3. Installation of First Unit

• Mark front line with ‘blue’ or ‘red’ string for front wall alignment.
• Mark corner of first unit with a perpendicular front line for wall alignment.
• Place mortar on leveling pads in a small ‘hump’ about 4 in., 0.10m wide and 0.05m high or as needed. (Do NOT level mortar, it will spread under the load of the unit automatically).
• Make sure mortar is plastic to stiff for joints 1 to 4cm
• Use rather liquid mortar for joints 1 to 3mm further up, between units
• Keep tools ready for checking level installation of units: min. 3 ft., 1m, better 5 ft., 1.50m long bubble level (check level for accuracy: must show equal reading after turning it 180°)
• Use long chains with min. 45° steep chain or even steeper: do NOT use short chains
• Have 2 men guiding every unit from truck to final position
• Have rigger directing the crane only: no shouting, signs only
• Never have any person going, standing, working UNDER a hanging load
• Lift unit to be installed with tools (crow bar or wedge bar)
• Use 4 such tools under each leg if needed
• Do NOT damage bottom edges of units, use special care to keep bearing bottom surface intact
• Observe mortar squeezing out under the unit front and legs
• Add more mortar under legs as needed

4. Installation of Side-by-Side Units and or Upper Layer Units

• Maxi units have top of wall finished by hand and thus are not totally smooth and level
• For preventing concentrated contact pressures, cracking, and spalling use joint filler or mortar on top directly before installing the next unit
• Use rather plastic mortar and lay a ‘sausage’ shape at the center and mortar on and around dowels
• Do NOT put mortar on self aligning keys: such mortar would diminish their function
• Leave spaces open for ‘bleeding’ drainage from free draining material directly behind front panels
• Do not spread the mortar: the next unit erected on top will squeeze the fresh the mortar and equalize it
• The top ten feet of wall DO NOT need mortar beds, since contact pressures are much less near the top of the wall
• Filling can start right after installation of units, since filling takes time and mortar must NOT reach full strength immediately
• Start with filling free draining material directly behind the front panel for drainage (to prevent water back-up and ice forming at this critical location)
• Then fill first layer inside along the front and along the back beams inside and outside, to get easy access for compactors
• Start compaction at front and then work backward
• This means: NEVER fill behind units then compact, because empty unit may dislocate from compaction or wheel load directly behind back beam
• Fill both sides of back beam before entering with compaction equipment
• Generally compact every Maxi unit in 3 to 4 layers (0.4 to 0.5m thickness)
• Check acceptable compaction using nuclear gage for fast reading and for not holding up erection procedures
• Compact with light compaction equipment, such as vibratory plate and or jump and jack trench compactor. Compact especially along the legs and in corners
• Prevent empty fill locations under back beams by pushing soil underneath from the sides
• Normally 6 passes are sufficient or compaction
• Check filling operation for minimum MOIST density of 118 pcf, 1.8 t/m3 or 18 kN/m3
• Do NOT use minimum Proctor density or Relative Density criteria for checking fill compaction inside of precast units: This is inside of a cell and NOT a road base: Road base requirements are NOT applicable inside a cell!
• Do NOT OVER-COMPACT, because each pass means creating compaction pressures on the front panel. Each compaction pass creates an additional deformation, which may overload and damage the front panel and leg.
• Do NOT use vibratory rollers all the way to the front for compaction: Worst is operation with vibratory rollers compacting all the way to the front and then throw in the reverse gear: such shock-stops have broken front panels!
• Compact fill inside of units immediately after filling
• First fill and compact inside, then backfill and compact behind units for preventing dislocations
• Backfill operation should always be lower than filling of units by a minimum of 3 ft., 1m and with a back-slope not more than 1v:2h.
• Use heavy vibratory rollers (such as 20 t vibratory rollers) for backfill and use lifts up to 0.5m for mass compaction
• Heavy vibratory rollers must stay away from concrete units at back of wall min. 3 ft., 1.0m.
• Check backfill operation and compaction for minimum compaction requirement for mass fill, such as 95% Proctor (‘relative’) density or overriding mass filling compaction requirements
• Use nuclear gauge for fast readings and easy control without holding up filling operations.
• Contact Evergreen Wall, Inc. for any questions that may come up.