Specifications for aerophotogrammetric field work 1:5000, 1:10000 topographic maps
Some standard content:
National Standard of the People's Republic of China
1:5 000 1:10 000 Topographic Maps
Specifications for erophotogrammetric tieldwork 1:5000.1:1000 topographic maps1 Subject content and applicable scope
GB/T 13977—92
This standard specifies the specifications, accuracy and basic requirements for field work of surveying and mapping 1:5000.1:10000 topographic maps by aerial photogrammetry.
This standard applies to aerial photogrammetric field work of 1:5000.1:10000 topographic maps. According to this standard, the topographic maps surveyed and prepared are mainly used by various departments of the national economy for surveying, planning, design and scientific research, and can be used as basic data for reducing smaller scale topographic maps or thematic maps. 2 Reference standards
GB 5791 1: 5000, 1: 10000 topographic map diagram (B section 13989 National basic scale topographic map division and numbering ZB3A76003, Basic regulations for field electronic records ZBA75001 Surveying and mapping technical design regulations
ZB A75002
Surveying and mapping product inspection and acceptance regulations
ZCH1021: 5000, 1: 10000 scale topographic map aerial photography indoor and outdoor comprehensive judgment method operation procedures 3 General provisions
3.1 Specifications of topographic maps
3.1. 1 Projection, coordinate system and elevation benchmark 1:5000.1:10000 topographic map adopts Gauss-Kruger projection, divided into 3° zones. The plane coordinate system adopts the 1980 Xi'an coordinate system; the elevation adopts the 1985 National elevation datum. 3.1.2 Division and numbering of topographic maps
The division and numbering of topographic maps shall be carried out in accordance with GB/T13989. In special cases, such as areas close to national borders or wide waters, there is only a small part of land in the map sheet, which can be merged into the adjacent sheet for broken map outline processing. The sheet number of the broken map sheet is after the main map sheet number, separated by commas. 3.1.3 Topographic classification
Terrain categories are divided according to the ground inclination angle and height of most of the map sheet, as stipulated in Table 1. When there is a conflict between the height difference and the ground inclination angle, the ground inclination angle shall prevail.
Approved by the State Bureau of Technical Supervision on December 17, 1992 and implemented on July 1, 1993
Terrain categories
Hills
Mountains
3.1.4 Basic contour intervals
Ground inclination angle
GB/T 13977--- 92
1:5000
20~150
150--300
Basic contour intervals are divided according to terrain types, as specified in Table 2. Height difference, m
1:10000
20~150
150--500
One basic contour interval is generally used in a map. When the basic contour line cannot show the landform features, an intermediate curve should be added, and an auxiliary curve can be added if necessary. Table 2
Terrain type
1:5000||t t||Hills
Mountains
3.1.5 Density of elevation annotation
Basic isotropic interval
1:10000
Elevation annotation points should be selected on obvious terrain points and terrain feature points. The density is 10 to 20 for flat land and hills, 8 to 15 for mountains, high mountains and areas with few terrain feature points per 100cm2 on the map. 1 to 3 for every 100cm on the contour annotation map. 3.1.6 Symbols and annotations of topographic maps
The symbols and annotation specifications of topographic maps shall be implemented in accordance with GB5791. 3.2 Accuracy of topographic maps
3.2.1 The mean error of the plane position of terrain points on the map to the nearby external control points shall not exceed ±0.50mm for flat land and hills, and ±0.75mm for mountains and high mountains.
3.2.2 The errors in the calculation of elevation annotation points and contour lines relative to nearby field control points shall not exceed the requirements of Table 3. Table 3
Map scale
Terrain type
Elevation annotation point
Contour line
1:5000
Hillary
(Terrain
Transformation point)
Mountainous
(Terrain
Transformation point)
Hillary
(Terrain
Transformation point)
Mountainous
《Terrain
Transformation point）
Mountainous on the map, when the contour line of the mountainous area cannot directly find the corresponding position to measure its elevation accuracy in the field, the elevation error of the contour line can be calculated according to formula (1). When the calculated value is less than the value specified in Table 3, according to the provisions of Table 3, ma=±(a+b - tga
Wuzhong: Recruitment n--Meanwhile the elevation error of the contour line, m: GB/T13977-92
α-Meanwhile the elevation error of the elevation annotation point·m;6--Meanwhile the plane position error of the feature point, m:α--Ground inclination angle near the inspection point, (\). 3.2.3 For special difficult areas (large areas of forests, deserts, Gobi, marshes, etc.), the plane position error of the feature point shall be relaxed by 0.5 times according to 3.2.1, and the plane error shall be relaxed by 0.5 according to Table 3. 3.2.4 The mean error of the plane position of the advanced terrain control point to the nearby national level triangulation point shall not exceed ±0.05mm on the map. The mean error of the plane position of the photo plane and the level control point to the nearby national level triangulation point or advanced terrain control point shall not exceed ±0.1mm on the map. The mean error of the elevation of the advanced terrain control point and the photo elevation control point to the nearby leveling point or triangulation point shall not exceed 1% of the basic contour interval in flat land, hilly land, and mountainous land (the requirements for commercial mountainous land are met). 3.2.5 This specification takes twice the mean error as the maximum error. .3 Requirements for aerial photography data
The 15000, 1:10000, 1:25000, 1:50000, and 1:100000 scale topographic map aerial photography specifications formulated by the State Administration of Surveying and Mapping in 1980 shall be followed.
3.4 Requirements for other operation methods
On the premise of meeting the mapping accuracy of this specification, new technologies and methods not listed in this specification may be adopted, but they shall be clearly specified in the project design document.
3.5 Technical design
Follow ZBA75 001.
4 Arrangement of image control points
4.1 Classification of image control points and requirements for the position of image control points on images 4.1-1 Classification of image control points
Image control points are divided into three categories: surface control points (referred to as plane points), elevation control points (referred to as elevation points), and level control points (referred to as level points).
Plane points only measure the plane coordinates of the point, elevation points only measure the level of the point, and level points must measure the plane coordinates and elevation of the point. In the illustration, > indicates a plane point, @ indicates a level point, ● indicates an elevation point, and represents an image principal point. 4. 1. 2 Requirements for the position of image control points on images a. The selected image control point position target image should be clear and easy to judge and measure in stereo. When the day mark conflicts with other image conditions, the target conditions should be carefully considered;
b. The distance between the image control point and various marks on the image should be greater than 1mm, and the distance from the edge of the image should not be less than 1cm (18cm×18cm image frame) or 1.5cm (23cm×23cm image frame)
c. The image control point should be selected near the center line of the lateral overlap, and the distance from the azimuth line should be greater than 3cm (18cm×1Bcm image frame) or 4.5cm (23cm×23cm image frame). When the lateral overlap is too large, the distance from the azimuth line should be greater than 2cm (18cm×18cm image frame) or 3cm (23rm×23cm image frame). Otherwise, the points should be arranged separately. Because the side check is small, when points need to be arranged separately, the vertical distance of the control range shall not be greater than 2cm
4.2 Regional network points
4.2-1 Division of regional network
, the division of the network is generally divided neatly according to the map line, and can also be divided according to the aerial photography division, terrain conditions and other conditions, and strive to make the network shape square or rectangular.
The size of the area or network and the span between the photo control points are mainly determined by factors such as mapping accuracy, aerial photography data conditions and the processing of system errors.
4.2.2 Arrangement of control points
GB/T 13977--92
4.2.2.1 The regional network flat high points are arranged according to the surrounding 6-point method, the surrounding 8-point method, or the surrounding multi-point method, as shown in Figure 1, Figure 2. Figure 3, Figure 4. Wine
4.2.2.2 When using the method of double covering a map with a central image, the area or network is within 16 maps and the 6-point method is used; for more than 16 maps (including 16 maps) and within 48 maps, the 8-point method is used; for more than 48 maps (including 48 maps), the multi-point method is used to lay out the flat and high points. The span between lateral control points: flat land and ridge land is not more than 2 routes, and mountainous and high mountainous land is not more than 3 routes. The span between two adjacent control points in the heading will be estimated by the route network accuracy estimation formula (G1) in the appendix. 4. 2. 2. 3 When a map has more than 2 routes covered, flat land and ridge land are covered with 4 maps as one area, and the 6-point method is used. The point method is used to set the horizontal and high points. For the regional network with more than 4 bridge maps, the surrounding 8-point method is used to set the horizontal and high points. For mountainous and high mountainous areas, 6 maps are used as one area. The 6-point method is used to set the horizontal and high points. For the regional network with more than 6 maps, the surrounding 8-point method is used to set the horizontal and high points. The span between the lateral control points is no more than 3 routes for flat and hilly areas. It is no more than 4 routes for mountainous and high mountainous areas. The span between adjacent control points in the heading is estimated by referring to the accuracy estimation of the shallow network in Appendix G (G1). 4.2.3 Setting of elevation control points
4.2.3.1 The elevation points are arranged in a grid pattern. On the basis of the horizontal and vertical points arranged in 4.2.2, 3 rows, 4 rows, and no more than 5 rows of elevation control points are arranged in the regional network in a straight heading direction, as shown in Figures 5, 6, and 7. There should be a pair of elevation points at both ends of the route. The span between two adjacent rows of elevation control points in the heading direction is estimated by referring to the route network accuracy estimation formula (G2) in Xie Lu G. Q
GB/T13977—92
4.2-3.2 After determining the size of the regional network based on the horizontal and vertical control points, connect the public Formula (G2) estimates the number of rows of elevation control points. When the estimated number is greater than 3 rows but less than 4 rows, the elevation control points can be arranged in 3 rows, and additional elevation points can be arranged near the middle of the two adjacent elevation control points on the upper and lower sides of the network, as shown in Figure 8. When the estimated number is greater than 4 rows but less than 5 rows, the elevation points can be arranged in 4 rows, and additional elevation points can be arranged in the middle of the two adjacent rows of elevation control points on the upper and lower sides of the network.
When the estimated span between two adjacent rows of elevation points is less than 4 baselines, the elevation points can be arranged in 4 rows, and additional elevation points can be arranged on the upper and lower sides of the network, as shown in Figure 9 .
4.2.3.3 In high mountainous areas and special difficult areas, there should be a pair of elevation points at both ends of each route. The middle of the network can be evenly distributed with elevation points. The span between two elevation points on the route should not be too large. According to the estimated value of formula (G2). 4.2.3.4 In irregular areas, the network points are generally distributed at the turning point. When the baseline is used, the elevation points are distributed. When there are more than two baselines, the elevation points are distributed. See Figure 10. The supplementary flight route should be equipped with level control points at the three-degree overlap of the route, as shown in Figure 11. Figure 10
GE/T 13977—92
4.2.3.5 When arranging points in the regional network, the points shall meet the requirements of the image conditions in Article 4.1.2 and shall also meet the following requirements: 1. The control points around the regional network shall be able to control the area of surveying and mapping. The free map edge shall be arranged outside the map outline. The control points at both ends of the route shall not deviate from the left by more than 1 baseline (18cm×18cm image frame) or 2 baselines (23cm×23cm image frame). 4.3 Full field point arrangement
.4.3.1 When the correction instrument is used for image correction, a plane point shall be arranged at each of the four corners of the effective area. Figure 12 is for interval correction, and Figure 13 is for piece-by-piece correction. If zoning correction is required, the plane points in Figure 12 and Figure 13 are changed to flat-high points. ?
4.3.2 Parallax mapping is only for mapping. Four high points and · elevation points are arranged at the four corners of the survey area of each image pair, as shown in Figure 11. @
Figure 14
4-3-3 Orthographic projection operation and omnidirectional mapping, each stereo image pair is surveyed and · flat points are arranged at the four corners of the area, as shown in Figure 15.4.3.4 Elevation full field point layout changes the flat-high points in Articles 4.3.2 and 4.3.3 into elevation points. In-house control densification solves the plane mark of the elevation point. The required horizontal and high control points shall be implemented in accordance with the provisions of 4.2.2 and 4.3.5. In addition to meeting the requirements of 1.1.2 and 42.3.5, the full field point distribution image conditions shall also meet the following requirements: a. The deviation of the four azimuth points used for stereo mapping from the straight line passing through the main point of the image and perpendicular to the azimuth line shall not exceed 1 cm, and the maximum shall not exceed 1.5 cm, and the figure formed shall be as rectangular as possible: GB/T 13977—92
hThe height point measured by the parallax plotter should be located in the middle of the network orientation point, and the distance from the two orientation points and the azimuth line should be greater than 1.5cm, and the distance from the line connecting the two orientation points should not be greater than 1cm
c. When the method of covering a map with a central image is used, the distance between the image control point and the map outline point should not be greater than 1cm, and the maximum distance should not be greater than 1.25cm (not greater than 5cm on the map board) 4.4 Single route point layout
4.4.1 Each route is laid out with the six-point method or the five-point method. The horizontal and vertical points are shown in Figures 16 and 17. o
4.4.2 The span between the control points is calculated by the route network accuracy estimation formula (G1) (G2) in the appendix and then multiplied by V2. 4.5 Point layout in special situations
When it is impossible to layout the image control points as normal due to special situations such as the main point of the image, the standard point falling into the water, the bay island area, and the leakage of aerial photography, the control points shall be arranged according to the specific situation based on the principle of meeting the requirements of internal control encryption and stereo mapping. The conditions of the points on the image can be appropriately modified.
5 Advanced terrain control survey
In addition to the national level points, the small diagonal points with a mean error of 5\ and the electromagnetic wave ranging guide points can be reasonably arranged according to the actual situation and specific requirements of the survey area, as well as the measurement of external leveling, theodolite blue angle elevation route and electromagnetic wave ranging elevation guide line. This is the basis for image control measurement.
5.15\Level plane control measurement basis
5.1.1 Electromagnetic wave ranging conductor
The electromagnetic wave ranging conductor is based on the national level point and is arranged into a single connected conductor or a conductor network with nodes. The instrument should use a positive-level radio wave distance meter with a ranging error (nominal accuracy) of no more than 10mm per male black. The main technical requirements for the electromagnetic wave ranging conductor shall not exceed the requirements of Table 4. 5. 1.1. 1
Scale
1: 5 000
110000
Jiang: In the table, the number is the number of turning angles,
5.1.1.2 Node conductor
Total length of conductor
Relative closure
1/14 000
1/12000
Azimuth
Closure error
Medium error
Horizontal return effect
Clarity number
The length and number of sides between the node and the starting and closing points can be 0.7 times that in Table 4; the length and number of sides between nodes can be 0.5 times that in Table 4.
5.1.1.3 The layout of electromagnetic wave ranging conductors requires that the conductors or conductor networks with nodes should be laid out in an equilateral manner between grade points, between grade points and nodes, and between nodes.
Straight extension form, the difference between its turning angle and 180° is generally not more than 45°h.
GB/T13977-92
The height difference between the two end points of the conductor side should meet the value calculated according to formula (2). h≤250 -S
Where: h——-height difference between the two ends of the conductor side, mi-conductor side length, km.
c. The conductor side length is generally 500~2000m. 5.7.1.4 Distance measurement requirements for electromagnetic wave distance measurement lines a. Before operation, the electromagnetic wave distance meter used should be inspected. (2)
Distance measurement should be carried out under the conditions of stable atmosphere and clear image. If the air flow is seriously affected during the distance measurement process, b.
should stop the single measurement
c. The length of the line is measured twice in one way, and the number of readings is four times as one measurement. The difference between the readings of the same measurement should be less than 10mIn, and the difference between the turns should be less than 13mm:
Each side measures - meteorological data, the temperature is read to 0.5℃, and the air pressure is read to 133.322Pa (1mmHg). d
5.1.2. Small triangulation measurement
Small triangulation measurement is to encrypt small triangulation points on the basis of national grade points, and usually adopts linear lock, plug-in network, plug-in point and other methods for layout. 5.1.2.1 The sugar content and specifications of the small triangulation point shall not exceed those specified in Table 5. Table 5
Meanwhile error in angle measurement
5.1.2.2 Linear lock
Starting length of side
Relative mean error
1/40 000
Length of weakest side
Relative mean error
1/20000
Number of horizontal angle measurements
Linear lock should be close to the tactile limit, and each triangle in the lock should be equilateral. The distance angle should generally not be less than 40°, and should not be less than 30° in most cases. The sum of the graphic strength coefficients of the lock should not be greater than 85 (not greater than 100 for linear double locks). When conditions permit, the linear lock must be tested with an additional inspection angle. The number of triangles, side lengths and total length of the linear lock should not exceed the requirements of Table 6. Qiu6
Drawing scale
1 1 5 000
1 : o 00a
Number of triangles
Length of triangle side
The requirements for triangle locks with starting sides at both ends or one end are the same as those for linear locks, but no additional inspection angle is required. 5.1.2.3 Insertion network
Linear lock length
Insertion network strives to lay pipes evenly, and the internal angle of each triangle is generally not less than 30°. In the middle of the network, some internal angles can be not less than 20°. The sides of the angles of the insertion network should be observed in opposite directions, and some reverse observations can be made in one direction in difficult areas. 5.1.2.4 Insertion point
The intersection angle of the insertion point should be not less than 30°, and the intersection side length should not exceed 6km for 1:5000 mapping; and not more than 12km for 1:10000 mapping. When the distance between the insertion point and the national level point or between two insertion points is shorter than the average side length, a joint survey figure should be formed as much as possible. The triangle sides of the insertion point should be observed in opposite directions, and individual sides in difficult areas can be observed in one direction. 5.1.3 Point selection and stone burial
a. The point selection work should be based on a full investigation of the existing control points in the survey area, and according to the task requirements, known results and the natural geographical characteristics of the survey area, etc.: formulate the most reasonable layout plan. The selected points should ensure good visibility and facilitate observation and expansion; GB/T 13977---92
In the survey area, if there is no national level point on the map sheet passed by the wire and the lock net, the high-level terrain control point should be buried with stones (one for each h.
map). The point description is recorded in the map book: c. The specifications and burial requirements of the high-level terrain control point marker stone are shown in Appendix E; d. The point name is the nearby geographical name. 5 1. 4 Horizontal angle observation
5.1.4.1 Horizontal angle observation adopts the direction observation method. When observing more than 7 directions, the observation should be made in groups and the zero direction should be adopted. When observing 3 directions, it is not necessary to return to zero. The degree value of the position change of each measuring circle is 180° divided by the specified number of measuring circles. 5.1.4.2 When the eccentricity of the measuring station or the sighting point is greater than one eighty thousandth of the distance from the measuring station to the nearest observation point, the centering correction should be carried out.
The horizontal angle observation limit error should not exceed the provisions of Table? 5, 1. 4. 3
Half-round Jiangcen difference
2 mutual coupons
Each round has the same direction difference
Triangle closure difference
DJ2(°)
5-1.4.4 When the observation result exceeds the limit, it should be re-measured according to the following provisions: et)
2℃ five coupons or round difference exceeds the limit, it is allowed to re-measure the exceeded direction. When re-measurement, the starting direction should be measured together; a
b, when the number of re-measured directions in the round exceeds the number of measured directions, the round should be re-measured. When the zero difference or the 26h difference of the starting direction exceeds the limit, the round should also be re-measured;
The complete round re-measured due to exceeding the limit is called a single round. When the number of re-measured rounds at a station exceeds one third of the total rounds or the station is re-measured due to the closure error exceeding the limit, the station should be re-measured. 5.1.5 The following tolerance checks should be carried out on the field observation data: a. The mean error of angle measurement of small triangulation is calculated according to formula (3): mg=±V[Ww/3n.
Wu: w
triangle closure error, (\);
number of triangles. The mean error of angle measurement m of traverse measurement is calculated according to formula (4): 1mg=
Where: — azimuth closure error of the attached traverse or closed loop; N—the number of stations when calculating f:
N—the number of attached traverses or closed loops. c. The closure error W of the azimuth recording and the limit difference of the closure error W of the extreme condition are calculated according to formula (5) (6): W+s10\s
GB/T 13977-92
W$10\/[a]
W ... The adjustment of linear locks (nets) and triangular locks may not include coordinate conditions, but should include polar conditions and circular conditions. The side conditions should be included in the angle locks with starting edges at both ends;
The insertion network adjustment should use strict adjustment as much as possible. When coordinates are urgently needed, they can be divided or split into linear locks for calculation. The coordinate difference of the coincident points should not exceed Figure I: 0. 1nm p
d. The insertion points can be calculated using various typical graphic adjustments:,: The adjustment of the traverse points is carried out according to the route or the traverse network with nodes, using a simplified method. The traverse elapsed length should be converted to the length correction on the mean water surface and Gauss projection surface: ". The adjustment calculation is based on the provisions of Table 8, Table 8
Observation direction value
Various political correction numbers
5.2 Elevation control measurement
5.2.1 Leveling
Logarithm or function
Standard calculation
Azimuth increase
Leveling measurement is generally applicable to flat areas. Leveling routes should start and end at national leveling points of fourth order or above or triangulation points or commercial-level terrain control points that have been measured by fourth order leveling. Leveling points after adjustment can be developed again. 5.2.1.1 Leveling is difficult to attach. One-way measurement is used for the main route, and round-trip observation or one-way double measurement is used for the branch line. Use a double-sided ruler for observation The reading of the black and red side or the reading of the single-sided ruler twice, read to millimeters. The difference of the reading of the black side of the same ruler or the difference of the two readings shall not exceed 4mm. The difference of the height of the black and red side of the front and rear rulers shall not exceed Gmm.
5.2.1.2 The distance from the instrument to the ruler shall not exceed 100m in general. When the image is particularly clear and stable, it can be relaxed to 150m: if it crosses a ditch or river, it can be relaxed to 200~-250m. The difference of the front and rear scales shall not exceed 20m; the cumulative difference of the front multiple scales shall not exceed 100m. 5.2.1.3 When working, observations should generally be completed at a fixed point; three water piles driven into the ground can also be used as transfer points. After a break, when the difference in height between the two transfer points is within 6t, forward observations can be continued. 5.2.1.4 The total length and closure error of the equal outer water beach route shall not exceed the provisions of Table 9. Table 9
Attached route total length
Note: 1 is the total length of the route, km
5-2.2 Theodolite trigonometric height route||t t||Full length of branch line
Tread line closure error, round trip measurement
or one-way double measurement error-mtn
(When L is less than 1km, it is calculated as 1km)
Theodolite three-dimensional elevation route measurement is suitable for hilly areas, mountainous areas and high mountainous areas. The starting and closing points of the route should be triangulated points or high-level terrain excavation points that have been measured by leveling above the standard level. Difficult areas. If the height error of the national standard triangulation point does not exceed 0.25m in hilly areas and 0.5m in mountainous areas, it can also be used as the starting and closing points of the route, but the total length of the route should not exceed 0.7 times the total length specified in Table 11. 5.2.2. 1 The vertical angle of the theodolite trigonometric elevation route should be observed back and forth. 5.2.2.2 The re-right angle observation record of the theodolite trigonometric elevation route shall be taken to the second, and the instrument height and the current elevation shall be recorded to the centimeter. 5.2.2.3 The number of vertical angle observation measurements and the tolerance shall be in accordance with the provisions of Table 10. Table 10
Number of measurement rounds
Middle wire method
Three wire method
Difference between vertical angle measurement rounds and index difference
5.2.2.4 The tolerances of the theodolite trigonometric elevation route shall not exceed the provisions of Table 11. Table 11
Terrain type
Hills
Mountains, high mountains
Note: 5 is the side length, km.
Total length km
Total length closure error.m
0. 05 VTs-j
Round trip error is poor m
5.2.2.5 When the theodolite trigonometric elevation route is laid out according to the nodes, the maximum distance between the node and the starting and closing points is 0.7 times the total length of the route. 5.2.3 Electromagnetic wave ranging elevation line
The starting and closing points of the electromagnetic wave ranging elevation line should be triangulated points or high-level terrain control points that have been measured by leveling above the standard level. The starting and closing points of the elevation line in difficult areas shall comply with 5.2.2 national level triangulation points with specified elevation accuracy, the total length of the route shall not exceed 0.7 times the total length specified in Table 12.
5.2.3.1 The electromagnetic wave ranging elevation line can be measured separately or together with the electromagnetic wave ranging line. 5. 2. 3. 2
5. 2. 3. 3
The vertical angle of the electromagnetic wave ranging elevation line shall be observed back and forth. The number of measurement rounds and the limit difference shall be implemented in accordance with the provisions of 5.2.2.3. The various limits of the electromagnetic wave ranging line shall not exceed the provisions of Table 12. Table 12
Energy category
Mountainous land
Mountainous land
Note, S is the side length, km.
Maximum side length
Total length of business route
Round trip height difference
5.2.3.4 When the electromagnetic wave ranging height traverse network is laid out according to the nodes, the maximum distance between the node and the starting and closing points is 0.7 times the total length of the route. 5.2.3.5 The electromagnetic ranging height traverse measurement can replace the standard leveling measurement and can be used alternately with the standard leveling. The starting and closing points and the number of developments of the traverse are the same as those of the standard leveling. The tolerances of each item shall not exceed the provisions of Table 12. 5.3 The requirements for recording the horizontal angle, vertical angle, distance measurement, etc. shall be implemented in accordance with the provisions of 6.7.5. 6 Photographic control measurement
6.1 Accuracy and requirements of photographic stinging points GB/T 13977-92
6.1.1 The stinging point error of the plane control point and the height control point shall not be greater than 0.1mm on the photo. Elevation control points should also be accurately punctured. 6.1.2 Points should be punctured on the control film with the clearest image of the point. The hole diameter should not be greater than 0.1mⅡ and the points should be punctured thoroughly. If the puncture is off, the film should be changed and re-punctured. Double holes are not allowed.
6.1.3 National-level triangulation points, leveling points, and high-level terrain control points with buried rocks should be punctured on the control film with the same puncture accuracy as plane control points: When they cannot be punctured accurately, water-pushing points can be punctured according to the method of measuring broken points. Triangulation points and buried rock points are indicated by lines at the corresponding positions on the front and back of the film, and the position of the points is explained and a sketch of the point position is drawn. 6.1.4 The puncture points of the control points on the film should be checked by a second person on the spot. 6.2 The puncture point and ear mark of the film control point
6-2.1 The plane control point should be selected at a position where the point can be accurately judged, such as the intersection of linear features or the corner of the feature. The intersection angle must be good (30-150°). In areas with sparse features, the end point of the linear feature, the slightly pointed mountain top or the center of the point feature with an image less than 0.3mm can also be selected. In forest areas, the puncture point can be selected on the tree top or tree crown that can be accurately judged. 6.2.2 The puncture point target of the elevation control point should be selected in a place where the elevation changes little, and the intersection of linear features and flat mountain tops are suitable. Narrow gullies, sharp mountain tops and slopes with sharp elevation changes are not suitable for selection as puncture point targets. 6.2.3 The monthly mark of the horizontal and vertical control points should meet the requirements of both plane control points and elevation control points. 6.2.4 When the control point is pierced on the tree crown or the piercing point is covered by vegetation, and the ground image cannot be clearly seen on the film, the vegetation height at the piercing point should be measured and noted by 0.1m. If the vegetation grows larger than that during aerial photography, the vegetation height during photography should be noted. When the point is pierced on the top of a feature that is higher than the ground, the ratio of the top to the ground should be noted to 0.1-1, and the measured value should be noted on the back of the film. When the point is pierced on the edge of a feature such as a steep slope, it should be noted on the left side of the film whether it is pierced above or below the slope, and the ratio of the slope should be noted. 6.2.5 All control points of the film must be piled or fixed on the spot. 6.3 Decoration of control points of the film
6.3.1 On the front of the control film, triangulation points are represented by regular triangles, buried stone points are represented by squares, control points of the film are represented by circles, and leveling is represented by heart symbols. Points that cannot be accurately punctured shall be decorated with corresponding dotted line symbols, but level points shall be decorated with solid line symbols. The reverse length or diameter of the symbol is 7mm. The symbols of level points and elevation control points are green, and other symbols and notes are red. On the reverse side of the control film, a point sketch shall be drawn to illustrate the position of the puncture point. The size of the sketch is 2cm×2cm. For elevation control points of the puncture target, it is not necessary to draw a drawing, only an explanation is given. The reverse side of the film shall be decorated with pencil, and the shape and size of the symbol shall be the same as the front side. On other control films, only the corresponding symbol with a diameter or side length of 1c shall be used to transfer the control point on the front side, and the point name (battle point) shall be annotated on the adjacent route film. 6.3-2 When the control points of adjacent areas are shared, the control films of the adjacent areas shall be transferred, and the sheet number and film number of the actual puncture film shall be added. 6.3.3 The puncture point, transfer point, and inspector shall all sign on the reverse side of the film. 6.3.4 The finishing format of the control film is shown in Appendix C. 6.4 Numbering of film control pointsbzxZ.net
The numbering of film control points shall be specified in the technical design document. 6.5 Plane measurement of film control points
6.5 1 General rule is
6.5.1.1 The plane coordinates of the film control points are usually determined by electromagnetic wave ranging combined with wires, branch wires, two-angle locks (linear locks), intersections and lead points. The measurement accuracy shall comply with the provisions of Article 3.2. 4. 6.5.1.2 The number of developments of electromagnetic wave ranging combined with wires, triangulation locks (linear locks) and intersection methods. Starting from the triangulation point or advanced terrain control point: no more than three times; when developing in conjunction with two-angle points or advanced terrain control points, no more than four times. The last control point shall not develop a lead point. 6.5.1.3 The points on the triangular lock (linear lock) and electromagnetic wave ranging attached conductor can develop each other and develop intersection points, but the intersection points cannot be used as the starting and closing points of the two-angle lock (linear lock) and the conductor. 6.5-1.4 When it is difficult, the regression conductor can be used, but the starting point must be checked and confirmed to be correct, and the inspection angle should be measured at the point to be determined. The regression conductor cannot be further developed.
6.5.1.5 When laying attached conductors according to nodes, the route length and number of sides between the node and the starting point can be 0.7 times that in Table 13,1m. If the vegetation grows more than when the aerial photography was taken, the height of the vegetation at the time of photography should be noted. When the point is pierced on the top of a feature that is higher than the ground, the ratio of the top to the ground should be noted to 0.1-1, and the value noted should be noted on the back of the film. When the point is pierced on the edge of a feature such as a steep slope, it should be noted on the opposite side of the film whether it is pierced above or below the slope, and the ratio of the slope should be noted. 6.2.5 All control points of the film must be piled or fixed on the spot. 6.3 Decoration of control points of the film
6.3.1 On the front of the control film, triangulation points are represented by regular triangles, buried stone points are represented by squares, film control points are represented by circles, and leveling is represented by centroid symbols. Points that cannot be accurately pierced are decorated with corresponding dotted line symbols, but leveling points are usually decorated with solid line symbols. The reverse length or diameter of the symbol is 7mm. The symbols of leveling points and elevation control points are green, and other symbols and notes are red. On the reverse side of the control film, draw a sketch of the points on the spot to explain the location of the points. The size of the sketch is 2cm×2cm. For the elevation control points of the target products, it is not necessary to draw a map, only to add an explanation. The reverse side of the film shall be decorated with pencil, and the shape and size of the symbols shall be the same as those on the front side. On other control films, only the corresponding symbols with a diameter or side length of 1c shall be used to transfer the control points on the front side, and the point names (battle points) shall be annotated on the adjacent route film. 6.3-2 When the control points of adjacent areas are shared, the control films of the adjacent areas shall be transferred and the sheet number and film number of the actual film shall be added. 6.3.3 The person who punctures, transfers and inspects shall all sign on the reverse side of the film. 6.3.4 The finishing format of the control film is shown in Appendix C. 6.4 Numbering of control points on the film
The numbering of control points on the film shall be specifically specified in the technical design document. 6.5 Plane measurement of photo control points
6.5 1 General rules are
6.5.1.1 The plane coordinates of photo control points are usually determined by electromagnetic wave ranging with wire, branch wire, two-angle lock (linear lock), intersection and lead point, etc. The measurement accuracy should meet the requirements of 3.2. 4. 6.5.1.2 The number of developments of electromagnetic wave ranging with wire, triangulation lock (linear lock) and intersection method. Starting from the triangulation point or advanced terrain control point: no more than three times; when developing with two-angle points or advanced terrain control points continuously, no more than four times. The last control point shall not develop a lead point. 6.5.1.3 The points on the triangular lock (linear lock) and electromagnetic wave ranging attached conductor can develop each other and develop intersection points, but the intersection points cannot be used as the starting and closing points of the two-angle lock (linear lock) and the conductor. 6.5-1.4 When it is difficult, the regression conductor can be used, but the starting point must be checked and confirmed to be correct, and the inspection angle should be measured at the point to be determined. The regression conductor cannot be further developed.
6.5.1.5 When laying attached conductors according to nodes, the route length and number of sides between the node and the starting point can be 0.7 times that in Table 13,1m. If the vegetation grows more than when the aerial photography was taken, the height of the vegetation at the time of photography should be noted. When the point is pierced on the top of a feature that is higher than the ground, the ratio of the top to the ground should be noted to 0.1-1, and the value noted should be noted on the back of the film. When the point is pierced on the edge of a feature such as a steep slope, it should be noted on the opposite side of the film whether it is pierced above or below the slope, and the ratio of the slope should be noted. 6.2.5 All control points of the film must be piled or fixed on the spot. 6.3 Decoration of control points of the film
6.3.1 On the front of the control film, triangulation points are represented by regular triangles, buried stone points are represented by squares, film control points are represented by circles, and leveling is represented by centroid symbols. Points that cannot be accurately pierced are decorated with corresponding dotted line symbols, but leveling points are usually decorated with solid line symbols. The reverse length or diameter of the symbol is 7mm. The symbols of leveling points and elevation control points are green, and other symbols and notes are red. On the reverse side of the control film, draw a sketch of the points on the spot to explain the location of the points. The size of the sketch is 2cm×2cm. For the elevation control points of the target products, it is not necessary to draw a map, only to add an explanation. The reverse side of the film shall be decorated with pencil, and the shape and size of the symbols shall be the same as those on the front side. On other control films, only the corresponding symbols with a diameter or side length of 1c shall be used to transfer the control points on the front side, and the point names (battle points) shall be annotated on the adjacent route film. 6.3-2 When the control points of adjacent areas are shared, the control films of the adjacent areas shall be transferred and the sheet number and film number of the actual film shall be added. 6.3.3 The person who punctures, transfers and inspects shall all sign on the reverse side of the film. 6.3.4 The finishing format of the control film is shown in Appendix C. 6.4 Numbering of control points on the film
The numbering of control points on the film shall be specifically specified in the technical design document. 6.5 Plane measurement of photo control points
6.5 1 General rules are
6.5.1.1 The plane coordinates of photo control points are usually determined by electromagnetic wave ranging with wire, branch wire, two-angle lock (linear lock), intersection and lead point, etc. The measurement accuracy should meet the requirements of 3.2. 4. 6.5.1.2 The number of developments of electromagnetic wave ranging with wire, triangulation lock (linear lock) and intersection method. Starting from the triangulation point or advanced terrain control point: no more than three times; when developing with two-angle points or advanced terrain control points continuously, no more than four times. The last control point shall not develop a lead point. 6.5.1.3 The points on the triangular lock (linear lock) and electromagnetic wave ranging attached conductor can develop each other and develop intersection points, but the intersection points cannot be used as the starting and closing points of the two-angle lock (linear lock) and the conductor. 6.5-1.4 When it is difficult, the regression conductor can be used, but the starting point must be checked and confirmed to be correct, and the inspection angle should be measured at the point to be determined. The regression conductor cannot be further developed.
6.5.1.5 When laying attached conductors according to nodes, the route length and number of sides between the node and the starting point can be 0.7 times that in Table 13,
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