$1\mathrm{.}1.$ Differentiate between the following support types used in mining excavations: Rock bolts and Shotcrete

$1\mathrm{.}2.$ A zinc mine is planning to extract ore at a depth of $600$ meters. The rock density is $3050k\frac{g}{m^3},$ and the UCS of the rock is $160$ MPa $.$ The cube factor of the rock is $65\%$ of the UCS. The proposed dimensions include $9$ m wide bords and $4\mathrm{.}5$ m wide pillars at a stoping height of $2\mathrm{.}5$ m $.$ Use the factor of safety to assess the proposed pillar dimensions and recommend if they are sufficient to maintain stability.

$1\mathrm{.}3.$ You are the rock engineer for a platinum mine that is operating at a depth of $900$ meters below the surface. Recently, the mine has experienced a series of rock falls, prompting a review of the current support systems. The rock mass has a density of $2800k\frac{g}{m^3},$ and based on recent surveys, the $95\%$ cumulative fallout height has been determined to be $1\mathrm{.}4$ meters. The mine uses elongates with a load capacity of $180$ kN each. Your task is to design a new elongate support system to improve safety and reduce the risk of rock falls. Your design must also include support resistance, area supported by each elongate, and the support spacing on dip and strike.

$1\mathrm{.}4.$ Explain the role of backfill in underground mining support and list Five types of backfill systems used.

MIN$3707$

September $2024$

Question $1$: Support of mining excavations

$1\mathrm{.}1.$ Differentiate between the following support types used in mining excavations: Rock bolts and Shotcrete

MIN$3707$

September $2024$

Question $1$: Support of mining excavations

$1\mathrm{.}1.$ Differentiate between the following support types used in mining excavations: Rock bolts and Shotcrete