Search results for "Construction"
showing 10 items of 2670 documents
Rheological characterisation of cold bitumen emulsion slurries
2021
The performance of cold bitumen emulsion (CBE) mixtures is strongly linked to an optimised design of the binder blends and mastics. Types and dosages of bitumen, mineral additions and the workability must be characterised and optimised. This study aims at providing an approach for the fundamental characterisation of CBE materials using rotational viscometry. Firstly, a procedure for measuring the viscosity of CBE slurries using the Brookfield viscometer was investigated by comparing results obtained by using a traditional spindle geometry and a novel impeller engineered to avoid phase separation: the dual helical ribbon (DHR). Afterwards, the effect of mineral additions and bitumen emulsion…
A practical approach to estimate the degree of binder activity of reclaimed asphalt materials
2019
Using Reclaimed Asphalt (RA) in new asphalt mixtures can reduce the amount of new material required thereby saving money and natural resources. In addition, asphalt mixtures with RA have shown comparable properties and performance to that generally associated with asphalt mixtures made with 100% virgin material. However, RA content in pavement surface layers is still limited due to specification and technical limitations. For higher contents, the aged RA binder must be analysed to accurately determine the requirements for virgin binders and additives while the degree of blending (DOB) between the RA binder and the virgin binder also needs to be quantified. This is not a simple process and g…
Performance of a sustainable asphalt mix incorporating high RAP content and novel bio-derived binder
2019
The recent drive to find ways to increase sustainability and decrease costs in asphalt paving has led researchers to find innovative ways to incorporate more recycled materials and bio-derived binders into mixes with varying success. A new novel bio-derived binder made from refined pine chemistry stabilised with a polymer can increase the sustainability of asphalt mixes while maintaining pavement performance. Laboratory performance testing was conducted on asphalt mixes containing 50% Reclaimed Asphalt Pavement (RAP) by mix weight and the novel bio-derived binder. Results show that the bio-derived binder outperforms the conventional 50/70 pen grade binder mixes with respect to resistance to…
Intrinsic adhesive and cohesive assessment of the moisture sensitivity of bio-rejuvenated recycled asphalt binders
2019
Alternative binders not derived from fossil fuels, known as biobinders, are opening new paths for multiple applications in road infrastructure. Biobinders, usually produced from bio-oils obtained from the processing of biomass and industry by-products, are tuneable materials whose properties can be adjusted to meet specific targets. For this reason, an interesting approach is to couple biobinders with Reclaimed Asphalt (RA) by taking advantage of their rejuvenating properties to design bio-asphalt mixtures with high-content RA and no additional virgin bitumen. Recent research has proven the feasibility of this approach through validation at full-scale (BioRePavation project). However certai…
The Current and Future Role of Carsharing in Palermo: Analysis of Collected Data and Results of a Customer Satisfaction Survey
2018
In recent years many cities, both in Italy and abroad, have adopted Sustainable Urban Mobility Plans, in which one of the key action is the developing of the sharing mobility. The aim of the paper is to define the role that carsharing plays in Palermo today and it will play in the future, thanks to the adoption of new strategies, such as the introduction of the free-floating system, and transport demand orientation policies, such as the increase in the parking fees for private cars or the expansion of the ZTL. The average user profile of carsharing in Palermo has been identified through a customer satisfaction survey and the potential demand of carsharing in Palermo has been studied using G…
SAFETY CONSIDERATIONS ON TEENAGE PEDESTRIAN-BUS IMPACT
2019
This work studies the impact conditions between the adolescent pedestrian and the bus focusing on head and chest injury. The injury to the head is analyzed using both the Head Injury Criterion (HIC) 36 and the HIC15 parameters as established by the most advanced legislation and comparing the risk probability Abbreviated Injury Scale (AIS3+) and AIS4+. The parameter HIC15 gives a higher probability of risk with lower values, and therefore it can be considered more conservative. Moreover, the study of chest injury is performed with two different biomechanical parameters: the Thoracic Trauma Index (TTI) and the TTI(d); the last neglects the pedestrian mass. The results indicate that the param…
Using UAV Based 3D Modelling to Provide Smart Monitoring of Road Pavement Conditions
2020
Road pavements need adequate maintenance to ensure that their conditions are kept in a good state throughout their lifespans. For this to be possible, authorities need efficient and effective databases in place, which have up to date and relevant road condition information. However, obtaining this information can be very difficult and costly and for smart city applications, it is vital. Currently, many authorities make maintenance decisions by assuming road conditions, which leads to poor maintenance plans and strategies. This study explores a pathway to obtain key information on a roadway utilizing drone imagery to replicate the roadway as a 3D model. The study validates this by using stru…
CAN I TELL JUST BY MYSELF? DISCUSSING A PARENTAL MENTAL DISORDER WITH A CHILD IN A RESEARCH INTERVIEW
2016
In this single-case study, we focus on how to have a dialogue in a research interview with a child whose parent has been diagnosed with a mental disorder. The interactional context and the interviewer’s role in co-constructing the child’s accounts have been largely neglected in the qualitative psychological research on this subject. Stigma related to mental disorders is increasingly being recognized as a central issue for the entire mental health field. It is considered to have far-reaching effects on the social interaction of the stigmatized person and also to contaminate the interactions of those around that person. We examine how the stigma of a parental mental disorder arises and is neg…
Facing a Toxic Object
2021
AbstractOver the past decades, industrial societies have produced a range of substances whose effects humans increasingly identify as toxic—a prominent example is radioactive waste and the question of its disposal. This fabricated “object of modernity” not only calls for the knowledge of the natural sciences, it also affects society at large in its immense challenge of figuring out how to dispose of this material and altogether “detoxify” society from its hazardous activity. The contribution develops a heuristic perspective on toxic objects, exemplified by analyzing documents with a focus on how different societal actors in Germany problematize high-level radioactive waste (HLW) in the cont…
Building teacher identity through the process of positioning
2016
This study explores teacher identity work in the context of a one-year programme, Pedagogical Studies for Adult Educators. The data consist of weekly learning diaries written by Anna, a university teacher, during one academic year. The diaries are analysed by means of dialogically oriented narrative analysis leaning on Bakhtinian notions of voicing and ventriloquation. The results show how Anna positions her storytelling and narrated self in relation to relevant characters by voicing and evaluating these characters. The construct of positioning provides tools for understanding the relationship between the self and others in teacher identity. peerReviewed