Rock Structure Rating is a quantitative method for describing quality of a rock

Rock (geology)

In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...

 mass and appropriate ground support, in particular, for steel-rib support, developed by Wickham, Tiedemann and Skinner .

The RSR concept introduced a rating system for rock masses. It was the sum of weighted values in this classification system. There are considered two general categories:

• geotechnical
  Geotechnical engineering
  Geotechnical engineering is the branch of civil engineering concerned with the engineering behavior of earth materials. Geotechnical engineering is important in civil engineering, but is also used by military, mining, petroleum, or any other engineering concerned with construction on or in the ground...
  
   parameters:

rock type; joint pattern; joint orientations; type of discontinuities; major faults; shears and folds

Fold (geology)

The term fold is used in geology when one or a stack of originally flat and planar surfaces, such as sedimentary strata, are bent or curved as a result of permanent deformation. Synsedimentary folds are those due to slumping of sedimentary material before it is lithified. Folds in rocks vary in...

; rock material properties; weathering or alteration. and

• construction
  Construction
  In the fields of architecture and civil engineering, construction is a process that consists of the building or assembling of infrastructure. Far from being a single activity, large scale construction is a feat of human multitasking...
  
   parameters:

size of tunnel; direction of drive; method of excavation.

The RSR value of any tunnel section is obtained by summing the weighted numerical values determined for each parameter. The RSR concept is a very useful method for selecting steel rib support for rock tunnels. As with any empirical approach one should not apply the concept beyond the range of the sufficient and reliable data used for developing it. For this reason the RSR concept is not recommended for selection of rock bolts and concrete

Concrete

Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...

 support.

See also

• Core recovery parameters
• Hoek-Brown failure criterion
• Rock mass classification
  Rock mass classification
  Rock mass classification systems are used for various engineering design and stability analysis. These are based on empirical relations between rock mass parameters and engineering applications, such as tunnels, slopes, foundations, and excavatability...