Flyboy
11th February 2006, 08:29 PM
Hi all,
Was after some help with a retaining wall we're building. We're using concrete blocks (not exactly sure what they're called) that Concrite make up from their left over concrete. They are 1200x600x600 and weigh about 1 tonne. The wall has to go on a river front, about 800mm high, and the land slopes back from it about 1:3.
Have been to the structural engineer, and he's specified that the design of the wall has to be roughly as per the attachment. My 2 concerns with this are:
1. The wall has the 1200 length of the block at 90 degrees to the river, not parallel as you would, say, in a normal brick wall. This greatly increases the number of blocks required and not sure if the council will allow us to excavate that far back.
2. If we could reduce the depth of the footing to around 400mm, that would allow us to only have 2 rows of blocks instead of 3, also reducing the number of blocks needed.
I think the engineer's main concern is that the tide will wash away the sand from underneath the wall, and that's why he has made the wall so 'hefty'. I was thinking, would a gravel footing under the wall reduce the amount of sand being eroded? If not, would some kind of barrier between the tide and the sand help. I have no idea about seawalls but was thinking if you could sink some FC sheeting into the sand in front of the wall this might stop the sand being washed away. Have to speak to the engineer on Monday, so any other ideas I can fire at him will be greatly appreciated.
Cheers
Was after some help with a retaining wall we're building. We're using concrete blocks (not exactly sure what they're called) that Concrite make up from their left over concrete. They are 1200x600x600 and weigh about 1 tonne. The wall has to go on a river front, about 800mm high, and the land slopes back from it about 1:3.
Have been to the structural engineer, and he's specified that the design of the wall has to be roughly as per the attachment. My 2 concerns with this are:
1. The wall has the 1200 length of the block at 90 degrees to the river, not parallel as you would, say, in a normal brick wall. This greatly increases the number of blocks required and not sure if the council will allow us to excavate that far back.
2. If we could reduce the depth of the footing to around 400mm, that would allow us to only have 2 rows of blocks instead of 3, also reducing the number of blocks needed.
I think the engineer's main concern is that the tide will wash away the sand from underneath the wall, and that's why he has made the wall so 'hefty'. I was thinking, would a gravel footing under the wall reduce the amount of sand being eroded? If not, would some kind of barrier between the tide and the sand help. I have no idea about seawalls but was thinking if you could sink some FC sheeting into the sand in front of the wall this might stop the sand being washed away. Have to speak to the engineer on Monday, so any other ideas I can fire at him will be greatly appreciated.
Cheers