The conical air-void structure of an InGaN light-emitting diode (LEDs) was formed at the GaN/sapphire interface to increase the light extraction efficiency. The fabrication process of the conical air-void structure consisted of a dry process and a crystallographic wet etching process on an undoped GaN layer, followed by a re-growth process for the InGaN LED structure. A higher light output powe...

The air void analyzer (AVA) was used to study the effects of concrete materials and mixing procedures on air void characteristics of fresh concrete. Twenty-seven batches of concrete were prepared with three mixes (with and without fly ash or water reducing agent), five mixing procedures (one-step mixing for one, two, or four minutes, two-step mixing for four minutes, and ASTM standard lab mixin...

A new database called AC/k-1624 containing over 1600 measurements of saturated hydraulic conductivity asphalt concrete has been assembled and analysed. was used to investigate the effect grading entropy parameters on conductivity. prediction model comprising both air voids is presented. The analysis using different predictors reveals that gradation does affect conductivity, but void level neces...

It is well known that the performance of hot mix asphalt (HMA) in service life is closely related to a proper aggregate gradation. A laboratory study was conducted to investigate the effects of nominal maximum aggregate size (NMAS) on the performance of stone matrix asphalt (SMA). The volumetric characteristics and performance properties obtained from wheel tracking tests, permeability test, be...

Surface hot-in place recycling of asphalt mixtures has been conducted on Finnish roads for several years. The procedure is performed either in full-lane ('remix') or shorter widths ('rut-remix'). In a 2020–2021 project, different mixture types were subjected to both kinds recycling; reference mixtures, and modified with aramid fibres, FEP elastomer pellets, polymer, Storelastic rubber additive,...

Ultrasonic testing can be used for a nondestructive and rapid determination of material properties. In this study, twelve asphalt mixture samples four different types were fabricated in conventional property tests two ultrasonic wave tests. Physical properties such as bulk specific gravity air void content, mechanical dynamic modulus phase angle, acoustic velocity measured. Relationships betwee...

Sustainability is providing the needs without compromising ability of strategical forming to meet their requirements. The production warm asphalt mixtures using recycled pavements produces economic and environmentally friendly mixtures, which most important advantage this work. This research aims determine effect concrete (RAP) on indirect tensile strength Marshall Properties. Models Aggregate ...

Moisture is a significant problem in standard pavements, causing asphalt mixtures to deteriorate due insufficient water permeability. This failure from moisture damage often caused by precipitation accumulation or poor drainage, which allows weaken adhesion seeping between the aggregates and asphalt. The relationship permeability aggregate contact length believed be inverse. To effectively asse...

The bonding between pavement and a steel bridge deck is key component affecting the structural integrity of delamination major cause. interface was systematically investigated to evaluate interactive influences factors, such as air void asphalt concrete pavement, surface roughness deck, thickness zinc-rich epoxy primer, waterproof membrane, on bond strength interface, through simulated loading,...