How to calculate volume of quandrilateral / Irregular shape concrete?

Place bricks on one top of the other around the concrete shape you want to find its volume. First, choose a rectangular shape around the object and then going to the object. Then place a sufficiently large sheet of polythene in the space around the concrete object for covering the mold. Then take a standard bucket of 25-liter capacity and then slightly pour water within the polythene most do formed. Keep a count of the buckets of water poured till it overflows at the top of the brick wall. Measure the inside dimension and depth of the rectangular moat.

Consider them as two triangles jointed.

Calculate the volume of each triangle prism and then make the addition.

It gives an accurate result.

Volume of triangular prism= 0.5 * b* h * l

b= base

h= height

l = slant height.

Here a prism with triangular areas are given. Yours is quadrilateral areas. Hence Sb1 and Sb2 will be area of quadrilaterals

Now to find area of quadrilaterals, you need more measurement - either one diagonal or two angles.

If you know diagonal, then use the below link to find the area using diagonal

https://www.vcalc.com/wiki/vCalc/Quadrilateral+Area+(with+diagonal)

If you know the angles, then use the below link to find the area using diagonal

https://www.vcalc.com/wiki/vCalc/Quadrilateral+-+area

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