[en] Maintenance involves maintaining and securing the equipment and systems in, or restoring them to, a state in which they can perform the required functions. The challenge for maintenance planning is to identify appropriate objects and tasks for preventive maintenance and ensure that there are adequate resources for the repair actions. In this paper we will present a maintenance planning approach, called value-driven maintenance planning (VDMP), to emphasise the fact that the objectives of the plant are the reference points for specifying functional requirements for the equipment locations and equipment. The three basic phases of the VDMP planning approach are: (i)the definition of the fundamental, strategic and maintenance (means) objectives of the production plant, (ii)the classification of equipment locations (including one or several equipment items) into maintenance classes, each associated with a functional requirement specification, and (iii)the selection of maintenance strategies and maintenance tasks (including timing) for equipment assigned to the equipment locations. Feedback of the operational experience is crucial for the application of the maintenance planning approach. As a consequence, the approach is developed to support the continuous improvement of the cost effectiveness of maintenance rather than planning of the initial maintenance programme of a new plant. Analysis techniques are presented and challenges of application are discussed. The application of the VDMP approach to a gasification plant in Finland is also presented

[en] Compaction grouting was developed in the 1950s as a remedial measure for the correction of building settlement, and used almost exclusively for that purpose for many years. Over the past 25 years, however, compaction grouting technology has evolved to treat a wide range of subsurface conditions for new and remedial construction. Compaction grouting is used foundation rehabilitation, ground improvement, railroad subgrade stabilization, seismic/liquefaction mitigation, sinkhole remediation, tunneling stabilization, void filling. It also has merit that makes possible to construct structures having narrow working spaces. But the effects of ground improvement depending on the type of soil must be studied in order to adopt in various soil(granular soil and cohesive soil). In this paper, field and laboratory tests were performed to understand effects of ground improvement for soft ground and seismic mitigation. To know the characteristics of bearing capacity in adjacent ground, plate loading test for behind the improving ground. Strength characteristics of TCS were indicated by uniaxial compression test. Ground improvement effect by TCS together strength increment effect by TCS itself was proved that TCS can be used for soil improvement method using bearing capacity increment. (paper)

[en] This paper presents the results of the three-dimensional (3D) discrete element method (DEM) simulations of undrained axisymmetric/triaxial tests on loose assemblies of polydisperse spheres with and without preshearing history using a periodic cell. Undrained tests are modelled by deforming the samples under constant volume conditions. The simulations show that the preshearing process will not induce initial structural anisotropy, and that the presheared and unpresheared samples follow the same initial stress path along a unique limiting boundary in the q–p space, as observed in the published experimental literature, which was not crossed over by any of the stress paths of the presheared samples. It is also shown that the presheared samples are denser compared with the original unpresheared one, and therefore exhibit higher resistance to (temporary) liquefaction. At the grain scale, such higher resistance is found to be attributed to the evolution of a redundancy factor, a microscopic definition of liquefaction (temporary liquefaction). The Lade instability (peak deviator stress) is found to correspond to a unique mechanical coordination number of 4.5, independent of preshearing history. It is also found that the onset of liquefaction (temporary liquefaction) in terms of the redundancy factor lags behind the onset of macroscopic strain softening in terms of the Lade instability for the presheared and unpresheared samples under undrained conditions. (paper)

[en] In order to reasonably carry out dynamic analysis and seismic design of soil and soil-structure interaction system, on the basis of dynamic triaxial tests, a permanent strain potential model for saturated silty soil during seismic liquefaction is established. And it can well fit the development rule of strain during liquefaction of silty soil. (paper)

[en] Efficient use of ohmic heating in the drying zone of the plasma shaft furnace for gasification of organic and technogenic wastes is studied. It is shown that by using ohmic heating in the drying zone, energy release takes place in the filling along the entire zone. (paper)

[en] The paper presents the results of mathematical and experimental studies of the process of gasification of municipal solid waste in a plasma electric furnace. The energy consumption for gasification of SMW with the organic and inorganic components of morphological composition was investigated during these studies. The effect of reducing the energy consumption during waste gasification, excluding the inorganic component of SMW was also investigated. The paper presents the results of computational and experimental studies of SMW gasification and reveals the effect of the inorganic part on the energy balance of an electric plasma furnace. (paper)

[en] Highlights: • Novel study to evaluate the effect of food waste liquefaction on biodegradability. • Energy efficiency of 11.1 kg SCOD/kWh was optimum for combinative liquefaction. • Cost spent to attain 20–40% liquefaction was very low compared to others. • No significant difference in biodegradability for samples with 40–60% liquefaction. • Achievement of 40% liquefaction was beneficial in terms of energy and cost. - Abstract: In the present study, a new and novel attempt was made to investigate the effect of liquefaction (20–60%) on energy efficient gaseous biofuel recovery and cost during chemo thermo disperser liquefaction of food waste (CTDL). The outcome of the study revealed that rpm (10,000), specific energy input (174 kJ/kg TS), disintegration time (5 min) and energy efficiency of about 11.1 kg SCOD/KWh were considered as optimum in terms of energy and cost. The cost incurred to achieve 20–40% liquefaction was estimated to be 0.0132–0.0168 USD and found to be comparatively very low than the cost incurred (0.0367–0.0547) to achieve 50–60% liquefaction. The biodegradability results showed that a significant increment in biodegradability was achieved (from 0.26 gCOD/gCOD to 0.8 gCOD/gCOD) when the liquefaction was increased from 30 to 40% and an insignificant increment in biodegradability (from 0.8 gCOD/gCOD to 0.84 gCOD/gCOD) was achieved when the liquefaction was increased from 40 to 60%, respectively. The impact of liquefaction on energy balance and cost at tonnage level revealed that 40% liquefaction was considered to be profitable with energy ratio and net profit of about 1.12 and 93 USD/Ton, respectively.

[en] The post liquefaction behavior of buried conduits is analyzed and sensitivity analysis is conducted to investigate the damage potential of the forces induced in the buried lifelines following seismically induced liquefaction of the surrounding soil. Various lifeline configurations and loading conditions are considered. The loading conditions considered are: buoyancy forces and permanent ground displacements parallel to the lifeline axis. Pertinent parameters for the soil-lifeline interaction following liquefaction are identified. (author)

[en] Full text: The field of cryogenics deals with the study of low temperature processes. For the analysis of these processes there are used both the methods and laws of thermodynamics of macroscopic systems and the methods and laws which are at the basis of magneto-caloric phenomena in certain substances and in certain physical conditions of mass of those substances and of the environment. The most important elements which have to be taken into consideration when talking about this field are: liquefactors or cryogenerators, energy and safety. The project C43 represents a continuation of the work done previously by several institutions in the field of cryogenics and of material behaviour at cryogenic temperatures and has as the main objective the creation of an integrated platform for the study of cryogenic processes. The studies will be performed both from the point of view of installations, cryogenic cycles and direct use of cryogenic products and for the obtaining of experimental data at interdisciplinary level. The project C43 generated a complex integrated system (institutes, laboratories, equipment and experimental bench) for testing/characterisation of a material at cryogenic temperatures. (authors)

[en] After the Haiti quake of 2010 an initiative started to better understand shaking effects in the Dominican Republic after natural earthquakes, in particular in the city of Santiago de los Caballeros, the second city in the country as far as inhabitants and economic wealth are concerned. Santiago has suffered several devastating earthquakes; in 1562 the city was rebuilt on a new site (the current location) further south from the responsible fault. It is well known that damage caused by an earthquake occurs associated to a number of factors, ground acceleration is one of them and is usually considered as the key to explain most of the damage. Ground acceleration varies from one point to another depending mainly on: distance to the source of the rupture, soil properties and topography. Regarding the distance, the further from the source the less acceleration is expected due to distance attenuation. On the other hand, different soil properties and different topographies will produce different responses to the propagating wave. Within the range of a few kilometres, the effect of distance attenuation might be far less relevant than the effect of the varying properties of soils. This paper gathers together results obtained from the seismic hazard and microzonation studies developed in the city of Santiago: i) quantification of regional seismic hazard dominated by the Septentrional fault, ii) a new geological mapping of superficial formations, and iii) mapping of zones of homogeneous seismic response and liquefaction susceptibility.