**Calculation of reinforcement for construction/building project**

The calculation of reinforcement for construction/building project project is a vital assignment as it enable the client to know beforehand the expenditure on reinforcement in the case of a building and the contractor in the case of large project.

Knowing the quantity of reinforcement to be used for a particular project is an important task to be carried out by the engineer/contractor to enable billing and quantification of material. This article explains the simplest way of doing this calculation. It can also be used to calculate the quant of reinforcement bar consumes by ironworkers for payment.

**The unit weight of reinforcement bar**

For us to carried out the calculation of the reinforcement bar, we must first know the unite weight of the reinforcement or steel bar. This calculation is carried out using the formula below

Unit weight of steel
bar = D^{2}/162.28kg/m where D is the diameter of the steel been
considered.

Considering 12mm steel bar, the unit weight of 12mm steel bar per meter will be thus:

Unit weight = 12^{2}/162.28
= 0.8873551886 ~ 0.887kg/m

The standard length of the reinforcement bar is 12m. therefore, to know the unit weight of the 12meters 12mm bar, multiply the length (12m) by the unit weight to get the weight of the steel bar since steel is measured in weight (kg or tone). Hence, the unit weight of 12mm of 12meter length is = 0.887 x 12 = 10.46kg

Therefore, the unit weight of 12mm rod of 12meter length is 10.46kg.

Again, let us consider a steel bar of 20mm and 25mm of length 12meters

Applying the formula
above, unit weight of 20mm steel bar is = D^{2}/162.28kg/m = 20^{2}/162.28
= 2.4648755238 ~ 2.465kg/m and that of 25mm steel bar is = D^{2}/162.28kg/m
= 25^{2}/162.28 = 3.8513680059 ~ 3.851kg/m

Therefore, the unit weight of 20mm steel bar of 12metere = 2.465 x 12 = 29.58kg and that of 25mm steel bar of 12meters = 46.212kg

**How many pieces of 12mm, 20mm and 25mm rods of length 12m are in one tone**

To get the number of 12mm, 20mm and 25mm of 12m in one tone, divide one tone by the unit weight of 12m length of each of them. See the procedure below

The unit weight of 12m length of 12mm, 20mm and 25mm are 10.46kg, 29.58kg and 46.212kg respectively.

But one tone is = 1000kg therefore, for 12mm rod, one tone will contain thus: 1000/10.46 = 95.60 ~ 96 pieces of 12mm make up one tone of 12mm rod

Also, for 20mm rod, one tone will contain thus: 1000/29.58 = 33.80 ~ 34 pieces of 20mm rods make up one tone of 20mm. applying the same to 25mm, one tone of 25mm will contain thus: 1000/46.212 = 21.63 ~ 22 pieces of 25mm are there in one tone of 25mm rod.

This, therefore, shows that the higher the diameter of the steel bar, the lesser the quantity in a tone. For your building and other civil engineering projects, contact us at +2347034333017, euniquetech101@gmail.com. Also, visit our website at www.euniquetech.com