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Natural good-quality sources of aggregates are depleting, whereas large amount of reclaimed asphalt pavement (RAP) is produced annually. Safe disposal and use of RAP in the cold in-place recycling (CIR) using foamed bitumen could be sustainable approach where milling and mixing operations are accomplished simultaneously. This will not only help in minimizing contamination (probability) and transportation cost but also reduces the carbon footprints. Therefore, this study aims to investigate the scope of RAP utilization up to 100% and further its effect on the behavior of reclaimed asphalt foamed bituminous mix.

Reclaimed asphalt foamed bituminous mix (FBM) is still a new technique. The evidence of performance of 100% recycled pavement (CIR) is only anecdotal and lacks in systematic guidelines and literatures. Foam binder coating around the aggregates is also a concern. Therefore, this study is mainly emphasized to investigate the scope of RAP use in the FBM up to 100%. RAP content is varied in each trial, i.e. 70, 85, 100 and 0% (only fresh aggregates), to make the FBM. RAP use and its effect on the behavior of FBM in terms of resilient modulus, variation in resilient modulus with curing, rutting performance and the potential of resistance against the moisture damage are addressed.

Considering the laboratory studies, it can be accomplished that mechanistic properties and performance of FBM are largely influenced by RAP material and portray less susceptible characteristics against the moisture damage. FBM containing 70% RAP content exhibits maximum resilient modulus. However, use of RAP up to 100% in FBM is satisfying the minimum required specification.

Overall, the study may be helpful to highway professionals and could generate another possible option of 100% RAP replacing fresh aggregates in the flexible pavements.

Aluminium and its alloys are today widely used engineering materials. They are often used with non‐metallic materials and the following article outlines some guiding rules and principles for preventing the effects of corrosion when aluminium is used with a wide range of materials, including concrete, cement, plaster, soils, timber, adhesives and insulating materials. The application of these principles will go a long way towards minimising the corrosion of aluminium with non‐metals.

Aluminium stearate is a fine, bulky, odourless and colourless powder forming a plastic mass when heated, having the properties both of organic and inorganic matter. It embraces most of the characteristics of other metallic stearates and is regarded as the most important of these. Several studies of the material have already appeared in past years.

Gelation that can occur when copper or aluminium bronze powder is permitted to stand in nitrocellulose lacquer can be prevented by the addition of below one percent of lauric acid. Butyl acetyl ricinoleate will impart highgloss, plasticity, pliability to nitro‐cellulose lacquers and impart permanence, and improves the ageing properties and low temperature flexibility to the product. Acrylic coatings of improved gloss and pattern control have been provided by the addition of methyl hydroxystearate. When barium α‐sulphostearate is added to interior or exterior paints it can produce films of improved hardness. Methyl linoleate can be employed to retard the hardening of Japanese film lacquer. Compositions with good heat stability and good thixotropic properties and which are suitable for use as a base for paints have been evolved by reacting hydrogenated castor oil with toluene di‐isocyanate and emulsifiable and polyethylene wax. The use of aluminium stearate in paints at elevated temperatures can result in films of high opacity, good build, sag resistance, heavy pigmented tolerance and good sealing properties. Myristic acid‐based alkyd aryl ketones have been utilised to impart lustre to wooden surfaces, and stearic acid terminated polyamide/polyimide for coatings for electrical insulators of magnetic wire have been applied to give improved lustre. Diethylene glycol esters of dilinoleic acid can be used to produce non‐drip paints, as can ethylene diamine bis hydroxystearate, and glyceryl trihydroxystearate. Hydrogenated castor oil is useable in the making of thixotropic agents applicable to paints have been prepared from the material, plus oligomers of hydroxystearic acid/ethylenediamine/sebacic acid polymers. Ethyl linoleate and ethyl linoleate have been used as penetrants in anti‐corrosive paints based upon alkyd resins. Aluminium stearate can prevent excess penetration by paints of surfaces. Bis (hydroxymethyl) propanediol oleate has found use in alkyd resins derivative coatings with butylated melamine resins‐hardening materials to give pinhole resistant coatings. Butyl stearate is a good low temperature plasticiser for paints. Butyl acetyl ricinoleate imparts good plate release and cold crack resistance to leather lacquers, and provides good handle and excellent low temperature flexibility to coated fabrics on thick unsupported sheetings.

The Secretary of State after consultation with the Ceramics, Glass and Mineral Products Industry Training Board and with organisations and associations of organisations appearing to be representative respectively of substantial numbers of employers engaging in the activities hereinafter mentioned and of substantial numbers of persons employed in those activities and with a body established for the purpose of carrying on under national ownership an industry in which the said activities are carried on to a substantial extent and in exercise of her powers under section 9 of the Industrial Training Act 1964(a) and of all other powers enabling her in that behalf hereby makes the following Order :—

Refractory Coatings. A new range of refractory protective coatings is being manufactured under the name of Coltrate R.P.C. There are several types to deal with varying conditions, and they are all supplied in the form of a dry powder. To prepare for use, the powder is mixed with water to a thick, creamy paste and applied by brushing, spraying or trowelling to give a coating thickness of 1/16 in. to ⅛ in. After application, the furnace is fired and the temperature steadily increased up to the point where vitrification is reached.

ITALY Coating of metal with polyethylene. Polyethylene shows no particular degree of adhesiveness on metal surfaces. The following technique alone will give satisfactory results: an intermediate layer of polyvinyl alcohol or polyvinylformal or polyvinylbutyral is sprayed on with a flame spray gun, forming a crinkly coat. As soon as this undercoat has been applied the first polythene coat is sprayed on. This will homogenise the intermediate layers and give a smooth and even coat. The intermediate layer is sprayed on by blowing 80 to 100 g. of polyvinyl‐acetate powder per sq. m. of surface through a flame gun. The polythene is then applied in one, or preferably more, coats. Dry air is an excellent carrier for the powders, and the gun is operated with propane or hydrogen. —(G. Guzette, Ind. Vernice, 7 (12), 319–320.)

Mr Henry Sonneborn III President of the Witco Chemical Corporation of the USA made a recent visit to the Droitwich plant of Witco Chemical Ltd, the UK subsidiary of the Group. During his visit, he was shown the new metering and mixing equipment for the producton of blended polyester resin — Witcothane. Commenting on his trip to the UK, which incorporated visits to France and Holland Mr. Sonneborn said “It is pleasing to note that there is an upturn in the European Chemical Industrial Trade. If we are to preserve a buoyant and vital marketing environment it is up to us, the producers, to keep a constant watch on technological developments. The new equipment at Droitwich is a fine example of just such technology.”

A new range of self‐seal polythene, box‐type, stable stacking sacks for the machine filling of powder and granular materials, from Palagan Limited, carry a price tag which reflects a cost saving innovative design.

The parameters for Quality Control of both the anti‐corrosion coating and, where required, concrete weight coaling, are reviewed for six major pipelines in which the authors have been directly involved. The importance of field joint anti‐corrosion coatings are discussed, particularly for concrete weight coated pipelines. The differing environment of each project is identified and includes “in‐service” temperature, water depth, mode of pipe lay, together with cathodic protection considerations. The importance of quality control is traced from initial design study to coating and includes practical aspects of on‐site quality assurance. Material selection, application, inspection, safety aspects and economics are discussed.