Metal Madenciliğinde Yeraltı Açıklıklarının Tahkimatı Ve Nümerik Yöntemler İle Analizi

Abstract

Eczacıbaşı Esan Balya Kurşun – Çinko Yeraltı Maden İşletmesi, Türk metal madenleri sektöründe önemli çalışmalara imza atmış bir maden işletmesidir. Esan 2009 yılı itibarı ile Balya’da çalışmaya başlamıştır. Üretim miktarını her yıl katlayarak arttıran firma son yıllarda kurşun – çinko üretiminin en büyük söz sahibi haline gelmiştir. Esan Balya İşletmesi Türkiye’nin Ege Bölgesi, Balıkesir ilinde bulunmaktadır. Balya ilçesine yürüme mesafesinde bulunan işletmeye kadar toplu taşıma ile ulaşım sağlanabilmektedir. İşletmede genel olarak bölge halkı istihdam edilmektedir. Tecrübeli çalışanlar gözetiminde şantiyede sürekli yeni çalışanların yetiştirilmesi bölge halkına kattığı önemli katma değerlerden biridir. Derinliği halen artmakta olan Balya İşletmesi, yatay dilimli dolgulu yöntem ile cevher üretimi yapmaktadır. Cevher, yeraltından kamyonlar ile taşımaktadır. Yerüstüne çıkarılan tüvenan cevher kırıcı, değirmen ve flotasyon gibi zenginleştirme ünitelerinden geçerek konsantre haline getirilir. Ocağa hava gönderen fanların toplam kurulu gücü 1255 kW’dır. Havalandırma sistemi nakliye yoluna ters olarak havalandırma kuyularından girip ana rampa üzerinden ocağı terk etmektedir. Bir vardiyada yeraltında yaklaşık 80 personel ve 40 iş makinesi çalışmaktadır. İş yoğunluğuna göre bir vardiyada 3, 4 veya 5 ayna patlatması yapılmaktadır. Bir vardiyada ortalama 30 m3 püskürtme beton uygulanmaktadır. Maden kazılarından sonra açılan boşluklara uygulanması gerekli tahkimat tasarımlarının deneye dayalı ve sayısal yöntemler ile gerçekleştirilebilmesi için gerekli olan veriler, gerçekleştirilen deneysel çalışmalar ile aynaların devam etmesi sırasında bu bölgelerden alınan ayna haritalarından elde edilmiştir. Bu veriler analitik yöntemlerle analiz edilip tahkimat tasarımları ortaya çıkartılmıştır. Nümerik yöntemlerle ise ortaya çıkan bu tahkimat sistemlerinin uygun olup olmadığı incelenmiştir. Ayrıca geçmişte sorun yaşanan bölgeler incelenip bu bölgelerde kullanılması gereken tahkimat sistemleri nümerik modelleme yardımı ile belirlenmiştir. Yapılan deneylerin nizami olması ve nümerik modelleme programına mümkün olduğunca çok parametre girilmesi sayesinde analitik yöntemlere göre hazırlanan tahkimat tasarımları nümerik modellerle yüksek derecede uyum sağlamıştır. Bu uyum sayesinde fiziki olarak açılmamış bölgelerde simülasyon yardımıyla oluşabilecek problemlere önceden önlem almak mümkün olacaktır. Riskli bölgelerde çalışma yapmadan önce simülasyon ile analiz yapmak işin aksamasına sebep olacak faktörleri ortadan kaldırabilecektir.

Eczacıbaşı ESAN Balya Lead – Zinc Mine is an underground mine which has achieved good works as a metal producer in Turkey. ESAN is a company constructed under Eczacibasi which mainly interested only for the production of industrial minerals suck as clay, bentonite, quartz, etc. Balikesir Balya lead and zinc underground mine started to work in Balya at 2009 as a first example of the Company’s underground mine in metal production industry. The company has become the largest exporter of lead-zinc among Turkish producers with an exponential increase for each year in terms of production number. Balya underground mine has been operated by cut and fill mining method and total depth of mine still keeps increasing. Esan Balya Mine field is located in Balıkesir which is in the Aegean region of Turkey. Local people are working both underground and flotation plant. The mine has a mineral processing plant that used floatation system to produce lead and zinc as a final product. The company is also very beneficial for the local people by employing and educating them about mining and the number of local people employed has been increasing under the supervision of experienced operators. The underground mine is operated by cut and fill underground mine production method. Sublevels with 5 m intervals are developed for the production of ore. A main transport gallery nearly 2.4 km length connects to a ramp which is nearly 3 km length to reach the down of the ore deposit. The horizontal level and sublevel galleries are driven up to the ore and ore galleries are constructed for the excavation of ore material. Ore is transported by trucks from underground to surface up to the surface storage area. The excavation is applied by drilling and blasting methodology with drilling machines and blasting materials. The excavated and transport mine ore is being processed in mine plant by crushing, milling and flotation. The mine ventilation networks is also supplied by fans. The total installed capacity of the ventilators which send air to the underground is 1255 kW. Fresh air comes from ventilation shaft and exhaust air is being sent out from mine by transportation roadway. There is about 80 staff and 40 machines working in one shift. Depending on the intensity of work, 3, 4 or 5 face blasting can be performed in underground. 30 m3shotcrete is being applied by shotcrete machines per shift. The main has a strict production policy to reach the daily and annual target as well as strict policy for mine and labors safety and health. After opening of the tunnels, the initial support systems of the underground spans are designed with respect to the necessary data for application with empirical and quantitative methodologies. These data will be analyzed by analytical methods for support designs to be understood. Numerical models are being used for compatibility of these support designs. At the same time, the areas having support problems were examined by numerical modelling. According to the test results, numerical methods of support designs are impressively convenient with the analytical methods. This situation gives opportunity to examine problems before the excavation. First of all existing data to put number on the geological structures of the underground was investigated and the underground rock mass materials are classified. When the geotechnical properties of each different rock mass environment are determined, the types of the underground openings are determined as well. The size and the shape of the underground openings as well as the influence of the existing galleries are investigated based on geotechnical properties of rock mass. Support designs of the underground openings were then carried out for the underground openings. Mainly shotcrete, fibrecrete, wire mesh and rock bolts are used as support systems in the underground. In very rare situation for the worst conditions of the underground, steel ribs are also used. The engineering properties of these support systems are also determined for the use in numerical analyses systems. After determination of the all required data regarding rock masses, underground openings shapes, and support systems properties, the support systems are determined based on analytical methods by using rock mass classification systems such as rock mass rating (RMR) and quality (Q) classification. The determination of the support design from rock mass classification systems made possible to investigate the suitability of the support system for each underground openings for different rock mass environment. Numerical methods carried out by Phase2.0 software were used to success of the proposed support system design. Hence, the suitability of the rock support systems designed by rock mass classification systems are tests and approved by numerical methods which is the main subject of this thesis. The results are then compared with the actual status of the mine by using the actual rock falling phenomena occurred in the underground mine. As a results of that a methodology is proposed for the design of support system for the underground mine by using empirical, analytical, and numerical methods. Consequently, the thesis is a well-defined case study as well as proposing a methodology for the use of rock mass classification systems with numerical methods in order to propose a proper underground design system which is quite vital for the mine and people.