Assumption list | 1. Assume * The thickness of topsoil is 150mm. | * pagepaax is all the same length which is exceeding 500mm thick. | * The designed concrete is grade C25, * Cement to BS12, * 20mm aggregate to BS882, * Minimum cement contact 120kg/m3 |

Red line indicates the contour line.
Blue line indicates the area of retaining wall.
Yellow indicates the area to be fill.
Green indicates the area to be cut.
Cutting

Point | Ground level | Depth of cut (x) | weighting (y) | xy | 4B | 99.80 | 0.150 | 1 | 0.150 | 5B | 100.38 | 0.380 | 2 | 0.760 | 5C | 100.48 | 0.480 | 4 | 1.920 | 5D | 100.35 | 0.350 | 4 | 1.400 | 5E | 100.20 | 0.200 | 4 | 0.800 | 5F | 100.00 | 0.150 | 3 | 0.450 | 6B | 102.10 | 2.100 | 2 | 4.200 | 6C | 101.96 | 1.960 | 4 | 7.840 | 6D | 101.95 | 1.950 | 4 | 7.800 | 6E | 101.80 | 1.800 | 4 | 7.200 | 6F | 101.50 | 1.500 | 4 | 6.000 | 6G | 101.03 | 1.030 | 4 | 4.120 | 6H | 100.80 | 0.800 | 1 | 0.800 | 7B | 105.09 | 5.090 | 2 | 10.180 | 7C | 106.00 | 6.000 | 4 | 24.000 | 7D | 106.03 | 6.030 | 4 | 24.120 | 7E | 106.05 | 6.050 | 4 | 24.200 | 7F | 104.02 | 4.020 | 4 | 16.080 | 7G | 103.00 | 3.000 | 4 | 12.000 | 7H | 101.8 | 1.800 | 2 | 3.600 | TOTAL | | | 65 | 157.620 |

Average depth of cut = 157.62/65 = 2.425
Average depth of cut excluding topsoil = 2.425 - 0.15 = 2.275

Filling

Point | Ground level | depth of fill (x) | weighting (y) | xy | 3B | 97.78 | 2.220 | 1 | 2.220 | 3C | 97.90 | 2.100 | 2 | 4.200 | 3D | 97.80 | 2.200 | 2 | 4.400 | 3E | 97.60 | 2.400 | 2 | 4.800 | 3F | 97.30 | 2.700 | 2 | 5.400 | 3G | 96.94 | 3.060 | 2 | 6.120 | 3H | 95.75 | 4.250 | 1 | 4.250 | 4B | 99.80 | 0.200 | 1 | 0.200 | 4C | 99.50 | 0.500 | 4 | 2.000 | 4D | 99.40 | 0.600 | 4 | 2.400 | 4E | 98.95 | 1.050 | 4 | 4.200 | 4F | 98.75 | 1.250 | 4 | 5.000 | 4G | 98.30 | 1.700 | 4 | 6.800 | 4H | 98.10 | 1.900 | 2 | 3.800 | 5F | 100.00 | 0 | 3 | 0 | 5G | 99.00 | 1.000 | 4 | 4.000 | 5H | 99.50 | 0.500 | 2 | 1.000 | 6H | 100.80 | 0 | 1 | 0 | TOTAL | | | 45 | 60.790 |

Average depth of fill = 60.79/45=1.351
Average depth of fill include topsoil= 1.351+ 0.15 = 1.501

T | D | S | | | Description | | | | | | | | | | | | | | Retaining wall excavation | | 30.00 | | General excavation, maximum depth 0.5-1m (E423) | | 2.50 | | | | | | | | 0.80 | | | | | | | | | | Disposal of excavated soil | | | | Excavation ancillaries, disposal of excavated material (E532) | | | | Provision of concrete | | 30.00 | | | | | | | | 2.50 | | Designed concrete grade C25, cement to BS12, 20mm | | 0.80 | | aggregate to BS 882, min cement contact 120kg/m3 | | | | | | | | | | 30.00 | | | | | | | | 1.80 | | | | | | | | x | | | | | | | | | | | | | | | | 30.00 | | | | | | | | 1.20 | | | | | | | | x | | | | | | | | | | | | | | | | 30.00 | | | | | | | | 0.60 | | | | | | | | x | | | | | | | | | | Placing of concrete | | 30.00 | | | | | | | | 2.50 | | Mass bases, thickness exceeding 500mm (F624) | | 0.80 | | | | | | | | | | | | | | | | 30.00 | | | | | | | | 1.80 | | | | | | | | x | | | | | | | | | | | | | | | | 30.00 | | | | | | | | 1.20 | | Mass walls, thickness exceeding 500mm (F644) | | x | | | | | | | | | | | | | | | | 30.00 | | | | | | | | 0.60 | | | | | | | | x | | | | | | | | | | | | | | | | | | Formwork | | 30.00 | | | | | | | | 2.50 | | Rough finish, horizontal (G115) | | | | | | | | | | 2/ | 30.00 | | | | | | | | 0.80 | | | | | | | | | | Rough finish, vertical (G144) | | | | 30.00 | | | | | | | | x | | | | | | | | | | | | | | | 3/ | 30.00 | | Fair finish, horizontal (G214) | | | | 0.60 | | | | | | | | | | | | | | | 2/ | 30.00 | | | | | | | | x | | | | | | | | | | Fair finish, vertical (G244) | | | | 30.00 | | | | | | | | 3x | | | | | | |