Diagram Details & Dimensions
- EDGE OF ROAD OR DRIVEWAY
- 3' MIN. OR "H" WHICHEVER IS GREATER (Setback Distance)
- POST LARGER DIMENSION (Alignment reference)
- 4" MIN. (Height above slope)
- 2:1 UNLIMITED (Slope above wall)
- POST (Vertical support member)
- 12" (Gravel drainage layer width)
- PLANKS (TYP.) (LAGGING)
- WRAP WITH GEOTEXTILE FABRIC
- 1/4" GAP (TYP.) (Between planks)
- 4" PERF. PIPE SCHEDULE 40 PVC, (OR ALTERNATIVE BACKDRAIN) AS REQUIRED BY AGENCY ENGINEER. PROVIDE OUTLET. WRAP PIPE WITH GEOTEXTILE FABRIC
- 5' MIN. (Bench width at grade)
- 2% (Slope for surface drainage)
- FINISHED GRADE
- CONCRETE (Post support, see Note 5)
- 3/4" CRUSHED ROCK (Drainage backfill)
- 2" WEEP HOLE @ 8' O.C. (UNLESS PIPE USED)
- 18" (Diameter of post support footing)
- 6" (Footing offset)
- "H" (Wall height above grade)
- "D" (Post embedment depth)
| H | D | POST SPACING | POST SIZE |
|---|---|---|---|
| 2' | 3.5' | 4' | 4"x4" |
| 3' | 5' | 4' | 4"x6" |
| 4' | 6' | 4' | 4"x6" |
GENERAL NOTES:
- LUMBER SHALL BE ROUGH DOUGLAS FIR No. 1 PRESSURE TREATED, AS APPROVED BY THE ENGINEER.
- PRESSURE TREATMENT SHALL MEET THE FOLLOWING: 0.40 pcf ACQ & CCA-C, 0.41 pcf CBA-A, 0.21 pcf CA-B.
- NAILS/METAL FASTENERS SHALL BE HIGH QUALITY CLASS G-185 HOT DIPPED GALVANIZED (ASTM A153 OR A653), 304 OR 316 STAINLESS STEEL, OR OTHER ACCEPTABLE CORROSION RESISTANT MATERIAL.
- ALL CUTS, HOLES AND INJURIES (SUCH AS ABRASIONS AND NAIL HOLES) SHALL BE FIELD TREATED WITH APPLICATIONS OF PRESERVATIVES IN ACCORDANCE WITH AWPA STANDARD M4.
- CONCRETE FOR POST SUPPORT SHALL BE CLASS C (4 SACK MIX) WITH 1" MAX. AGGREGATE.
6._