1. 1 construction survey setting-out content
No. Equipment and tools used by the responsible unit.
1 Building red line and axis positioning, Elevation Surveying and Mapping Institute
General contractor theodolite and total station
2. General contracting theodolite for positioning piles against the line
3. General contracting J2JD laser theodolite and laser plumb instrument for axis measurement.
4 S3 level and steel rule of the general contractor for elevation measurement
5 Verticality General Contracting J2JD Laser Theodolite
6. General Contractor of dimension line Steel Ruler.
1.2 preparation for construction survey
(1) Collect all kinds of relevant data and check the positioning base points.
The data to be collected and prepared for the investigation: the surveying and mapping results of the urban planning department; Engineering investigation report; Construction design engineering drawings and related change documents; Construction organization design and scheme; Surveying and mapping results of underground pipelines and buildings (structures) on the construction site; Determine the scope of the original underground pipelines and underground buildings (structures) that need to be preserved; Positioning and setting-out of site leveling and temporary works.
(2) Preparation of main measuring instruments and meters
Name, model and quantity, and final verification time
Total Station 120** Year 65438+ February
Laser theodolite J2JD220** Year 65438+February
Level S3520** Year 65438+ February
Steel tape 2 ~ 50m 1020 * * Year 65438+ February.
Leveling scale 620** year 65438+ February.
(3) Personnel preparation
① Surveyor: Select qualified personnel with qualification certificates.
② Personnel training: strengthen skills training according to the engineering characteristics before construction.
1.3 engineering positioning survey
(1) plane control survey
① Establishment of site plane control network: Due to the regular overall shape of the building, the four sides of the building extend outward by 5- 10m, and the four side lines intersect to form a mesh control network.
(2) The on-site plane control network adopts traverse network, with the spacing of control lines of 50m, and the control piles are intervisibility, which is easy to measure.
(3) Layout: Layout should be selected in a place where the soil is hard and convenient for long-term preservation, and the top surface is slightly lower than the design elevation of the site.
④ Accuracy requirements of the site plane control network: the control network shall be laid according to the first-class technical requirements. After the layout of building grid is completed, measure the intersection angle of grid axis and the distance between axes, and adjust the control points to meet the requirements.
Main technical indexes of building grid structure
Slope side length (m) error () relative side length error in angle measurement.
Level 1 30 ~ 50 5 1/40000
(2) elevation control survey
① Establishment of elevation control network: Fourth-class leveling is selected as the level of elevation control survey, which is the first-class elevation control of the site. The elevation control network and the plane control network use the same control network, and each control pile point in the control network also serves as the control point of the elevation control network.
The control network adopts leveling method, and no less than four elevation control points are set around the structure, and the distance between the control points is not more than 100m. ..
B point layout: the marking of elevation control points and the embedding of signs shall comply with the relevant provisions of the specification. The location should be in a place where the soil is hard and convenient for long-term preservation, and the pile bottom should be lower than the frozen soil layer. You can also use fixed features or planar control points.
② Accuracy requirements of the elevation control network: the middle traverse reading method is adopted for the fourth-class leveling, and the observation sequence of each station is: back-back-front-front; .
Main technical requirements of leveling
Median error of slope elevation difference per kilometer (mm) The observation times of instrument model leveling rod are poor in round trip, adhesion or ring closure (mm)
The accidental mean error M δ and the total mean error MW are connected with the known points to measure the loop or attached to the flat ground.
Fourth-class 5 10DS3 double round trip 20L0.5
Note: L is the length of the attachment line or closed loop (in Km).
(3) Building alignment and foundation positioning measurement
(1) Establishment of Building Plane Control Network
The control network adopts the cross spindle method. In the process of measurement, we should master the principle from the whole to the part, first survey the control points of spindle piling, and then densely survey other axes on the basis of spindle piling.
② Accuracy grade and technical requirements of building plane control network: Grade II is selected.
Main technical requirements for establishing plane control network
Scope of application of error grade of angle measurement () Relative median error of side length
Secondary frame building12115000
③ Foundation excavation setting-out: After the building plane control network is determined and the line inspection is qualified, the building axis control pile is determined according to the accuracy of the building plane control network, and a small line is drawn along the excavation edge of the foundation trench, and the width of the gray line is not more than15 mm. ..
(4) Setting-out of building foundation.
A. Control the excavation elevation: at the position 100cm away from the design elevation of the trough bottom, lay horizontal piles every 3m. When the whole excavation foundation is excavated near the bottom of the trench, the elevation of the toe of the slope and the grid points of 3m×3m shall be released in time, and the allowable error is 10 mm. ..
B, foundation setting-out: on the cushion, measure and close the outer contour axis of the building. After the calibration is qualified, the detailed axis and related boundary lines will be released in detail with ink lines.
Allowable error of foundation lofting size
Length l, width b, dimension (m), allowable error (mm)
l(B)≤30±5
30