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View Full Version : Establishing grade for a SRW


JDeere
06-11-2009, 12:52 AM
Guys this is a design and esthetics question. I have to put in a 180' SRW. 80' runs about 30" above grade; the next 100' runs around 36" to 42" above grade. The foreground in front of the wall is flat relating to a cutout for a large shop. The slope behind the retaining wall rises gently about 18" in the first ten feet. I could make this a little more dramatic by dropping the wall height to display plantings better. Beyond ten feet back of the wall it is relatively level. Footing is clay. The wall follows the road down a mild decline to the new shop location. This comes to my question. The first 40' of the wall slopes down about a 4% grade, or about 5" of slope every 10'. The rest of the wall follows a 2% left-to-right slope of 2%, or about 2.5" every ten feet.

Question !: What do you think would look better a) establishing the wall with a laser level so that every row of block is about dead level, or b) establishing wall grade to let the blocks follow the natural grade contour, which is pretty gentle except for the first 40' of 4% grade?

Choice a) will result result in stepping the wall frequently.

Question 2: The wall footing has not yet been excavated. Presently final grade for the road approach to the shop has been established. My thought was to excavate for the wall footing only another 8" below the road sub-grade. Before you jump on me, the 8" cut would be filled level with 3/4-minus and compacted for wall footing. This would bring the first row of block up high enough to be dead level with the newly established road sub-grade. Once the wall is constructed, a 6" lift of 3/4-minus would go down and be compacted prior to asphalt. This would bury the first row of block. The asphalt would further bury the first row of block, also locking it in place. I would probably compact the rock immediately in front of the wall with a jj just to ensure it is ultra tight. Does this sound reasonable?