In advance longwall mining, the safety of mine network, production rate, and consequently, economic conditions of a mine are dependent on the stability conditions of gate roadways. The gate roadway stability is a function of two important factors: 1) characteristics of the excavation damaged zone (EDZ) above the gate roadway and 2) loading effect due to the caving zone (CZ) above the longwall w...

The rectangle packing problem often appears in encasement and cutting as well as very large-scale integration design. To solve this problem, many algorithms such as genetic algorithm, simulated annealing and other heuristic algorithms have been proposed. In this paper, a new heuristic algorithm is recommended based on two important concepts, namely, the corner-occupying action and caving degree...

LKAB’s Kiruna Mine, located in northern Sweden, produces about 24 million tons of iron ore yearly using an underground mining method known as sublevel caving. To efficiently run the mills that process the iron ore, the mine must deliver planned quantities of three ore types. We used mixed-integer programming to schedule Kiruna’s operations, specifically, which production blocks to mine and when...

Abstract Mining advances to greater depth, where the control of rock pressure is central for a successful operation. To handle increasing at LKAB’s Kiruna iron ore mine, LKAB and Montanuniversität Leoben develop novel mining method called “raise caving”. Raise caving based on an active stress management approach. De-stressing slots, which are separated by substantial pillars, developed first pr...

The application of roof-cutting and pressure-relief gob-side entry retention plays a critical role in controlling the stability surrounding rock at entry, easing continuity tension improving resource recovery ratio. excavation 360,803 airway Xinji No. 1 Mine is affected by intense mining 360,805 working face. Hence, to address problem airway, mass blast weakening theory was used this study anal...

Geometric nonlinearity of self-anchored cable-stayed suspension bridges is studied in this paper. The repercussion of shrinkage and creep of concrete, rise-to-span ratio, and girder camber on the system is discussed. A self-anchored cable-stayed suspension bridge with a main span of 800 m is analyzed with linear theory, second-order theory, and nonlinear theory, respectively. In the condition o...

The long-span multi-tower suspension bridge is widely used in the construction of river and sea crossing bridges. load-bearing safety anti-sliding its main cable are directly related to structural a bridge. Failure mechanisms discussed. Meanwhile, tribo-corrosion-fatigue cable, contact, slip behaviors saddle service assessment reviewed. Finally, research trends proposed. It great significance i...

In design and analysis, standard references assume the pedestrian flow as unidirectional. In reality however, pedestrian flow is usually bi-directional. The main question pursued in this paper is that whether the main characteristics of pedestrian flow the same under uni- and bi-directional conditions. In order to achieve this goal, effect of bi-directional stream is inv...