On the 16th May 2012 the 17th Assembly of ZAS was held in Crystal Palace in BTC Ljubljana. Traditionally before the Assembly an expert meeting was organized about topical current economic situation in asphalt industry. The first two topics relate to the sustainable development, protection of natural resources by using alternative materials and efficient energy use through new technologies. The third topic presented new approaches in the design criteria for the award of public procurement in the construction and reconstruction road infrastructure.
The first topic with a title The Properties and Performance of Steel Slag in Asphalt Surfacing Materials was presented by Mr. Nick Jones, the development director for the use of slag at the company Harsco Metal Group Limited.
In an interesting and vivid way he introduced the steel slag from its inception in various processes of iron and steel production to its preparation and processing for future use as a high quality material for the asphalt mixture. He showed that the slag is not a waste, as many mistakenly believed, but high-quality, versatile by-product of steel production. When its properties and the appropriate techniques of preparation and processing is taken into account, a slag is gained which is used for the most demanding asphalt mixes, while preserving our environment and natural resources. The methods of testing of the most important properties of slag as an aggregate and comparison of these properties with the properties and quality of natural aggregates were presented. Since the company Harsco has several decades of experience with the use of slag in asphalt mixtures, we could also see the results of long-term monitoring of the most important properties of laid asphalts. After nearly two decades under traffic the monitored area was still without deformation and with an adequate friction coefficient, in short, safe for traffic, reflecting the true quality and effectiveness of aggregate for wearing courses.
At the conclusion of the presentation, we all agreed that in Slovenia we need to continue the work already undertaken in the use of steel slag and, despite the crisis or even because of it, we need to intensify our efforts to swop the imported natural aggregates with aggregates from slag. Of course also the state needs to contribute with appropriate mechanisms and actively support the companies which seek to achieve the objectives of the adopted strategy of sustainable development.
The second topic was entitled Lignite Energy – a successful source of energy in asphalt industry. The topic was presented by Mr. Jürgen Bauer, sales director for Eastern Europe in the company Rheinbraun Brennstoff GmbH.
He presented the basic properties of coal dust as an effective and environment friendly energy source, comparable to the currently most widely used energy sources in the production of asphalt, natural gas and heating oil. In the presentation the analysis of prices of all three energy sources, relative to the base heating value and normative consumption in the production of asphalt mixes was given. Brown coal dust is according to the stocks of fossil fuels certainly a promising future energy source, but the current economic situation of most construction companies in Slovenia engaged in the production of asphalt mixes, does not allow for quick replacement, or adjustment of the existing asphalt plant to this energy source because of the relatively high cost of remodelling of a burner in a tumble drum and the of the preparation of the corresponding storage for the coal dust (cost estimate is between 0.3 and 0.4 million EUR). Because the energy for the production of asphalt mixes represents high cost, in the future the installation of burners with the possibility of exchange of energy source and the use of the one that will in the open energy market in a given period be the cheapest and at the same time energy most efficient and environment friendly.
The third topic was entitled Tendering of asphalt reconstruction works in accordance with sustainable construction criteria was presented by Marko Gardaševič, DRI Investment Management Ltd., Matic Poznič, DARS and Zvonko Cotič, PRIMORJE.
It was agreed among the conclusions of the 13th Colloquium on Asphalt and Bitumen from 24th to 25th November 2011 that all construction works need to be implemented by the principle of quality and price.
In December 2011, the Board of ZAS decided that the draft criteria for the award of works need to be prepared, which will be submitted for approval and use to the largest clients (DARS, DRSC, municipalities). Under the auspices of ZAS, meetings of representatives of investors, engineers, contractors and institutes were held in spring. The results of the meetings are sets of conditions and criteria for the award of the most demanding reconstruction works, based on the most economically advantageous tender. The conditions that determine the minimum requirements that contractors must meet and which vary from project to project were presented so that they can follow the requirements of the Public Procurement Act. These conditions relate mainly to: references of the provider, minimal equipment (a novelty is an asphalt plant with a nominal capacity of 160 t/h), internal control, technical staff and professional staff. Most economically advantageous tender is selected on the basis of scoring after the criteria, namely: the selling price (determined by the equation), the completion period, distance from the center point of the site from the asphalt plant, technical and operational training, certification (ISO 14001 and OHSAS 18001), the use of alternative sources (slag, the use of recycled materials, reuse of milled materials, ...). Total number of points is calculated as the sum of points obtained in these criteria. The most economically advantageous tenderer is the one who has reached the maximum number of points.
Based on the Public Procurement Act at the end of 2011 the Green Public Procurement was adopted, which currently does not include road construction. The project ReBirth - Promotion of the recycling of industrial waste and building rubble for the construction industry (www.re-birth.eu) was presented, from which the workshop on the topic of green public procurement will be held in June 2012. Following the workshop, the project members of ReBirth (CCIS, ZAG, Primorje d.d.) and ZAS will give the initiative to the Ministry of Finance with a proposal to expand the environmental requirements with the additional group of Road construction. Once these environmental criteria are written down in the act of Green Public Procurement, they will become mandatory for all public procurement in the field. The 17th Assembly consisted of an overview of the past year, including all financial statements and plans for the future.
Despite the difficult economic situation, the association ZAS has last year met all the set tasks and operated financially positive. These have helped faithful members, natural persons and legal entities, and especially new international companies who entered in the Association. This year's Assembly was election so a new Board, the Supervisory Committee and the Court of Honour were elected. President of the association remains Slovenko Henigman, who was unanimously elected into the next mandate. The main emphases in the period 2012 - 2016 are as follows
• to retain the existing structure of professional bodies in the Association (TO ZAS, OZVO ZAS, Section for Education and HI, the Commission for asphalt, TO 06, TO SIST, ...)
• to adapt procedures of preparing asphalt projects to the actual needs and sustainable development
• to realize annual plans of ZAS
• to strengthen the cooperation with other professional institutions and propagate the profession (CCIS, IZS, professional media: Gradbenik, Gradbeni Vestnik, Minerali, ...)
The Assembly ended with the awarding the professor Dr. Janez Žmavc for high jubilee 80 years, Marijan Makovec for many years leading the Supervisory Committee of ZAS and Thomas Glanzer for the work in the Management Board in the period of 2010-2011.