Vibration Monitoring (VM)
VIBRATION MONITORING (VM)
Foundtest (M) Sdn Bhd is a professional engineering firm which specializes in construction testing services including Vibration Monitoring. The firm utilizes the VIBRA-a, which is FPDA (Foundation Pile Diagnostic Systems) series and software which is specially designed for ground and structural vibration monitoring.
Vibration Monitoring is used to monitor and record vibrations caused by pile driving, traffic, machinery, explosions or other vibration sources. Vibration sensors, placed on the ground or connected to a structure, can be monitored simultaneously. Continuous recording or even triggering mode can be selected during the monitoring process.
The VIBRA-a consist of 3 vibration transducers (geophones) and a data acquisition computer with LCD display. It measures, displays and stores the peak values of the vibrations.
Reliable performance over time in an environment with moisture, dirt and vibrations, demands much of the applied measuring system. Therefore the microcomputer is located in a watertight robust housing and is powered by an internal rechargeable battery or external power. Data from the memory may be transferred to a PC. The measurement results are presented on an LCD screen with clear readable characters and digits.
The standard vibration transducers used for VIBRA-a are velocity transducers (geophones). A Standard 3-D X, Y, Z sensors is supplied. The sensors have a robust polyester case. For correct measuring, the sensor should be leveled accurately (use the circular bubble). The axes of the horizontal components are indicated on the case top.
| Channel | Direction |
| 1 | Vertical |
| 2 | Horizontal (Long Arrow Direction) |
| 3 | Horizontal (Short Arrow Direction) |
The vibration transducers are to be mounted to the structure where the vibrations are to be measured. In most cases a mounting based on gravity is sufficient. The transducers for the vertical and horizontal direction cannot be interchanged. A transducer for the vertical direction will not measure any vibrations in horizontal direction and visa versa.
When the vibration transducers are placed on site and the cable is connected to the transducers and VIBRA-a, the vibration measurements can be started. The VIBRA-a will display the results of the vibration peak value of velocity of vibration.
The time period over which the peak value of the vibration signals is stored can be adjusted with TIMEBASE button. All of the measured values are stored in memory. Data from the memory can be transferred to the PC for result interpretation and report preparation.
