A complete case of a deep excavation was explored. According to the practical working conditions, a 3D non-linear finite element procedure is used to simulate a deep excavation supported by the composite soil nailed w...A complete case of a deep excavation was explored. According to the practical working conditions, a 3D non-linear finite element procedure is used to simulate a deep excavation supported by the composite soil nailed wall with bored piles in soft soil. The modified cam clay model is employed as the constitutive relationship of the soil in the numerical simulation. Results from the numerical analysis are fitted well with the field data, which indicate that the research approach used is reliable. Based on the field data and numerical results of the deep excavation supported by four different patterns of the composite soil nailed wall, the significant corner effect is founded in the 3D deep excavation. If bored piles or soil anchors are considered in the composite soil nailed wall, they are beneficial to decreasing deformations and internal forces of bored piles, cement mixing piles, soil anchors, soil nailings and soil around the deep excavation. Besides, the effects due to bored piles are more significant than those deduced from soil anchors. All mentioned above prove that the composite soil nailed wall with bored piles is feasible in the deep excavation.展开更多
Performance-Based Design （PBD） is a more rational approach, particularly in seismic environments. In this approach it is relevant the performance required to structures and to geotechnical works, as well as the geot...Performance-Based Design （PBD） is a more rational approach, particularly in seismic environments. In this approach it is relevant the performance required to structures and to geotechnical works, as well as the geotechnical constitutive models used to predict the performance. The parameters of the constitutive models are related in turn to soil properties. So soil properties are a key point for Performance-Based Design. Questions arising are： （i） which are the more relevant soil properties to solve a specific PBD geotechnical problem？ （ii） which are the more relevant model parameters and how they can be evaluated and/or correlated to soil properties？ （iii） which is the role of the soil parameters uncertainty in Performance-Based Design？ An answer to these questions is given in this paper, outlining the potential offered by the new advanced in-situ and laboratory tests and discussing the performance required by some geotechnical works.展开更多
基金Foundation item： Project（2009-K3-2） supported by the Ministry of Housing and Urban-Rural Development of China
文摘A complete case of a deep excavation was explored. According to the practical working conditions, a 3D non-linear finite element procedure is used to simulate a deep excavation supported by the composite soil nailed wall with bored piles in soft soil. The modified cam clay model is employed as the constitutive relationship of the soil in the numerical simulation. Results from the numerical analysis are fitted well with the field data, which indicate that the research approach used is reliable. Based on the field data and numerical results of the deep excavation supported by four different patterns of the composite soil nailed wall, the significant corner effect is founded in the 3D deep excavation. If bored piles or soil anchors are considered in the composite soil nailed wall, they are beneficial to decreasing deformations and internal forces of bored piles, cement mixing piles, soil anchors, soil nailings and soil around the deep excavation. Besides, the effects due to bored piles are more significant than those deduced from soil anchors. All mentioned above prove that the composite soil nailed wall with bored piles is feasible in the deep excavation.
文摘Performance-Based Design （PBD） is a more rational approach, particularly in seismic environments. In this approach it is relevant the performance required to structures and to geotechnical works, as well as the geotechnical constitutive models used to predict the performance. The parameters of the constitutive models are related in turn to soil properties. So soil properties are a key point for Performance-Based Design. Questions arising are： （i） which are the more relevant soil properties to solve a specific PBD geotechnical problem？ （ii） which are the more relevant model parameters and how they can be evaluated and/or correlated to soil properties？ （iii） which is the role of the soil parameters uncertainty in Performance-Based Design？ An answer to these questions is given in this paper, outlining the potential offered by the new advanced in-situ and laboratory tests and discussing the performance required by some geotechnical works.
