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Glynn Holleran, Vice President, V.S.S Asphalt Technologies, USA Dejan Ristic, Director, ITG, USA Back to VSS Technology Papers Library ABSTRACT: Since the advent of ISO 9000 standards many companies in USA and around the world have improved their operations by the use of Quality principles. Contracting in road pavement maintenance can similarly benefit. This paper examines the ISO 900 requirements and illustrates how a contracting company can use QA to improve its performance. The points are illustrated by case studies from Russia and New Zealand. INTRODUCTION: Quality, is it important? Is it difficult to achieve? In many industries with the advent of ISO 9000 standards quality assurance and total quality management concepts have been introduced successfully, cost effectively, and have saved companies doomed by inefficiency. (1). In the road surfacing industry quality assurance has started slowly. Overseas experience in Australia, New Zealand and Europe (2) has shown that contracting industries are capable of having quality programs and making them pay. In such areas authorities are able to generate the trust to allow it to happen. Pavement maintenance is becoming of pivotal importance in most countries. Even the USA has seen the need for improving funding in these areas and in many countries, e.g. China and Russia (1,3) maintenance has become a significant issue where dollars are scarce. The key factors that lead to adequate performance of such maintenance treatments are: a) Appropriate selection of jobs relative to the distress factors- failure modes. b) Materials. c) Design ----------------------------- 1. Vice President Valley Slurry Seal Co PO 1620 West Sacramento Ca 95688 2. Technical Director ITG 5841 Edison Pl. Carlsbad Ca 92008 d) Application e) Understanding of "success" relative to that process. Two methods of maintenance that are especially useful according to long practice, and now confirmed (4) are slurry surfacing and chip sealing. The natural outcome of such systems is a situation where the contractor takes over the maintenance of a road system on behalf of the customer. e.g. as has occurred in New Zealand. QUALITY SYSTEMS: The best known quality systems are based on the International Standards Organization series 9000. (5). This is a framework within which a company can operate to ensure that the main principles are being followed, that is, the bases are covered. It is not a specification and makes no assumptions about the correctness of any physical process. It is simply the process by which quality can be achieved. A recent study in Northern California showed that 1.2 billion dollars is lost every year to the community, caused directly by the state of the roads- the want for maintenance. Quality is about money, not prices but relative costs. Quality is about fitness for purpose. Quality is about cooperation to produce controlled, expected outcomes. That is it works, it does what the customer thought it would do, it achieves the stated and implied purpose of the customer. Quality is a process, it is about customers both internal to a process and external to it. In roads it encompasses the raw materials suppliers, the design engineers, and the contractors. But customers are not always what they seem! Quality is not extra testing, or inspection or policing, it is about creating a process that meets a mutually agreed outcome. QUALITY ISO 900 AS APPLIED TO SLURRY SURFACING AND CHIP SEAL: Microsurfacing and slurry seal are thin surfacing layers applied by means of a specialized travel paver. They consist of a mixture of crushed and graded aggregates, fillers, asphalt emulsion and water. Often additives are used to moderate the setting characteristics of the mixture. The mixture is made in the pugmill of a traveling machine and laid through a drag box. This box may be specialized for rut filling or as a full lane width (or greater) surfacing. The main difference between microsurfacing and slurry seal is the thickness of the layer. The slurry seal is laid one stone thick (up to 9.5mm or so), the microsurfacing is laid at 2-3 times the thickness of the top size stone and may be laid in several lifts. (up to about 100mm). To achieve this requires a highly cohesive mixture, and special care is taken with materials. Aggregate selection, binder selection (polymer modified systems with latex or solid polymer pre-blended with the asphalt), and emulsifiers to ensure rapid break and cure, are all extremely important. Such systems have been successfully applied on all pavement surfaces from heavily trafficked Interstates to residential streets, and under all weather conditions. (6). Chipseals are a surfacing consisting of an application of a binder by spraying with a subsequent application of a single sized aggregate (7). This may be repeated to build up multiple layers. The key quality features of chip seals are binder quality, aggregate grading and, shape, texture,cleanliness, design and application. Elements such as spray temperatures, equipment calibration, rolling and traffic control are very important. Often chip seals can be used in combination with slurry or microsurfacing to create hard wearing Cape Seals (8) that may be used on heavily trafficked roads. QUALITY REQUIREMENTS: There are several basic items that need to be considered for a good surfacing job. They are: Appropriate application: The planner must know what is required and expected by the customer. This includes aspects of stated and implied needs. That is, will it meet the expectations of the customer? Allied to this is the need to properly pre-treat the surface, that is, crack filling, pot hole filling, rut filling, removal of contamination or line markings. Decisions need to be made on traffic level, the existing texture and what is required, the skid resistance, the appearance and the climate that is prevalent. Specifications in existence: Ensure that the customer and the contractor agree on what is to be done and what the outcome will be. This may be in terms of performance, construction outcomes or materials requirements. MATERIALS: What type of binder, what size and grading of aggregate, additives, fillers, water (in emulsion systems)? How will these be assessed in the laboratory to produce a mix design? What equipment should be used, how should it be calibrated or otherwise certified as accurate? What standards of workmanship are required? What field inspection and quality control testing is required to audit the job to ascertain compliance with the design and customer expectations (i.e. specification). In many cases materials must be modified or changed. These aspects must be included in any quality plan and addressed to both the contractor and customers satisfaction. All are part of the slurry process. They will have stages of working with the suppliers of materials and equipment to ensure that the elements of the process are reproducible at all points. Special requirements must be taken into account: In the Russian context temperatures of +40C to -30C needed to be allowed for. This meant special attention to binder rheological properties, binder content in the mix and additives in emulsion. The chemical nature of the asphalt needed to be accommodated to ensure emulsion stability and rapid cure in the field. This was a part of the QFD and FMEA analysis. GENERAL REQUIREMENTS OF QUALITY ASSURANCE DEVELOPMENT - VSS: Quality systems must work in the interest of the contractor and the customer. Thus the contractor must be able to identify quality as a positive factor in their business and not as an imposed burden costing more money! The first step in developing a quality assurance system for a company, is to outline the primary business processes of the company. The main elements of the QA system are then straight forward and can be related to the elements of the standard. KEY ELEMENTS OF QA DEVELOPMENT: Quality Assurance is about control of systems. The ISO standards clearly map out the programs. Again we are looking at establishing a reproducible system. Below are some key areas that effect total performance in project work. MANAGEMENT RESPONSIBILITY (ISO 9001 Clause 4.1): The management must define and communicate a Quality policy. This policy relates to the overall mission and vision of the company and sets the stage for all that follows. Responsibility and authority must be defined and adhered to. When a plan for a project is put together the responsibility must also be assigned. The senior management must review periodically progress and address any problems. This should be the case for all projects. This review is also useful to meld and synergise projects. QUALITY SYSTEM (ISO 9001 Clause 4.2): A Quality manual that sets guidelines on each of the clauses of ISO 9001 is required. This clearly tells the customer and the work force what the company will do. Quality Planning is critical and will be covered in more detail. Quality plans are the mapping out of what, when and how things will be done, a blueprint for a successful job. DOCUMENT AND DATA CONTROL (ISO 9001 clause 4.5): Documents such as procedures, work instructions and quality records need to be identified and adhered to. This includes documentation on production and materials usage. CORRECTIVE AND PREVENTATIVE ACTION (ISO 9001 Clause 4.14): What to do when a problem arises, not in terms of the solution but in terms of how to arrive at a solution. That is, what resources, who will collect data? Preventative action is about continuous improvement in the process, when information is collated on a job, its successes, problems, unforeseen events. All this experience and information needs to be fed back into the system for incorporation into the process. In Russia, the FMEA allowed for extra time to be budgeted. TRAINING (ISO 9001 Clause 4.18): Training is critical to any process. Traditionally this has been on the job. On the job training is important but must be to a pre-decided process and set of required standards. Often, particularly where technology is being transferred to a third party, this is overlooked or skimped on, in fact many technologies flounder on this basic point. For example, if workmanship, and the methods for achieving it, are not emphasized, (for example squeegee methods are not taught) then such visual surface finishes as joints and turn outs will be poor and the process will look bad and the job will not be durable. This led to more training in these areas for Russian personnel. Most of QA is about management of information. Information is often considered as power and not shared. This leads directly to problems - a segmented approach based on fragmented knowledge. All information is useful and should be assigned to the process via the review function. E.g, in a given job it may be found that if a secondary strike off is used on a particular surface then a better texture is achieved for the final finish. There needs to be a means where objective information on this is conveyed back for inclusion in the process. In VSS this is the foreman's report,but other mechanisms are possible. SPECIAL TOOLS: VSS uses two special tools for determining some of the above data and coming to appropriate decisions. QUALITY FUNCTION DEPLOYMENT: This is to ensure harmony with customer requirements and allows correct processes and process modification to be employed. 
Figure 1 Principles of Quality Function Deployment.
FAILURE MODES AND EFFECTS ANALYSIS (FMEA): A key process is the Failure Modes and effects analysis. (FMEA). The main steps are:
Figure 2 Risk Reduction by FMEA QUALITY PLANS: The main elements of a VSS quality plan are:
APPLICATIOM TO MAINTENANCE CONTRACTS: In New Zealand and Australia (9,10,11) Maintenance contracts are being let to companies who can show a quality program and competence to carry work out. In New Zealand these contracts can be up to 10 years in duration and the company is responsible for all maintenance in a particular area. Major contracts or new construction are still let separately but day to day maintenance is a part of the contract. To be a commercial concern this must be efficient. Efficiency gains expected and largely achieved (9,10) are:
This would appear, combined with warranties on larger jobs to present the best balance for the tax payer and the contractors. However in USA there is considerable work yet to be done. The reader is referred to Kerr (9)and Gallagher (10) for a more complete analysis. CONCLUSIONS: Quality principles may be directly applied to the contracting industry to create the confidence required for customers to pass over responsibilities to the contractor. This requires rigorous development of quality processes and planning. Microsurfacing and other maintenance treatments can be accommodated in this framework. The use of quality principles and tools can create successful outcomes even in very difficult situations (Russia). REFERENCES:
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