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The current mining operation of mineral resources in QuangNinh province-Vietnam is increasingly complicated. Correspondingly, themanagement of the mine sites becomes more difficult. Records anddocuments of minerals and mine sites are archived in different forms.Database systems are stored dispersedly and insufficiently; in many caseslack accuracy, topicality and have not been linked to each othersystematically. These lead to many difficulties in accessing and extractinginformation for the implementation of management as well as for investorsand people with related interest. In this paper an advanced software hasbeen developed for the management of mineral resources and has beenapplied for Quang Ninh province. The software has improved thesupervision and administration of the mining operation in the province.

Underground coal mining in Vietnam plays an important role tonot only the sustainable coal industry but also the energy and social securityin this country. Although the Vietnam coal industry has produced 35–45million tonnes of raw coal per annum in past ten years, a great volume ofcoal resources remains distributed in complex geo-mining conditions andmostly unmined. This paper presents a brief review of the current andpotential technologies for cutting coal and controlling roof in Vietnamunderground coal mines. From the review, it is concluded that there is anurgent demand on improvement of current technologies as well as oninvestigation for effective application of more advanced mining methodsinto the industry, especially for deep mining at Red River Delta—the largestcoal basin in Vietnam.

Longwall mining is one of the most productive methods forextracting underground coal seams. Although the understanding of longwallmining-associated geotechnical mechanisms has been significantlyimproved that contributes to better ground control, roof rock/top coal fallahead of support (roof fall) has not been fully understood that causes severedamage to equipment and casualty at face. Empirical, theoretical andmodelling methods were successfully used in past studies to understand themechanisms driving roof fall; however, key mechanisms and theirinteractions during the fall were not satisfactorily investigated due tolimitation of each method. This study aims to gain a systematicunderstanding of roof fall mechanisms in longwall operation. A review ofpast studies on roof fall is implemented with emphasis on the principles ofapplied research methods. The study confirms that the interaction betweenroof strata, coal seam and face support largely controls roof fall whilenumerical modelling shows great potential in studying roof fall complexmechanisms. The paper’s findings provide mining engineers/scientists witha systematic understanding on roof fall from which more effective roofcontrol strategies can be further developed.

At present, according to the extraction plan in the year 2020 of Duong Huy Coal Company -Vinacomin, the mining is divided into three main zones: Central Zone extracts 06 faces; South Zoneextracts 2 faces and Northeast Zone extracts 2 faces. The designated total production of all zones is1,880,000 tons/year. To ensure the production of each mining zone, exhaust fan stations are installed atventilation roadway adits with a total of 05 main fan stations. However, in the near future, to ensure andmaintain production activities, the mine is being planned and operated using 03 main fan stations. Thecalculation results for the reasonable working mode of fan stations are as follows: for fan station FBCDZ-8-№32B at level +47 m, airflow is 167.69 m3/s and air pressure is 243.74 mm H2O; for fan station 2K56-№30 level +40 m, airflow is 123.37 m3/s and air pressure is 324.79 mm H2O; for fan station FBCDZ-8-№32B at level +44 m, airflow is 167.69 m3/s and air pressure is 354.99 mm H2O.

Support plans and operation schemes of mine faces are critical technical documents inunderground coal mining management. The development and selection of a reasonable support plan andoperation scheme of the face are complicated because they involve many factors. In specific miningconditions, developing and selecting an appropriate support plan and operation scheme will improve theworking efficiency of equipment, increase labor productivity, and ensure workers' safety. This articleresearched a mining technology for the thin seams, focusing on coal seam 10T in Nam Khe Tam coalmine, 86 Coal Company. From the analysis of geo-mining conditions, the article developed and selecteda reasonable support plan and operation scheme for the face in coal seam 10T. After being used in thefield, the support plan and operation scheme have brought the face efficiency and safety.

Quang Ninh underground coal mines are currently in the phase of finishing up the mineralreserves located near the surface. Also, in this phase, a number of coal mines have opened and preparednew mine sites for the extraction of the reserves at greater depth. Several mines have mined at -350 mdepth and are driving opening excavations at -500 m depth below sea level. The mining at greater depthfaces many difficulties, such as a significant increase in support and excavation pressures. The longwallface pressure is mostly manifested in great magnitude that causes support overloaded and jumped andface spall/roof fall. This paper, based on the geological condition of the Seam 11 Ha Lam coal mine,uses the numerical program UDEC for studying the impact of mining depth on stress distribution aroundthe longwall face. The results show that the deeper the mining is, the greater the plastic deformationzone is. The peak front abutment stress moves closer to the coal wall, mainly concentrating on theimmediate roof and top coal. The top coal is greatly broken, and its bearing capacity is decreased. Somesolutions to the stability of roof strata are proposed, and a proper working resistance of support isdetermined. Additionally, the paper suggests that the starting depth for deep mining in Quang Ninhunderground coal mines should be -350 m below sea level.

Reliable estimation of coal and rock mechanical properties at field scale is a prerequisite for numerical modelling of rock behaviours associated with longwall extraction. This paper describes a systematic approach from data collection, laboratory testing to rock mass properties derivation for simulation of longwall extraction, taking two longwall panels at Quang Ninh coalfield in Vietnam for example. The mechanical properties are verified through comparison with published data of the field, indicating close agreements. A simple numerical model is further developed to demonstrate the proper use of the obtained data. The simulation suggests that the ratio of model length to excavation length should be in the range of 2.5–5; uniaxial compressive strength, deformation modulus and tensile strength can be reduced by a factor of 5.0, 2.13 and 2.0, respectively; and a calibration and validation process must be performed to match in-situ longwall’s behaviours. The approach can be applied for derivation of reliable rock mass properties for numerical simulation of underground excavations.