Showing papers on "Foundation (engineering) published in 2018"
TL;DR: In this article, a review of foundations for offshore wind energy convertors considering the significant growth of offshore wind power since the early 2000s is presented, where the characteristics of various foundation types (i.e., gravity, pile, suction caisson, and float type) and current status of field application are discussed.
Abstract: This paper reviews foundations for offshore wind energy convertors considering the significant growth of offshore wind energy since the early 2000s. The characteristics of various foundation types (i.e., gravity, pile, suction caisson, and float type) and the current status of field application are discussed. Moreover, the mechanical characteristics of soil are described in the sense that these characteristics including modulus, strength, damping, and modulus degradation of soil play critical roles for the design of offshore foundations. By using these mechanical properties of soil, theoretical studies to consider structure-soil interaction are classified (into equivalent spring models, distributed spring models, and continuous element models) and explained. Field and laboratory experiments on the response of structure embedded in soil to static and dynamic loads are discussed. Based on the review of previous studies, directions for future research and study on offshore wind turbine are suggested.
227 citations
TL;DR: In this article, a comprehensive review of variable types of offshore wind substructures associate with their corresponding example projects is presented, complemented with a special attention to a novel foundation, namely suction bucket foundation.
189 citations
TL;DR: In this paper, the authors investigated the dynamic responses of an offshore wind turbine supported on a monopile foundation in clay subjected to wind, wave and earthquake actions, and the results indicated that it is necessary to consider the combination of wind and wave actions in the design of offshore wind turbines.
136 citations
TL;DR: In this paper, an innovative hybrid monopile foundation for offshore wind turbine (OWT) is proposed, which is an optimization of the original monopile foundations with broader applications, by considering the effects of wind, waves, and ice.
106 citations
Book•
24 Apr 2018
97 citations
Abstract: This paper proposes a novel multidimensional composite periodic foundation for seismic isolation. The composite periodic foundation achieves multidimensional attenuation by innovative arrangement of periodic structures and taking advantage of the directional attenuation zone of periodic structures. Directional attenuation zones of periodic structures are derived for the in‐plane wave, and the impact of geometrical parameters of the periodic structure on the characteristics of the directional attenuation zones is studied. The effectiveness of the proposed composite periodic foundation is demonstrated through application in seismic isolation for nuclear power plant structures. Harmonic analysis and time history analysis results show that the proposed composite periodic foundation with low‐frequency directional attenuation zones can effectively reduce vibrations of the upper structure in both horizontal and vertical directions.
93 citations
TL;DR: In this article, a series of centrifuge tests was performed to investigate the lateral bearing capacities of the hybrid monopile-friction wheel foundation under monotonic loads, and two analytical methods were proposed and compared with the centrifuge test results.
74 citations
TL;DR: In this article, the authors present a case study of investigating damages in existing building adjacent to foundation pit in construction, in which the settlement influence of adjacent building induced by constructing foundation pit is demonstrated by means of field observation, numerical analysis and experimental investigation.
70 citations
TL;DR: Suction caissons are a promising foundation concept for supporting offshore wind turbines as discussed by the authors, but they are not suitable for applications in the oil and gas industry, where most practical experience exists.
Abstract: Suction caissons are a promising foundation concept for supporting offshore wind turbines. Compared to applications in the oil and gas industry, where most practical experience exists, significant ...
63 citations
TL;DR: In this article, the bearing capacity of composite foundation consisting of T-shaped columns and soft clay is investigated, and the experimental results indicated that the column failure might occur at small-diameter column just below the column cap, which then led to the soil failure nearby.
Abstract: The T-shaped column is a soil-cement column with two diameters, which is installed by foldable deep mixing blades for soft clay treatment. As a variable-diameter column, its design method is not well established, and this study focuses on the bearing capacity of composite foundation consisting of T-shaped columns and soft clay. A laboratory model test was employed to study the bearing capacity, stress distribution, and failure mode of the composite foundation. Twelve full-scale loading tests were performed in the field to study the geometrical parameters of composite foundation affecting on its bearing capacity. The experimental results indicated that the bearing capacity of composite foundation increased with increasing of the cap length and column diameter, and decreasing of the column spacing. The experimental results also revealed that the column failure might occur at the small-diameter column just below the column cap, which then led to the soil failure nearby. By including this additional failure mode, the design method for conventional column was adapted to estimate the bearing capacity of composite foundation consisting of T-shaped column and soft clay, and the method was validated by the experimental data.
62 citations
TL;DR: Swelling, shrinking, and subsequent low strength of expansive soil poses significant damage to structures if it is considered as foundation or fill material as discussed by the authors. But the use of cement has become...
Abstract: Swelling, shrinking, and subsequent low strength of expansive soil poses significant damage to structures if it is considered as foundation or fill material. Recently, the use of cement has become ...
TL;DR: In this paper, a new macro-element model for monopile-based OWTs is presented, where the response of a pile and the surrounding soil is condensed to a force-displacement relation at seabed.
TL;DR: In this paper, the authors made use of GSRA grant GSRA2-1-0611-14034 from Qatar National Research Fund (a member of Qatar Foundation) to support their work.
Abstract: This publication was made possible by GSRA grant GSRA2-1-0611-14034 from Qatar National Research Fund (a member of Qatar Foundation). The finding achieved herein are solely the responsibility of author.
5 Sep 2018
TL;DR: Miller et al. as discussed by the authors provided National Science Foundation CAREER award (NEEAR-1054638) to Miller for her work in the field of computer vision and artificial intelligence.
Abstract: Funding for this work was provided through National Science Foundation CAREER award
EAR-1054638 to Miller.
TL;DR: In this article, a comprehensive set of formulas are derived for the computation of the seismic bearing capacity of strip footings resting on cohesive-frictional and purely cohesive soils, in terms of reduction coefficients for the Terzaghi's equation of the vertical bearing capacity and ultimate failure envelopes in the space of normalised loading variables.
TL;DR: In this article, two types of friction wheels, namely the solid wheel and gravel wheel, are integrated to a monopile respectively to perform as hybrid foundations, and the hybrid foundations are examined under lateral loading via centrifuge tests and three-dimensional finite-element (FE) analysis.
TL;DR: In this paper, a macro-element model for bucket foundations is proposed to capture the characteristic behavior of a shallow foundation subjected to irregular cyclic loading, which can be used as monopod foundations and in multi-leg configurations.
TL;DR: In this article, the authors investigated the behavior of a large-scale foundation pit supported by bored piles and inclined steel struts, in which the movement of the foundation pit and the displacement of the retaining structure are reported.
TL;DR: Offshore foundation systems are constantly evolving to meet the needs of developments in the energy sector as mentioned in this paper, and these developments may be induced by the requirements of moving into ever deeper waters.
Abstract: Offshore foundation systems are constantly evolving to meet the needs of developments in the energy sector. These developments may be induced by the requirements of moving into ever deeper ...
16 Oct 2018
TL;DR: In this article, the carrying capacity of Strous Meyerhoff and Begemann on sondir results was calculated using the SIS data set and the bearing capacity of the soil.
Abstract: The foundation is a part of the building construction which is responsible for accepting and eradicating all the load from the building either live load or dead load from a land market building which is strong enough to support it . To determine the soil bearing capacity soil investigation needs to be done so that the building that are above the ground is not decreased (settlelment) is large enough, then the foundation must reach solid ground layer and the bearing capacity of the soil (bearing capacity) are permitted. Strous foundation and bored pile used if the ground conditions in the bottom of the building does not have sufficient load bearing capacity to carry the load or if the hard soil that has a strong carrying capacity is located very deep from the ground surface. The purpose of this study is to calculate the carrying capacity of Strous Meyerhoff and Begemann on sondir results.
TL;DR: Soil is the foundation of ecosystem functioning in urban green spaces and provides key ecosystem as discussed by the authors, however, it is not suitable for urban areas with limited water supply and limited watershed.
Abstract: Soil is the foundation of ecosystem functioning in urban green spaces and provides key ecosystem.
TL;DR: In this article, a parametric study has been conducted by a three-dimensional finite-element method considering the full interaction between the components of piled raft foundation, and the results of numerical analyses show that the bearing capacity of a piled raft obviously increases with increasing pile length, pile spacing and raft thickness, especially in stiff clay.
Abstract: Piled raft foundations are the composite construction of a spread foundation and a few number of piles that are usually used in soft soils to compensate the weakness of a raft in satisfying the design requirements. Due to the complex behaviour of piled raft, it is necessary to take into account a number of factors such as pile geometry and arrangement, raft thicknesses, soil properties and loading condition in the design. In this study, a parametric study has been conducted by a three-dimensional finite-element method considering the full interaction between the components of piled raft foundation. The underlying soil consists of Babol clay in drained condition with various stiffness and plasticity, determined from the results of a geotechnical investigation. The results of numerical analyses show that the bearing capacity of piled raft obviously increases with increasing pile length, pile spacing and raft thickness, especially in stiff clay. The effect of load type is more significant for the differentia...
TL;DR: In this article, an outcome of research project 16•04132S, supported by the Czech Science Foundation, and of research projects IPT•370000•2010•029, supporting by the Spanish Ministry of Economy and Competitiveness is presented.
Abstract: This study is an outcome of research project 16‐04132S, supported by the Czech Science Foundation, and of research project IPT‐370000‐2010‐029, supported by the Spanish Ministry of Economy and Competitiveness.
Abstract: Over the past few decades, soil densification has been widely employed to reduce the liquefaction hazard or consequences on structures. The decision to mitigate and the design of densification specifications are typically based on procedures that assume free‐field conditions or experience. As a result, the influence of ground densification on the performance of structures and the key mechanisms of soil‐structure interaction remains poorly understood. This paper presents results of four centrifuge tests to evaluate the performance of 3‐ and 9‐story, potentially inelastic structures on liquefiable ground with and without densification. Densification was shown to generally reduce the net excess pore pressures and foundation permanent settlements (although not necessarily to acceptable levels), while amplifying the accelerations on the foundation. The influence of these demands on the performance of the foundation and superstructure depended on the structure's strength and dynamic properties, as well as ground motion characteristics. In addition, densification tended to amplify the moment demand at the beam and column connections, which increased permanent flexural deformations and P‐Δ effects (particularly on the heavier and weaker structure) that could have an adverse effect on foundation rotation. The experimental results presented aim to provide insight into the potential tradeoffs of ground densification, which may reduce foundation permanent settlement, but amplify shaking intensity that can result in larger foundation rotation, flexural drifts, and damage to the superstructure, if not considered in design. These considerations are important for developing performance‐based strategies to design mitigation techniques that improve performance of the soil‐foundation‐structure system in a holistic manner.
TL;DR: In this paper, the authors investigated the linear-elastic and nonlinear stiffnesses of a suction caisson used as monopod foundation for an Offshore Wind-Turbine (OWT).