SETTLEMENT MODELLING OF THE CA\u2019 ROSSA LANDFILL IN A POST-CLOSURE PERSPECTIVE

Ca' Rossa landfill is located in the southern part of the Venice lagoon. Transfer of MSW into the landfill has been over since 2009. The management company has been waiting for the development of further waste settlements, before providing for the final cover system. This paper presents an analysis of settlements due to compressibility of natural soils, underlying the landfill, and of wastes. The study was carried out through analytical and numerical methods using as input data periodic topographic levelling of the landfill and geotechnical parameters of soils, derived from previous laboratory and in-situ tests. By comparing expected and actual settlements, a calibration of the original input data was possible. These corrected values were finally implemented in a finite element model in order to estimate the future landfill settlements

What differentiates future entrepreneurs? Developing entrepreneurial competencies in higher education

Research in the field of entrepreneurship has contributed to determine what personal characteristics enable certain people to engage in a new venture creation. Among these intrinsic factors that distinguish entrepreneurs from non-entrepreneurs, emotional, social and cognitive competencies (ESCs) may have a positive impact on discovering, evaluating and exploiting entrepreneurial opportunities. Prior studies primarily focused on these competencies possessed by adult entrepreneurs and on their impact on firm performance, neglecting their development process especially in young people. The aim of our research is to contribute to fill this gap by understanding what favors the development of emotional, social and cognitive competencies in graduates who express an entrepreneurial intent. We address the following questions: do graduates who will to start their own venture present a different ESCs profile than those who do not express this intent? What factors favor the development of ESCs? ESCs received a great attention in the management literature especially in the field of leadership. Prior research shows that ESCs affect the pursuit of entrepreneurial initiatives and their performance. However, literature devoted a limited attention to the role of ESCs in affecting the formation of an entrepreneurial intent and to the factors that impact on ESCs development. We carried out a study on two groups of Italian young graduates who participated in a two-week program concerning the assessment of their ESCs within two different cycles of seminars. The participants enrolled in these cycle of seminars were at the end of their academic experience or had recently graduated. One cycle of seminars was delivered to participants who expressed the intent to become entrepreneurs and provided them knowledge and skills on new venture creation, whilst those who participated in the other learned some general techniques to enter into the labour market. This study tests the hypothesis that the emotional, social and cognitive competencies of the two groups of participants are different. We measured the differences from the multisource feedback which was provided to students based on a survey instrument, namely the Emotional and Social Competency Inventory. Findings show the difference in the competency profile of the two groups of participants and provide evidence on the relationship between students’ learning experience, such as work, social and international background, and the possession of ESCs. These results add to the debate on how emotional, social and cognitive competencies can be promoted in the context of entrepreneurship education, in order to support students in their entrepreneurial career decision. This paper suggests an approach to evaluate and compare competencies between students who express different professional intents. It also takes into account their antecedents for a future entrepreneurial career

Stress increase induced by impact precast pile driving

The paper describes the experimental activities carried out in a test site, set up to evaluate the increase of soil stiffness and horizontal effective stress, mainly in saturated low-medium density sandy layers and in silty sand, after the driving of tapered precast piles. The experimentation consisted in driving some prefabricated tapered piles with different energies and spacing between them in an area where some soil layers had a high liquefaction potential. To evaluate the pile driving effects on the stress state around them, preliminary CPTu and DMT tests were carried out and repeated after the driving activity. In particular, the change of the CPTu sleeve resistances was compared with that of the DMT KD data, to evaluate the increase in horizontal stress using different methods, a phenomenon influencing the soil susceptibility to liquefaction and the pile bearing capacity

Leadership style scale: Conceptualization and initial validation

This paper describes the development and validation of a scale to measure leadership styles that lead to resonant or dissonant organizational environment. Differently from other scales that focus their attention on one specific style, we offer a holistic approach that considers a broader range of behaviours. Based on theory, a pilot study, and questionnaires, we developed a tool to assess six styles of leader behaviours (Inspirational, Supportive, Aggregating, Democratic, Demanding, and Authoritarian). We tested the model in a sample of students and practitioners. We also run a non-parametric test that confirms that resonant styles of leadership have a positive impact on projects’ performance. The results supported the validity and reliability of the six-dimensional items. We thereby contribute to the literature by providing a practical tool of 36-item instrument, labelled the Behavioral Leadership Styles Evaluation (BELEADER) Questionnaire

Experimental Acceptance Procedure for Using Cullet in the Gas Collection Layer of MSW Landfill

The multilayer system of a non-hazardous solid wastes landfill cover, required by most international regulations, includes a granular layer of adequate permeability and thickness for the collection and drainage of biogas. The choice of the most suitable material generally falls on granular soils, containing very low percentages of fines. The paper presents the possibility of replacing natural soils with cullet, obtained by the glass shredding, and widely available on the market. Its hydraulic conductivity with regard to biogas and its granulometric compatibility with the adjacent layers may be initially assessed by means of the usual filter design criteria. Then, its crushing strength, under static and cyclical loads, must be evaluated, since the capping systems are crossed by heavy earthmoving trucks, and consequently, there is the possibility of a change of the cullet granulometric distribution. As cullet is not a conventional material, the usual geotechnical laboratory tests cannot be directly applied to it. The paper suggests an innovative laboratory procedure, defined as a static and cyclical punching test, which allows to evaluate the crushing resistance of cullet by using the traditional apparatus for soil compaction

A New Approach for the Design, Construction and Control of Compacted Mineral Liners of a MSW Landfill Capping

Design parameters typically used for the mineral liner of landfill cover system (e.g. water content w, dry density ρd and hydraulic conductivity k) are often difficult to obtain on site. After construction, these experimental parameters need to be checked against the predicted values. In this paper, a rigorous procedure for design, construction and control of a compacted mineral liner in a capping multilayer system has been developed. The procedure has been schematically subdivided in three phases. The first phase (design) was based on a wide preliminary set of laboratory tests, composed of classification, compaction and permeability tests. An analytical relationship among degree of saturation Sr, dry density ρd and hydraulic conductivity k is also defined. The second phase (construction) was developed through a suitable compaction of the mineral liner planned after the design phase. The last phase (in-site control) consists of checking the design parameters (w, Sr, ρd, k) actually achieved on site. A comparison between coefficients k, obtained through site permeability tests and an analytical relationship obtained in the design phase, was made successfully. Owing to this new approach, it will no longer be necessary to perform in situ permeability tests, but it will be enough to define the above-mentioned analytical relationship during the design phase. In this way, a dangerous damage to the mineral liner, caused by the execution of invasive permeability tests, will be also avoided