Rock Engineering Design

Rock Engineering Design:Rock engineering design consists of;

Engineering constraints

Objective

Input Data

Design methods

Output specification

Feedback

Engineering Constraints: Constraints means something that limits your freedom to do what you do. Rock engineer usually related to the rocks suppose purpose of excavation, shape of the excavation (Circular shape, horse shoe shape etc.) etc. Basically there are several factor which control the engineer these factors are;

Function

Size

Shape

Layout

Method of excavation 

Objective: Objective means a thing aimed at or sought; a goal. Rock engineer have basically three objective which is under;

Safety

Stability

Economy

The rock engineer suppose who design the excavation is also know about that the design excavation should be safe, stable and economical.

Input Data: Input data is also called data acquisition. Input data is one of the necessary factor of rock engineering design. Input data consists of;

Geological structure

Rock and rock strata properties

Groundwater 

In situ stress field

Applied loads

Geological data consist of engineering geological mapping and geo  technical core logging. Geological data tells us about the geology of strata. Rock and rock strata properties tells us about the strength, deform ability and factors of influence of the rock strata. One of the critical thing during design the excavation is the condition of ground water. Because due to the presence of ground water the rock strength decrease. 

Design Methods: We only apply three type of design methods which as;

Analytical Method

Empirical Method

Observational Method

The most predominant design approach is the empirical design method.

Analytical methods:

Utilise the analysis of stresses and deformations around openings.

E.g. closed form solutions, numerical methods (finite elements, finite differences), analog simulations (photo-elastic).

Observational design methods:

Rely on actual monitoring of ground movement during excavations to detect   measurable instability and on the analysis of ground-support interaction.

The observational method is a way to check other methods.

Empirical design methods:

These methods asses the stability of mines and tunnels by the use of statistical analysis of underground observations.

For example engineering rock mass classifications.

Output Specification: Output specification tells us about the mines and tunnels. Especially there roof spans, stand-up time and support guidelines. Also tells us about slope and foundations. Especially rock mass cohesion and friction and deformation modulus.

Feedback: Feedback is actually the result of the design. Feedback is actually tells us about the selection of instrumentation for performance monitoring remedial measure in case of instability.http://mobilezonex.blogspot.com.tr/2014/12/methods-of-design-in-rock-engineering.html