Appendix B - Geotechnical Assessment · OPW23/0179

 Project No. PG-10375                                                                               Page | 12
 June 2023
 Ref: PG-10375, 2023-06-09, LTR VER 1
 Michael Cullen – Geotechnical Investigation - Proposed Residence, 128 Gympie Terrace, Noosaville




Settlements inducted by 2m of drawdown (i.e. 20kPa effective stress increase) are
estimated to result in settlements of less than 5mm. Therefore, it is considered that the
effects of dewatering on the adjoining structures will be minimal.

14.0 CONSTRUCTON MONITORING

Construction vibrations could potentially cause settlement in the loose upper level
sands, thereby damaging nearby structures founded in these strata. Prior to
commencement of construction on site, it is recommended that a detailed
dilapidation survey be undertaken to establish the condition of all existing adjacent
structures.

   14.1Monitoring

It is recommended that monitoring points should be established on the retention
system to check for deflections during excavation. A suggested spacing of the
monitoring points would be 10m along the walls. A regular monitoring program of
these stations should be implemented.

Monitoring must commence before any excavation to establish baseline readings.

   14.2Preconstruction Survey

Prior to commencement of construction on site, it is recommended that a dilapidation
survey be undertaken on the adjacent structures.

This survey should include the following:

     •     The extent of exiting damage (if any)
     •     The general condition of the property, ie. Condition of all exposed columns
           and beams, partition walls and cladding etc.
     •     Road, kerb and channel and footpath condition adjacent development site.

15.0 SITE MANAGEMENT

To maintain the long-term performance of the structure, good management of the
soil conditions and the development is vital throughout the life of the development.

The following are some specific comments with respect to site management.

     •     The ground surface around the perimeter of the buildings should slope away
           from the structure and fall to the stormwater system. Water should not be
           allowed to pond adjacent to the buildings.
     •     Founding soils should not be allowed to become saturated. Saturation of the
           on-site material will result in an increase in settlement potential.
     •     Service trenches under the buildings should be kept to a minimum.