Annular Space Grouting
Purpose of Annular Space Technique
The primary goal of annular space is to prevent the water leakage and shut down, stop road movement backfill materials, to secure the liner pipes from any damaged, and to reinforced old structures. Proper application of annular space ensures a long term durability of the pipes and the land development structures such as roads and walls. when an existing culvert has run down to the extent that the voids between the roads are penetrated to the culvert causing it to deflect or collapse at worst. Annular space can be used to fill those voids and eliminates settlement or road damage.
Not all cases of sliplined culvert design are on need for annular space mostly on a very small annular space resulting from the sliplining, and the main pipe is structurally sound. Grouting may not be effective or even justify the cost and effort.
Not all cases of sliplined culvert design are on need for annular space grouting mostly on a very small annular space resulting from the sliplining, and the main pipe is structurally sound. Grouting may not be effective or even justify the cost and effort.
Types of Grout
Grout has traditionally been defined as “a thin, coarse mortar used for filling masonry joints.” In recent years, its definition has been expanded to cover a wide range of concrete and organic compounds used to fill masonry joints or space in or around pipes or liners.
Flowable Fill Grout
Flowable Fills are often used for filling annular space and backfill around pipes. This is comprised of a mixture of cement, sand, and water, sometimes with chemical admixtures put in to affect certain properties of the grout mix. A portion of the cement component can be replaced with fly ash. Fly ash is a cementitious material, usually at a lower cost than cement, which can improve certain properties of the resulting mixture. Fly ash may not be available in all locations.
Reduced Density Flowable Grout
Certain chemical admixtures are available commercially to reduce the density of a flowable fill grout mix. The mixture unit weight may be lowered to 100 pcf, depending on the type of sand and cement used and the percentage of the various components in the mix design. While the annular space can physically be filled with these higher density mixture, the risk of hydrostatically overstressing the HDPE liner will increase as the density of the mixture increases.
Cellular grout is a low-density mix composed of cement and water (or cement, fly ash, and water) with a foaming agent added to inject a large volume into the mixture. This admixture greatly reduces the density, or unit weight, of the mixture, and often will result in 40% or greater air content in the finished product.
Application and Grout Selection
For the application of grouting, different factors may affect the process on annular space therefore it is very important to investigate the details to conclude on a right material components and techniques for grouting.
Condition of Main or Host pipe
Length of the pipe
Volume of Annular space
Change of Elevation
Get in touch!
Contact the specialists at Geo Grout Ground Modification Specialist Inc. of Western United States for your Annular Space Grouting project needs. Call us at (650) 241-2400 for complete information on our Annular Space services or email us at email@example.com to discuss your Annular Space Grouting needs today.