CONSTRUCTION PROCEDURESAND QUALITY CONTROL GUIDELINES FOR EARTHTRAC HA MECHANICALLY STABILIZED EARTH (MSE) STRUCTURES

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703.771.7305413 Browning Ct.Purcellville, VA 20132www.earthteccorp.com

Focus Points

Materials and Components Site Preparation MSE Wall Construction Troubleshooting

Materials and Services Suppliedby EarthTec

Precast concrete facing panels Nominal size 5 x 10

Materials and Services Suppliedby EarthTec

Hard neoprene bearing pads for horizontal panel joints used from the second course of panels upwards.

Materials and Services Suppliedby EarthTec

Geotextile strip, in rolls, for placing against panel joints.

Materials and Services Suppliedby EarthTec

EarthTrac HA ribbed steel soil reinforcing strips, supplied cut to length, and galvanized. nuts and bolts complying with ASTM Grade A325.

Materials and Services Suppliedby EarthTec

Precast Corner / Slip joint panels

Materials and Services Suppliedby EarthTec

Site assistance and training.

Materials and Services Suppliedby Contractor

All labor and supervision.

All safety equipment.

Project specific safety plan.

All tools, construction, earthmoving, lifting and compaction equipment as outlined in the General Notes section of the design.

Backfill in accordance with the Specification.

Materials to install all required drainage systems.

Concrete and forming materials to install levelling pad.

Material to install parapet or copings.

Timber props for first row of panels.

Large and small crow bar for adjusting panels.

Materials and Services Suppliedby Contractor

Timber clamps for temporarily clamping each row of panels until backfilled (1 per vertical joint).

Timber wedges for maintaining panel batter during setting of panels prior to clamping (6 per vertical joint).

spacers (2 per panel). 4 Spirit level. Site level and rod. Plumb bob. Adhesive for securing geotextile at panel joints. Corner or slip joint backing blocks.

Site Preparation

Preparation of Foundation Soils Check that foundation material is consistent with the site

investigation Local soft spots removed and replaced with compacted

granular fill Foundation area is proof rolled

Construct Leveling Pads

Levelling pads may be precast or CIP concrete The levelling pad shall be toweled smooth Constructed to within 3mm (1/8) of the specified

level

Site Preparation

Setting Out (Staking) String lines or pegs Define wall lines

Establishing the Wall Line Front face of the wall is established

with a chalk line drawn on the pad. Line represents the front face of the

panels including any special finish Additional points located at all bends, points of curvature or

tangency of curves

Installing First Panels

Bottom row placed directly on top of the levelling pad Panels set out sequentially in alternating A & B pattern

Panel Installation

Installing First Panels

spacer guide used to achieve the correct front face spacing

Panels checked for alignment and battered back a minimum of 5mm ()

Bottom course propped vertical using 2 x 4 timber props

Rubber or asphalt shims installed if necessary to level the first row

Once the panel is securely held, lifting eyes are removed

Installing First Panels

Bottom panels propped

Applying Geotextile

Apply geo-textile over all vertical and horizontal panel joints

Apply adhesive to panel, not to geotextile

Backfilling to Specification

Lift thickness

First backfill stage up to level of lugs

Fill graded away from facing (temporary drainage)

Backfilling carried out in direction parallel to facing panels

Compaction not performed

directly behind panel until first

strip has been secured with fill

Compaction Equipment

Keep equipment weighing more than 1500kg (1.5 tons) and at least 1.5m (5ft.) away from the facing panels

Fill within 1.5m of the face compacted using a vibrating pedestrian roller or a vibrating plate compactor

Strip Installation

Strips laid out perpendicular to the wall face Connecting bolts inserted so that the nut is

installed on top

Second Stage Backfilling

Backfill to the tops of the B panels

Compact fill outside 5 feet prior to compacting fill immediately behind the panel

Verify horizontal and vertical alignment and adjust as necessary

Provide temporary hand railing

Intermediate Panels

Place two rubber bearing pads on top of each of the lower panels

Intermediate Panels

Place intermediate row of panels on the bearing pads

Adjust for batter and alignment Place timber wedges in horizontal joints to maintain

batter Clamp panel corners to control movement Remove wedges from lower row as soon as the next

layer of panels is positioned

Repeat Sequence

Remove temporary hand railing and place rubber spacers

Lift panels into position and secure with timber clamps and wedges

Check for line, level and joint consistency and record on control sheets

Fix geotextile to back of panels with adhesive Backfill and compact to next lug layer Install strip Reinstate hand railing

Top Panels

Same as for normal panels Additional mortar bedding added to the top of the

panels to provide a smooth line Upper layer of strips deflected to avoid anchor

slabs

Top Panels

Mortar bedding on top of panels

Troubleshooting

Out of Tolerance Condition Negative batter (wall leaning out)

Possible Cause Insufficient batter prior to fill placement Backfill material not within specifications:

More than 2% over optimum moisture content Excessive fines (% passing 200 sieve) Plasticity Index beyond specified limits

Heavy equipment operated within 5 feet of panels Backfill material placed and compacted perpendicular to the

wall Lift thickness beyond specifications Excessive compaction of backfill Clamps and wedges not properly secured

Troubleshooting

Out of Tolerance Condition Positive batter (wall leaning in)

Possible Cause Excessive batter on panels prior to backfill placement Insufficient compaction of backfill

Troubleshooting

Out of Tolerance Condition Difficulty installing upper panels

Possible Cause Levelling pad out of tolerance Panels not level Incorrect horizontal spacing Differential settlement causing panel to panel contact

and spalling

Troubleshooting

Out of Tolerance Condition Bulging or horizontal alignment out of tolerance

Possible Cause Backfill material not within specifications:

More than 2% over optimum moisture content Excessive fines (% passing 200 sieve) Plasticity Index beyond specified limits

Heavy equipment operated within 5 feet of panels Backfill material placed and compacted perpendicular to the

wall Lift thickness beyond specifications Excessive compaction of backfill Saturation of backfill due to rain

Questions?

EARTHTEC, INC.703-771-7305703-771-7306 Fax413 Browning Ct.Purcellville, VA 20132www.earthteccorp.com

Construction ProceduresFocus PointsMaterials and Services Supplied by EarthTecMaterials and Services Supplied by EarthTecMaterials and Services Supplied by EarthTecMaterials and Services Supplied by EarthTecMaterials and Services Supplied by EarthTecMaterials and Services Supplied by EarthTecMaterials and Services Suppliedby ContractorMaterials and Services Suppliedby ContractorSite PreparationConstruct Leveling PadsSite PreparationInstalling First PanelsInstalling First PanelsInstalling First PanelsApplying GeotextileBackfilling to SpecificationCompaction EquipmentStrip InstallationSecond Stage BackfillingIntermediate PanelsIntermediate PanelsRepeat SequenceTop PanelsTop PanelsTroubleshootingTroubleshootingTroubleshootingTroubleshootingQuestions?