ZFG 3000 Light Weight Deflectometer
TIC Service Group Pty Ltd
Geotechnical, Pavement, Geotechnical Engineering
For a highway to perform well over the long term, its soil and aggregate layers need to provide a stiff, stable foundation. Inspections are required during construction to ensure that pavement foundation materials have been compacted enough to ensure this condition. Light Weight Deflectometer’s (LWD’s) are a light weight, portable tool used to determine the stiffness of unbound materials (subgrade/subsoils and base layers, granular layers & backfilling materials) during construction by measuring the deflection under an applied load. This device is hand operated and takes measurements of the deflection of the compacted soil that is impacted by a falling weight. The device measures a deflection and estimates a modulus value based on the force required to generate a given deflection for that soil type.
It provides immediate repeatable results so that on-site decisions can be made straight away and it can be used in confined spaces and difficult to access locations, with no support equipment required.
The Light Weight Deflectometer (LWD) ZFG 3000 from Zorn Instruments is a compaction control device, according to ASTM E2835-11 and ASTM E2583-07 (2011). An optional GPS-System allows the user to immediately determine and record the test position and this is integrated with Google Maps.
The ZFG 3000 equipment measures the dynamic modulus of deformation Evd in the range from 15 up to 105 MN/m². Modulus is the most accurate and independent means for judging deformation (stiffness) and, thus, a material’s level of compaction. Using extensions to the ZFG 3000, dynamic CBR (California Bearing Ratio) can also be measured in-situ in the field and also laboratory CBR in a cylinder can be simulated.
Experimental investigations show measuring depth with a cone of influence to a maximum of 60 cm.
Using the 10kg falling weight, the ZFG 3000 Light Weight Deflectometer (LWD) measures in the range of 15 -70 MN / m². Using the 15kg falling weight (1.5 times the impact load), the measuring range extends from 70-105 MN / m².
The advantages of the ZFG 3000 Light Weight Deflectometer (LWD) include:
- Provide a more representative picture of a pavement’s ability to handle traffic loads than laboratory density measurementsZFG 3000 LWD Light Weight Deflectometer Software
- Direct verification of the soil values used during pavement design
- Results immediately available – no construction delay
- Time saving in testing (a maximum of 3 minutes per measuring point)
- Data interpretation software allows data storage, analysis and manipulation and easy inclusion into reports
- GPS-System for immediate determination of test position integrated with Google Earth
- Readings captured on SD-card for data memory (10,000 data sets) allowing immediate on-site results printing and data transfer to PC for further analysis
- No lab work so inspector stays on-site
- Safer for inspectors: Less time kneeling near traffic at a construction site means fewer accidents
- Direct deflection readings: accelerometer directly connected to the base plate
- Accurate repeatable results
- One-man use: designed for field testing
- Easy to use
- No additional loading vehicle or support is required
- Using extensions to the ZFG 3000, dynamic CBR (California Bearing Ratio) can be measured in-situ in the field and also laboratory CBR in a cylinder can be simulated.
Applications for this non destructive method for compaction control testing include flexible pavements, unsealed roads and mine access roads, tunnels, railway track beds, airport runway and taxiways, hard standing areas, dam construction, canal building, embankments, mobile crane and piling rig foot standing pads (outriggers), building foundations, pipe laying and tank farms.
Clients include those involved in pavement construction, pavement rehabilitation, material testing, geotechnical testing, pavement investigation and site investigation and include road authorities, councils, asset managers, mines, mobile crane operations, engineering and construction groups, EPCM’s, subcontractors, geotechnical consultancies and research organisations.
, Dynamic Deformation Modulus
, Dynamic Light Drop Weight Tester
, Dynamic Load Plate Test
, Dynamic Plate Load Test
, Elastic Modulus
, Falling Weight Deflectometer
, Flexible Pavements
, Geotechnical Engineering
, Geotechnical Testing
, Light Drop Tester
, Light Drop Weight Tester
, Nuclear Density
, Nuclear Densometer
, Nuclear Gauge
, Pavement Rehabilitation
, Plate Bearing Tester
, Preliminary Investigation
, Static Plate
, Static Plate Bearing Test
, Static Plate Test
, Sub Grade
, Sub Soil Evaluation