curved retaining wall 1

[markotarko2000]

Hello all,

I have a retaining wall going beside a curved road, the wall length is 24meters, I want to understand if it's applicable to design the wall curved or it might be composed of three straight walls connected ?
also i want to undersnand, how I will devide the retaining wall? to three 8 meters parts or to two 12.5 meters parts?

 

[ishvaaag]

You may design it curved if so wanted. I would check for bigger push than ordinarily considered (active wedge) if concave from the road and taking an important slope focused more or less on its center. I would model the entire thing 3D in any case where significant 3D action is expected and wanted be identified for reinforcement optimization (certainly, almost never in basements of buildings).

Depending on the case you may choose to go by straight segments. At some times the end segments can be thought more than anything as reaction or abutment walls, but for whatever the shape you can identify the relevant parameters for design by an analysis in 3D.

 

[apsix]

The fact that you are considering 2 x 12 metre straight lengths implies a large radius curve.

I would design it as a typical straight wall. Some thought will be required re joint spacing & locations, and horizontal reinforcement.

The decision regarding straight or curved is dependent on construction.
It you are looking at Cast-In-Place concrete a curved wall is unlikely to be cost effective due to formwork requirements.
A filled concrete block or segmental wall can be easily built to a curve.

Will other stakeholders have any input on aesthetics, eg. client, architect, local authority?

Finally, without knowing the layout of the road and proposed wall it is not possible to give advice regarding length of wall segments.

 

[JoshPlumSE]

I disagree somewhat with Ishvaag's comments about cost. If you're using a concrete block wall (i.e. Masonry), then I wouldn't think that a curved wall would be significantly more expensive than a straight one.

I would normally design the wall as a cantilever wall. I just don't seen modeling in the curved geometry as being something signficant enough to be worth all the extra design effort.

If I'm concerned that additional stressed might arise, then I coul throw in an expansion joint to reduce shrinkage cracks and force the wall to behave closer to what I assumed.

 

[csd72]

The deepest part of the failure wedge will be down near the wall and proportianate to the wall length itself. The areas of the failure wedge that are most widened by the curve are also the shallowest.

I would think that this would make much less difference than you think and would be covered adequately with a straight wall analysis and a small contingency (say 10%) for the curve.

I did a reinforcement of an old curved brick retaining wall recently. The retaining wall was on the outside of a curved ramp and had started to rotate. The wall on the inside of the curve was perfectly vertical with no problems even though it was identical construction and backfill. Why? Myself and a more senior engineer agreed that it must be at least partly due to the arching action horizontally along the curve.