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This paper aims to investigate the propagation characteristics of blast-induced ground vibrations in loose dry sand under surface and underground vibration conditions by monitoring the particle velocities and dominant frequencies of artificially generated ground vibrations. For this purpose, a ball drop apparatus was used to generate surface and underground vibrations at different depths. The free fall of the ball induced ground vibrations by impact. A total of 60 laboratory-scale ground vibration monitoring tests were performed on 4 physical models placed in a tank designed for this study. The vibrations were monitored on the surface of the sand filling the tank. The obtained results demonstrated that surface vibrations resulted in higher particle velocities than those generated by underground vibrations and that particle velocities measured on the ground surface decreased as the depth of the underground vibration source increased. The frequency analysis emphasized that only low frequencies (40 Hz). It was also determined that increasing the depth of the vibration source resulted in decreasing the dominant frequency range within the range of high frequencies (>40 Hz).

Madencilik faaliyetleri ekonomiye can veren önemli sektörlerden bir tanesidir. Gerek ülke ekonomisine katkısı gerekse istihdam açısından güçlü bir sektördür. Herhangi bir sebeple üretime ara verilmesi ve ya durdurulması hem ekonomik açıdan hem de mühendislik açısından önemli etkilere sebebiyet vermektedir. Bu sebeple üretimin sürekliliğinin sağlanması gerekmektedir. İlk kez 2019 Aralık ayında Çin'in Wuhan kentinde ortaya çıkan Covid-19 virüsü hızla tüm dünyayı etkisi altına almış ve hayatın her alanını olumsuz olarak etkilemiştir. Dünya sağlık örgütü tarafından küresel pandemi olarak ilan edilen salgın, madencilik faaliyetlerini de etkilemiş, ekonomik açıdan ve üretim sürdürülebilirliği açısından işletmeleri yeni tedbirler almaya zorunlu kılmıştır. Bu çalışmada, madencilik faaliyetlerinin aksatılmaması, aynı zamanda da bulaş riskinin azaltılması veya önlenmesi açısından bir takım öneriler ve tedbirler sunulmaktadır.

Patlatma yöntemi, madencilik, tünel açma faaliyetleri, inşaat ve yıkım işlemleri ve enerji sektörü gibi birçok sektörde yoğun olarak kullanılmaktadır. Ancak, bu yöntem hız ve ekonomik yönden çok verimli bir yöntem olmasına rağmen çeşitli çevresel etkilere ve büyük hasarlara neden olabilmektedir. Bu çevreye verilen olumsuz etkilerin en önemlisi zemin titreşimleridir ve oluşan titreşimin şiddetine ve etki alanına göre maddi kayıplara ve hatta can kayıplarına sebep olabilmektedir. Bu sebeple bu muhtemel etkilerin en aza indirilmesi ya da en iyi ihtimalle bertaraf edilmesi için patlatma faaliyetlerinde zemin titreşimlerinin özel olarak irdelenmesi gerekmektedir. Bu çalışmada patlatmadan kaynaklı zemin titreşimlerinin özellikleri, sınıflandırılması ve temel büyüklükleri sunulmuştur. Ayrıca, yer sarsıntısının yapılar üzerinde oluşturduğu hasarlar, insanlar üzerindeki olumsuz etkiler ve insan algısı ile yapısal hasar arasındaki ilişki detaylı bir şekilde araştırılmıştır. Ayrıca, patlatmadan kaynaklanan sismik dalgalar, arazi katmanları ve yapılar arasındaki etkileşimler irdelenmiş ve Parçacık Hızı PPV, Bileşke Vektörel Toplamı PVS (Peak Vector Sum), parçacık yer değiştirmesi, parçacık ivmesi ve frekans başta olmak üzere yer sarsıntısı hasarının değerlendirmesinde sıkça kullanılan parametreler sunulmuştur., Blasting operations are extensively practiced in mining, tunneling activities, construction and demolition projects and the energy sector. However, despite the efficiency of this method in terms of time and costs, blasting operations can generate numerous environmental impacts and major damages.Ground vibration is the most detrimental impact caused by blasting activities as it can cause material loss and even the loss of human lives depending on its intensity and impact area. Thus, ground vibrations should be thoroughly investigated in order to minimize or ideally prevent their possible impacts.This study examines the characteristics of blast-induced ground vibrations and investigates the properties and types of the body and surface waves resulting from blasting activities. In addition, structural damages caused by ground vibrations, their negative impacts on human health and the relationship between human perception and structural damages are presented in details. Furthermore, the study highlights the interaction mechanisms between seismic waves, ground layers and structures and investigates the most commonly used parameters in the assessment of ground vibration damages i.e. Peak Particle Velocity PPV, Peak Vector Sum PVS, particle displacement, particle acceleration and frequency.

This study investigates in depth Terrestrial Laser Scanning technology (TLS), its working and measurement principle, 3D Terrestrial Laser Scanning softwares and the advantages of this scanning method. This paper also stresses the advantages of adopting this technology in quarries and mines and provides examples of researches that have demonstrated the superiority of TLS systems over the traditional scanning methods in terms of practicability, reliability and accuracy in numerous mining engineering applications such as deformation measurements, rock fall and landslide control, volume calculations and detection of discontinuities.

Crushed stone is the most important raw material for concrete and asphalt production. As a high-volume low-unit-value industry, the crushed stone production sector is highly competitive which implies the necessity to optimise the costs of all of its production operations, i.e. drilling and blasting, secondary breaking, loading, hauling and crushing. In this context, this paper investigates the effect of bench blasting design parameters on the unit-costs and total production cost of aggregate production. For this purpose, 40 blasts were conducted and investigated. The studied parameters included different blasthole length (12 m, 15 m, 18 m, 21.5 m and 25 m) and diameter (89 mm and 102 mm), in addition to different spacing, burden and stemming length. As a result, it was found that an increase in blasthole length led to an increase in the unit cost of drilling operation. In addition, it was found that a blasthole length of 15 m ensured optimum fragmentation, diminishing the costs of subsequent operations. Incrementing the blasthole diameter from 89 to 102 mm reduced the total unit cost by 0.091 $/m3. Incrementing the burden and spacing by 0.25 m also decreased the total unit cost by 0.097 $/m3. However, accreting the stemming length by 0.5 m induced a slight decrease in the total unit cost by 0.026 $/m3.

Mining is an extremely crucial sector that provides the necessary raw materials for several industries. The mining sector plays a significant part in the development and the socio-economical growth of any country as natural resources directly contribute to its value-added and increasing its employment rate. Our country is characterized by the wealth and the diversity of its mineral reserves. Therefore, empowering the production ensures the economic and technological development of the country by creating employment opportunities and meeting the needs in raw materials of several sectors. This paper reviews the international mining market by investigating the top produced minerals and their producing countries. In addition, this review paper studies the development of the mining sector in Turkey in the last few years and its contribution to the socio-economical growth of the country.

Equipment-related occupational accidents are very higher when compared to all other type occupational accidents in the worldwide. Various types and styles of many equipment are used in construction industries (construction and mining). This equipment are usually huge and heavy, so the consequences of accidents are severe. Occupational accidents related this equipment might occur due to operating faulty, carelessly and unserviceably. In this study, the causes of occupational accidents related with heavy equipment in construction workplaces are presented and cause-and-effect relationships of occupational accidents are investigated based on the statistics. Heavy equipment safety types are analysed for incident prevention by statistics. In addition, the detailed information are presented about the precautions to prevent such accidents. As a result, all stakeholders should pay attention to the use of new security technologies and to reduce human default to prevent workplace injuries depending on the equipment.

Since aggregate production has vital importance for many engineering projects—such as construction, highway and plant-mixed concrete production—this study was undertaken to determine how the costs for such production are affected by the design of drilling and blasting processes used. Aggregates are used in the production of concrete and asphalt, which are critical resources for the construction sector. The ongoing population increase and the growth of living standards around the world drive the increasing demand for these products. As demand grows, competition has naturally arisen among producers in the industry. Competition in the market has directly affected prices, which leads to the need for new measures and cost analysis on production costs. The cost calculation is one of the most important parameters in mining activities. Aggregate production operations include drilling, blasting, secondary crushing (if necessary), loading, hauling and crushing-screening, and each of these factors affects cost. In this study, drilling and blasting design parameters (such as hole diameter, hole depth, hole distance and burden) were investigated and evaluated for their effect on the total cost of quarrying these products, based on a particular quarry selected for this research. As the result of evaluation, the parameters actually driving costs have been identified, and their effects on the cost have been determined. In addition, some suggestions are presented regarding production design which may lead to avoiding increased production costs.

Plaster materials are commonly used on the interiors and exteriors of buildings. Such materials protect against impacts, atmospheric degradation, and physical and mechanical effects. Additionally, plaster materials must provide thermal insulation. In this study, rock samples (three types of ignimbrite) produced by Erciyes Mountain volcanic activity were selected as materials. These selected materials have differences in terms of engineering features. Petrographic properties of the samples were determined employing polarization microscopy. Plaster materials were separately prepared from each sample with the determined engineering features. The plaster materials were separately applied to block surfaces. The blocks were then subjected to heat transmission tests. Additionally, a non-plaster material was tested for comparison. The data obtained in these tests revealed important findings relating to energy savings, and it was found that new materials obtained from wastes of ignimbrites and idle resources formed by Erciyes Mountain (Kayseri, Turkey) volcanic activity can be used as alternative materials.

URL:http://sujest.selcuk.edu.tr/sumbtd/article/view/457 DOI: 10.15317/Scitech.2017.98, The natural rocks used today as well as in the history for a variety of purposes were a subject of different alteration, weathering and deterioration conditions. These conditions are strictly controlled by environment and nature of rock varieties (marble and stone). This study is a first approach to understand the relation between some geological features and behavior against salt (Na2SO4) decay of Moroccan marbles and stones. For this purpose, widely used four dolomitic limestones, two crystalline limestones, one limestone and one basalt sample (total 8) were chosen from Morocco. Extra attention paid to choose locations being a representative of all Moroccan country. The carbonate samples (limestone and dolomite) consist of mainly dolomite and calcite with micritic and sparitic cement. The sole, non-carbonaceous sample is basalt of Khenifra containing mainly plagioclase and pyroxene. In general, both bulk-dry and powder density values of the studied rock samples are homogeneous. The limestone of Bir Jdid has the highest (10.81 %) effective porosity and dry weight loss value (4.61 %). The loss on ignition value of the Khenifra basalt has the lowest value with 1.26 %. The loss on ignition values are also relatively uniform. The obtained data indicate that outdoor uses (especially in coastal areas) of limestones of Bir Jdid and dolomitic limestones of Taza are more risky than the others., Hem geçmiş dönemlerde hem de günümüzde çok çeşitli amaçlar için kullanılan doğal taşlar farklı ayrışma, dağılma ve bozunmaya uğramaktadırlar. Bu şartlar çevre ve kayacın türüne (mermer ve taş) sıkı sıkıya bağlıdır. Bu çalışma Fas mermerleri ve taşlarını tuza (Na2SO4) karşı dayanımlarını ve bazı jeolojik özelliklerini anlamak için yapılan ilk çalışmadır. Bunun için Fas’tan getirilen çok kullanılan 4 dolomit, 2 kristalize kireçtaşı, 1 kireçtaşı ve bir bazalt (toplam 8 adet) örneği seçilmiştir. Örnekler mümkün mertebe Fas’ın değişik yerlerinden seçilmiştir. Karbonat kayaçları (kireçtaşı ve dolomit) temel olarak dolomit ve kalsit minerallerinden müteşekkil olup çimento mikrit ve sparittir. Karbonatsız tek kayaç olan Khenifra bazaltı esasen plajiyoklas ve piroksen içerir. Genel olarak örneklerin kuru ve öğütülmüş ağırlıkları birbirlerine benzer. Bir Jdid kireçtaşları en yüksek etkili porozite (% 10.81) ve kuru ağırlık kaybına (%4.61) sahiptir. En düşük ateş zayiatı Khenifra bazaltlarındadır (%1.26). Ateş zayiatları genel olarak homojendir. Eldeki veriler Bir Jdid kireçtaşları ve Taza dolomitik kireçtaşlarının dışarda (özellikle sahil bölgelerinde) kullanımlarının diğerlerine göre daha riskli olduğuna işaret etmektedir.

Estimation of rock drillability is vital for mining and boring operations. For this purpose, many researchers have developed various models and equations to estimate rock drillability. Most of these models aim to determine the drillability of rock and the penetration rate by using the physical and mechanical properties of rocks. Although drillability primarily depends on rock properties, other parameters have an impact on drillability as well. One of these parameters is the rotation speed of the bit. This study investigates the effect of rotation speed of the bit on drilling performance. Drilling tests were performed in the laboratory using rotary core drilling and a diamond drilling machine. The relationships between the physical rock properties and the penetration rate were investigated on 15 different rock types and four different rotation speeds were applied to determine the effect of rotation speed of bit on drilling. The uniaxial compressive strength, density, and P wave velocity show strong correlations with the penetration rate. In addition, if the values of the physical and mechanical properties of the rock increase, the effect of the rotation speed on the penetration rate decreases, i.e., increasing the rotation speed of the bit slightly affects drillability on hard and solid formations.

Knowledge of the abrasion resistance of aggregates is important when using them for asphalt and concrete mixes and highway construction materials. In this study, the usability of natural building stone waste as aggregates for different engineering applications was investigated. To this end, test samples were obtained from a number of natural stone quarries and stone cutting factories. The abrasion tests were carried out on the test samples and results were compared between samples. The abrasion strength values were determined with both the Micro-Deval (MDe) and the Los Angeles (LA) abrasion test methods. A correlation coefficient was also determined between the LA and MDe tests results using an appropriate statistical model.

In this study, we investigated the chemical and physical properties of the volcanic rocks used as building stones in historical places and monuments. The chemical weathering effect of salt crystallization on these stones was measured on the laboratory conditions (in most cases, used samples were very small). For this purpose, the dry weight loss (DWL) test was conducted. The rocks of dacite, andesite and tuffs of volcanic origin have different durability against salt crystallization. The most stable rocks are dacites (DWL 2.06%) which were used in the construction of Hittite monuments at Eflatun. The durability of the stones is closely related to their chemical, mineralogical, petrographical and mechanical properties. The stones used in the historical buildings are generally much more stable than present-day building stones.

This study focuses on main adverse effects of blasting activities, blast induced vibrations and air blast. The monitoring and evaluation of vibrations and air blast are presented, also the causes of these environmental effects are investigated. Data recorded from blasting activities at irrigation channel construction in Apa-Konya were evaluated according to USBM RI8507 and OSMRE (Office of Surface Mining) and DIN 4150 (Deutsches Intitut fur Normung) standards and then its effect of the blast induced vibrations and air blast were examined.

Energy saving is very important parameter in the industry. Rock excavation (cutting) machines represent a major cost item in the mining and tunnel sector. Therefore, determining the optimum cutting conditions is major importance in the sector. Otherwise prediction of the performance and selecting of the rock cutting machines is very important. In literature, there are studies usually related to the prediction of cutting performance referring to materials with adjustable properties.

To study the effect of the textural properties of rocks on their crushing feature, the distribution of particle size, the texture, grinding and crushing characteristics of the rocks were investigated, and the relations among them were then analyzed using statistical methods. The relations between the textural properties and the physical and mechanical features of rocks were determined. © 2006 University of Science and Technology Beijing.