1,721,080 research outputs found
Comparing Light Weight Deflectometers to standardize their use in the compaction control
No full textAlong with the increase of road traffic and loads, arises the need for a methodology for studying and predicting the rutting resistance of asphalt concretes. The growth of this phenomenon on the asphalt pavement is directly connected with the layers’ structural damage and it is reflected in terms of safe riding. An accurate laboratory characterization of the material rutting performance is desirable, aiming to reduce the distresses during its lifetime and to predict the mixture tendency to develop excessive permanent deformations under repeated heavy traffic loading.
This paper reports a case study concerning the evaluation of the mechanical characteristics of two Warm Mix Asphalts (WMA). A unique binder type was adopted to reduce the number of variables, since it is known that one of the primary cause which engender the rut distress is the plastic behavior of the binder. These analysis were carried out with different tests setup complying with the EN 12697-25 requirements, varying stress level, but keeping constant temperature, loading type and time
Early life field performance of innovative sustainable semi-flexible pavements
No full textSemi-flexible pavements in heavy loads areas are recommended to guarantee good perfor- mance and safety. They are usually constructed by placing a wearing layer of grouted mac- adam, a composite material consisting of a porous Hot Mix Asphalt (HMA) skeleton grouted with a cementitious matrix. However, its use is limited as the production process is quite complex and laborious. An effective alternative to grouted macadam can be represented by the Ready to Mix (RTM), recently implemented to offer performances comparable to those of the grouted macadam and a most effortless put-in-place process, and contemporarily leading to environmental and economic advantages. The present research investigated the early life field performance of a semi-flexible pavement including an RTM base. Three Falling Weight Deflectometer testing campaigns were carried out from 2017 to 2021. In particular, the semi-flexible pavement was compared to a reference flexible pavement entirely made with HMA in terms of temperature sensitivity as well as bearing capacity
Studio e controllo di pavimentazioni stradali a bassa emissione sonora in ambito urbano
No full textRapporto di ricerc
Dynamic field assessment of bearing capacity for pavement subgrades and foundations
No full textIn situ assessment of bearing capacity is usually performed by means of static plate loading tests. Today, however, higher performance dynamic investigation methodologies are increasingly often employed, in combination with traditional and deflectometric techniques. This allows a large amount of data to be recorded rapidly, thereby guaranteeing more detailed investigation, but also making the process of data elaboration and result interpretation more time-consuming. In the present study, an improvement in data elaboration techniques and interpretation of results was achieved through application of geostatistical science to measurement and analysis of data acquired at several experimental sites. The findings suggest that geostatistics-based systems have the potential for use as quality control/quality assurance (Qc/Qa) devices in testing subgrades, subbase courses and compacted soil layers and as a means of evaluating their correspondence to the strength performances required for the layers. Concomitant use of various deflectometric systems also made it possible to take specific construction and operating characteristics of the devices into account when evaluating the experimental results. This paper reports on joint experiences conducted by the Universities of Pisa and Bologna, whose research teams have long been working on validation of innovative field testing systems. The results appear promising for upcoming insertion of the methodologies inserted into existing technical specifications
Evaluation of cement treated mixtures with high percentage of reclaimed asphalt pavement
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
