The tests, which will run for between one and five hours, are in response to a strong increase in complaints from residents living along the line.
The first test was due to be held overnight on December 23-24 and is part of a national research project lead by the Ministry of Transport. The trials will run until the middle of February 2020.
Measures include reducing the speed of trains to 60km/h, with the vibrations produced compared with trains operating at 80km/h and 95km/h, with around 30 trains set to operate during the tests.
A special test train, composed of freight wagons with various axle loads, will also operate at a range of speeds such as 40km/h, 60km/h and 95km/h.
The vibrations will be measured 25m from the line, with speed checked by a sensor beside the line.
The tests will determine how serious the problem is, what effect vibrations are having on housing along the railway line, and what the economic effects of reducing operating speed is for freight operations.
