Underground stress engineering: the lifting and stabilization of underground voids

The theoretical basis of how grout, i.e., concrete, pumped into rock fractures prevents the caving of underground tunnel and cavity roofs is presented, and the calculation of how much grout material must be injected to lift a dome and create a useful rubble stope in an underground cavity is described. (LCL

Theft in Price-Volatile Markets: On the Relationship between Copper Price and Copper Theft

Recently, against a backdrop of general reductions in acquisitive crime, increases have been observed in the frequency of metal theft offences. This is generally attributed to increases in metal prices in response to global demand exceeding supply. The main objective of this article was to examine the relationship between the price of copper and levels of copper theft, focusing specifically on copper cable theft from the British railway network. Results indicated a significant positive correlation between lagged increases in copper price and copper cable theft. No support was found for rival hypotheses concerning U.K. unemployment levels and the general popularity of theft as crime type. An ancillary aim was to explore offender modus operandi over time, which is discussed in terms of its implications for preventing copper cable theft. The authors finish with a discussion of theft of other commodities in price-volatile markets