A kind of sheltered reverse excavation subway station steel pipe column accurate positioning method
Technical field
The invention belongs to building structure construction field, be specifically related to the positioning construction method of subway station steel pipe column.
Background technology
Steel pipe column, with the performance of its excellence, is widely used in the subway station engineering of digging method construction.Steel pipe column construction location is as one of heavy difficult point in sheltered reverse excavation station construction, and its construction surface is narrow, and environment is poor, and positioning accuracy request is high.The location of steel pipe column, end opening adopts steady arm to locate usually, localization method suitable for reading mainly contains: (1) flower basket bolt is located, the interim hook of welding on the steel bushing of steel pipe column top and corresponding absolute altitude, be connected suitable for reading for steel pipe column with steel bushing with 3 ~ 4 steam boat ratchets, located by adjustment flower basket bolt length.(2) shaped steel well cabinet frame is fixed, and shaped steel welds micro actuator adjustment location.(3) between and dado structure suitable for reading at steel pipe column, 4 little lifting jack are installed, by lifting jack, adjustment steel pipe column center suitable for reading.(4) adopt the leading screw symmetry location after four improvement, leading screw band card one end is supported on the ring flange of steel pipe column top, and band holder one end is supported on dado structure.
Summary of the invention
The object of the invention is: realize the high-precision setting-out requirement of steady arm, guarantee the accurately in place of steel pipe column elevation.
To achieve these goals, technical scheme of the present invention is to provide a kind of sheltered reverse excavation subway station steel pipe column accurate positioning method, comprise the following steps: (1), steel pipe column pile foundation location survey, (2), rig squareness measurement, (3), the location survey of steel pipe column steady arm, (4) erection of steel pipe column location, wherein (3) step specifically comprises: steady arm elevation location, steady arm plane positioning; (4) step specifically comprises: steel pipe column is vertically located, steel pipe column elevation is checked.
Concrete steps are:
(1), steel pipe column pile foundation location survey
Absolute altitude at the bottom of the design plane coordinate at the steel pipe column pile foundation center calculated with drawing and stake, the on-the-spot planimetric position adopting total powerstation-pole coordinates lofting mode to release central pile center, and involve 2 orthogonal lead-in wires by pile center's point, carry out and draw stake, so that often check a heart position in piling construction process;
(2), rig squareness measurement
O place erection total powerstation at an arbitrary position, until drilling rod unsettled static after, total powerstation is under non-prism NP pattern, measure the horizontal range D of instrument to drilling rod center, then bottom survey record drilling rod and the horizontal direction value of top ad-hoc location and zenith distance, thus calculate the projected length of drilling rod at level and vertical direction, and according to the verticality computing formula of the rig derived
, calculate rig verticality, if verticality is partially within the scope of permissible value, then piling of can constructing;
(3), the location survey of steel pipe column steady arm
The while that what steel pipe column adopted being upper and lower two ends, localization method is fixed, and pipe column lower end location depends on autonavigator, flower basket bolt fine setting location, upper end;
(3.1) steady arm elevation location
The elevation location of steady arm adopts and hangs steel ruler laying off, and on the ground, steel tape is just being hung on the position near steel pile casting wall, and spirit-leveling instrument is erected at leveling point A and steel pile casting relative intermediate position, to reduce i angle error.Backsight reads the reading a of levelling pole, and forward sight reads the ground reading R of steel ruler
on, consider the factors such as the long correction of the chi of steel ruler and temperature correction, the following formula A of computing formula:
(formula A)
After hanging up properly steel ruler at every turn, set up No. 2 spirit-leveling instruments respectively, read on a and R, under calculating R, if the difference under the R calculated for twice is within ± 2mm, then average, then under steel ruler reading R, mark a horizontal line by the survey work of down-hole with surveyor's staff on steel pile casting inwall, we are according to actual conditions here, steel ruler is hung up properly respectively corresponding 4 of steel pile casting tube wall cross axis direction, steel pile casting inwall does horizontal lines mark, mutually to check, controls steady arm installed height mark;
(3.2) steady arm plane positioning
Steady arm plane positioning adopts the downward cultellation method of laser, and concrete cultellation process is as follows:
1) steel plate workbench is placed on steel pile casting place suitable for reading, adopts total powerstation polar method, by the setting-out of the planar central of steady arm point within the scope of the batten on steel plate workbench, and carry out mark;
2) with gauge point on batten for alignment, steel plate workbench sets up wooden tripod and prism, and then adopt naturalization laying off, accurate setting-out goes out a design coordinate of heart point P;
3) prism is removed from pedestal, then laser plummet is placed on pedestal, batten on steel plate workbench is removed, central point is just thrown in down-hole by the cultellation reserved opening on steel plate by laser plummet, for avoiding plumb aligner cultellation visor not vertical error, three directions are changed during each cultellation, if when point position all falls within same point, be namely a heart, otherwise three direction point A, B, C can be produced and form a triangle, now, getting leg-of-mutton circumscribed circle centre point O, is namely a heart, finally, be welded and fixed steady arm, casting concrete;
(4) erection of steel pipe column location
After device concrete to be positioned reaches design strength, carry out the lifting of steel pipe column, bottom steel pipe column, directly embed steady arm, or bottom it, be welded with spacer ferrule embedding steady arm, its pipe end is firmly seated on steady arm cross location-plate, by the bottom of absolute altitude measuring column with the degree of agreement of steady arm;
(4.1) steel pipe column is vertically located
Locate owing to adopting steady arm bottom steel pipe column, top adopts flower basket bolt fine setting, for ensureing the verticality of steel pipe column, only need adopt method shown in (1) step, field lofting goes out steel pipe column center point, and sets up laser plummet on the point of center, open laser target to, make steel pipe column upper and lower center point in same laser beam by adjustment flower basket bolt, then determine steel pipe column and vertically locate errorless;
(4.2) steel pipe column elevation is checked
Adopt the top mark hanging steel ruler method measurement steel pipe column high, compare with design load, check the degree of agreement with steady arm at the bottom of post;
During measurement, spirit-leveling instrument is erected at leveling point A and steel pile casting relative intermediate position, and to reduce i angle error, the reading a of backsight levelling pole and the upper chi reading R of steel tape measured by spirit-leveling instrument
on, then read the lower chi reading R corresponding with steel pipe column top planes align place
under.If consider the factors such as the long correction of the chi of steel ruler and temperature correction, steel pipe column top absolute altitude computing formula is as follows:
(formula B)
Its construction way is: by total station survey, the drilling rod verticality correcting rig, guarantee the construction quality in pile hole construction pile hole; Utilize elevation survey method, ground elevation is delivered to down-hole, control the design height of steady arm bottom steel pipe column; Then with total powerstation and laser plummet associating setting-out cultellation location, orient the planar central point of steady arm in down-hole, casting concrete fixed locator, reach after design strength until concrete, hang steel pipe column, again go out steel pipe column top planes central point with total powerstation and laser plummet associating setting-out cultellation, two fixing with gaily decorated basket spiral shell, build rim of a cup concrete and steel pipe column inner concrete successively, complete the construction at steel pipe column position.
This method adopts the non-prism electronic total station associating high-precision laser plumb aligner of measuring technique advanced person, analyzed by measuring error transmission, and take the technical measures such as normalization method, solve the problems such as steel pipe column construction location and perpendicularity correction locating tab assembly reliably, and in metro station steel pipe column work progress, obtain successful Application, for similar engineering provides referential engineering survey experience.
Accompanying drawing explanation
Fig. 1 is central pile centralized positioning schematic diagram;
Fig. 2 is steady arm schematic side view;
Fig. 3 is steady arm schematic top plan view;
Fig. 4 is that steady arm elevation location hangs steel ruler laying off schematic diagram;
Fig. 5 is steady arm plane positioning workbench schematic diagram;
Fig. 6 is the accurate setting-out schematic diagram of normalization method;
Fig. 7 is total powerstation lofting positioner central point schematic diagram;
Fig. 8 is flower basket bolt location, steel pipe column upper end schematic diagram;
Fig. 9 is laser plumbing method setting-out steel pipe column top central point schematic diagram;
Figure 10 measures steel pipe column top absolute altitude schematic diagram for hanging steel ruler method.
In figure: 1, the stake heart; 2, position line; 3, stake position; 4, timber; 5, diameter 700 steel pipe column; 6, steel pipe column suspension column ring flat-plate; 7, cross steel plate dowel; 8, adjustable junction steel plate; 9, pre-buried installation foot; 10, steel sleeve; 11, drilled pile sideline; 12, reinforced frame; 13, original state soil layer; 14, steel tape; 15, flower basket bolt; 16, steady arm; 17, concrete; 18, spirit-leveling instrument; 19, levelling pole; 20, plate platform; 21, cultellation reserved opening; 22, steel nail; 23, batten; 24, checkpoint C; 25, frame website B; 26, backsight point A; 27, stake position center point P is designed; 28, setting-out stake position center point P '; 29, laser plummet device; 30, prism; 31, steel pile casting place suitable for reading; 32, total powerstation; 33, reference mark; 34, plumb bob; 35, steady arm anchor rib.
Embodiment
Below in conjunction with concrete case study on implementation, the present invention is described as follows: as a kind of sheltered reverse excavation subway station steel pipe column accurate positioning method of one embodiment of the present of invention, comprise the following steps: (1), steel pipe column pile foundation location survey, (2), rig squareness measurement, (3), the installation of steel pipe column steady arm and location survey, (4) erection of steel pipe column location, wherein (3) step specifically comprises: steady arm elevation location, steady arm plane positioning; (4) step specifically comprises: steel pipe column is vertically located, steel pipe column elevation is checked.Concrete steps are: 1, steel pipe column pile foundation location survey
Absolute altitude at the bottom of the design plane coordinate at the steel pipe column pile foundation center calculated with drawing and stake, the on-the-spot planimetric position adopting total powerstation-pole coordinates lofting mode to release central pile center, and involve 2 orthogonal lead-in wires by pile center's point, carry out and draw stake, so that often check a heart position in piling construction process.
2, rig squareness measurement
O place erection total powerstation at an arbitrary position, until drilling rod unsettled static after, total powerstation is under non-prism NP pattern, measure the horizontal range D of instrument to drilling rod center, then bottom survey record drilling rod and the horizontal direction value of top ad-hoc location and zenith distance, thus calculate the projected length of drilling rod at level and vertical direction, and according to the verticality computing formula of the rig derived
, calculate rig verticality, if verticality is partially within the scope of permissible value, then piling of can constructing.
3, the location survey of steel pipe column steady arm
The while that what the intermediate column (steel pipe column) as one of station agent structure adopted being upper and lower two ends, localization method is fixed.Pipe column lower end location depends on autonavigator, flower basket bolt fine setting location, upper end.
3.1 steady arm elevation location
The elevation location of steady arm adopts and hangs steel ruler laying off, and the instrument mainly used has: the plumb bob, surveyor's staff, marking pen etc. of optical level, levelling pole 1 handle, wooden tripod, 50m steel tape (assay approval), 5kg.Data encasement: the elevation H of on-the-spot level reference mark A
a, the design altitude H in the steady arm leveling board face of certain steel pipe column
b.
As shown in Figure 4: on the ground, steel tape is just being hung on the position near steel pile casting wall, and spirit-leveling instrument is erected at leveling point A and steel pile casting relative intermediate position, to reduce i angle error.Backsight reads the reading a of levelling pole, and forward sight reads the ground reading R of steel ruler
on.Consider the factors such as the long correction of the chi of steel ruler and temperature correction, computing formula is as follows:
(formula 1)
After hanging up properly steel ruler, set up No. 2 spirit-leveling instruments respectively at every turn, read a and R
on, calculate R
underif, the R calculated for twice
underdifference within ± 2mm, then average, then by the survey work of down-hole at steel ruler reading R
underplace's surveyor's staff marks a horizontal line on steel pile casting inwall.Here we are according to actual conditions, hang up properly steel ruler respectively, do horizontal lines mark according to above-mentioned way at steel pile casting inwall corresponding 4 of steel pile casting tube wall cross axis direction, mutually to check, control steady arm installed height mark.
3.2 steady arm plane positioning
Steady arm plane positioning adopts the downward cultellation method of laser, and the instrument mainly used has: total powerstation, 3, wooden tripod, and 2 groups, prism, prism centering rod 1 overlaps, laser plummet.
Steady arm cultellation process is as follows:
1) steel plate workbench is placed on steel pile casting place suitable for reading (as shown in Figure 5), steel plate workbench is wanted steadily, and when people walks about above, steel plate workbench can not vibrate.Adopt total powerstation polar method, by the setting-out of the planar central of steady arm point within the scope of the batten on steel plate workbench, and carry out mark.
2) with gauge point on batten for alignment, steel plate workbench sets up wooden tripod and prism, then adopt naturalization laying off (as shown in Figure 6), accurate setting-out goes out a design coordinate of heart point P.
3) prism is removed from pedestal, note in this process keeping off dynamic foot rest, then laser plummet is placed on pedestal, the batten on steel plate workbench is removed, central point is just thrown in down-hole by the cultellation reserved opening on steel plate by laser plummet.For avoiding plumb aligner cultellation visor not vertical error, during each cultellation, change three directions, if when point position all falls within same point, be namely a heart.Otherwise can produce three direction point A, B, C and form a triangle, now, getting leg-of-mutton circumscribed circle centre point O, is namely a heart.Finally, be welded and fixed steady arm, casting concrete.
4 erection of steel pipe column location
After device concrete to be positioned reaches design strength, carry out the lifting of steel pipe column.Directly can embed steady arm bottom steel pipe column, steel pipe column can be welded with spacer ferrule and embed steady arm bottom it, and its pipe end is firmly located on steady arm cross location-plate, by the bottom of absolute altitude measuring column with the degree of agreement of steady arm.
4.1 steel pipe columns are vertically located
Locate owing to adopting steady arm bottom steel pipe column, top adopts flower basket bolt fine setting, for ensureing the verticality of steel pipe column, only need adopt method shown in (1) step, field lofting goes out steel pipe column center point, and sets up laser plummet on the point of center, open laser target to, make steel pipe column upper and lower center point in same laser beam by adjustment flower basket bolt, then determine steel pipe column and vertically locate errorless.
4.2 steel pipe column elevations are checked
Adopt the top mark hanging steel ruler method measurement steel pipe column high, compare with design load, check the degree of agreement with steady arm at the bottom of post.
During measurement, spirit-leveling instrument is erected at leveling point A and steel pile casting relative intermediate position, to reduce i angle error.The reading a of backsight levelling pole and the upper chi reading R of steel tape measured by spirit-leveling instrument
on, then read the lower chi reading R corresponding with steel pipe column top planes align place
under.If consider the factors such as the long correction of the chi of steel ruler and temperature correction, steel pipe column top absolute altitude computing formula is as follows:
(formula 2)
Its construction way is: by total station survey, the drilling rod verticality correcting rig, guarantee the construction quality in pile hole construction pile hole; Utilize elevation survey method, ground elevation is delivered to down-hole, control the design height of steady arm bottom steel pipe column; Then with total powerstation and laser plummet associating setting-out cultellation location, orient the planar central point of steady arm in down-hole, casting concrete fixed locator, reach after design strength until concrete, hang steel pipe column, again go out steel pipe column top planes central point with total powerstation and laser plummet associating setting-out cultellation, fix with flower basket bolt, build rim of a cup concrete and steel pipe column inner concrete successively, complete the construction at steel pipe column position.
Above-described embodiment is only be described the preferred embodiment of the present invention; not scope of the present invention is limited; under not departing from the present invention and designing the prerequisite of spirit; the various distortion that those of ordinary skill in the art make technical scheme of the present invention and improvement, all should fall in protection domain that claims of the present invention determines.