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Road No 2
Road No 1
Road No 1
Road No 1
Public Drain
Public Drain
Outlet point C
Connection to
Public drain
(Invert level = 100.0mRL)
A
B
C
D
E
F
G
H
Assignment 2 (15%):
Design a concrete drainage system to serve the land parcel ABCD for a HDB estate
You are given a piece of land ABCD such that the distance AB is 1500m while the distance AD is 1000m.
Note that AE = FB = 745m and AG = HD = 445m
There are two roads running longitudinally (Road No 2) and transversely (Road No 1) within ABCD.
You may assume the average velocity of the water in all drains to be 0.8m
You are required to design a drainage system consisting of a series of drains to run parallel to Road No 1. and Road No. 2.
The water within ABCD is suppose to finally flow to outlet point C (with an invert level of 100.0mRL) as indicated in the figure.
For simplicity, you can assume the ground level of your land parcel ABCD to be perfectly flat with a formation level of 104.0mRL
You can
eak down the assignment into small parts and submit them to me individually
Assignment 2:
Upon completion of your drainage system design, you must indicate on the figure the following:
Location of your drains (use red color to draw the lines on the figure)
Location of summit points (label your summit points S1, S2 S3 etc) and indicate the invert level of all your summit points
on the figure
Indicate the invert level of the drains at all intersection points.
(Where the drains cross the roads, it will be in a series of rectangular culverts and you do not need to design them,
you can assume any suitable sizes and just indicate as hidden lines)
d. Show the direction of flow of the water in your drainage system.
Indicate the gradient of your drains
Shape and size of your drain.
Produce separate drawings showing the catchments of your drains.
Calculations to determine the peak flows and calculations to justify the size of the drains you are using.