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1. GROUTING. Grouting is defined as the process of injecting suitable fluid under pressure into the subsurface soil or rock to fill voids, cracks and fissures for the purpose of improving the soil. The fluid may be colloidal solutions, cement suspensions, chemical solutions etc. Application of Grouting Stopping water flows in mines, tunnels, parkades , dams, and underground structures Soil stabilization. Underpinning structures, and mining applications. Bearing capacity improvements. Reducing and correcting settlement. Ground improvements. To Provide excavation support. Filling the void between the lining and the rock face in tunneling. Unusual and difficult geotechnical and structural problems.

2. Types Of Grouting Permeation Grouting Compaction Grouting Jet Grouting

3. Types Of Grouting

4. Permeation Grouting It is a type of grouting in which grout is injected into the soil to fill the pores and joints without disturbing the soil’s structure and volume. Thus it permeates coarse and granular soils creating a cemented mass . Various types of binders are used in this grouting technique, the choice mainly depends upon the permeability of soil. It is also known as cement grouting or pressure grouting . When the coefficient of permeability is greater than 10^-2 cm/sec, water-cement mixes are used and for permeability as low as 10^-5 cm/sec, expensive resin-based grouts are used. Soils with K values lower than 10^-6 cm/sec are normally not groutable by permeation method. Types Of Grouting

5. Advantages Of Permeation Grouting: Possible in limited space or where access is difficult. Economical for underpinning applications over alternative methods like removal and replacement or piling. The footprint of excavations is maximum when compared to piled solutions. It can be adopted adjacent to existing foundations. Can be performed without disrupting normal facility operations. Uses Create barriers to groundwater flow. Underpinning foundations. Provide excavation support. Stabilize and strengthen granular soils

6. Compaction grouting : This type of grouting involves injecting a thick consistency of soil-cement grout under pressure into the soil mass, consolidating and thereby stabilizing surrounding soils. The grout mix is designed in a way so that it does not permeate the soil voids or mix with the soil. Instead, it displaces the soil into which it is injected.

7. Advantages Of Compaction Grouting: i ) Compaction grouting is suitable where access is difficult and space is limited. ii) Can be installed in a very short time. iii) Generates minimal site vibration. iv) No spoils are induced. v) No connections to an existing foundation structure. vi) Reduces existing foundation settling significantly. vii) Minimizes soil liquefaction potential due to earthquakes. viii) Provides accurate pressure and placement of aggregate grout structures . ix)Economical compared to some other soil stabilization and ground-shoring methods. Uses: These types of grouting is suitable for loose granular soils, collapsible soils, liquefiable soils, soluble rocks, rubble fills, poorly placed fills, & reinforce fine-grained soil. It improves the bearing capacity of soil. It can repair, stabilize and prevent sinkhole potential. It decreases and corrects settlement. Can be used for the ground beneath settled structures in preparation for lifting and re-leveling them. Suitable for ground stabilization where pipes or conduits are or will be installed.

8. Jet Grouting In this type of grouting, high-velocity fluid jet is used to physically disrupt the ground. The soil is eroded and grout is mixed with the soil during the process and thereby improving it . It is more costly than permeation grouting. There are three systems of jet grouting: Single, double, and triple jet systems . Advantages Of Jet Grouting Effective across the widest range of soil types including silts and most clays. No material disposal and less working room is required. Ability to construct soilcrete around subsurface obstacles and limited spaces. Specific soil layers at depth can be improved without treating soils above. Can be used without disrupting normal facility operations.

9. Uses Of Jet Grouting Underpinning of structures, cut off walls for tunnels and open cuts, and consolidating sandy gravel, soft foundation, or clay soil. It can be used in any situation requiring control of groundwater or excavation of unstable soil. To Provide excavation support. To Seal the bottom of planned excavations.