Abstract
Mine Subsidence Protection In Populated Areas.
Grout stabilisation of mine voids is an effective way of treating mine subsidence, even in populated built-up areas. This was demonstrated through a project completed by Menard Oceania at Lambton near Newcastle in 2015.
Mine workings in the area date back to 1906 where borehole seam and welsh bord & pillar workings have been carried out over an extensive mine life, including some areas of pillar extraction. The Mine Subsidence Board developed a strategy with a two pronged approach to addressing ongoing subsidence in the area. The first stage sought to urgently address ongoing subsidence in a localised area of instability, followed by a second stage which sought to strengthen areas of increased pillar abutment loading, particularly around the perimeter of the subsidence goaf, and to fill larger voids in the overburden, each of which risked contributing to future subsidence in the local area.
The project involved pumping 4000m3 of a pre-designed grout mix through twenty two cored holes some 30m deep in the heart of a residential neighbourhood. Critically, disruption to the residents in the area needed to be kept to a minimum, through noise and dust mitigation, whilst speed and safety were also critical to the success of the operation.
Mine Subsidence Protection In Populated Areas.
Grout stabilisation of mine voids is an effective way of treating mine subsidence, even in populated built-up areas. This was demonstrated through a project completed by Menard Oceania at Lambton near Newcastle in 2015.
Mine workings in the area date back to 1906 where borehole seam and welsh bord & pillar workings have been carried out over an extensive mine life, including some areas of pillar extraction. The Mine Subsidence Board developed a strategy with a two pronged approach to addressing ongoing subsidence in the area. The first stage sought to urgently address ongoing subsidence in a localised area of instability, followed by a second stage which sought to strengthen areas of increased pillar abutment loading, particularly around the perimeter of the subsidence goaf, and to fill larger voids in the overburden, each of which risked contributing to future subsidence in the local area.
The project involved pumping 4000m3 of a pre-designed grout mix through twenty two cored holes some 30m deep in the heart of a residential neighbourhood. Critically, disruption to the residents in the area needed to be kept to a minimum, through noise and dust mitigation, whilst speed and safety were also critical to the success of the operation.