World innovation – Fully automatic static plate load test with battery-powered hydraulic pump

Anix GmbH presents the world first static plate load tester with battery-operated hydraulic pump, which is currently unique on the market. With this device, static plate load tests can be carried out fully automatically.

Static plate load testers in accordance with DIN18134 are used to determine the load-bearing capacity and deformability of soils and unbound base layers. In the conventional types of the device presented here, a hydraulic hand pump is used to apply the 15 to 20 load levels of the two load cycles by the tester. Typically, a test lasts 20-30 minutes. During this time, the tester must apply the load levels individually and keep them constant. The world novelty is that the hand pump is replaced by an automatically operating battery-operated hydraulic pump (Fig. 2). Once the plate load tester has been set up and adjusted, it automatically applies the standardised load stages in accordance with DIN 18134 (or other standards). This eliminates the time-consuming and labour-intensive process of applying the load stages with the conventional hydraulic hand pump, which requires a great deal of sensitivity and strength from the operator.

‘A fully automatic static plate load tester was a frequently expressed wish of our customers – now we have realised it!’, reports the Managing Director of Anix GmbH and chief developer Matthias Weingart, who has been on the market with his innovative plate load testers since 2004. ‘The reliable and sensitive control of the pump was a particular challenge for us.’

At the end of the test, the deformation moduli Ev1, Ev2 and Ev3 are automatically calculated and saved on an SD card. The results can be printed out on the built-in mini-printer together with the load-settlement curve. An Excel file is provided for creating test reports in A4 format.

The battery-powered pump weighs hardly more than a hand pump. The energy stored in the integrated Li-battery is sufficient for one working day under normal test conditions. The pump battery can also be recharged at the car socket. To set up the plate load tester, the user operates the hydraulic pump sensitively using a joystick (Fig. 3). It is possible to store customised tables with other load levels and for other international test standards on the SD card. With the integrated GPS module, it is possible to record the geographical position of the measurements. Maps can be loaded from the Internet on the PC – with the help of the Excel file – and stored in the protocol.

The plate load tester, which has been in production since 2007 and has been improved several times, is particularly characterised by its compact and stable measuring bridge (Fig. 4). It is equipped with heavy hemispherical feet, which allow optimum positioning, particularly on soft and rough layers, and guarantee stable measurement results even in windy conditions. The settlement is measured using a waterproof industrial displacement sensor, which is placed directly on the centre of the load plate. Thanks to the direct measurement principle, measurements in trenches or core drillings up to 750 mm deep are also possible with the aid of suitable brackets.

The robust electronics box (Fig. 5) is another unique selling point of the plate load tester. It is characterised by the simplest possible user interface and has a backlit LCD display and only six buttons. Four of the six buttons are located on the outside so that the transparent cover can be closed in rainy weather and the device can be operated using these additional four outside buttons. Measurement data is stored on an SD card. Test results can be printed out and recorded directly on site using the built-in mini printer. The electronics box has integrated rechargeable batteries that can be charged quickly (<2h) and allow continuous operation for up to 48 hours. Optionally, the test can also be carried out and analysed according to other international standards (Switzerland, Austria, Italy, Slovenia, Norway, etc.).

Bild 1: Das vollautomatische statische Plattendruckgerät mit Akkupumpe

Bild 2: akkubetriebene Hydraulikpumpe mit Joystick

Bild 3: Bedienfeld der Akkupumpe: Joystick zum Ausfahren/Ablassen des Zylinders, Taste zum Aktivieren des Automatik-Modus, Stop-Taste

Bild 4: Messbrücke des Plattendruckgerätes

Bild 5: Elektronikbox des Plattendruckgerätes