Grouting Materials

Grouting is a procedure that involves grout injection into voids, fractures, and cavities in rock mass in order to improve their strength and durability, to reduce permeability. Grout can divide  in to three categories by material wise such as Cement-based grout- is the most common type of grout and the least expensive, commonly ordinary Portland cement is applicate widely, clay grout – bentonite slurry is applicable in geotechnical application for the retaining the structure, chemical grout – which special ability is high penetrability than others, commonly applicable in tunnel work.

Special properties of grout is flow – ability which should penetrate through the void space and fill the grout in to it , low shrinkage -resistant to contrast and strength- which capacity to resist the force exerted by loadGrouting procedure whether its can be grouted or not, choice of grout type and amount, help of drilling bore hole detail and geological data, number of drill holes, pattern and depth will decide from preliminary surveys data.

Among the techniques of grouting permeation grouting is commonly used its relatively economical, time efficient, environmentally inert. This is commonly done by chemical grout.

Graphite, Bentonite, Silica sand and Fly ash common mineral which are also available in srilanka. New composite are introduce to achieve some desired properties such as Strength Mechanism, Workability, Admixture, Cost and Less Environment Impact. Advantage of bentonite based grout is its natural so there is no environmental impact and it has ability to absorb the water by its self into it structure and swell which will benefit for the water retention will for strength of grout.

This type of grout which is also applicate in dam such as Moragahakanda Dam. It’s can maintain PH of underground water and surrounding. Silica nanoparticles hold great potential of replacing the organic molecule based grouting materials currently used for this purpose. Chemically, silica nanoparticles are similar to natural silicates which are essential components of rocks and soil.

Moreover, suspensions of silica nanoparticles of different sizes and desired reactivity. Chemical properties of silica nanoparticles to the mechanical properties to better understand their functionality and stability as grouting material. Pulverization improves remarkably the behavior of Fly ash suspensions. Fly ash is an excellent pozzolanic material with hydraulic properties which are improved by pulverization Fly ash concretes develop compressive strength approximately equal to 40% of the strength of concretes without fly ash and exhibit satisfactory durability.