Driveway using retaining wall to level - Proposed plans

[martin55]

Hi,

 

I have a sloped front unused garden that I'm planning to convert to a driveway. The drop kerb has been approved.

 

However I would like someone in this field of landscaping/construction to check my plans. I'm not going to hold anyone to their word, I am new to this and I want to know what someone would usually do.

 

Link: https://ibb.co/P6LGLM4

 

My main concern currently is the footing requirements, as that's the first step. Basic stats from the link:

- length 5.7m x width 2.7m

- Using hollow concrete blocks 415mm x 215mm x 215mm

- Footings 280mm depth x 330 width

- Using 12mm rebar in the footings to line up with holes in hollow bricks, which I'll then fill with concrete

 

I'm confident in making the wall itself, but not sure about footings (most important part I think).

 

Thanks.

Edited September 5, 2022 by martin55

[markc]

The footings sound more than sufficient, the key here is the slope and what it consists of. If you have a smooth slope and simply fill it, you then end up with one wedge on the top of another putting a large side load on your retaining wall. I am presuming you will infill with old bricks/rubble etc. chew up the surface of the slope, cutting terraces is better but at least dig some small holes or indentations, this Allows the fill to get hold of the slope and resist its tendency to move downwards, also don’t forget your weep holes at the bottom of the retaining wall to allow water to escape

Edited September 5, 2022 by markc

[martin55]

12 minutes ago, markc said:

The footings sound more than sufficient, the key here is the slope and what it consists of. If you have a smooth slope and simply fill it, you then end up with one wedge on the top of another putting a large side load on your retaining wall. I am presuming you will infill with old bricks/rubble etc. chew up the surface of the slope, cutting terraces is better but at least dig some small holes or indentations, this Allows the fill to get hold of the slope and resist its tendency to move downwards, also don’t forget your weep holes at the bottom of the retaining wall to allow water to escape

Thanks a lot, I hadn't thought of that.  And yes I will do terraces as it isn't much more work. 

 

Can I ask what your background is. Such as experience?

 

Thanks again.

[markc]

57 minutes ago, martin55 said:

Thanks a lot, I hadn't thought of that.  And yes I will do terraces as it isn't much more work. 

 

Can I ask what your background is. Such as experience?

 

Thanks again.

My experience omg! Been mixing and Laying concrete since I was about 8, built a two story timber frame building when I was 15 (with a 17 yr old labourer) since then I put up loads of steel and glulam buildings and then construction engineer/manager on bridges, football stadiums, underpinning, mining and and and …

Edited September 5, 2022 by markc

[martin55]

1 hour ago, markc said:

My experience omg! Been mixing and Laying concrete since I was about 8, built a two story timber frame building when I was 15 (with a 17 yr old labourer) since then I put up loads of steel and glulam buildings and then construction engineer/manager on bridges, football stadiums, underpinning, mining and and and …

Thanks a lot. I appreciate your time and experience to help me out. 

The weep holes, I'm not familiar but just done some reading up. From what I see, I can either leave gap between a couple (not sure how many is required) of the concrete hollow blocks where there would usually be cement, or use a plastic pipe insert. Assuming on the last course of bricks, and also likely at the end of the training wall where it's highest as water will run down hill.

Edited September 5, 2022 by martin55

[markc]

Weep holes just allow any trapped water behind the wall to escape, as you are using blocks a small (plastic conduit or even 15mm plumbing hep20/etc. is ok) spaced about 2m apart. Put foundations in, first layer of blocks, weep pipes,build rest of wall, pebbles or gravel at bottom behind wall for drainage and to stop weep pipes from blocking up) dpm up inside face of wall and then backfill compacting layers as you go

[Roger440]

deleted. didnt read your post properly.

Edited September 6, 2022 by Roger440