Search results for "Civil Engineering"
showing 10 items of 1216 documents
Embedding “substrate” in environmental assessment of green roofs life cycle: evidences from an application to the whole chain in a Mediterranean site
2012
Abstract A classical LCA methodology is here applied to green roofs including in this analysis also the whole life cycle of the substrate, that represented a lack of previous LCA studies on green roofs. This inclusion will allow a complete and proper application of the LCA methodology to achieve an environmental accounting of the “green roof” performance. We have here chosen to approach the problem by analysing a specific substrate, that is used within an actual extensive green roof. Afterwards, we have applied the LCA methodology to the whole actual extensive green roof whose substrate under analysis is part of. In this manner, we achieved an environmental accounting of the “green roof” pe…
Annual heating energy requirements of office buildings in a European climate
2016
Abstract The concept of implementing energy savings to reduce greenhouse gas emissions has become a key element of energy policies of any industrialized country. In the civil sector and specifically, energy savings for office buildings, there are still opportunities for further enhancements related to correctly determining the air conditioning thermal requirements. However, there is a lack of simple correlations that allow a preliminary assessment for a single building or correlations that can be quickly applied at the district level. This paper proposes several simple correlations that determine the heating loads of a typical office building by only knowing the Degree-Days of a specific Eu…
Review of the energy and economic parameters involved in the effectiveness of grid-connected PV systems installed in multi-storey buildings
2014
Abstract The assessment of PV energy in an urban context is extremely complex because many factors have to be considered. Moreover, when the purpose is calculating the realistic amount of the electricity demand of a city that can be covered by the photovoltaic generation, it is necessary to estimate the number of photovoltaic systems whose installation is economically advantageous. Such a topic requires an economic analysis, which is affected by the number of energy and economic parameters involved and the values assigned to them to perform calculations. Some parameters are perfectly known and unvarying, like the paid incentives. Adversely, some parameters, like the efficiency degradation o…
Small Wind Technology Diffusion in Suburban Areas of Sicily
2015
Among renewable energy resources, wind energy became more attractive in the last decade. Wind farm installations dramatically increased in areas where climatic conditions, topography, and environment have allowed their development. The installation of wind turbines, usually carried out in remote areas, recently began to cover areas identified by a complex terrain such as urban and suburban zones. Although these new plant choices are characterized by lower productivity, there is increasing interest in wind energy production in both urban and suburban areas. In this work the authors have carried out an energy analysis developed from a sample of small wind turbines available on the market. Thi…
Robust Control Allocation for Spacecraft Attitude Stabilization under Actuator Faults and Uncertainty
2014
A robust control allocation scheme is developed for rigid spacecraft attitude stabilization in the presence of actuator partial loss fault, actuator failure, and actuator misalignment. First, a neural network fault detection scheme is proposed, Second, an adaptive attitude tracking strategy is employed which can realize fault tolerance control under the actuator partial loss and actuator failure withinλmin=0.5. The attitude tracking and faults detection are always here during the procedure. Once the fault occurred which could not guaranteed the attitude stable for 30 s, the robust control allocation strategy is generated automatically. The robust control allocation compensates the control …
Reliability Approach to the Design, Construction and Use of Natural Draught Cooling Towers
1989
Structures or structural elements should be designed and constructed such they are suited to their intended use. But principles for the design, construction, use and maintenace are changing evolutionary. It is due to fundamental research and the progress in technology.
Interaction between Longitudinal Shear and Transverse Bending in Prestressed Concrete Box Girders
2017
In box girder bridges, the quantity and distribution of reinforcement to be put in concrete elements of sections can be evaluated only by considering the deformation of the cross section in addition to the longitudinal analysis of the static scheme, establishing the entire state of stress of box sections. This leads to a need to evaluate the interaction between internal forces obtained by the global analysis and the ones obtained by the local analysis of the cross sections. The frame effect implies the elastic deformation of slabs and webs, whereas eccentrically applied loads lead to cross-section distortion with the loss of the box shape. Hence, the reinforcement is strongly influenced by …
Reconstruction of the Rib Vaults of the Hypostyle Hall in the Maniace Castle of Siracusa After the 1693 Earthquake
2016
ABSTRACTBuilt in the first half of the 13th century on behalf of the Emperor Frederick II, the Maniace Castle of Siracusa focuses its enigma in the hypostyle hall (which was composed of 25 quadripartite rib vaults) and the design criteria adopted for its implementation. Recent research and a careful rereading of the documentary “restoration project” after the earthquake of 1693 have offered new tools to understand the construction techniques and building procedures for the entire organism. It has been possible to demonstrate that the different material (white limestone and volcanic stone) used for the vaults is, in fact, a product of reconstruction. The constructive node, which historiograp…
Stabilization and Solidification Technology Implementation in Latvia: First Studies
2012
Soil and groundwater are environmental compartments that are primarily affected by industrial development with increasing amount of industrial wastes and inadequate dumping of them. A special attention should be paid to heavy metal contamination at least 56 contaminated territories of National priority are known as contaminated with heavy metals in different amount and concentration in Latvia. The stabilization / solidification technology refers to binding of waste contaminants to a more chemically stable form and thus diminishing leaching of contamination. In order to choose the remediation method the pre-investigation in industrial case study area was done in stages: data analysis of prev…
Hydraulic Dynamic Calculation and Simulation
2021
Hydraulic dynamics is emerging as a basic concept with applications and important implications for many industrial, civil, and environmental engineering problems [...]