Earthwork engineering is a kind of civil engineering, with a wide area, large amount, heavy labor, complex construction conditions and other characteristics, common earthwork engineering are: site leveling, regional balance, foundation pit (groove) and pipe trench excavation, roadbed excavation, civil air defense engineering excavation, floor filling, roadbed filling and foundation pit backfilling.
The calculation of earthwork quantity is regarded as the most complex quantity calculation except for steel structure quantity. The reason why earthwork quantities are so complex is that different earthworks have different calculation rules, now, let's take a look at the following calculation rules for earthworks:
1. Calculation of earthwork quantity:
1. The volume of earthwork is calculated based on the volume of natural dense solids before excavation. If it is necessary to convert the natural dense solid volume, it can be converted according to the values listed in the table below.
Earthwork volume conversion table
2. The excavation of the building shall be calculated based on the elevation of the designed outdoor floor.
2. The amount of leveling site and rolling work shall be calculated according to the following provisions:
1. Artificial leveling refers to the excavation, filling and leveling of the construction site within ±30cm. When the thickness of excavation and filling exceeds ±30cm, it shall be calculated separately according to the vertical layout of the earthwork balance of the site.
2. The amount of leveling site is calculated in square meters according to the addition of 2m on each side of the outer edge line of the outer wall of the building.
3. The original soil rolling of the construction site is calculated in square meters, and the filling thickness is calculated in cubic meters according to the filling thickness shown in the figure.
The key basis for judgment: to see whether the height of the excavation and the depth of the filling exceed (>;h or =)300mm.
3. The amount of earthwork excavated trenches and foundation pits shall be calculated according to the following provisions:
1. When digging trenches and foundation pits to support the retaining plate, the width of the trench and foundation pit is shown in the figure, and 10cm is added on each side. The area of the retaining plate is calculated according to the vertical support area of the groove and pit. The double-sided support is also calculated according to the vertical area of one side, and the quota of the double-sided retaining plate is applied, and the quota is implemented regardless of continuous or intermittent. Where the grading part shall not be calculated retaining plate, after supporting the retaining plate, shall not be calculated again.
2. The working face required for foundation construction shall be calculated as specified in the following table.
Calculation table of the working face width required for foundation construction
3. The length of the trench is calculated according to the length of the center line shown in the figure, and the length of the net length between the bottom surface of the foundation shown in the figure is calculated for the inner wall: the volume of the inner and outer protruding parts (stacks, chimneys attached to the wall, etc.) is calculated in the earthwork quantity of the trench. The excavation of the foundation pit earthwork is calculated according to the size shown in the figure.
4. The depth of the trench and foundation pit shall be calculated according to the depth of the groove and the bottom surface of the pit to the outdoor floor shown in the figure, and the depth of the pipeline trench shall be calculated from the bottom of the trench to the outdoor floor shown in the figure.
Fourth, the calculation of the amount of earthwork excavated into a groove for the underground diaphragm wall
According to the design length, width and groove depth of the diaphragm wall (plus super depth of 0.5m) are calculated in cubic meters.
5. The amount of rock excavation and blasting work, and the difference between stone quality shall be calculated according to the following provisions:
1. Artificial rock drilling, calculated in cubic meters according to the size shown in the figure.
2. The blasted rock is calculated in cubic meters according to the size shown in the figure, and the allowable over-excavation amount of the trench, foundation pit depth and width is 200mm, and the over-excavated part of the rock is incorporated into the rock excavation amount to calculate.
6. Calculation of mechanical removal of concrete obstacles
Calculated in cubic meters based on the volume of the dismantled component.
7. Calculation of manually chiseled reinforced concrete pile head
It is calculated in cubic meters by multiplying the cross-sectional area of the pile by the length of the head of the pile being chiseled.
8. The backfill is divided into rammed and loose fills in accordance with the following provisions, calculated in cubic meters:
1. Trench and foundation pit backfill, and the volume of trench and foundation pit backfill is calculated by subtracting the volume of buried masonry (including: foundation cushion, foundation, etc.) below the design outdoor floor.
2. The backfill of the pipeline trench is calculated by subtracting the volume of the pipe diameter from the volume of the cutout. If the pipe diameter is less than 500mm, the volume occupied by the pipeline will not be deducted, and when the pipe diameter is more than 500mm, the volume occupied by the pipeline shall be deducted according to the regulations.
3. Indoor backfill is calculated by multiplying the area between the main walls by the thickness of the backfill.
4. The amount of residual soil or soil extraction can be calculated as follows:
Remaining soil transport volume = total volume of excavated soil - total volume of backfill soil (or calculated according to the construction organization design)
In the formula, when the calculation result is a positive value, it is the volume of the remaining soil, and when it is negative, it is the volume of the soil to be taken.
9. The earthwork distance shall be calculated according to the following provisions:
1. Bulldozer bulldozer distance: calculated according to the straight-line distance between the center of gravity of the excavation area and the center of gravity of the backfill area.
2. The distance of the scraper to transport the earth: calculated according to the center of gravity of the excavation area to the center of gravity of the unloading area plus the steering distance of 45m.
3. Dump truck earth transportation distance: calculated according to the shortest distance from the center of gravity of the excavation area to the center of gravity of the filling area (or stacking site).
10. Calculation of fences, retaining walls, wells, septic tanks, etc
Not counting the leveling aspects of it.
11. Calculation of substrate brazing
The base area is calculated in square meters according to the diagram shown.
After reading the above eleven earthwork quantity calculation rules, do you think it is very complicated! In addition to the above rules, what other ways do we have to quickly calculate?
With the development of BIM technology, in recent years, earthwork has abandoned the traditional calculation method and used BIM software OpenRoads Designer for fast calculation:
Firstly, a 3D excavation and filling earthwork model is created as a digital twin model to visually reflect the current situation of the earthwork project, and then BIM software is used to accurately calculate the earthwork quantity, and finally the excavation and filling amount is summarized and analyzed.
The use of BIM software to calculate the quantity of earthwork can not only simplify the calculation steps of the quantity, but also analyze the earthwork project through the digital twin model of earthwork and formulate the later construction plan.