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During an explosive eruption, a construction is hit by several actions, always associated to elevated temperatures, causing fires, possible explosions and reduction of the mechanical properties of the structural materials. In this paper the attention is focused on the analysis of a specific volcanic event, the so-called air fall deposits, generally falling from the eruptive column due to gravity. The study, starting within the European COST Action C26 project “Urban habitat construction under catastrophic events” (2006-2010), is concerned with the Vesuvius area at Naples in Italy. It faces two important aspects. The first items the proposal of a model for the air fall deposits action on the basis of a similitude with the snow load. The second item is the robustness evaluation against the air fall deposits of the most common roof types in the Vesuvian area, which are made of timber, steel and reinforced concrete. Therefore, some protection systems for mitigating the effects of the combination of overloading and high temperatures on the examined roofing structures are identified.

This article sets out to address the response of traditional societies in facing natural hazards through the lens of the concept of resilience.

This paper considers that resilient societies are those able to overcome the damage caused by the occurrence of natural hazards, either through maintaining their pre‐disaster social fabric, or through accepting marginal or larger change in order to survive. The discussion is based on a review of the corpus of case studies available in the literature.

The present article suggests that the capacity of resilience of traditional societies and the concurrent degree of cultural change rely on four factors, namely: the nature of the hazard, the pre‐disaster socio‐cultural context and capacity of resilience of the community, the geographical setting, and the rehabilitation policy set up by the authorities. These factors significantly vary in time and space, from one disaster to another.

It is important to perceive local variations of the foregoing factors to better anticipate the capability of traditional societies to overcome the damage caused by the occurrence of natural hazards and therefore predict eventual cultural change.

This article takes off from the previous vulnerability‐driven literature by emphasizing the resilience of traditional societies.

The purpose of this paper is to explore how culture, including traditions and social structures, can influence resilience and how culturally sensitive relief operations can put affected people and their context at the core of any interventions.

A case study of the Mt Sinabung volcano area in Indonesia was undertaken. As part of the case study, an analysis of interventions was conducted, which was complemented by semi-structured interviews with Karo cultural experts and humanitarian organisations.

Culture influences the manner in which the Karo people react to volcano eruptions with varying implications for recovery. In addition, relief organisations which understand people’s actions through a cultural lens have better managed to tailor programs with long-term impact, thereby avoiding aid dependency.

Practical examples of disaster management activities that adequately account for the beneficiaries’ way of living prior to the eruptions are provided. Aid actors are provided with guidance concerning how to better tailor their activities in line with a cultural lens.

The study provides empirical grounding for claims concerning the role of culture in planning interventions in Indonesia and other similar contexts.

The corrosive attack of boiler surfaces exposed to flue gases has occurred from time to time in plant operated by the Central Electricity Generating Board. The availability lost in this way is little more than 1% of the total boiler capacity installed, but when the load demand is met mainly by unit generators with a steaming capacity over 100 MW, the enforced shut‐down of one of these units would be a more serious loss. This article describes the ways in which various parts of boilers are attacked, the factors affecting corrosion in these cases and the chemical basis of the processes. Investigations are being carried out, and several preventive methods are mentioned.

IN an article published in the February issue of AIRCRAFT ENGINEERING the writers discussed the influence upon lubrication of various physical and chemical characteristics of lubricants, practicable and otherwise.

The processing techniques and materials utilized in the fabrication of a two-terminal electrostatically actuated micro-electro-mechanical cantilever-arrayed device used for radio frequency tuning applications are presented in this work. The paper aims to discuss these issues.

The process, which is based on silicon surface micromachining, uses spin-coated photoresist as the sacrificial layer underneath the electroplated gold structural material and an insulating layer of silicon dioxide, deposited using plasma enhanced chemical vapour deposition (PECVD), to avoid a short circuit between the cantilever and the bottom electrode in a total of six major fabrication steps. These included the PECVD of the silicon dioxide insulating layer, optical lithography to transfer photomask layer patterns, vacuum evaporation to deposit thin films of titanium (Ti) and gold (Au), electroplating of Au, the dry release of the cantilever beam arrays, and finally the wafer dicing to split the different micro devices. These process steps were each sub-detailed to give a total of 14 micro-fabrication processes.

Scanning electron microscope images taken on the final fabricated device that was dry released using oxygen plasma ashing to avoid stiction showed 12 freely suspended micro-cantilevered beams suspended with an average electrostatic gap of 2.29±0.17 μm above a 4,934±3 Å thick silicon dioxide layer. Preliminary dimensional measurements on the fabricated devices revealed that the cantilevers were at least 52.06±1.93 μm wide with lengths varying from 377.97±0.01 to 1,491.89±0.01 μm and were at least 2.21±0.05 μm thick.

The cantilever beams used in this work were manufactured using electroplated gold, and photoresist was used as a sacrificial layer underneath the beams. Plasma ashing was used to release the beams. The beams were anchored to a central electrode and each beam was designed with varying length.

Dutch power companies recently have become aware of a hazard due to the presence of radioactive ²¹⁰Pb in their boilers. In an investigation conducted by KEMA in The Netherlands it was discovered that ²¹⁰Pb isotope accumulates within fire‐side deposit layers that form on membrane waterwall tubes. Because the measured levels of total radioactivity exceeded the governmental regulation limit of 100 Bq/g, refurbishment activities in the boiler are subject to governmental authorization and must be conducted under the supervision of authorised radiation protection officers. The ²¹⁰Pb material originates from decay of ²³⁸U, which is present in small amounts in coal. During combustion of the coal, heavy metals such as Pb evaporate and are present in the flue gas in the form of Pb, PbCl, PbCl₂, PbS, PbS₂ or PbSO₄, dependent on the gas environment and temperature. These volatile products subsequently will condense at lower temperatures on the waterwall tubes in the boiler.

The purpose of this paper is to evaluate the possible use of oil shale as a soil stabilizing agent for expansive soils.

An experimental work has been fulfilled to investigate the influence of oil shale ash (OSA) on the geotechnical behavior of the expansive soil of Irbid, Jordan. Three swelling-shrinkage soils were considered in this study along with various percentages of OSA varying at 2, 4, 6, 8, 10 and 12 per cent by dry weight of the soil. A series of laboratory tests were conducted on the soil samples before and after mixing it with OSA. These tests were soil classification, Atterberg limits, compaction test, falling head permeability test, unconfined compression test, free swelling, swelling pressure and California bearing ratio (CBR) test.

Laboratory tests results indicated that OSA is effective in improving the texture and strength of the treated soil by reducing plasticity index, swelling potential and swelling pressure and moderately enhancing soil strength properties including the unconfined compressive strength (q_u), maximum dry unit weight (γ_d-max.) and CBR test.

OSA showed potential as a low-cost soil stabilizing agent for swell-shrink soils.