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Summary of calculation formulas and techniques for formwork quantities. I. Explanation 1. For cast-in-place concrete formwork, the quota specifies different types based on various components: modular steel formwork, steel supports, and wooden supports； (This can be used when preparing the base bid price) Composite wooden formwork, steel supports, wooden supports ； (Steel frame + 12mm thick bamboo plywood) Plywood formwork, steel supports, wooden supports ； (Plastic sleeves over tie bolts) Wooden formwork and wooden supports are prepared. 2. Precast concrete formwork is used on site; the quotas are established separately for different components, using combined steel formwork, composite wooden formwork, and wooden formwork, along with corresponding concrete formwork covers, brick formwork covers, and brick formwork cores. 3. The quantities for cast-in-place concrete beams, slabs, columns, and walls are calculated based on a formwork height of 3.6 m (from the ground support point to the bottom or top of the formwork). When the formwork height exceeds 3.6 m, the quantities related to the portion of the formwork that exceeds this height shall be calculated separately. If the formwork height exceeds 3.6 m, the quota items shall be applied starting from above 3.6 m, with one additional application for every additional 3 m. The number of additional ultra-high supports is calculated as (formwork height - 3.6m) / 3; for heights less than 3 meters, it is also counted as 1 time. For every additional 3 meters of super-height, the quantity for beams and slabs is calculated based on the contact area of all the concrete in the super-height components ； Columns and walls are calculated based on the concrete contact area of the super-high portion. II. Rules for calculating the quantity of work 1. For the quantity of work related to cast-in-place concrete and precast reinforced concrete formwork, unless otherwise specified, it shall be calculated based on the area of the contact surface between the concrete and the formwork, in square meters, taking into account the material of the formwork. 2. The reference table for the concrete formwork content in the quota appendix is derived from calculations based on representative projects, and can only be used as a reference when preparing bid prices and base estimates. 3. The volume of formwork for cast-in-place concrete foundations is calculated in accordance with the following rules: (1) For cast-in-place concrete strip foundations, the formwork volume is calculated by multiplying their unfolded height by the length of the foundation, expressed in square meters ； The area of the overlap where the bases intersect is not deducted ； There is also no increase in formwork for the straight foundation ends. (2) The formwork inside the rims of cup-shaped and high-cup foundations shall be included in the quantity of work for the corresponding foundation formwork. For cup-shaped foundations where the height of the cup opening is greater than the length of its longer side, the quota item for high-cup foundations shall be applied. 4. The formwork for cast-in-place concrete columns is calculated in square meters, by multiplying the width around the column by the height of the column. (1) When columns and beams intersect, the area of the column formwork occupied by the beam end is not deducted. (2) When columns and slabs intersect, the area of the column formwork occupied by the slab thickness is not deducted. The quantity of formwork for cast-in-place concrete columns = perimeter of the column cross-section × height of the column. As shown in the diagram, there are 20 cast-in-place concrete frame columns; composite steel formwork and steel supports are used. The quantity of steel formwork needs to be calculated in order to determine the corresponding quota items. http://img.civilcn.com/d/file/zhishi/gczj/2019-09-05/73152e2edaeff086bde8b726d3d6e0d5.png Solution: ① The volume of steel formwork for cast-in-place concrete frame columns = 0.45×4×4.50×20 = 162.00 m2. For rectangular cast-in-place concrete frame columns using combined steel formwork, the quota base price for steel supports of type 10-4-84 is 251.33 yuan per 10 m2. ② The excess height is: 4.5 – 3.6 = 0.90 m, which is approximately 1 unit of excess height. The volume of work related to steel supports for concrete frame columns due to this excess height = 0.45×4×20×(4.50–3.60) = 32.40 m2. Therefore, the total volume of work related to excess height is 32.40×1 = 32.40 m2. When the height of the column support exceeds 3.6 m, for every additional 3 m of excess height, steel supports of type 10-4-102 are used; the quota base price for these is 34.90 yuan per 10 m2. 5. For formwork of structural columns, the area is calculated by multiplying the exposed width of the concrete by the height of the column, in square meters. (1) When the structural columns are connected to the masonry in an interlocking manner, it shall be calculated based on the maximum width of the exposed concrete surface. The formwork area for the contact surface between the structural column and the wall is not calculated. The quantity of formwork for the joint between the structural column and the brick wall = maximum width of the exposed concrete surface × height of the column. (2) The formwork item for structural columns takes into account various types of structural columns as well as the fact that the actual formwork area is larger than the exposed concrete area; it is suitable for cases where the masonry is built first and then formwork is installed followed by concrete pouring for columns located between walls. 6. The formwork for cast-in-place concrete beams (including foundation beams) is calculated in square meters, based on the width of the three sides of the beam multiplied by the length of the beam. Quantity of formwork for cast-in-place concrete beams = (width at the bottom of the beam + height of the side surfaces × 2) × length of the beam. (1) For single beams, the formwork at the supports is not deducted, and no additional formwork is added at the ends. (2) When beams intersect, the formwork area of the main beam occupied by the end of the secondary beam is not deducted. (3) When connecting beams to slabs, the formwork for the beam side walls extends to the bottom surface of the slab. A cast-in-place basket beam, with cast-in-place beam pads at the ends, whose dimensions are shown in Figure 10–7. Wooden formwork, wooden supports; calculate the quantities of formwork and support work for beams, and determine the corresponding quota items. http://img.civilcn.com/d/file/zhishi/gczj/2019-09-05/c2909b935d2e26a87449da233259ff69.jpg ① For beam formwork, the length of the beam cross-section for which formwork is required is 1.627 m. The calculation is as follows: 1.627 * (5.24 – 0.24) + (0.25 + 0.5 * 2) * 0.24 * 2 + 0.60 * 0.20 * 4 = 9.335 m². For irregular-shaped beams, wooden formwork and wooden supports are used; the corresponding code is 10-4-12. The standard price per unit area is 379.76 yuan/10 m². ② For the additional height required for beam supports, the area is still 9.335 m². The number of times the height exceeds the standard value is calculated as: (4.80 – 0.50 – 3.60) ÷ 3.00 ≈ 1 time. For each additional 3 m in height, wooden supports according to code 10-4-13 are used; the standard price per unit area is 73.86 yuan/10 m². 7. For cast-in-place concrete walls, the formwork area is calculated based on the contact area between the concrete and the formwork, expressed in square meters. (1) When connecting walls to columns, the side surface of the column is included in the area of the wall formwork, based on its expanded width. (2) When a wall intersects a beam, the formwork area of the wall occupied by the beam end is not deducted. (3) The tie bolts in the formwork for cast-in-place concrete walls are included in the quota based on their reuse. If required by the project, when the tie bolts (or tie plates) are cast together with the concrete, the provisions in the \"Notes\" of the quota shall be followed ； The end treatment of tie bolts is calculated separately. 8. The formwork for cast-in-place concrete slabs is calculated in square meters, based on the contact area between the concrete and the formwork. (1) The ends of the slabs that extend into beams and walls are not included in the formwork area. (2) For panels with overhanging edges in the surrounding area (such as concrete waterproof strips in bathrooms), the thickness of the base plate is not included in the formwork area ； The formwork on both sides of the overhanging edge is calculated as part of the formwork quantity for the slab, based on the net height of the overhanging edge. (3) When a slab intersects a column, the formwork area of the slab occupied by the column is not deducted. However, when a column is connected to a wall, the formwork area for the part of the column that has the same thickness as the wall (the portion of the column inside the wall) should be deducted. For a cast-in-place reinforced concrete beam-slab structure as shown in the figure, using plywood formwork and steel supports, calculate the quantity of work for the beam-slab formwork and determine the corresponding quota items. http://img.civilcn.com/d/file/zhishi/gczj/2019-09-05/e43d5e9e91a8601109a33f2f21251cbb.png Solution: ① The volume of work for the slab formwork is equal to (2.60×3 – 0.24)×(2.4×3 – 0.24) + (2.4×3 + 0.24)×(0.50 – 0.12)×4 + (2.60×3 + 0.24)×(0.40 – 0.12)×4 = 72.93 m². The formwork uses plywood, with steel supports; according to quota code 10-4-160, the base price is 171.10 yuan per 10 m². ② The additional work required for supporting the slab at greater heights is 72.93 m². The number of times such extra support is needed is calculated as: (5.20 – 0.12 – 3.60) ÷ 3.00 ≈ 1 time. For each additional 3 m of height, steel supports are used according to quota code 10-4-176, with a base price of 31.52 yuan per 10 m². 9. For formwork of cast-in-place concrete ribbed slabs, the calculations are carried out using the same methods as for slabs with beams ； Slanted or folded formwork shall be calculated as flat formwork ； Formwork for precast slabs with joint gaps greater than 40 mm shall be calculated as formwork for flat post-cast joints. When the inclination of various cast-in-place concrete slabs exceeds 15°, the labor cost for the formwork item is multiplied by a factor of 1.30, with all other elements remaining unchanged. 10. For cast-in-place reinforced concrete walls and slabs, holes with a single-hole area of 0.3 m2 or less are not subject to deduction, nor is there any additional requirement for formwork for the side walls of such holes ； When the area of a single opening exceeds 0.3 m2, it should be deducted; the area of the formwork for the side walls of the opening is included in the quantities for wall and slab formwork work. 11. The cast-in-place reinforced concrete frames and frame-shear walls are calculated in accordance with the relevant regulations for beams, slabs, columns, and walls respectively ； Calculation of the workload for integrating wall columns into the wall structure. 12. The sub-item for lightweight frame columns (wall-type columns) incorporates the elements of beams, walls, and columns in lightweight frames, but does not include elevator shaft walls, single beams, or cantilever beams. The quantity for lightweight frame work is calculated based on the exposed area of the frame, in square meters. Quantity of formwork work for lightweight frame = exposed area of the frame. For the coping of cast-in-place concrete cantilever slabs, the quantity of formwork work shall be calculated based on the net height of the coping; sub-item 10-4-211 shall be applied ； If the overhanging height exceeds 300 mm, sub-item 10-4-206 shall be applied. 14. The quantity of work for the secondary formwork of concrete post-cast strips is calculated based on the contact area between the concrete and the formwork, using the relevant items for post-cast strips. The quantity of work for the secondary formwork of the post-cast strip = the contact area between the concrete in the post-cast strip and the formwork. 15. For cast-in-place reinforced concrete cantilever slabs (canopies, balconies), the amount is calculated based on the horizontal projection area of the overhanging portion as shown in the drawings. The corbels and formwork at the edges of slabs outside the wall are not calculated separately. The quantity of work for canopies and balcony formwork = the horizontal projected area of the overhanging portion. 16. For cast-in-place reinforced concrete stairs, the calculation is based on the horizontal projected area of the exposed surface as shown in the drawings; the area occupied by stairwells that are less than 500 mm in size is not deducted. Side formwork for stair treads, tread plates, landing beams, etc., is not calculated separately. The quantity of formwork for concrete stairs = the quantity of reinforced concrete stairs. 17. For concrete steps (excluding treads), the area is calculated based on the horizontal projected area of the step dimensions as shown in the drawings; no additional formwork area needs to be calculated for the sides at the ends of the steps. The volume of formwork for concrete steps = the horizontal projected area of the steps. 18. For cast-in-place concrete small pools and troughs, the volume is calculated based on the outer perimeter of the structure; formwork for the inside, outside, and bottom of such pools and troughs is not counted separately. Quantity of formwork work for small cast-in-place concrete tanks = volume around the perimeter of the tanks, 19. Excessive height of formwork support for cast-in-place concrete columns, beams, walls, and slabs: (1) The quota for formwork support of cast-in-place concrete columns, beams, walls, and slabs is formulated based on a formwork height of 3.60 m. When the formwork height exceeds 3.60 m, the corresponding sub-item for \"every additional 3 m\" shall be applied (if it is less than 3 m, it shall be calculated as 3 m) to determine the extra cost for formwork support at higher heights. (2) For structural columns, ring beams, and walls made with large steel formwork, the extra height due to formwork support is not taken into account. (3) Formwork height for columns and walls: from the floor (floor level) support point to the top surface of the component ； Liang: From the floor (floor slab) support point to the bottom of the beam ； Slab: From the floor (floor) support point to the bottom surface of the slab. (4) The volume of work for template support due to excess height in beams and slabs (horizontal elements) is calculated as follows: Number of excess height increments = (Height of template support – 3.6) ÷ 3; if the result is a decimal, it is rounded up to 1. Volume of work for excess height (in m2) = Total template area of the element with excess height × Number of excess height increments. (5) The volume of work for template support due to excess height in columns and walls (vertical elements) is calculated as follows: The number of excess height increments is determined in segments; starting from 3.60 m, the first 3 m represent one increment of excess height, the next 3 m represent a second increment, and so on ； If it is less than 3m, it shall be calculated as 3m. The volume for excessive height (m2) = ∑(area of corresponding formwork × number of times of excessive height) (6) The formwork support required for the rear pouring joints in walls and slabs is included in the volume calculation for the formwork support related to the excessive height of those walls and slabs. 2. The quantity of formwork for on-site precast concrete components shall be calculated in accordance with the following provisions: (1) Unless otherwise specified, the quantity of formwork for on-site precast concrete is calculated in cubic meters based on the actual volume of the concrete. The volume of precast concrete formwork works on site = the volume of concrete work (2). Precast piles are calculated based on their volume, without deducting the volume of the tip portion of the piles. The volume of formwork for precast piles = 3 × the volume of concrete. 3. The volume of formwork for concrete in structures is calculated as follows: (1) For structures such as water towers, water (oil) storage tanks, and storage silos, the volume of formwork is determined based on the contact area between the concrete and the formwork, measured in square meters. (2) Large tanks and similar structures are calculated in accordance with the relevant regulations for foundations, walls, slabs, beams, columns, etc., and the corresponding quota items are applied. (3) For chimneys, inverted conical shell water tower sleeves, water tanks, silos, etc. constructed using hydraulic sliding formwork, the volume is calculated based on the concrete volume, in cubic meters. (4) The lifting of water tanks in inverted conical shell water towers is calculated per seat based on different volumes.