Basement-construction-vibration-guideline

6.        Vibration monitoring during basement construction process
Basement construction typically involves the construction of retaining walls which may include the
installation of piles via hammer impacts, rotary bored piles or sheet piles which can be installed by
vibratory means. Of interest for these types of noise emissions is vibration transmitted to nearby
structures. Vibration monitoring may be carried out in response to section 4.5 of this guideline or as part
of proactive vibration monitoring.

6.1        Vibration measurement procedures for basement construction process
This section addresses measurement procedures and vibration assessments related to vibration
measurements conducted during the basement construction process.

6.1.1      Vibration assessments

The acoustic consultant may choose to undertake vibration assessments in accordance with an accepted
standard for vibration management such as those described in:

          Australian Standard AS 2187.2-2006 Explosives – Storage and use Part 2: Use of explosives,
           Appendix J.
          British Standard BS 7385-2 Evaluation and measurement for vibration in buildings — Part 2:
           Guide to damage levels from ground borne vibration
          German Standard DIN 4150-2 Structural vibration Part 2: Human exposure to vibration in
           buildings

The chosen standard and the general approach taken for adherence to prediction and measurement
protocols should be included in a report provided to the City of Gold Coast. If the predicted or measured
vibration levels are in excess of the chosen standard, management actions should be implemented as
appropriate to the standard and the vibration levels.

The equipment for vibration measurements used should be selected by a suitably qualified acoustic
consultant and be listed in detail in any report submitted to City of Gold Coast. All vibration
measurements should be carried out using triaxial geophones or accelerometers.

All vibration equipment should have appropriate laboratory calibration certificates.

The transducer should be mounted appropriately on the surface of the building element being assessed
for vibration, or ground mounted next to the building footprint. It is critical to maintain effective and secure
coupling of the transducers to the ground, building foundations, other structural elements or substrates
on which the vibration measurement is undertaken.

The selection of the transducer/s and mounting arrangement should ensure the resonant frequencies
associated with the transducer in its mounted arrangement are sufficiently different from the main
frequencies to be assessed. The preferred coupling method depends on site conditions:

          Where there is a rigid surface (for example, concrete or rock), adhesive or mechanical bonding
           can be used.
          Where the surface is soil, the transducer can be embedded or fixed to an embedded mount (for
           example, 200 mm concrete cube or similarly sized cylinder). If measurements are repeated at the
           same location, it is recommended that an embedded mount is used for repeatability. Coupling
           with soil spikes in soft soil is not recommended.

Instrumentation used for vibration monitoring should be of sufficient sensitivity and frequency range to
allow comparison with the specified criteria. The transducer orientations should be documented and
included in any reporting with respect to the source of the vibration along with information as to the
mounting or coupling of the transducers.




CONSTRUCTION VIBRATION MANAGMENT GUIDELINE (A45139253)                                       Page 12 of 13