What aspects of knowledge accumulation should be paid attention to in highway surveying

I think there should be two major tasks:

First, elevation measurement: first of all, a temporary leveling point should be set up at our construction site according to the leveling point, and secondly, the elevation of the roadbed should be controlled at any time during the filling and excavation process, and of course, the bridge and culvert tunnel.

The second is plane measurement: that is, traverse measurement, guide the control point to the construction site, establish a number of traverse points, and loft each point of the roadbed in the middle line, and the general practice is to find the coordinates of the point by using the total station lofting.

Of course, it is not something that can be explained in three words.

1. Before the construction of the pavement base, the elevation of all bridge deck pavement layers should be measured and compared with the design elevation. If the difference is large, it should be proposed to the supervision and key fiber construction and design unit to determine the amount of elevation adjustment.

2. The construction measurement of the pavement base focuses on controlling the thickness and width of each layer. When the plane is measured, the center and edge pile position of the layer should be determined. The edge pile position should be 100mm larger than the design width of the layer when lofting, so as to ensure the design width of the layer after compaction.

3. When the elevation is measured, the design elevation should be measured and set on the midline ridge and side line elevation control piles according to a certain inverse number. When working with pavers, the elevation control piles should be adjustable pallets. And the spacing between the piles should not be greater than 10m, and the ramp can be encrypted to 5m.

Aluminum alloy guide beams or 3 wire ropes are placed flat on the elevation control pile. When the wire rope is adopted, more than 20 steel drills are smashed into the firm ground every 100m, and 1t inverted chain is fixed on it to tighten the wire rope, so that it can be placed smoothly on the adjustable pallet that has been measured and set elevation. During the paver journey, there should be a special person to watch over the pallet, and if the pallet is moved or the wire rope falls off the pallet, the elevation of the place should be remeasured immediately.

4. When the section is constructed, the plane and elevation lofting should enter the adjacent construction section 50 100m to ensure the smooth and beautiful line type at the section junction.

5. At the entrance and exit of the ramp or other irregular lots, the elevation lofting should be carried out according to the grid provided by the design.

1. Control measurement: according to the needs of road engineering, plane control measurement and elevation control measurement are carried out;

2. Topographic map surveying and mapping: according to the design needs, field survey the strip topographic map near the road;

3. Centerline measurement: measure the location of the road in the field according to the design requirements;

4. Longitudinal and cross-sectional map surveying and mapping: determine the height and fluctuation of the ground in the direction of the center line of the road and perpendicular to the direction of the center line, and draw the longitudinal and cross-sectional map;

5. Construction survey: according to the design requirements and construction schedule, various pile points are staked out in time as the construction basis.

There is not much information to measure, first of all, there must be a ledger (record what you do every day); Road land acquisition boundary, red line, open line, middle line, edge line of the pay-off record, with a simple diagram (draw the middle line, edge line and offset, according to the drawing pile distance on the line, if the data clerk has special requirements, can also be appropriate to encrypt the pile point), generally there will be a culvert in the road, the culvert of the foundation pit excavation, foundation, the measurement of the eight-character wall of the pay-off record written, generally to attach a simple diagram; If there is a bridge, the pile foundation, columns, cushion caps, tie beams, cover beams, and stepping stones of the bridge are written, these materials can be written in advance, put up, what the data room needs to provide, find out and copy it to her, and other information depends on the specific situation.

<> the key points of highway subgrade construction measurement is very important, the measured data should be accurate, and it will be very helpful for the actual construction, and the processing of every detail is very critical. Zhongda Consulting will introduce to you the key points of highway subgrade construction surveying.

1. Restore the center line and side line once for each layer of the subgrade of the fill section and carry out elevation measurement. In the top of the road bed, it should be controlled according to the design longitudinal and cross-sectional data. After reaching the design elevation of the roadbed, the center line of the roadbed and the edges on both sides should be accurately staked out, and the design elevation of the top of the roadbed should be accurately measured and set on the center and both sides of the pile, according to the design line, width, slope, elevation control and self-inspection, self-inspection qualified and reported to the supervision engineer for confirmation, before the next process construction.

2. The subgrade excavation section should be calculated according to the design elevation and slope slope and the upper mouth slotting line should be released. Restore the center line and edge line at each step of digging depth and carry out elevation measurement. Elevation points should be laid at the retaining walls on both sides or other stable and reliable parts.

When digging to the top of the roadbed about 1m, the elevation point should be jointly measured with the attached high-level point.

3. The spacing of the middle pile on the straight line should not be greater than 50m, and the horizontal curve should be 20m. When the terrain is flat and the curve radius is greater than 800m, the pile spacing can be 40m. When the radius of the highway curve is 30 60m and the length of the easing curve is 30 50m, the pile spacing should not be greater than 10.

When the radius of the highway curve is less than 30m or the length of each curve is less than 30m, the spacing between the middle piles should not be greater than 5m.

4. According to the needs of the work, the broken chain piles of the starting and ending piles, 100-meter piles and flat curve control piles can be measured, and the piles should be added according to the changes in the vertical curve.

5. Within the backfill range of the platform on both sides of the abutment, the layered filling elevation line should be marked on the platform back.

6. For structures such as pipe culverts, the slotted center line and edge line should be measured first. Once the trough bottom elevation is reached, the elevation is detected and the centerline is restored. After the pipe foundation is completed, the elevation of the top surface of the pipe base is detected, and the center line or structural edge line is accurately measured and popped up on the top surface of the pipe base.

The measurement data are as follows:

1. Control the measurement data, according to the needs of road engineering, it is necessary to carry out plane control measurement and elevation control measurement, and then organize it in the book;

2. Topographic map surveying and mapping data, according to the design needs, field survey of the strip topographic map near the road, and record it in the register;

3. The measurement data of the middle line, the road location measurement is set in the field according to the design requirements, and recorded in the register;

4. Longitudinal and cross-sectional map surveying and mapping data, determine the height and fluctuation of the ground in the direction of the road centerline and perpendicular to the centerline direction, and draw the longitudinal and cross-sectional maps;

5. Construction survey data, according to the design requirements and construction progress in a timely manner lofting various pile points as the basis for construction.