A pebble and stone concrete wall differs from a normal concrete wall in that the concrete mixture consists of decorative pebbles and stones rather than gravel, and the pebbles and stones are exposed on the surface of the concrete rather than being hidden beneath the surface like regular concrete gravel. The average do-it-yourself homeowner can build a pebble and stone concrete wall in one to two days, depending on the size and scope of the project.
Form the concrete wall to desired thickness. You may choose any thickness between 8- and 16-inches; however, the most common thickness is 8-inches. Using 2-by-4 lumber and 3/4-inch plywood, build panels that are 8 feet long--length of plywood--and 32-to 48-inches high. Depending on the length of your wall, you may need to build several of these panels.
Stand the panels on their sides--32-to 48-inches up--with the framing to the outside of the proposed wall--and brace them with scrap 2-by-4s. Use a nylon string to ensure that the panels are straight. Assemble another line of panels on the opposite side of the previous panels, and measure the distance between the two. The area between the two sets of panels represents the concrete wall--which will be poured solid with concrete. Make sure that the space between the form panels is no more than 16-inches--remember that you can choose between 8-and 16-inches thick for concrete wall.
Close in the ends of the form panels with 2-by-4s and plywood and make sure that all wood forms are well braced on the back sides--one long 2-by-4 from the top of the form to the ground at a 45-degree angle and one long 2-by-4 from the middle of the wall forms--from top to bottom--to the ground. Do this every three to four feet from left to right or right to left of the forms. Use 3-inch screws to attach the bracing to the forms, and drive the forms into the ground at the bottoms.
Order your concrete from any local concrete company and ask that they send pebble mix rather than gravel mix. If the concrete company does not offer the mix, ask for concrete grout and add your own pebbles after the concrete arrives. You can purchase your decorative pebbles at any hardware store. Just add them directly to the concrete truck once the truck arrives.
Pour the concrete mix into the wood forms, and gently tap the sides of the forms to allow the mix to settle; however, do not tap too much so that the pebbles settle into the concrete mix, thus hiding the pebbles. Add vertical rebar down into the wet concrete every 4 feet. Smooth off the top of the wall with a concrete hand trowel.
Remove the forms after 48 hours, wait three to five days, and pressure wash the surface of the wall, removing only the concrete film from the surface of the wall. This will expose the pebbles and stones. You may need to use a wire wheel and 4-inch right angle grinder to help expose the pebbles below the surface, but do so with caution.