Dissertação

{pt_PT=Cyclic thermal loading on single piles} {} EVALUATED

{pt=The paper reviews unconventional way of ground heat extraction, based on the use of subterranean structural elements. The method has been utilized since relatively recently, comparing to the other renewable heat generation methods and therefore, it still needs to be propagated. The thesis seeks to review significant earlier findings of the dependencies between a single energy pile and the adjacent soil for a bonded mechanical and thermal loads. The first sections of the text aims at explaining the mode of operation of the system, completed with a detailed description of its components. Numerous factors influencing the efficiency of the system were investigated, including soil and groundwater conditions as well as the selection of structural materials. Additionally, the potential of energy pile system utilization in Portugal has also been presented, which indicates a very good possibilities of its implementation. Subsequently, numerical verification of a chosen case study was carried out by means of finite element method software Plaxis, resulting with satisfactory results of the pile response parameters. After the analysis of steady state thermal changes, a parametric study of a single pile assigned to thermal cycles was conducted, paying a special attention to the influence of the degree of the pile head fixation on the energy pile response especially in terms of its generated forces. The results were in accordance with the expected, described in preceding chapters thermo-mechanical rules. , en=The paper reviews unconventional way of ground heat extraction, based on the use of subterranean structural elements. The method has been utilized since relatively recently, comparing to the other renewable heat generation methods and therefore, it still needs to be propagated. The thesis seeks to review significant earlier findings of the dependencies between a single energy pile and the adjacent soil for a bonded mechanical and thermal loads. The first sections of the text aims at explaining the mode of operation of the system, completed with a detailed description of its components. Numerous factors influencing the efficiency of the system were investigated, including soil and groundwater conditions as well as the selection of structural materials. Additionally, the potential of energy pile system utilization in Portugal has also been presented, which indicates a very good possibilities of its implementation. Subsequently, numerical verification of a chosen case study was carried out by means of finite element method software Plaxis, resulting with satisfactory results of the pile response parameters. After the analysis of steady state thermal changes, a parametric study of a single pile assigned to thermal cycles was conducted, paying a special attention to the influence of the degree of the pile head fixation on the energy pile response especially in terms of its generated forces. The results were in accordance with the expected, described in preceding chapters thermo-mechanical rules. }
{pt=Energy pile, axisymmetric model, thermo-mechanical loading, soil-pile interaction, pile head restraint, en=Energy pile, axisymmetric model, thermo-mechanical loading, soil-pile interaction, pile head restraint}

Novembro 26, 2019, 11:0

Publicação

Obra sujeita a Direitos de Autor

Orientação

ORIENTADOR

Jaime Alberto dos Santos

Departamento de Engenharia Civil, Arquitectura e Georrecursos (DECivil)

Professor Associado