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The interest in waterborne coatings continues, and this trend is well‐demonstrated by many new proprietary products. For example, a new acrylic latex enamel has been announced which has high gloss and superior colour retention. Associated with the product are the usual properties of easy application, low odour, and water cleanup. The product is available from the O'Brien Corp. [450 E. Grand Ave., So., San Francisco, CA 94080].

The purpose of this paper is to develop an improved adhesion model to better reproduce the low adhesion condition of the anti-skid control for rail vehicles under braking condition.

In view of the low adhesion characteristics for rail vehicles under braking conditions, the Polach adhesion model was improved based on the sliding power and sliding energy. The wheel–rail low adhesion model suitable for braking condition was given. The analysis of braking anti-skid control under emergency braking condition was carried out through the co-simulation, and compared with the test data; the effectiveness and practicability of the improved low adhesion model were verified.

The results showed that the improved adhesion model is simple and efficient and the parameters involved are less, and it can be directly applied to the real-time simulation of anti-skid control in the process of train braking.

This paper can provide a theoretical reference for the reasons of change and improvement of adhesion between wheel and rail caused by the adjustment of braking force under anti-skid control, which can fulfill a need to the study of sliding energy on the contact surface, the removal effect of pollutants on the wheel–rail surface and the improvement and recovery of adhesion caused.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2020-0244/

A new sound level indicator is now available from Dawe Instruments Ltd., Western Avenue, London, W.3, to provide quick and reliable readings of noise.

Protecting off‐shore splash zones from corrosion presents special problems, not the least of which is the task of applying coatings in‐situ. The hazards include:

New primers The desire to inhibit corrosion motivates continual research on primers.

TAKE‐OFF performance requirements for transport category aircraft have been the subject of many technical discussions and conferences and having taken into account the opinions and suggestions of many interested parties, the FAA have decided to add new standards for approval of a reduced take‐off decision speed (V1) methodology. This would be for take‐off on wet and precipitation contaminated runways and it is considered that the proposal to lower V1 by allowing a reduced clearance over the end of the runway (screen height) would provide an increase in safety for rejected take‐offs on wet and contaminated runways.

This study aims to investigate the influence of surface texture distribution in respect to the procedure of pavement surface wear on friction performance.

The Weierstrass–Mandelbrot (W-M) equation is used to appropriate pavement surface profile. Through this approximation, artificial rough profiles by combining fractal parameters and conventional statistical parameters for different macro-texture are created to simulate the procedure of pavement surface wear. Those artificial profiles are then imported into discrete element model to calculate the interaction forces and friction coefficient between rolling tire and road. Furthermore, wavelet theory is used to decompose the profiles into different scales and explore the correlation between the profiles of each scale and pavement friction.

The influence of tire vertical displacement (TVD) on friction coefficient is greater than fractal dimension of road surface texture. When TVD decreases, the profiles can provide higher friction, but the rolling stability of tire is poor. The optimal fractal dimension of road surface is about 1.5 when considering friction performance. The pavement friction performance improves with wavelength from 0.4 to 6.4mm and decreases with wavelength from 12.8 to 51.2mm.

Artificial fractal curves are generated and analyzed by combining W-M function with traditional parameter, which can also be used to analyze the influence of texture distribution on other pavement performance. The preliminary research provides a potential approach for the evaluation of pavement friction performance.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2019-0499/

Closely related to coatings are the patching and caulking materials which are important in proper maintenance of many structures. A new product known as Roof and Gutter Patch has been introduced by Southern Protective Products Company [P.O. Box 10888, Atlanta, GA 30310]. The product is based on butyl rubber and can seal joints, seams, and cracks in galvanised metal, aluminium, or vinyl‐clad gutters, troughs, and downspouts. It can also be used to repair roofing, flashing, and chimneys, and to reseal asphalt shingles. The product is said to maintain a tough, pliable bond for years and may be coated with either oil or latex paints.

New Waterproof Tape. The manufacturers of Permacel pressure‐sensitive tapes have succeeded in combining strong cotton cloth with a revolutionary water‐proof backing material. This has enabled them to produce a complete new waterproof cloth tape.