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Energy prices: conclusion

Energy prices: conclusion

Some general conclusions can be drawn in terms of electricity:

1. In every country, governments intervene in order to reduce the electricity cost for some categories of large industrial consumers. These interventions occur on two components: transport (Germany and the Netherlands) and most importantly taxes, levies and certificate schemes (Belgium, UK, Germany, France and the Netherlands). Given the low market prices, the French intervention on commodity prices (ARENH) has become irrelevant

2. Commodity cost plays a very important role: Dutch, French and most of all German consumers are clearly in a more competitive starting position than Belgium. This competitive advantage finds its origin in a lower electricity market price.

3. In terms of overall competitiveness, all countries under review (except for the UK) can offer lower prices than the three Belgian regions for the four consumer profiles, but in case of Germany and France this is only true for (sometimes very) electro-intensive consumers. Prices in Belgium for very large baseload consumers (profile E4) are comparatively more competitive than for smaller consumers such as E1.

4. The United Kingdom is an outlier on the high side for total electricity prices for all profiles under review. This is partly – but not entirely - explained by significantly higher commodity prices, and to a lesser extent by network costs and taxes, levies and certificate schemes.

Gas

As far as natural gas is concerned, some general conclusions can be presented as well:

1. Commodity costs make up a very important part of the gas bill, and their relative importance is higher than for electricity.

2. Price convergence on the commodity market in Belgium, the UK, Northern France, Germany and the Netherlands makes for relatively small differences between the zones under review (except for southern France). For this specific period (January 2016) commodity cost in Belgium is slightly lower than for all other countries under review. Differences in commodity prices are in any case small compared to electricity.

3. For industrial consumers not using gas as a raw material, whether they are large or very large consumers, the Flemish and Walloon regions offer the most competitive total prices. For very large feedstock consumers using gas as a raw material, the competitive advantage of Belgian gas consumers is less important than for other gas consumers, with the Netherlands even offering a slightly lower price. For both consumer profiles the competitive advantage of Belgium is based on a competitive commodity cost, low network costs, and a comparatively low level of taxes and levies.

Competitiveness score

To interpret the Belgian situation in terms of energy cost for industry, we present a competitiveness scorecard that does an effort to summarize the complex and nuanced situation that we have described throughout this report. We address the question whether, based on the consumer profiles provided by the CREG and on the assumptions that we set out earlier on, the energy cost for industrial consumers in Belgium/Flanders/Wallonia/Brussels is competitive when compared to the neighbouring countries (and the price zones within those countries). In section 3.1 of this report, this analysis will be elaborated based on macro-economic data.

For all electricity consumption profiles, only one neighbouring country is certainly less competitive than Belgium: the United Kingdom. Similarly, for all consumption profiles and in all cases, the Netherlands are more competitive than Belgium.

The grey zone represents the complexity of electricity cost for industrial consumers. In Germany and France, for instance, consumers that do not qualify for electrointensity criteria are worse off than their Belgian counterparts. However, for electrointensive consumers benefiting from the existing reductions and exemptions, Germany, France and the Netherlands offer electricity cost that are consistently 15 to 40% lower than in Belgium.

The differences between the Flemish and Walloon regions is most important for profiles E1 and E2 where electricity cost observed in the Walloon region is about 10% above the cost observed in the Flemish region. This difference is reflected in the competitiveness score (the Netherlands and France are certainly less expensive than the Walloon region), and can be solely attributed to regional taxes, levies and certificate schemes. For profiles E3 and E4, the picture is much more nuanced, with a small 2% difference between both regions and the Walloon region being more competitive for E3, while the Flemish region is more competitive for E4.

In terms of industrial gas consumers, the situation depicted by the competitiveness scorecard is very different. For profile G1, the three Belgian regions are more competitive than all other zones/regions under review. For profile G2, the situation is slightly more nuanced. When considering both the top range prices (no feedstock) and the low range prices (feedstock) separately, the Belgian regions are more competitive than the other zones/regions. The grey zones in the competitiveness scorecard reflect the uncertainty that is linked to possible reductions that can be obtained based on economic parameters in neighbouring countries.

The competitiveness scorecard in Figure 33 is a good attempt to summarize the general picture in terms of competitiveness of electricity and gas prices in Belgium and its regions vis à vis its neighbouring countries, but it hides some of its complexity regarding to the competitiveness of electricity prices. As was shown in section 7 of this report, some industrial consumers in the neighbouring countries benefit from considerably lower prices because of reductions based on electro-intensity criteria. This is not the case in Belgium, where reductions are largely based on consumption only.

Therefore, it makes sense to present a competitiveness scorecard comparing electricity and gas prices in Belgium and its regions with those of consumers that benefit from reductions (electro-intensive consumers) and those that do not (nonelectro-intensive consumers) in the neighbouring coutnries. They are presented in Figure 34 and Figure 35 respectively.

 
Support and Reinforcement in the Mining Cycle

Support and Reinforcement in the Mining Cycle

The most commonly used mesh is probably welded mesh made of approximately 5 mm thick steel wire and having 100 mm square openings. The steel wire may be galvanised or not. The alternative has been an interwoven mesh known as chain link mesh. The disadvantage of traditional chain link mesh compared with weld mesh has been the difficulty of applying shotcrete successfully through the smaller openings available. This difficulty has now been overcome in a high strength, light weight chain link mesh with 100 mm openings which is easy to handle and can be made to conform to uneven rock surfaces more readily than weld mesh.

A feature of this mesh is the fact that the intersections of the wires making up the squares in the mesh are twisted rather than simply linked or welded. Roth et al. (2004) describe static and dynamic tests on this mesh. Mesh of this type is being used successfully at the Neves Corvo Mine, Portugal, where it has been particularly successful in rehabilitating damaged excavations. Li et al. (2004) report that this mesh is being trialled by St Ives Gold, Western Australia. Tyler & Werner (2004) refer to recent trials in sublevel cross-cuts at the Perseverence Mine, Western Australia, using what a similar Australian made high strength chain link mesh. It is understood that completely satisfactory mechanised installation methods have yet to be developed.

In this symposium, Hadjigeorgiou et al. (2004) and Van Heerden (2004) discuss the use of cementitious liners to support, protect and improve the operational performance of ore passes in metalliferous mines. One of the benefits of cementitious liners is the corrosion protection that they provide to the reinforcing elements. Both papers emphasise the need to consider the support and reinforcement of ore passes on a cost-effectiveness basis taking into account the need to rehabilitate or replace failed passes. The author has had the experience of having to recommend the filling with concrete and re-boring of critical ore passes that had collapsed over parts of their lengths.

Although their use was referred to at the 1999 symposium, there have been significant developments in the use of thin, non-cementitous, spray-on liners (TSLs) since that time (e.g. Spearing & Hague 2003). These polymer-based products are applied in layers of typically 6 mm or less in thickness, largely as a replacement for mesh or shotcrete. Stacey & Yu (2004) explore the rock support mechanisms provided by sprayed liners.

The author’s experience at the Neves Corvo Mine, Portugal, is that TSLs are useful in providing immediate support to prevent rock mass deterioration and unravelling in special circumstances (Figure 2), but that they do not yet provide a cost-effective replacement for shotcrete in most mainstream support applications. In some circumstances, they can be applied more quickly than shotcrete and may be used to provide effective immediate support when a fast rate of advance is required. Recently, Archibald & Katsabanis (2004) have reported the effectiveness of TSLs under simulated rockburst conditions.

Overcoming the limitations and costs associated with the cyclic nature of underground metalliferous mining operations has long been one of the dreams of miners. More closely continuous mining can be achieved in civil engineering tunnelling and in longwall coal mining than in underground hard rock mining. Current development of more continuous underground metalliferous mining systems is associated mainly, but not only, with caving and other mass mining methods (Brown 2004, Paraszczak & Planeta 2004).

Several papers to this symposium describe developments that, while not obviating the need for cyclic drill-blast-scale-support-load operations, will improve the ability to scale and provide immediate support and reinforcement to the newly blasted rock. Jenkins et al. (2004) describe mine-wide trials with hydro-scaling and in-cycle shotcreting to replace conventional jumbo scaling, meshing and bolting at Agnew Gold Mining Company’s Waroonga mine, Western Australia. Neindorf (2004) also refers to the possibility of combining hydro-scaling with shotcreting to develop a new approach to continuous ground support in the development cycle at Mount Isa. These developments form part of the continuous improvement evident in support and reinforcement practice in underground mining.

As was noted at the 1999 symposium, although backfill has been used to control displacements around and above underground mining excavations for more than 100 years, the great impetus for the development of fill technology came with the emergence of the “cut-and-fill era” in the 1950s and 60s (Brown 1999a). It was also noted that fill did not figure prominently in the papers presented to that symposium. A few years earlier, paste fill made from mill tailings and cement and/or other binders, had been developed in Canada (Landriault 2001). Since that time, the use and understanding of paste fill have increased dramatically, so much so that Belem et al. (2004b) suggest that it is “becoming standard practice in the mining industry throughut the world”.

Cemented paste fill is now used with a range of mining methods including sublevel open stoping, cut-and-fill and bench-and-fill. In some applications, it is necessary that unsupported vertical paste fill walls of primary stopes remain stable while secondary stoping is completed. In common with Landriault (2001) and Belem et al. (2004a), the author has had success using the design method proposed by Mitchell (1983). A particular requirement in some applications is to include enough cement to prevent liquefaction of the paste after placement (Been et al. 2002).

In two papers to this symposium, Belem et al. (2004a, b) discuss a range of fundamental and applied aspects of the use of cemented paste fill in cut-and-fill mining generally, and in longhole open stoping at La Mine Doyen, Canada. Varden & Henderson (2004) discuss the use of the more traditional cemented rock fill to fill old underground mining voids at the Sons of Gwalia Mine, Western Australia.
Tax Burden for Electricity Consumers

Tax Burden for Electricity Consumers

When analysing and summarising the results in terms of electricity, it is interesting to see how the third component (taxes, levies and certificate schemes) compares between the different consumer profiles. In Figure 34, the orange bars represent the total cost per MWh of component 3: taxes, levies and certificate schemes.

The full yellow bars represent the minimum- maximum ranges where different options are possible, while the transparent yellow bars represent the maximum range for nonelectro-intensive consumers in Germany, France and the Netherlands. The red lines represent the weighted average tax burden of the four consumer profiles for a certain country (in EUR/MWh) (for electro-intensive ranges in UK, FR and NL).

Each of the Belgian regions allocate the total burden of extra costs (simplified: tax burden) differently, but one common trend is clearly visible: the more one consumes, the lower the tax burden. In contrast, the UK grants no reductions based on volume and allocates the tax burden completely evenly over the four profiles.

Nevertheless, we also observe that the majority of the other countries under review (Germany, the Netherlands and France) have shifted towards electro-intensity criteria regarding the allocation of the tax burden, while Belgium still defines exemptions strictly based on consumption (same for the three regions). Indeed, in Germany, France and the Netherlands, we observe large possible differences within one single consumer profile depending on the economic profile and the electrointensity of the consumer. In Belgium, on the other hand, we observe important differences only between different consumer profiles, which are mainly caused by differences in consumption level and grid connection level (apart from some general sector conditions).

In other words, from a fiscal point of view, Belgian federal and regional authorities mainly grant reductions and/or exemptions to taxes, levies and certificate schemes based on the level of electricity offtake, and not on the level of electro-intensity of an industrial consumer. This could possibly mean that tax revenues are directed toward protecting consumers that are not particularly affected by a lack of competitiveness of electricity prices, while more vulnerable consumers keep suffering from an important disadvantage compared to their electro-intensive competitors in neighbouring countries.

As is the case for profile G1, the commodity cost is by far the largest part of the total gas price. Price differences are fairly limited. Commodity cost is cheapest in Belgium, followed by the Netherlands, Northern France, Germany and the UK. The South and South West of France have to deal with a higher gas market price, which constitutes a competitive disadvantage compared to the Northern part of the country.

Network costs only make up a limited amount of the total cost. We observe the lowest values in Belgium, and slightly higher values in the Netherlands and France (for both TSO’s). Tariffs in the UK are markedly higher than in the other countries under review.

As to taxes and levies, all countries under review give exemptions for large baseload industrial consumers. All volume based exemptions have already been taken into account in the maximum option in Figure 32. For these results, that only apply to consumers that do not use gas as raw material, we observe the highest tax levels in Germany, and the lowest in the Flemish and Walloon regions.

For consumers that use natural gas as a raw material (feedstock), all countries under review apply important tax exemptions on top of some existing volume reductions. This is the case for Belgium (energy contribution), Germany (Energiesteuer), France (TICGN), Netherlands (Energiebelasting) and the UK (Climate Change Levy). The general level of taxes and levies for these feedstock consumers, reflected by the minimum option in Figure 32, is hence very low for all regions under review. Nevertheless, due to the federal contribution on which no exemptions apply, Belgium offers the highest level of taxes for these feedstock consumers.

Impact of reductions on network costs

As briefly stated above, the impact of reductions on network costs for large baseload consumers such as profiles E3 and E4 are important. Germany introduced these reductions in 2012 and the Netherlands in January 2014. Belgium, France and the UK do not grant reductions.

In Germany and the Netherlands, large baseload consumers such as E4 in this study can benefit from a transport tariff reduction up to 90%. As shown in Figure 37 below, these reductions profoundly alter the situation in terms of transmission tariffs, and by doing so the general picture in terms of competitiveness.

In both cases, the cost is transferred to the other consumers. In the Netherlands these reductions are compensated by the transport tariff itself (through regulatory accounts, for instance). In Germany, a separate levy (the “StromNEV §19-Umlage”) was created to pay for the reduction. It is due by all consumers, but yet again reductions for large consumer profiles are granted on this levy. We can therefore say that high transmission tariffs in Germany are not the consequence of the reductions, but rather the cause.

In terms of natural gas for very large industrial consumers (profile G2), Belgium generally offers very competitive prices. For very large industrial feedstock consumers using natural gas as a raw material (bottom range), cost differences between the countries under review are relatively small, except for the UK that offers a substantially higher cost. For these consumers, the Netherlands and Belgium are the most competitive countries under review, followed very closely by Northern France. The three Belgian regions are more competitive than all other regions, except for the Netherlands that offers a slightly lower total cost.

For very large industrial consumers that do not use natural gas as a raw material, but rather for heating and other purposes (top range), cost differences between the countries under review are much more important. Belgium is generally very well positioned, with comparable consumers in the Netherlands paying up to 5% more. Consumers in the UK, Germany and France can pay up to 20 – 30% more than comparable consumers in Belgium.
Corrosion of Steel Strand

Corrosion of Steel Strand

Corrosion of high carbon steel strand can be a serious problem in long term civil engineering applications. In mining, however, the incidences of cablebolt corrosion causing serious problems are rare. This is due primarily to the short time frame involved in open stope support in underground mining.

Corrosion problems observed by the authors in mining environments were typically in long term support in open pits where the groundwater was acidic or saline and in long term support in underground sulphide deposits. Cut and fill applications in wet conditions where fractured stope backs could remain (supported) for up to a year were notably susceptible to corrosion. Serious failure, due to corrosion and rupture of the strand, can occur in such applications.

The nature of corrosion is extremely complex and a fundamental discussion is beyond the scope of this book. It is the intent here to discuss some of the important factors involved in corrosion so that the engineer may assess the potential for problematic corrosion and take steps to prevent it or make the appropriate design allowances for it.

Most common refined metals are inherently unstable ionic materials composed of arrays of single atoms which possess a full compliment of electrons. Metals such as iron normally tend to give up electrons at room temperature (gold is a notable exception) and become involved in reactions leading to the formation of more stable compounds such as iron oxide or iron hydroxide (rust). The release of electrons is termed an anodic reaction and the acceptance of electrons a cathodic reaction. Both reactions must occur for corrosion to take place. Since metals such as the iron found in steel cable are normally willing to give up their electrons, it is normally the presence of a cathode which determines the corrosion potential.

The cathodic reaction (involving the consumption of electrons released anodically from the iron) can be made possible by the presence of an acid, sulphate, water and/or oxygen.

Corrosion of steel (iron) can be divided into four basic categories (Illston et al., 1979; Pohlman, 1987):
  • Dry corrosion
  • Wet corrosion
  • Corrosion of immersed metals and alloys Induced or accelerated corrosion (includes influence of stress)
The following discussion is confined to corrosion of cablebolts and as such is incomplete as a comprehensive examination of general corrosion.

Dry Corrosion

Dry corrosion is an inevitable consequence of medium- to long-term storage of cablebolts in even the most ideal conditions. It involves the formation of iron oxide (Fe0) as iron atoms combine with atmospheric oxygen. Once the process initiates on a clean surface, it spreads fairly rapidly to involve most of the exposed surface. While Fe0 forms an adherent film on steel surfaces and can actually form an impervious layer, it can be vulnerable to cracking and as such fresh iron is constantly being exposed and the process continues. In the perspective of cablebolting in mining, however, dry oxidation is a relatively slow chemical process and is of only minor consequence. Light surface (dry) corrosion has been shown (Goris, 1990) to improve bond performance of cablebolts by up to 20% in ideal conditions, although deliberate rusting of cablebolts is not advocated by the authors. The process is accelerated by higher surface temperatures (e.g. if the cables are exposed daily, over long periods, to direct and intense sunlight).

Heavy surface rust on newly shipped cables is usually the result of exposure to moisture and subsequent atmospheric corrosion which can be very detrimental to the performance of the cablebolts.

Wet or Atmospheric Corrosion

In a wet or humid environment, the corrosion process is accelerated and can involve a wider variety of cathodic reactions. Water and oxygen become jointly involved in the cathodic reaction and result in other compounds such as 2Fe(OH) ,3Fe O (magnetite), or Fe O (hema 3 4 2 3 tite). These compounds are much less adhesive then FeO and less likely to form a self-arresting film.

Corrosion products formed on cablebolts by wet corrosion are more likely to have a greasy feel as compared to the dry, rough texture of FeO film and are more likely to be associated with other film substances such as oils and additional moisture. These products are likely to have a detrimental effect on bond capacity of cablebolts. Clearly, unchecked corrosion reduces the cross-sectional area of steel in the cable and ultimately reduces the tensile capacity of the steel to unacceptable levels. Ductility and displacement capacity is also reduced (embrittlement).

The presence of water on the surface of the cablebolt also increases the potential for galvanic corrosion. The same wet corrosion cathodic reactions occur, accelerated by the presence of an electrolyte such as chloride, sulphate or hydroxide. Without electrolytes in a static solution, the corrosion process is self-limiting. Iron ions (e.g. Fe ) move into solution adjacent to the steel surface 2+ leaving behind free electrons (2e ) in the steel solid. The concentration of iron ions -in solution and free electrons in the steel creates an electrical potential difference which resists further dissolution of iron ions.

The effects of electrolytes in the surface water is best illustrated in the above example. A drop of water on the surface of the steel contains a dissolved electrolyte such as sodium chloride (which forms a solution of free sodium, Na ,+ and chloride, Cl , ions). The presence of electrolytes permits the transport of iron - ions as FeCl away from the corrosion (anode) site at the centre of the drop. At the same time, water and oxygen combine at the perimeter of the drop with the free electrons from the steel to form hydroxide ions (OH ) balanced by Na in solution. - + These move in the opposite direction to the FeCl generating a current (electron flow) in the steel supplying electrons to the drop perimeter as more iron ions go into the solution at the drop centre. Between the active centre (anode) and the drop perimeter (cathode) the iron ions combine with the hydroxide to form ferrous hydroxide.

This in turn becomes a relatively stable and complex hydrated oxide known as rust. The sodium and chloride transport ions are freed to carry on the process. The cyclic nature of the process combined with the fact that the corrosion product (rust) is not deposited at the anode (as it is with dry corrosion) means that this form of galvanic corrosion is not self-limiting and can be very aggressive. This is particularly true in mining environments given the high concentration of chloride and sulphate ions in mine waters (Minick and Olson, 1987).

Moist corrosion is particularly enhanced by crevices such as those formed by the flutes of a cable. Crevices are particularly good at retaining moisture and the conditions are perfect for differential aeration with low oxygen supply at the tip of the crevice compared with the rest of the cable. If a weak electrolyte is present, an aggressive corrosion cell is thus generated. This corrosion is particularly detrimental as the corrosion product (rust) readily fills the flutes of the cable preventing the penetration of grout and seriously reducing the cable/grout interlock essential for cable bond strength.

Cara Menghitung Volume Galian dan Timbunan Jalan

Cara Menghitung Volume Galian dan Timbunan Jalan Dengan Excel- Proyek jalan merupakan pekerjaan yang mengandung beberapa item pekerjaan mayor dan minor. Semua item pekerjaan tersebut tercantum dalam kontrak dan BOQ. Beberapa contoh item pekerjaan mayor pada proyek jalan nasional adalah pekerjaan aspal, pekerjaan agregat, pekerjaan galian dan timbunan. Pada artikel ini akan dibahas mengenai perhitungan volume galian dan timbunan untuk opname pekerjaan. Opname adalah perhitungan volume dan biaya yang sudah dikerjakan di lapangan. Tujuan dari opname lapangan adalah mengetahui realisasi volume terpasang untuk dijadikan tagihan ke owner proyek. 
Cara menghitung volume galian dan timbunan pada setiap proyek memiliki metode yang berbeda- beda. Metode perhitungan sangat tergantung dari kontrak terhadap owner. Apabila owner menghendaki menggunakan sistem point cloud dan surface maka bisa digunakan beberapa alat yang canggih seperti Laser Scanner. Apabila owner menghendaki metode perhitungan yang konvensional bisa menggunakan alat ukur Total Station, Theodolit, dan Waterpass. Khusus untuk proyek jalan dengan owner Bina Marga masih menggunakan metode konvensional. Oleh karena itu kita akan membahas metode pengukuran dan back up perhitungan volume galian dan timbunan tanah. 
Langkah- langkah pengukuran galian dan timbunan tanah sebagai berikut. 
  1. Sebelum mulai pekerjaan galian atau timbunan pada tanah eksisting perlu di clearing terlebih dahulu. 
  2. Setelah diclearing, dilakukan pengukuran MC-0 (Mutual Check 0%). Pengukuran dilakukan dengan cara cross tiap 25 m atau sesuai kesepakatan. 
  3. Dilakukan pekerjaan galian atau timbunan tanah sesuai dengan design 
  4. Ketika waktu opname pekerjaan, dilakukan pengukuran cross kembali di tempat yang sama. Maka didapat hasil pengukuran yang akan dijadikan acuan untuk menghitung volume galian dan timbunan tanah. 
Hasil pengukuran cross ini berupa nilai x dan y di tiap titik pengambilan data. Dalam 1 Cross terdiri dari beberapa titik pengukuran tergantung dari design galian. Berikut contoh hasil rencana galian tebing pada proyek jalan. 
Daerah yang diarsir merupakan rencana galian tanah. Sehingga data yang kita butuhkan untuk menghitung volume adalah data x,y pada sisi kanan dan kiri badan jalan. X merupakan jarak dari center line jalan ke titik galian. Sedangkan Y adalah beda tinggi dari centerline jalan ke titik galian.  Berikut contoh hasil pengukuran cross dari gambar di atas
Galian Sisi Kiri       
          at point  X=  -3.1116  Y= 102.7074  Z=   0.0000
          at point  X=  -3.3162  Y= 102.5028  Z=   0.0000
          at point  X=  -5.7749  Y= 102.3799  Z=   0.0000
          at point  X=  -8.1289  Y= 102.3799  Z=   0.0000
          at point  X=  -8.5900  Y= 102.4300  Z=   0.0000
          at point  X= -10.2000  Y= 104.9600  Z=   0.0000
          at point  X= -11.0000  Y= 105.0910  Z=   0.0000
          at point  X= -11.8000  Y= 106.7910  Z=   0.0000
          at point  X= -11.1319  Y= 106.7954  Z=   0.0000
          at point  X=  -8.6359  Y= 105.9948  Z=   0.0000
          at point  X=  -7.6021  Y= 104.4644  Z=   0.0000
          at point  X=  -6.1000  Y= 102.5590  Z=   0.0000
          at point  X=  -3.1116  Y= 102.7074  Z=   0.0000
          at point  X=  -3.3162  Y= 102.5028  Z=   0.0000
Galian Sisi Kanan
          at point  X=   5.7175  Y= 102.4373  Z=   0.0000
          at point  X=   6.1000  Y= 103.1060  Z=   0.0000
          at point  X=   7.6000  Y= 103.0860  Z=   0.0000
          at point  X=   8.9799  Y= 103.0676  Z=   0.0000
          at point  X=  10.0000  Y= 103.0420  Z=   0.0000
          at point  X=   9.3000  Y= 102.3490  Z=   0.0000
          at point  X=   7.7938  Y= 102.4176  Z=   0.0000
Tiap proyek mempunyai format data xy yang berbeda-beda. Ada yang menggunakan koordinat global, koordinat lokal ataupun Jarak dan Beda tinggi. Pada Data pengukuran di atas untuk X menggunakan jarak dari centerline, sedangkan y menggunakan elevasi lokal. 
Untuk mengecek kebenaran data koordinat di atas apakah sesuai dengan bentuk galian tanahnya, bisa diplotkan ke grafik di Excel seperti gambar berikut. 
Jika data x,y setelah diplot sudah sama berarti koordinat itu benar. Selanjutnya sekarang kita harus menghitung volume galian tanah terlebih dahulu. Untuk menghitung volume diperlukan Luas Area Galian dan Panjang Galian. Untuk menghitung luas kita harus menggunakan rumus koordinat. Rumusnya adalah sebagai berikut. 
Saya akan memberikan contoh perhitungan untuk luas galian sebelah kana jalan dengan koordinat di atas. 
Luas  = (5.72 x 103.11 - 6.10 x 102.44) + (6.10 x 103.09 - 7.60 x 103.11) + (7.60x103.07-8.98 x 103.09) + (8.98x103.04 - 10.00 x103.07) + (10.00 x 102.35 -9.30 x 103.04) + (9.30 x 102.42-7.79 x 102.35) + (7.79 x 102.44 - 5.72 x 102.42) = - 5,099 
Luas = -5,099/2 = 2,55 
Maka luas galian tanah di sta 22+275 adalah 2,55 m2
Misal luas di sta 22+300 adalah 3,56 m2 maka volume galian tanah dari Sta 22+275 s/d 22+300 adalah 
Volume = (2,55 + 3,56)/2 x 25 m = 76,38 m3
Mudah bukan cara menghitung volumenya? Anda tidak perlu khawatir akan menghitung dengan kalkulator karena kita sudah menyediakan format perhitungan excel gratis tinggal download link di bawah. 
Untuk menghitung volume timbunan tanah juga metodenya sama. Intinya harus diketahui terlebih dahulu berapa koordinat sebelum digali dan setelah digali. 
Demikian artikel tentang Cara Menghitung Volume Galian dan Timbunan Jalan . Semoga bermanfaat.
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