Grouting
Grouting is a process that involves injecting a fluid grout into soil, rock or man made material such as rock fill or masonry. The fluid grout cures and hardens, fills voids, increases strength and reduces the permeability of the ground. In addition to these effects, compaction grouting can be used to displace and compact the ground.
RGE personnel are highly experienced in the field of grouting and our plant fleet includes the specialized pumps and control systems needed to carry out high quality grouting work. Our previous experience includes very large bulk fill grouting projects, some of the world’s most technically demanding permeation and rock fracture grouting, high quality dam grouting, compensation grouting for tunnels and pipelines and jet grouting for earthquake mitigation, water proofing and structure stabilisation.
RGE personnel are highly experienced in the field of grouting and our plant fleet includes the specialized pumps and control systems needed to carry out high quality grouting work. Our previous experience includes very large bulk fill grouting projects, some of the world’s most technically demanding permeation and rock fracture grouting, high quality dam grouting, compensation grouting for tunnels and pipelines and jet grouting for earthquake mitigation, water proofing and structure stabilisation.
Grouting Techniques
Permeation grouting
During permeation grouting, grout is injected into the soil to fill the pores around the individual soil particles. The grout cures and hardens and so creates a cemented block of ground which has increased strength and reduced permeability. Permeation grouting is used in permeable soils such as silts, sands, gravels and man made materials such as rock fill. Grout is injected under pressure into the soil to fill the pores around the individual soil particles. The grout cures and hardens and so creates a cemented block of ground which has increased strength and reduced permeability. |
The technique is also used in underground mining to provide roof support by consolidation and strengthening of rock fill and collapsed rock. Permeation grout mixes are generally based on cements and microfine cements, with silicate and chemical grouts used where finer grained silts are to be treated. Methods include lancing, end of casing grouting and tube-a-manchette techniques (TAMs).
Rock fracture grouting
This technique is used to fill rock fractures with grout. The grout cures and hardens and so increases the strength of the rock mass and decreases its permeability. The technique is commonly used during the construction of dams, tunnels and shafts. Methods of injecting the grout include end of casing, single and double packers and tube-a-manchettes
This technique is used to fill rock fractures with grout. The grout cures and hardens and so increases the strength of the rock mass and decreases its permeability. The technique is commonly used during the construction of dams, tunnels and shafts. Methods of injecting the grout include end of casing, single and double packers and tube-a-manchettes
Compensation grouting
This is one of the more sophisticated grouting techniques. Compensation grouting is used to prevent or mitigate settlement caused by tunneling, particularly from soft ground tunneling. For example, when a tunnel is being driven through soft soils with buildings above the route of the tunnel, the ground loss inherent in such tunneling work tends to cause settlement and damage to structures that are founded above the tunnel alignment. Compensation grouting is used to inject grout into the ground above the tunnel to compensate for the ground loss and hence mitigate or prevent settlement and so prevent damage to the overlying structures.
This is one of the more sophisticated grouting techniques. Compensation grouting is used to prevent or mitigate settlement caused by tunneling, particularly from soft ground tunneling. For example, when a tunnel is being driven through soft soils with buildings above the route of the tunnel, the ground loss inherent in such tunneling work tends to cause settlement and damage to structures that are founded above the tunnel alignment. Compensation grouting is used to inject grout into the ground above the tunnel to compensate for the ground loss and hence mitigate or prevent settlement and so prevent damage to the overlying structures.
Compaction grouting
This is commonly used to compact loose soils which have been by caused by wash out, subsidence, earthquake liquefaction and poorly controlled earthworks. The technique uses a stiff grout paste which is injected into the ground to form multiple bulbs of solid grout. The formation of these bulbs causes the surrounding ground to be displaced and hence compacted. The compaction increases the bearing capacity and reduces the settlement of the insitu soil. The technique can also be used to reverse historic settlement and to fill natural or man made voids within the ground.
This is commonly used to compact loose soils which have been by caused by wash out, subsidence, earthquake liquefaction and poorly controlled earthworks. The technique uses a stiff grout paste which is injected into the ground to form multiple bulbs of solid grout. The formation of these bulbs causes the surrounding ground to be displaced and hence compacted. The compaction increases the bearing capacity and reduces the settlement of the insitu soil. The technique can also be used to reverse historic settlement and to fill natural or man made voids within the ground.
Minefill grouting
Minefill grouting is a bulk void filling technique used to fill and stabilize underground mine voids. Filling of the mine voids prevents their collapse and so avoids ground movement, load transfer onto adjacent pillars and surface subsidence. For abandoned mines, the grouting is carried out remotely using boreholes drilled from the surface. For active mines the grouting may be carried out from the surface or at the stope.
Minefill grouting is a bulk void filling technique used to fill and stabilize underground mine voids. Filling of the mine voids prevents their collapse and so avoids ground movement, load transfer onto adjacent pillars and surface subsidence. For abandoned mines, the grouting is carried out remotely using boreholes drilled from the surface. For active mines the grouting may be carried out from the surface or at the stope.
Jet grouting
Jet grouting is one of the most flexible of ground engineering techniques. The process allows insitu soil to be mixed with a cement binding agent to create soilcrete of strengths ranging from 500kPa to 10MPa. The technique is used to create columns, panels and blocks of mixed soil. Very large columns (1 to 5m diameter) are created using a small diameter borehole (generally 150mm) with equipment that ranges in size from 2t to 50t. Treatment depths are typically 5 to 30m, with the ability to target a specific depth rather than treat the entire borehole. Applications include underpinning, base slab construction, stabilisation of loose ground ahead of tunneling, water proofing and prevention of earthquake liquefaction.
Jet grouting is one of the most flexible of ground engineering techniques. The process allows insitu soil to be mixed with a cement binding agent to create soilcrete of strengths ranging from 500kPa to 10MPa. The technique is used to create columns, panels and blocks of mixed soil. Very large columns (1 to 5m diameter) are created using a small diameter borehole (generally 150mm) with equipment that ranges in size from 2t to 50t. Treatment depths are typically 5 to 30m, with the ability to target a specific depth rather than treat the entire borehole. Applications include underpinning, base slab construction, stabilisation of loose ground ahead of tunneling, water proofing and prevention of earthquake liquefaction.
Grout mix development
Our knowledge of development of grout mixes is extensive. This ranges from bulk fill mixes where locally available materials are used to develop an economic mix, through to the most sophisticated of permeation and rock fracture grout mix development where the chemistry of individual components and their combined effects must be understood. We use cement, micro fine cements, colloidal silica, sodium silicate, bentonite and chemical grouts together with superplasticisers, accelerators and retarders to provide the ideal mix for each project. |