Jim Dowling - Mining Engineer

BACK

 

DEVELOPMENT PLANNING

 

Mine Development is all the essential roadways and other narrow excavations (as compared to stopes) which connect the mineral reserve and associated stoping operations to the surface outlet. The term Mine Development refers to both the network of connections and the act of creating them. A great deal of mine planning is required for all aspects of development. Most development occurs in waste rock, the disposal of which provides little or no revenue. Some mines, especially those working narrow veins, have to mine waste in developments at similar tonnage rates to the mining of ore in stopes. Mine planners have to consider several essential design factors when planning developments, the most important of which are:

Route.
Size.
Shape.
Gradient.
Number and Spacing.

 

 

Main types of mine development

Main types of mine development

 

 

Cross section of a typical single track metal mine development showing track and services

Cross section of a typical single track metal mine development showing
track and services

 

 

Options of cross section shapes for mine developments

Options of cross section shapes for mine developments

 

 

Key gradients in mining

Key gradients in mining

 

 

Ventilation raises to surface are features on long, shallow level developments – perspective view

Ventilation raises to surface are features on long, shallow level developments – perspective view

 

 

Ventilation raise to level above – perspective view

Ventilation raise to level above – perspective view

 

 

Main level development using two headings – perspective view

Main level development using two headings – perspective view

 

 

"In Seam" development using three headings – perspective view

"In Seam" development using three headings – perspective view

 

 

Main level development of a steep vein showing crosscuts, lode drives and footwall drives in cross section

Main level development of a steep vein showing crosscuts, lode drives and footwall drives in cross section

 

 

Main level development of a steep vein showing crosscuts, lode drives and footwall drives in plan view

Main level development of a steep vein showing crosscuts, lode drives and footwall drives in plan view

 

 

Main level development of a steep vein without using footwall drives in cross section

Main level development of a steep vein without using footwall drives in cross section

 

 

Main level development of a steep vein without using footwall drives in plan view

Main level development of a steep vein without using footwall drives in plan view

 

 

Cross section showing crown and sill pillars protecting the lode drive from stoping activity

Cross section showing crown and sill pillars protecting the lode drive from stoping activity

 

 

Plan view and cross sections showing a ‘mini’ footwall drive with drawpoint crosscuts

Plan view and cross sections showing a ‘mini’ footwall drive with drawpoint crosscuts

 

 

Boxhole raising from a footwall drive

Boxhole raising from a footwall drive

 

 

Diamond drilling from a footwall drive

Diamond drilling from a footwall drive

 

 

Longitudinal section showing conventional raising and some techniques to make it safer and easier

Longitudinal section showing conventional raising and some techniques to make it safer and easier

 

 

Main level development of a steep vein with an isometric view illustrating the main level vertical interval

Main level development of a steep vein with an isometric view illustrating the main level vertical interval

 

 

Cross section of a flat dipping vein

Cross section of a flat dipping vein

 

 

Cross section showing why steep dipping veins require greater vertical intervals between levels

Cross section showing why steep dipping veins require greater vertical intervals between levels

 

 

Longitudinal section showing the effect of pay shoot plunge angle on vertical level interval in a steeply dipping structure

Longitudinal section showing the effect of pay shoot plunge angle on vertical level interval in a steeply dipping structure. In this case, the pay shoots are horizontal, plunge angle is 0° so main levels will be closer together to pick-up the lower pay limits

 

 

In this case, the pay shoots are vertical, plunge angle is 90° so main levels can be spaced further apart

Longitudinal section showing the effect of pay shoot plunge angle on vertical level interval in a steeply dipping structure. In this case, the pay shoots are vertical, plunge angle is 90° so main levels can be spaced further apart

 

BACK

 

Copyright © 2021 Jim Dowling