A new design concept of fully grouted rock bolts in underground construction

2nd International Conference on Sustainable Development in Civil, Urban and Transportation Engineering

地球科学;运输工程;经济学

Nguyen, Quang Phich^1,2 ; Nguyen, Van Manh^3 ; Nguyen, Ke Tuong^4

Binh Duong University, Binh Duong, Viet Nam^1

Vietnamese Tunneling Association, Hanoi, Viet Nam^2

Hanoi University of Mining and Geology, Hanoi, Viet Nam^3

Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Viet Nam^4

关键词: Closed form solutions;    Different mechanisms;    Geological conditions;    Geological hazards;    Grouted rock bolts;    Interaction mechanisms;    Underground construction;    Underground excavation;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/143/1/012017/pdf
DOI  :  10.1088/1755-1315/143/1/012017

来源: IOP

【 摘 要 】

The main problem after excavating an underground excavation is to maintain the stability of the excavation for a certain period of time. Failure in meeting this demand is a threat to safety of men and equipment. Support and reinforcement are different instruments with different mechanisms. Among the common support systems in tunnelling and mining, rock bolts have been widely used to reinforce rock mass and also to reduce geological hazards. Furthermore rock bolts can be applied under varying different geological conditions with cost-effectiveness. Although different methods are developed for grouted rock bolts design until now, the interaction mechanism of the rock bolts and rock mass is still very complicated issue. The paper addresses an analytical model for the analysis and design of fully grouted rock bolts based on the reinforcement principle. According to this concept the jointed rock mass reinforced by grouted rock bolts is considered as composite material which includes rock mass, the grout material and the bolt shank. The mechanical properties of this composite material depend on the ratio of the components. The closed-form solution was developed based on the assumption that the rock mass arround a circular tunnel remained elastic after installing fully grouted rock bolts. The main parameters of the rock-bolt system (the diameter and length of bolt shank, the space between the bolts) are then easily estimated from the obtained solution.