gabion wall brisbane park lakes
Call now

1800 021 800

Due diligence checklist

Geogrid reinforced retaining wall provides innovative solution at Reedy Creek

Posted on: April 21st, 2015

Varsity Heights Engineered Crib Wall Complete

Varsity Heights is in an elevated, premium location at Reedy Creek on the southern Gold Coast. The land offers sweeping views to the ocean, yet offers a tranquil bushland setting.

To enable construction of the main 20m wide road reserve with a 20 kPa load, a retaining wall up to 7m was required to support the embankment.

A concrete crib wall was originally specified as a design and construct item which generally presents no problems, however, subsequent to a geotechnical investigation, the foundation profile revealed a 3.5m deep layer of soft clay, overlaying competent Argilite material.

This in-situ foundation condition initially lead to a foundation design incorporating 450dia bored piles at 2m centres along the length of the front and rear of the wall footing.

This pile design proved to be relatively expensive and presented some constructability issues with the soft clay and the presence of groundwater.

Concrib required a different approach and engaged Geoinventions Consulting Services to offer an alternative solution.

Having considered various possibilities, and with some innovative thinking, Geoinventions offered a hybrid-crib/ geogrid reinforced soil wall design which was to be constructed on some foundation improvement.

Varsity Heights Crib Wall Construction

Varsity Heights Engineered Crib Wall Foundations

Varsity Heights Engineered Crib Wall Construction

Varsity Heights Engineered Crib Wall

This design combines the excellent drainage characteristics of a crib wall face with the remaining structure consisting of reinforced soil using geosynthetics.

The foundation improvement was achieved by a geotextile wrapped rock mattress block beneath the crib section as well as a 750mm deep rock-mattress reinforced at the base with geogrid beneath the reinforced soil zone.

Miragrid 8XT was used in the reinforced soil zone and typically the grid length was 0.8H, where H = wall height.

This innovative design addresses the issues of a high 20kPa surcharge, offering a constructable design whilst delivering a cost effective solution to the client.

For more information call Concrib on 1800 021 800 or click here to contact us.

Tags: ,

CC - Brisbane Website Designers