Elastic stress waves in rockbolts subject to impact loading

✍ Scribed by Xiaoping Yi; Peter K. Kaiser

• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: English
• Weight: 622 KB
• Volume: 18
• Category: Article
• ISSN: 0363-9061
• DOI: 10.1002/nag.1610180205

✦ Synopsis

Abstract

Due to rock bursting or blasting, violent rock ejections can occur. In underground excavations, rockbolts are often used to retain rock blocks that otherwise would be ejected. Employing the stress wave approach, general formulae are derived to compute the elastic stress waves in rockbolts subject to rock block impact loading. Weight‐drop tests on steel rods, simulating impact loading of rockbolts, were performed, and a reasonable agreement is found between theoretical predictions and experimental results. The elastic stress wave in an impact loaded steel rod consists of a rider wave and a lower‐frequency carrier wave. With the same drop height, the carrier wave becomes more sinusoidal as the mass ratio of steel rod to drop weight is decreased.