Manned vehicle transportation is one of the most important aspects of the oil and gas industry. The oil industry is dependent on the expertise that trucking providers bring, and would not have the ability to function otherwise. There are multiple types of trucks that must be utilized in drilling tasks to complete a job properly. One key factor to consider in land transportation safety is the driver. The major considerations include qualifications, training, and health.
The traditional use of extruded polystyrene (XPS) rigid foam insulation has been to control heat flow between building living space and outside environment; however, new information reveals additional ways XPS rigid foam insulation can be used in heavy load roadway, railbed, and airfield applications. The objective of this paper is to provide engineers with a better understanding of the behavior of rigid foam as an engineered insulation material to support transportation infrastructure in cold regions. Numerous aspects of foam application and performance are discussed in this paper. Aspects include equivalent thermal resistance of foam vs. soil, normalized stress-strain curves of various rigid foam ultimate compressive strengths, cost comparisons between rigid foam and fill, and recent testing results of rigid foam when applied loadings exceed the ultimate compressive strength under repeated loadings. Testing approach was designed to consider loading associated with heavy equipment active in oil and mining operations. Historic design recommendations for use of rigid foam in bearing considerations has been the inclusion of a sustained dead load from which a reduced live load is then utilized. The reduced live load presents challenges in roadway and runway applciations as more fill is required to reduce applied surface loads to lower values, thus disqualifying XPS as a viable insulation solution to support pavement structures under heavy live loads. With the introduction of new data, analysis, and interpretation, XPS is shown to provide a cost-effective thermal barrier between the subgrade and road surface for heavy loads when compared to fill that is sourced far from the construction site. The recent testing of both extruded and expanded polystyrene under heavy and repeated loadings, with thermal resistance comparisons, leads to additional understanding of rigid foam as an engineering material.
3D laser scanning is a unique technology used for the description and subsequent modeling of real shape of spatially complex underground mining environment. Groundbreaking was its application in the pilot deployment of the Room and Pillar method at the CSM mine, where this method was used for the first time within the Upper Silesian Coal Basin, also known to have one of the most difficult mining and geomechanical conditions in the world. Very difficult mining conditions at depth over 800 m warranted searching for complex geotechnical tool or method that would capture all changes without distortion. Despite some shortcomings, 3D laser scanning was selected, although there is still no suitable device for dusty and humid mining environment. During the pillar development phase, comprehensive geotechnical monitoring was undertaken including the frequent scanning of pillar movement using 3D laser scanning technology. Based on repeated time-separated measurements, spatio-temporal analyses of deformation changes during ongoing mining were carried out. These analyses captured dynamic changes in coal rib, roof and floor movements of designated roadways while developing the pillar panel. In addition, time dependent long term post-mining measurements quantified additional strata movements within the panel enabling assessment of the long term pillar and mine roadway stability. The time-lapse scanning indicated variable pillar rib movement with maximum measured displacements of 60 cm. The scans indicated that in most cases, the bottom of the seam displaced more than the top of the rib side due to low floor strength causing large floor heave of up to 100 cm. During the 3-year monitoring, more than 2 billion spatial points were captured that can be used for further analysis.
A considerable amount of coal reserves are located in protection pillars that lie under built-up region in active Czech mining areas of the Upper Silesian Coal Basin. The commonly used controlled caving longwall mining method is not applicable in these areas because significant deformation of the surface is not permitted. For this reason the modified room and pillar method with stable coal pillars has been tested in order to minimise strata convergence. The trial operation of room and pillar method has been implemented at the shaft protective pillar where no mining was carried out in the past. Mining depth of room and pillar trial ranged from 700 m to 900 m. It is perhaps the deepest room and pillar coal mining in the world.
Pictured front row, left to right: Phongthorn Thavisin, Jean-Marc Dumas, Ramona Graves, Janeen Judah, Darcy Spady, Sami Al-Nuaim, Adeyemi Akinlawon, Aizhana Jussupbekova, Cam Matthews, Johana Dunlop; back row: Mark Rubin, Hisham Sadaawi, Chris Jenkins, Andrei Popa, Tom Blasingame, Birol Dindoruk, Elizabeth Cantrell, Karl Heskestad, Erin McEvers, Jennifer Miskimins, Joe Frantz, T.K. Sengupta, and Cesar Patino. Not pictured are Roland Moreau, Jeff Moss, Khalid Zainalabedin, and Helena Wu.
The offshore energy industry continues to grow worldwide into new frontiers using larger than ever, marine equipment. Much of this equipment is infrastructure fabricated at yards located inland from traditional marine terminals which then requires specialized road transports to be used. Concurrently, Marine Assurance agencies are being called upon to act as the verification agency for these transports with one of their primary goals being to ensure the safe transport of the equipment. Despite the relatively high number of marine equipment public road transports, the importance of robust securing of cargo is often underestimated in the industry. Additionally, the required operational Quality Assurance/ Quality Control (QAQC) procedures to be applied for a successful and safe operation are often disregarded. One of the main contributors to these issues is the lack of common guidelines recognized across the industry. The correct understanding of the requirements for the road transport will permit reliable and cost-effective operations to be performed in a timely manner.
IN BRIEF -Many safety rules related to driving exist and are accepted without critical evaluation. This is reasonable as they are ostensibly trained in that area and, thus, in a better position to evaluate the risks inherent in different activities and to assess what can and should be done to alleviate or reduce those risks to an acceptable level. As such, it behooves safety professionals to be aware of not only safety-related heuristics that are presented to the public, but also the research that underlies that guidance to assess the appropriateness of the various safety rules that are promulgated to address potential hazards. In the real world, however, ostensible safety experts often simply accept these rules as representing appropriate, normal or typical behavior based on longevity, common sense or the simple frequency with which they are expressed. One example of this (with which most parents are likely familiar) is the "5-second rule": the idea that food dropped onto the floor and quickly retrieved is still safe enough to eat. The rationale seems to be that bacteria requires a longer time to transfer from the floor surface to the food. In a study by researchers at Rutgers University involving multiple foods, surfaces and contact durations over 2,500 measurements, it was discovered that, while longer contact times result in more bacteria transfer, other factors (e.g., nature of the food, surface onto which it is dropped) are of equal or greater importance (Miranda & Schaffner, 2016). The study concluded that bacteria were found to instantaneously contaminate the dropped food, debunking the idea that eating food quickly retrieved from the floor was safe. Another example is the adage that one should wait at least an hour after eating before swimming. The professed rationale for this practice is to avoid the potential for cramps.
Li, J. L. (Institute of Rock and Soil Mechanics) | Shi, X. L. (Institute of Rock and Soil Mechanics) | Yang, C. H. (Institute of Rock and Soil Mechanics) | Li, Y. P. (Institute of Rock and Soil Mechanics) | Li, H. R. (Institute of Rock and Soil Mechanics) | Ge, X. B. (Institute of Rock and Soil Mechanics) | Yin, H. W. (Institute of Rock and Soil Mechanics)
ABSTRACT: The detection of the goaf area is the key to the treatment of the coal mine goaf. The underwater ultrasonic imaging technology is applied to detect the shape of the water filled goaf of coal mine for the first time in China. The basic principle of ultrasonic imaging technology is explained. The work process of the ultrasonic detection is introduced with a detection case of a coal mine goaf under a railway bridge in Shanxi, China. The ultrasonic reflection signatures of wall, fork and ground obstacle of the mine roadway have been discussed. The post-processing techniques of the ultrasonic detection are proposed to reconstruct the goaf shape from cloud data. Finally, the detection results are compared with the known exploratory drilling data. It shows that the ultrasonic goaf detection has a high accuracy, which can satisfy the requirement of the actual engineering. The detection results provides the key data for the treatment of the goaf area.
Due to the disordered over-exploitation of coal resources, there are plenty of coal mine goafs with unknown shapes in many areas of China (Han et al., 2011a). The exist of coal mine goaf is a safety problem, for it may cause land subsidence and ecological environment destruction, which may bring great damages to the economy and society development of themining area (Wang et al., 2015, Fan and Liu, 2017). The treatment of coal mine goaf have become a current urgent duty.
An accurate and effective detection of goaf area can ascertain the distribution of goaf roadways, which is the key data for the safety evaluation and hazard control of goaf treatment projects. At present, many detection methods have been used in the world, such as the transient electromagnetic method (Han et al., 2011b), high-density electrical methods (Wu et al., 2016), and shallow seismic reflection method (Thomas and Holzer, 1986). Most of these methods are indirect detection methods, which are used to determine the general range of the coal mine gaof area in most cases. The accuracy of these methods is not enough for the actual engineering requirements of the treatment of the coal mine goaf. The laser range imaging method (Ding, 2015) can directly detect the shape of roadway through a borehole, however, it can easily get disturbed by borehole water curtain. Otherwise, the laser can not pass through muddy water, thus the laser range imaging system can not work in water-filled goaf. Aiming at these problems, this paper proposes using the ultrasonic imaging technology to detect the water filled goaf of coal mine for the first time. The basic principle of ultrasonic imaging technology is explained. The work process, data analysis and detection effects of the ultrasonic imaging technology are discussed with an example of the detection of a coal mine goaf in Shanxi, China.
ABSTRACT: In underground coal mining practice, a majority of rocks are composed of clay minerals. When roadways are placed in them, clay minerals are exposed to water and humidity and will absorb water rapidly and generate pressures that can break apart the weakly bonded rock, leading to a progressive strength degradation and consequently a severe closure (i.e., squeezing) of the roadway. In this study, numerical simulation was carried out to investigate the mechanisms of roadway squeezing using UDEC Trigon approach. The strength degradation is simulated by gradually reducing the cohesion and tensile strength of the contacts between blocks in the UDEC Trigon model. The strength is not reduced everywhere throughout the model but only at failed (either in tension or in shear) contacts because moisture is considered to intrude into rock through cracks. When a contact fails, its cohesion and tensile strength are gradually reduced as a function of calculation time. The numerical study aims to realistically capture the squeezing process of the surrounding rock mass of roadway due to strength degradation.
In underground coal mining practice, a majority of rocks are composed of clay minerals, feldspar, quartz clastics, and a small fraction of other silicate and carbonate minerals. Shales probably are the most common and can be composed of 50-80% clay materials (Molinda and Klemetti 2008). Clay materials have a platy structure and can absorb water. Water absorption causes swelling, which may loosen bedding and break apart the flat- bedded material structure, resulting in rock deterioration (Huang et al. 1986). Considerable researches have been carried out to study the swelling characteristics of shale. The propensity for swelling is controlled by the mineralogical composition of the rock, for example the presence of swelling clay minerals and the higher the water absorption, the higher the degree of swelling (Olivertra 1990). Huang et al. (1995) carried out a series of laboratory tests and the results showed that the temperature of the shale had the least influence on swelling of shale, while the air humidity and the moisture activity index had a significant influence. Zhang et al. (2004) found that the low strength of shale is also correlated with low Young's modulus and low shear strength.
Waclawik, Petr (Institute of Geonics of the CAS, Institute of Clean Technologies) | Snuparek, Richard (Institute of Geonics of the CAS, Institute of Clean Technologies) | Kukutsch, Radovan (Institute of Geonics of the CAS, Institute of Clean Technologies)
A part of the coal reserves in the Karvina subbasin of the Upper Silesian Coal Basin is situated in protection pillars that lie under built-up areas. The longwall mining method is not suitable in these areas because significant deformation of the surface is not allowed. The room and pillar method with stable coal pillars has been proposed to minimise strata convergence. The method has been examined within the shaft protective pillar located in CSM-North Mine coal seam No. 30, where the mining depth ranged from 700 to 900 meters, being perhaps the deepest room and pillar panel in coal mining in the world [1–5].
As there is no relevant experience of using this method in the Upper Silesian Coal Basin, an extensive monitoring system has been implemented to enable the mining trial to continue safely. The monitoring is focused on the load-bearing capacity of the coal pillars and strata deformation changes induced by the room and pillar mining method. Precise monitoring was carried out in two adjacent coal pillars located within the row of pillars forming the panel. To monitor roof deformation, fourteen pairs of 5-level multipoint extensometers monitored roof displacements and eleven strain-gauged rockbolts were installed at various locations. Seven hydraulic dynamometer load cells measured the cable bolt loads were installed at the roadway intersections around the monitored pillars.
The integral constituent of the extraction method (using driving machines like the Bolter Miner) is bolting as the sole support system of the roadways. The contribution deals with the behaviour of roof bolting, including the loading of the bolts, yielding of the rock mass and convergence in the roadways. The monitored parameters' database used to measure whether the room and pillar method is successful at this depth forms a necessary condition for verification of this method and its future application in conditions experienced in Upper Silesian Coal Basin.
Waclawik, Petr (Institute of Geonics of the CAS, Institute of Clean Technologies) | Kukutsch, Radovan (Institute of Geonics of the CAS, Institute of Clean Technologies) | Konicek, Petr (Institute of Geonics of the CAS, Institute of Clean Technologies) | Ptacek, Jiri (Institute of Geonics of the CAS, Institute of Clean Technologies) | Kajzar, Vlastimil (Institute of Geonics of the CAS, Institute of Clean Technologies) | Nemcik, Jan (University of Wollongong) | Stas, Lubomir (Institute of Geonics of the CAS, Institute of Clean Technologies) | Soucek, Kamil (Institute of Geonics of the CAS, Institute of Clean Technologies) | Vavro, Martin (Institute of Geonics of the CAS, Institute of Clean Technologies)
Accurate knowledge of the stress-strain state of rock mass, not only in their vicinity but also in the wide surroundings of mine workings, is absolutely critical for precise support designing. Investigation of the rock stress is usually carried out by interpretation of the rock mass deformation processes, which can be relatively precisely observed and measured.
In order to verify the stress state of the rock mass and changes in it induced by longwall mining, monitoring of changes in the rock mass stress in connection with the mine out of the longwall No. 371 202 was carried out. The seam extracted by monitored longwall has a thickness of approximately 2 m at a depth about 1100 m and lies within the Czech part of the Upper Silesian Coal Basin. Interpretation of the initial rock mass stress tensor and verification of its changes during longwall mining were the aims of this stress monitoring. A total of five probes were installed on the roof rocks of the main gate. Two compact conical-ended borehole overcoring probes were installed to obtain the pre-mining full stress tensor and afterwards three compact conical-ended borehole monitoring probes were installed to continuously monitor the stress state in the rock mass ahead of the advancing longwall. The monitored stress development contributes to our knowledge of stress distribution and its changes during excavation at great depth in multi-seam sedimentary deposits of the Upper Silesian Coal Basin.
Knowledge, which should be as accurate as possible, of the stress–strain state in rock mass is the determining factor for the proper planning of roadway supports . That is why stress monitoring, primarily of the changes induced by longwall mining, is considered within this research project. The locality of longwall No. 371 202 in a mine of the Ostrava-Karvina Coalfields (Upper Silesian Coal Basin – USCB) was chosen for the research.