riverbed basement rock, so that steel pipe pile firmly is anchored on the precipitous naked scar, short construction period, cost are low, safe and efficient; (3) steel cofferdam that is made of steel enclosure and underwater concrete of steel casing bottom has solved that mouth at the bottom of the drilled pile steel casing is fixed and the technical barrier of spillage when holing, simultaneously steel casing inner concrete levelling precipitous naked scar, inclined-plane perforate when being convenient to creep into.
Description of drawings
Fig. 1 is framework type platform construction process chart among the present invention;
Fig. 2 is Construction technology of bored pile flow chart among the present invention;
Fig. 3 is the steel pipe pile floor map of setting up the framework type platform among the present invention by leading truck;
Fig. 4 is that steel pipe pile falls to schematic diagram on the precipitous naked scar among the present invention;
Fig. 5 builds the underwater concrete schematic diagram in steel pipe pile among the present invention;
Fig. 6 is the anchor hole schematic diagram that extends into the inner basement rock of precipitous naked scar among the present invention in steel pipe pile;
Fig. 7 is the schematic diagram that carries out slip casting embedding rock anchors technology among the present invention in steel pipe pile;
Fig. 8 is the overall schematic of steel pipe pile bottom anchor structure among the present invention;
Fig. 9 is framework type platform facade arrangement diagram among the present invention;
Figure 10 is framework type platform plane arrangement diagram among the present invention;
Figure 11 is that the correction jack on the leading truck is arranged schematic diagram among the present invention;
Figure 12 is the underwater cofferdam schematic diagram of steel casing bottom among the present invention;
Figure 13 is that the drilled pile steel casing on the framework type platform is arranged schematic diagram among the present invention.
The specific embodiment
Feature of the present invention and other correlated characteristic are described in further detail by embodiment below in conjunction with accompanying drawing, so that technician's of the same trade understanding:
Such as Fig. 1-13, mark 1-24 is respectively among the figure: connection structure 14, upstream side fender pile 15, downstream fender pile 16, middle of the river side fender pile 17, leading truck 18, correction jack 19, steel casing 20, steel enclosure 21, dry-mix concrete bag 22, underwater concrete layer 23, main pier 24 between leading truck 1, steel pipe pile 2, trestle 3, precipitous naked scar 4, underwater concrete layer 5, dry-mix concrete bag 6, anchor hole 7, madjack pipe 8, geological drilling rig 9, anchor pole 10, cement paste 11, framework type platform table top 12, framework type platform 13, stake.
Embodiment: present embodiment is specifically related to a kind of drilled pile platform construction method on the precipitous naked rock of deep water torrent intectate.Present embodiment is that example is elaborated in connection with Qianjiang grand bridge engineering, and engineering is positioned at Qianjiang, Guangxi, and river deep water is anxious, and both sides, river bank slope hypsography is large, and the bank slope part sees that basement rock exposes, and it is not wait between 25 °~60 ° that the riverbed scar tilts; Its main bridge is that 106+200+106m three strides the prestressed concrete continuous rigid frame, 3#, 4# pier are main piers in the water of continuous rigid frame, two pier structures are identical, cushion cap is the spindle profile, every mop is put 3 rows totally 15 φ 2.5m embedding rock drilled piles, pile foundation requires the complete middle Baiyun rock mantle of embed wholly (frk=80MPa) to be not less than 10m, adopts C40 concrete under water.
Drilled pile platform in the present embodiment specifically comprises framework type platform and drilled pile steel casing, adopts slip casting embedding rock anchors technology to set up the framework type drilling platform; As operation and the anchoring pile when crossing flood, solved the stable problem of framework type platform in rapid deep water river with permanent fender pile; Use the undersea detection technology and successfully lay the Large-diameter Steel casing; Mouth was fixed the technical barrier that reaches spillage when holing at the bottom of application underwater cofferdam technology had solved drilled pile steel casing; Guaranteed that deep water large diameter borehole pile driving construction finishes smoothly.
Shown in Fig. 1-13, below be the concrete steps of the drilled pile platform construction on the precipitous naked rock of deep water torrent intectate:
(1) at first at the downstream of trestle 3 side double-deck leading truck 1 is set, use depth-sounder to record the discrepancy in elevation of the precipitous naked scar 4 in steel pipe pile 2 implantation places all around along leading truck 1, the discrepancy in elevation according to the precipitous naked scar 4 that records, the spreading steel pipe pile 2 on the coast, simultaneously the end mouth of steel pipe pile 2 is cut into and precipitous naked scar 4 shape that is complementary, carry out bearing mark, avoid deflecting after steel pipe pile 2 entry, the stake end and precipitous naked scar 4 are misfitted; Install at precipitous naked scar 4 simultaneously and set up a soundd navigation and ranging, this soundd navigation and ranging can show the mode with image of scar situation under water, the concrete engineering of building that is used for the installing of follow-up steel pipe pile 2, underwater concrete layer 5 under water, check the implantation situation of steel pipe pile 2 and the situation of building of underwater concrete layer 5, replaced diver's operation.
(2) crane is temporarily fixed on steel pipe pile 2 tops on the leading truck 1 behind steel pipe pile 2 implantations by leading truck 1 whole long lifting first row positioning supports steel pipe pile 2, and connection structure 14 formation integral body between stake are set between first row steel pipe pile 2 tops; Second row steel pipe pile 2 is installed afterwards or is respectively arranged later on steel pipe pile 2, steel pipe pile 2 and leading truck 1 is temporary fixed after, weld rapidly connection structure 14 between the stake between adjacent two row's steel pipe piles 2, the local stabilising system that forms.
(3) send diver's entry along the mouth outside, the end pile one circle dry-mix concrete bag 6 of steel pipe pile 2; Adopt vertical conduit method C30 concrete under steel pipe pile 6 interior priming petocks, along with concrete in steel pipe pile 2 interior risings, concrete is under the inside and outside differential pressure effect, outwards flow out in slit between steel pipe pile 2 and precipitous naked scar 4, be filled between the dry-mix concrete bag 6, form a underwater cofferdam, simultaneously at the end of steel pipe pile 6 interruption-forming underwater concrete layer 5, the height of underwater concrete layer 5 is not less than the thereafter degree of depth of anchor pole 10 embedding rocks; During pouring underwater concrete, can utilize underwater detectoscope that the inside and outside concreting situations of steel pipe pile 2 are monitored, abnormal conditions appear or build finish after, in time arrange the diver to stake at the bottom of situation confirm to check.
(4) after steel pipe pile 2 interior underwater concrete layer 5 placing intensity reach 70%, framework type platform table top 12 is installed.Geological drilling rig 9 moves to leading truck 1 place afterwards, in steel pipe pile 2 internal drillings; The drill bit of geological drilling rig 1 is after passing through the underwater concrete layer 5 of steel pipe pile 2 bottoms, and at a slow speed drilling well prevents the drill bit sideslip; After drill bit enters competent bed 50cm, can pass through counterweight, strengthen the pressure of the drill, accelerate rate of penetration; When entering basement rock, answer core taking inspection, confirm starting point and the degree of depth of rock stratum face, in the pore forming process, when joint fissure is intensive, broken serious when the rock stratum, should take first pressure injection high-strength cement slurry to make rock mass fixed, redrilling after slurry reaches some strength is until anchor hole 7 is to design elevation.
(5) at anchor pole 10 binding pressure-resistant plastic madjack pipes 8, the drilling rod by geological drilling rig 9 is seated to anchor pole 10 in the anchor hole 7, removes subsequently the drilling rod of described geological drilling rig 9.To anchor hole 7 interior compressed water slurries 11, when mud jacking began, the system of mixing had also been laid in cement paste 11, guaranteed the continuity of mud jacking process, after cement paste 11 stirs, with pneumatic mortar machine from plastics madjack pipe 8 to anchor hole 7 bottom mud jacking.Be the seepage that satisfies borehole anchorage section crevice water mud 11 and the water enchroachment (invasion) that prevents top water mud, the size of groundwater increment is determined by field experiment.Utilize underwater detectoscope to observe the mud jacking situation in the mud jacking process, underwater concrete layer 5 end face that cement paste 11 is depressed in the steel pipe pile 2 get final product.Carry out anchor pole 10 resistance to plucking static loading tests thereafter.When steel pipe pile 2 bottom water mud 11 anchoring body compressive strength reach 70%, remove leading truck 1.
(6) by above-mentioned steps 1.-5., all steel pipe piles 2 are carried out slip casting embedding rock anchoring construction, finish setting up of whole framework type platform 13.Wherein after framework type platform 13 is set up half or sufficient space is arranged, carry out fender pile construction, framework type platform 13 is connected with the existing upstream side fender pile 15 that is arranged on framework type platform 13, downstream fender pile 16 and middle of the river side fender pile 17 respectively by shaped steel.
(7) at framework type platform 13 double-deck leading truck 18 is set, first floor is arranged on the end face of framework type platform 13, the second layer is arranged on the bottom surface of framework type platform 13, be respectively arranged with correction jack 19 at four angles of leading truck 18 in order to regulate the position of steel casing 20, wherein leading truck 18 be positioned at steel casing 20 the installation position, riverbed directly over.
(8) before steel casing 20 is installed, probe and the wire of depth-sounder are fixed on the Metallic rod, its probe is located at underwater 30cm, the discrepancy in elevation along the precipitous naked scar 4 of mounted leading truck 18 eight equal parts point measurements, can determine length and the end mouth discrepancy in elevation thereof of steel casing 20 on the coast the end mouth of steel casing 20 to be cut into the shape that is complementary with precipitous naked scar 4 according to this end mouth discrepancy in elevation according to the each point depth of water that records; Install at precipitous naked scar 4 simultaneously and set up a soundd navigation and ranging, this soundd navigation and ranging can show the mode with image of scar situation under water, the concrete engineering of building that is used for the installing of follow-up steel casing 20, underwater concrete 23 under water, the implantation situation and the underwater concrete 23 that check steel casing 20 are built situation, have replaced diver's operation.
Steel casing 20 is installed when (9) selecting water flow stationary, crane is installed coxopodite steel casing 20 by leading truck 18, transfers to the water surface, and small-sized cargo ship loads steel enclosure 21 to the end mouth of steel casing 20, the weld type steel bracket is fixed on steel enclosure 21 in the end mouth of steel casing 20; Crane continues to transfer steel casing 20, and coxopodite steel casing 20 is fixed on framework type platform 13 end faces, and spreading steel casing 20 repeats above-mentioned steps, until steel casing 20, steel enclosure 21 implantations; Wherein said steel enclosure 21 is rolled by steel plate and forms, it also cuts into its end mouth the shape that is complementary with precipitous naked scar 4 on the coast according to the measured data of underwater bathy metry instrument, its radius is less than 1/2 drilled pile centre distance, radius 0.5~1.5m greater than steel casing 20, according to the tilt condition of precipitous naked scar 4, minimum constructive height is not less than 80cm.
(10) check steel casing 20 plan-positions, verticality, if deviation is arranged regulates by the correction jack 19 of the diagonal angle on the leading truck 18, be not more than 80mm until satisfy center and the drilled pile central plane position deviation of steel casing 20, steel casing 20 is not more than 1% in the gradient of vertical direction.Utilize underwater detectoscope to check the implantation situation of steel casing 20, steel enclosure 21; Send afterwards the diver to utilize the 22 shutoff steel enclosures 21 of dry-mix concrete bag and precipitous or the slit between the precipitous naked scar 4 of tilting.
(11) by the vertical conduit method build between steel enclosure 21 and the steel casing 20, C30 concrete 5 under water in the steel casing 1, utilize under water underwater detectoscope to observe the concreting situation in concrete 5 casting process; When the top of pouring into to steel enclosure 2, stop, continuing thereafter perfusion steel casing 1 interior underwater concrete 5, in drilling process, resist precipitous naked scar 4.Carry out at last the drill-pouring pile construction, so far, finish the construction of drilled pile platform.
This job practices compared with prior art can be classified as following characteristics:
1. slip casting embedding rock anchors technology: after steel pipe pile 2 is installed on the precipitous naked scar 4, slit between sealing steel pipe pile 2 end mouth and the precipitous naked scar 4, in steel pipe pile 2, build underwater concrete, utilize geological drilling rig 9 at steel pipe pile 2 interior brill anchor holes 7, stretch into precipitous naked scar 4 inner basement rock, skyhook 10 grouting behind shaft or drift lining anchorings.Rely on the bond stress of cement slurry 11 and anchor pole 10, stake end underwater concrete layer 5, riverbed basement rock, solve anchoring, the antiskid of steel pipe pile 2 on precipitous hard naked rock and move stable problem.
2. anchoring pile: set up rapidly trestle 3, framework type platform 13 in dry season, at the platform upstream side 2 permanent fender pile of constructing in advance, fender pile is connected with framework type platform 13, solve the stable problem of framework type platform 13 in rapid deep water river, guarantee operation and cross the flood construction safety.
3. undersea detection technology: with depth-sounder under water measure steel casing 20 the Yan Chu riverbed discrepancy in elevation, framework type platform 13 in advance 20 end of cutting of steel casing mouth replace the deep diving cutting, make behind 20 end of the steel casing mouth implantation with precipitous or the precipitous naked scar 4 that tilts is substantially identical; In 20 installations of steel casing, underwater cofferdam work progress, replace the deep diving inspection with underwater detectoscope remote control inspection.
4. underwater cofferdam technology: when steel casing 20 is installed, mouth is installed steel enclosure 21 at the bottom of the coxopodite casing, steel enclosure 21 is the same with steel casing 20, cut according to the discrepancy in elevation at the bottom of the riverbed in advance, together be in place with steel casing 20, form underwater cofferdam, again in the cofferdam, 20 end of steel casing mouth builds underwater concrete with anchoring steel casing 20, solve the technical barrier of spillage when drilled pile steel casing 20 end mouth is fixing to reach boring, simultaneously casing inner concrete levelling precipitous naked scar 4, inclined-plane perforate when being convenient to creep into.