Are bitumen rubber & polymer modified binder sprayers different to normal bitumen sprayers – are they calibrated & certified differently? Sprayers are not calibrated differently for different products. Sprayers dedicated to applying Rubber Binders have the following unique features Augers in the bottom of the tank to keep the rubber in suspension. Double heating flues Duty Pumps Larger spray nozzles (35 – 40 l/min) How are road surface types selected, is there a local or national norm, what factors are considered when selecting the given surface? Are there particular treatments used for particular reasons? The type of surfacing is selected based on similar factors as in Australia, traffic volume, road geometry, pavement condition. Other factors include the need to use labour based construction and the local maintenance capability. For example Cape seals may be specified where there is a low level of maintenance expected. Guidance on the use of particular treatment is provided in TRH3 Design and Construction of Surfacing Seals. Is the type of binder to be used included in the selection process or is that determined by the seal design process? The type of binder is a function of the traffic, road geometry and pavement condition and so forms part of the selection process. On national roads this process is undertaken by a consultant appointed by SANRAL who recommends a treatment and provides a basis for the selection. TG1 provides guidelines on the selection of the binder type which should be used. SANRAL only use modified binders on all their seals. Are polymer modified emulsions used in sprayed sealing? If yes what are the key motivators and what are the operational and cost implications? Modified emulsions are used extensively due to ability to be applied in a wider range of climatic conditions and as a SAM treatment. There is a cost penalty which ranges from 10 to 50% extra in comparison to a hot unmodified binder. Does the public sector participate in sprayed sealing (percentage private to public)? This varies between the Provinces, but some still undertake their own sealing on low volume roads. The majority of work is undertaken via contract. Are binders bought in bulk by the client? If yes how is binder allocated to contracts? Generally no however there are instances when a client will purchase directly from a refinery on an ad-hoc basis. Are newer sprayers with different international technologies being used?
With road budgets more constrained than Australia, and with years in which the country was barred from access to international technology and new products, the South African pavement sector has developed quality local expertise. The South African road network has the advantage of was very few subgrades less than CBR10, whether by design of by access to good quality materials. This influences, not only the depths of pavement structures, but types and options available as well This has resulted in a more nationally focused road sector, driven at national level with funding to ensure a commercially aware method of investing in, and managing, the road asset and network. SANRAL, the national road authority is constituted on commercial lines and collects toll funding and receives allocations from the Transport Department. This business awareness is driving the development of a pavement design system more linked to reality and based upon actual material properties and long term pavement performance data. The approach is one of “measuring, modeling and managing” allowing for a knowledge based response to changes in traffic demand, funding or load increases. The approach, linked to service related KRA’s, has assisted the Provinces in having maintenance funds ring-fenced and pavement management tools used as the basis of allocation. Maintenance funds are aimed at “best for asset preservation” which will allow sections of the network to enter terminal states if inadequate funds are allocated for their maintenance. The country has developed skills and expertise ranging from APT and long term pavement performance data collection to comprehensive modeling for pavement design systems. There is encouragement for innovation and new products are subjected to structured evaluation with the goal of achieving a good outcome. In more recent years useful and appropriate international technologies have been identified, such as warm mix asphalt and high modulus asphalt, with the technology jointly transferred by road authorities, researchers, consultants and the asphalt and binder industry. To facilitate the introduction of non-standard products a system similar to the French Avis Technique and the UK HAPAS has been developed to manage and certify the introduction of “fit for purpose” road products. This system has allowed for the development and use of Ultra Thin Friction Courses some of which has been in use for its full product cycle. . Recommendations: Maintain contact with SANRAL on the development of the SAPDM to identify possible advantages for Australia Drive to have road network asset management run on commercial lines or at least on business principles where KRA’s are designed to provide service to the road user and inadequate funding can result in road deterioration or closure.
10:00 am – 4:00 pm Travel Durban to Champagne Sports Resort, venue Sunday 11 September 2011 (continued) 5:00 pm – 9:00 pm Rego and Ice Breaker function Monday 12 September 2011 8:00 pm – 6:00 pm Opening Plenary, Technical Sessions, Workshop Sessions 6:00 pm – late CAPSA’11 Exhibitor’s Braai Tuesday 13 September 2011 8:00 am – 6:00 pm CAPSA’11 Parallel Speciality Sessions, Workshop Sessions 6:00 pm – late Gala Dinner Wednesday 14 September 2011 8:00 am – 5:30 pm CAPSA’11 Parallel Speciality Sessions, Closing Plenary Session 5:30 pm – late CAPSA’11 Social function Thursday 15 September 2011 8:00 am – 1:30 pm Depart venue hotel and undertake N3 inspections with N3Toll Concession representative – crumb rubber manufacture, heavy duty seals and UTFC. 1:30 pm – late Road travel and inspection of construction works to River House Guest Lodge, Malalane. KNP Friday 16 September 2011 8:00 am – 2:30 pm Departed Malalane for the KNP road section headquarters in Sukusa, presentations by KNP and industry binder & seal expert on sand seals and foam / emulsion stabilized bases. Guided site inspections of sand seal and BSM. 2:30 pm – late Travel and inspection of low volume roads in KNP on way to Chestnut Country Lodge, Hazyview. Saturday 17 September 2011 8:00 am – 4:30 pm Departed Hazyview travelling to Phalaborwa through the KNP. 6:00 pm – late Accommodation at Sefapane Lodge, Phalaborwa. Sunday 18 September 2011 11:00 am – 1:30 pm Departed Phalaborwa flying to Johannesburg. 4:00 pm – Flights from Johannesburg to Sydney.