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An investigation of clay microstructure and its evolution under 1D and isotropic compression is presented for different clays. Data from the literature are compared to original results on two Italian clays, obtained using SEM, image processing, MIP and on-purpose swelling tests. The effects of composition and loading history on clay microstructure, as well as its changes along the compression path (pre- and post-gross-yielding) are analysed and a conceptual model of microstructure evolution is proposed for the clays under study. NC clays at early virgin compression, either natural or reconstituted, are found to possess an open fabric of random-low orientation, complying with a prevailing inter-aggregate and a smaller intra-aggregate porosity, whose size and distribution depend on composition. Under 1D compression, either in the field or in the laboratory, the inter-aggregate porosity is lost, at a rate dependent on composition and loading history, and the dominant intra-aggregate micro-pore is progressively reduced. Accordingly, perfectly oriented stacks of domains are recognised which, though, embed preserved random particle arrangements even at large pressures, resulting in an increase of average orientation up to the reach of a steady orientation degree. Isotropic compression causes faster microstructure evolution, although large pressures are required to change 1D-induced fabric orientation., Peer Reviewed, Postprint (author's final draft)

Part of a research programme concerning the investigation of the evolution of clay microstructure under different loading paths is presented. The material is a stiff over consolidated natural clay, strongly bonded by diagenetic processes. Its one-dimensional compression and consequential microstructural changes are compared with those of the same clay when reconstituted. The microstructural changes are evaluated using scanning electron microscopy. The results of oedometer tests are discussed, some carried out in a purpose-built constant-rate-of- strain oedometer which enables the behaviour of the natural clay to be studied well beyond yield. The variations in swelling index, stiffness and coefficients of consolidation and permeability are compared pre- and post-yield for the two clays. Both clays are found to have significantly different states and fabrics at all stages of compression. Post-yield the structural changes in the natural clay are initially a destruction of the original fabric, and then a rearrangement of the clay particles into a systematic packing of honeycomb and perfectly oriented fabrics. The same fabric architecture is recognized at medium magnification in the reconstituted clay compressed to high pressures. Despite the different states and structures of the two clays, the trends of compression and consolidation behaviour are found to be similar., The Authors thank the Italian Ministry for Research and University (PRIN 2015 grant, Prot. 201572YTLA) for supporting the research. The research activity has been carried out with the contribution of Fondazione Puglia., Peer Reviewed, Postprint (published version)

An investigation of the microstructural features of a high-plasticity clay, in both its natural conditions and reconstituted in the laboratory, is described. Scanning electron microscopy is used here to characterise the fabric at different magnifications, while image processing of the micrographs delivers a quantitative assessment of the fabric orientation. The results of energy-dispersive X-ray spectroscopy and swelling tests, as reported in a previous study by the authors, are used to characterise the bonding nature and strength, as well as mercury intrusion porosimetry to investigate clay porosimetry. Despite their identical composition, the natural and the reconstituted clay have experienced different deposition and loading history, generating different microstructural features that are shown to underlie their differences in state. For both clays, one-dimensional (1D) compression to medium–high pressures is seen to determine a well-oriented medium magnification fabric. However, larger-scale observations and the corresponding image processing results reveal non-uniform local fabric features, hence making fabric characterisation dependent on the scale of analysis and bringing about the issue of identifying the clay micro-scale representative element volume relating to the clay macro-behaviour. The micro-REV is identified for the clays under study and its connection with the macro-behaviour characterised. The microstructural evolution induced by 1D compression to very high pressures is shown to concern mainly the clay porosity and porosimetry, the fabric orientation being steady, thus explaining the isotropic hardening observed in laboratory tests., Peer Reviewed, Postprint (author's final draft)

Purpose: The purpose of this paper is to understand the process that occurs within public employment offices (PEOs) and its consequences for unemployed people. Specifically, it analysed some practices needed to implement activation programmes developed in some PEO in Lombardy (Italy) and the role of front-line officers, promoting a dialogue between the literature on activation policies on one hand and the literature on street-level bureaucracy on the other. Design/methodology/approach: The fieldwork has been conducted in Lombardy, which is one of most economically developed areas both in Italy and in Europe. The empirical research integrated quantitative and qualitative research tools; specifically a CATI survey of 994 persons; participant and non-participant observations, semi-structured interviews, and an analysis of documents in four PEOs. Findings: The paper describes and analyses both practices needed to implement activation programmes and the perceptions of the social actors (unemployed people and front-line officers) who build and address these practices daily. Specifically, the attention is focussed on the different forms of discretion used by PEOs’ front-line officers and a mix of technical, relational and psychological support received in the PEOs. Moreover, the authors noticed that the front-line officers’ discretion seemed to be more limited in those parts of the activation process in which it should be more relevant, that is, the identification of training courses aimed at increasing unemployed workers’ skills. Notwithstanding these limits, many users expressed positive opinions of these courses, which could be explained by secondary functions of training courses. Research limitations/implications: The qualitative portion of the fieldwork has limited generalisability because it focussed on few PEOs. Practical implications: The findings are relevant to policy makers who deal with activation policies and to public and private organisations that implement

The paper focused the attention on the public employment services (PES) in Lombardy, one of the more economic-advanced Italian regions. Historically the Italian public employment offices (PEOs) have been perceived more as a place for getting economic relief than for getting a job (suffering - as the literature has shown – the label “dole-queue-image”). In order to change this situation some relevant reforms concerning the PES (and PEOs) have been promoted in Italy in the last 20 years, but the results are very fragmented: in some regions (such as Lombardy) there was a broad application of the reforms (with different outcomes), in other the application was more poor. Moreover, during the recent economic crisis, PEOs have dealt with new challenges concerning both the increase of unemployment rate and changes in the nature of unemployment. At the same time, PEOs have had to manage some provisional anti-crisis measures, which combine, for the first time in Italy, passive labour market policies (several schemes of unemployment subsidies) with active policies (training schemes and various services such as tutoring and coaching). In this situation we have analysed how public employment offices have been perceived by people who usually hang out at them daily, i.e. unemployed persons and front-line workers of the PEOs. Different findings have arisen from the empirical research. In particular, in this paper we focus the attention on the relations between unemployment workers/users of PES and front-line workers of the public employment offices, on their perceptions of the PES and on relational processes that contribute to the shift from unemployed person to person who is ready to look for a job. The analysis of collected data and information points out a paradox: even if PEOs seem to confirm its image of place where it is easier to get economic reliefs rather than getting a job, the users of PES have declared a medium-high level of satisfaction for the services they used. Empi

Effetti negativi sull’occupazione causati dalla crisi economica si stanno verificando anche in aree caratterizzate per lungo tempo da alti tassi di impiego, quali la regione Lombardia. Questo articolo indaga alcune delle conseguenze della perdita del lavoro sul benessere economico e soggettivo di lavoratrici e lavoratori autoctoni e stranieri, che risiedono in Lombardia. L’indagine empirica ha mostrato differenze fra le due categorie: in particolare, per i lavoratori stranieri la disoccupazione prolungata dovuta alla crisi sembra incidere in maniera rilevante su molteplici dimensioni della vita, generando situazioni di precarietà diffusa e, in alcuni casi, producendo conseguenze negative nel percorso migratorio. Dall’indagine sono però emersi fattori, come ad esempio l’età e le reti sociali in cui un soggetto è inserito, che sembrano creare nuove segmentazioni trasversali alle categorie autoctono e straniero.