Guidelines for measuring reinforced concrete works such as foundations, columns, beams, slabs, and pedestals are essential for determining the actual cost of construction and facilitating payment to contractors. The measurement process involves calculating the quantities of various reinforced concrete works using specific formulas. By following these guidelines, accurate measurements can be obtained, which ensures that contractors are compensated appropriately for their work.
Measurement of Reinforced Concrete Works:
The measurements for quantities can be rounded off to the nearest two decimal points. When measuring concrete in structural members like columns, beams, and slabs, each one must be measured separately. Deductions cannot be made for certain things, such as openings up to 0.1 square meters, the volume occupied by reinforcement, and the volume occupied by pipes, conduits, and sheathing that do not exceed 100 square centimeters each in cross-section. Additionally, there are certain structural features that can be disregarded when making deductions, such as moulds, drips moulding, chamfers, splays, rounded or covered angles, beds, grooves, and rebates that do not exceed 10 centimeters in girth. These rules and guidelines must be followed when measuring and deducting quantities in structural construction.
Measurement of Concrete in Footings:
The volume of concrete for a rectangular or square footing is calculated by multiplying the length, width, and depth of the footing. However, for a trapezoidal footing, the volume of concrete is calculated in two parts. The bottom rectangular portion is calculated separately, and the trapezoidal volume is calculated separately.
To calculate the rectangular volume, we use the formula length times width times depth. For the trapezoidal volume, we use a different formula. We first calculate the area of the top and bottom rectangles, which we denote as A1 and A2, respectively. Then, we multiply the depth of the footing, which we denote as H, by the sum of A1 and A2 and the square root of the product of A1 and A2. Finally, we divide this result by 3. This gives us the trapezoidal volume.
To get the total volume of concrete for a trapezoidal footing, we add the rectangular volume to the trapezoidal volume.
Measurement of Concrete in Columns
When measuring columns, the starting point should be from the top of the column base to the underside of the first floor slab. For subsequent measurements, the column should be measured from the top of the floor slab to the underside of the floor slab above. It is important to note that in the case of columns for flat slabs, the flare of the column should also be included in the measurement process. This means that when measuring columns for flat slabs, the flare of the column should be considered as part of the column for measurement purposes. By following these guidelines, accurate measurements can be taken to ensure that the columns are constructed to the correct specifications.
Measurement of Concrete in Pedestals
When measuring beams, it is important to take into account the distance between the faces of the columns that support them. This measurement should also include any haunches that may exist between the columns and beams. The depth of the beams should be measured from the bottom of the slab to the bottom of the beam, unless the beam is an inverted one. In the case of an inverted beam, the depth measurement should be taken from the top of the slab to the top of the beam. It is important to follow these measurement guidelines to ensure accuracy in construction and to avoid any potential issues down the line.