Reference no: EM133512222

Question: Address this task to civil design engineers or civil drainage designers only who are well versed in AutoCAD or MicroStation.

Scale of Functional Layout Drawing is approximately 1:380 - I tried to fit the drawing on a 1:500 scale, but unfortunately it does not print the whole layout.

Please find below the requirements for designing the drainage of the Car Park (use either AutoCAD or MicroStation).

There will be no town planning requirements as this is a general car parking training task.

Drainage Requirements:

i. the diameter of pipes placed under pavements must be no less than 375 mm and the height of box culverts must be no less than 300 mm;

ii. all longitudinal, cross drainage and subsurface drainage, including those intercepted by the Works, must be free draining;

iii. culvert end walls greater than 1m high must include a 1.2m fence on top;

iv. new drainage pits must be backfilled around them using at least the applicable pavement design material;

v. subsurface drains installed in expansive materials (swell greater ? 2.5%) must:

vi. not allow the drainage pipes to come into contact with such materials; and

vii. have no less than 100 mm of capping material below the floor of the subsurface drainage trench compacted and graded to design level.

viii. existing subsurface drains that become redundant must be removed to ensure that water is not trapped; and

ix. all new and existing culverts and sub-surface drains must be cleaned and inspected as a condition precedent to Practical Completion.

x. catch drains must be provided at the top of:

1. all cut batters except where drainage is away from the batter; and

2. reinforced earth retaining walls.

xi. subsurface drainage pipes must be Category 1 with a perforation size of a maximum width of 1.5 mm and a minimum opening area of 150 mm per m2.

xii. subsurface drainage beneath trafficable areas must have a no fines concrete backfill filter medium.

xiii. cross drainage and longitudinal stormwater drainage pipes located within any fill must be rubber ring jointed.

xiv. road cross drainage pipes and culverts must be designed such that the top of the drain is > 200 mm below the underside of pavement, except where capping or selected material are required beneath the pavement then the top of drain must be > 200 mm below the underside of capping or selected material.

xv. carpark drainage system must not discharge into the rail corridor or track drainage systems.