rubble retaining wall quantity calculation

A rubble masonry retaining wall is a type of construction that employs unshaped, natural stones of varying sizes and shapes to create a wall. This imparts a rugged and irregular appearance to the structure. These stones are bound together using mortar, which fills the gaps between them.

Throughout history, rubble masonry walls have been a prevalent choice in ancient and traditional building practices, particularly in areas lacking easily accessible, finely cut stones. They bestow a charmingly rustic and organic look and can be observed in a multitude of historical edifices worldwide.

3D retaing wall

Retaining wall section

retaining wall section

Given,

wall length = 10000mm

wall base width = 1800mm

wall top width = 500mm

wall height = 4500mm

depth below ground level = 500mm

Mortar ratio = 1:6 (cement : sand)

pcc mix ratio = 1:4:8 (cement : sand : aggregate)

pcc thickness = 100mm

pcc offset = 100mm

Quantity Calculation

Pcc

Length = 10000mm = 10m

width = 1800+100+100 = 2000mm = 2m

pcc thickness = 100mm = 0.1m

wet volume = (10*2*0.1) = 2m^3

we have to convert wet volume into dry volume by multiplying 1.54

Dry volume = 1.54*2 = 3.08m^3

sum of ratios = 1+4+8 = 13

Volume of Materials

volume of cement = (1/13)*3.08 = 0.2369 ~ 0.237m^3

volume of sand = (4/13)*3.08 = 0.948m^3

volume of aggregate = (8/13)*3.08 = 1.895m^3

To calculate weight of cement, we will use mass=density*volume

density of cement = 1440kg/m^3

weight of cement = 1440*0.237= 341.3 Kg

To buy the cement in market we have to buy in bags

1 bag of cement = 50 Kg

No. of cement bags required = 341.3/50 = 6.826 ~ 7 bags

In the market, we can buy sand and aggregate in cft unit, To convert m^3 to we have to multiply by 35.32

volume of sand = 0.948*35.32 = 33.484 cft

volume of aggregate = 1.895*35.32 = 66.932 cft

Material Quantity in Retaining Wall

since, the wall is of trapezium shape, to calculate volume we can multiply length by area of wall

Area of wall = 0.5(0.5+1.8)*4.5 = 5.175m^2

volume of wall = 5.175*10 = 51.75m^3

To calculate the volume of stone we have to multiply wall volume by 1.25 as stone volume will be 125% of wall volume

Stone volume = 51.75*1.25 = 64.688m^3

To calculate the volume of mortar we have to multiply wall volume by 0.4 as mortar volume will be 40% of wall volume

Mortar volume = 0.4*51.75 = 20.7m^3

To get dry volume we have to multiply wet volume by 1.33

Dry volume = 1.33*20.7 = 27.531m^3

sum of ratio = 1+6 = 7

Cement volume = (1/7)*27.531 = 3.933m^3

Sand volume = (6/7)*27.531 = 23.598m^3

No. of cement bags required = 3.933*(1440/50) = 113 bags

Sand Quantity Required = 23.598*35.32 = 833.481cft

Quantity Table

Sl. No.ParticularsCement (bags)Sand (cft)Aggregate (cft)Stone (m^3)
1.PCC733.48466.932
2.Retaining Wall113833.48164.688
Total120866.96566.39264.688

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top