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Parametric Study and Optimization of Parameters in Powder Mixed Wire-EDM Using Taguchi Analysis
Published in Satya Bir Singh, Prabhat Ranjan, Alexander V. Vakhrushev, A. K. Haghi, Mechatronic Systems Design and Solid Materials, 2021
Swarup S. Deshmukh, Arjyajyoti Goswami, Ramakant Shrivastava, Vijay S. Jadhav
Despite rapid technological advancements in the field of conventional machining processes, the machining of carbides and other hard-to-machine materials has been limited to the diamond wheel grinding for a long time. Diamond grinding is not a cost-effective process since diamond grits are not readily or cheaply available. Also, the industries of aviation, automobile, and marine made very rapid progress, which resulted in them using different alloys of materials. Such high-strength-temperature-resistant (HSTR) alloys cannot be processed through conventional means. The required shapes and sizes of the machined component are becoming increasingly complex such that conventional methods of machining are either too time-consuming or are entirely incapable of generating such parts. Thus, neither the conventional techniques of machining are in a position to meet the challenges posed by the new development of materials nor is there any greater scope for further development. Therefore, it is clear that some new strategies of machining must be developed in order to deal with the challenges created by the development and use of the hard-to-machine and high strength temperature resistant alloys.
Low-noise road surfacing
Published in S.E. Zoorob, A.C. Collop, S.F. Brown, Performance of Bituminous and Hydraulic Materials in Pavements, 2017
Some of the materials that may meet these criteria are:Exposed aggregate concrete (with longitudinal smoothing beam).Diamond grinding concrete (3 mm wide, parallel, longitudinal grooves in hardened concrete).Porous asphalt.Porous concrete (with additives to enhance mechanical properties).Thin asphalt surfacing.
Life cycle cost analysis of runway reconstruction alternatives for commercial service airports
Published in Andreas Loizos, Imad L. Al-Qadi, A. (Tom) Scarpas, Bearing Capacity of Roads, Railways and Airfields, 2017
Table 1 also identifies Direct Construction Costs with the value of Base or Base plus 20%. These comparisons are for items that contribute to the construction cost but are roughly equal for these individual cases. Diamond grinding is a process used after concrete construction to reduce high spots in the pavement to smooth the surface. Diamond grinding for Case 1 would be normal, but for Case 3 since construction occurs at night on a short length of construction more diamond grinding would be expected. However, Case 2 would not have diamond grinding but may have some spot milling.
Effects of partial replacement of fine aggregates with crumb rubber on skid resistance and mechanical properties of cement concrete pavements
Published in International Journal of Pavement Engineering, 2022
Ali Raza Lashari, Yasir Ali, Abdul Salam Buller, Noor Ahmed Memon
One important characteristic of rigid pavements is skid resistance, which has been reported to affect significantly traffic safety (Fenech 2000). Skid resistance is often described as the friction between tyre and road surface required to balance driving forces and safe stopping/braking. This resistance is a function of surface texture of a pavement, which can be either micro or macro. These two collectively deal with individual aggregate shaping the road surface and is responsible for controlling the contact between tyre rubber and pavement surface. Li et al. (2016) analysed surface texture and friction characteristics of diamond-ground concrete pavements and reported that diamond grinding produces longitudinal, continuous, and line-type texture that contains corrugations with evenly spaced ridges, which enhances pavement surface friction. In another study, grooving was applied to improve skid resistance performance of concrete pavements and reported the benefits of pavement grooving in improving the skid resistance during wet pavement conditions and reducing the risk of hydroplaning (Pasindu et al.2012). Recent research has shown that rigid pavements often experience skid resistance issues with increasing age because of cement paste loss (Rith et al.2020). For instance, a recent study (Gierasimiuk et al.2021) has used various texture improvement techniques and found that exposed aggregate concrete outperformed other techniques in enhancing skid resistance. Another study (Fang et al.2020) reported that polymer-modified cement-concrete paste lower noise levels and can enhance skid resistance.
Influence of texturing method on tyre/road noise of cement concrete pavement
Published in International Journal of Pavement Engineering, 2018
Wladyslaw Gardziejczyk, Pawel Gierasimiuk
In recent years, pavement texturing has been performed using the diamond grinding method. Diamond grinding is mainly used to improve both skid resistance and evenness of concrete pavement. Diamond saw blades are used in this method, which are placed one next to another (from 164 to 197 blades on a width of 1 m), making grooves from 3 to 20 mm in depth. According to (National Concrete Pavement Technology Center 2011d) the depth of grinding with the diamond blades should not exceed 19 mm in relation to the starting pavement. This results in a so-called positive texture. The aim of this method is to make small grooves which provide better tyre/road contact, lower the sound level and help with better dispersion of water from road surface (Rasmussen et al.2012).