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the bottom plates and at the lower edge of the cylindrical shell. There are known cases of steel tank bottom failures, in which excessive or non-uniform deformation of the sand foundation inside the ring foundation [ 1 ], [ 2 ] occurred. Advanced analyses of the influence of the soil settlement of tank bottoms on the state of their and shells’ stresses are included in the doctoral thesis [ 3 ]. The paper presents the analyses of the support of chosen steel tanks on ring foundations, in which the bottom plates may crack due to large and non-uniform settlement

Abstract

The paper deals with the probabilistic analysis of the settlement of a non-cohesive soil layer subjected to cyclic loading. Originally, the settlement assessment is based on a deterministic compaction model, which requires integration of a set of differential equations. However, with the use of the Bessel functions, the settlement of a soil stratum can be calculated by a simplified algorithm. The compaction model parameters were determined for soil samples taken from subsoil near the Izmit Bay, Turkey. The computations were performed for various sets of random variables. The point estimate method was applied, and the results were verified by the Monte Carlo method. The outcome leads to a conclusion that can be useful in the prediction of soil settlement under seismic loading.

Abstract

In an artificial island construction project based on the large-scale marine reclamation land, the soil settlement is a key to affect the late safe operation of the whole field. To analyze the factors of the soil settlement in a marine reclamation project, the SEM method in the soil micro-structural analysis method is used to test and study six soil samples such as the representative silt, mucky silty clay, silty clay and clay in the area. The structural characteristics that affect the soil settlement are obtained by observing the SEM charts at different depths. By combining numerical calculation method of Terzaghi’s one-dimensional and Biot’s two-dimensional consolidation theory, the one-dimensional and two-dimensional creep models are established and the numerical calculation results of two consolidation theories are compared in order to predict the maximum settlement of the soils 100 years after completion. The analysis results indicate that the micro-structural characteristics are the essential factor to affect the settlement in this area. Based on numerical analysis of one-dimensional and two-dimensional settlement, the settlement law and trend obtained by two numerical analysis method is similar. The analysis of this paper can provide reference and guidance to the project related to the marine reclamation land.

Abstract

The paper deals with the comparison of Biot’s model for saturated, porous soils with other simplified models used in dynamic analysis. The purpose of this paper is to determine some limits of validity of the various models. In order to do this a full set of governing, dynamic equations of Biot model and a series of simplifying models such as u-p simplification and quasi-static consolidation models are considered. These formulations are applied to a simple soil layer under periodic surface loading. A displacement of skeleton and a displacement of fluid are shown and compared with each model for various formulations.

Abstract

Forging hammers are machines whose operation causes negative effects both at the place of their foundation (the soil settlement) and in their surroundings (e.g., vibrations propagating to the other devices, noise, etc.). Knowledge of the parameters characterizing the time history of the force that arises as a result of impact of a ram on a shaped material is of fundamental importance for the correct analysis of both the structure of the hammer and its impact on the surroundings. In the paper, the effect of the shape and duration of a pulse load on the dynamic response of a hammer-foundation forging system was assessed. An analytical method of description of the forces that arise as a result of impact of the ram on the forged material, using different forms of pulses was presented. The forces defined in this way as loads in a mathematical model of three degrees of freedom forging system were used. The equations of motion derived from d’Alembert’s principle were solved numerically in the Matlab program. The analyses for eight forms of the pulse loads with the same pulse sizes but different durations were performed. The results in the graphs were presented. It was found, among other things, that a greater impact on the maximum displacement, velocity and acceleration of each component of the hammer-foundation system as well as on the maximum forces transmitted to the soil has the duration of a pulse than its shape.

. – Hellmich Ch. – Eberhardsteiner, J.: Loading of Soil-covered Oil and Gas Pipelines due to Adverse Soil Settlements – Protection Against Thermal Dilatation-induced Wear, Involving Geosynthetics, Computers and Geotechnics, Vol. 33, No. 8, Elsevier, 2006 Newson, T. A. – Deljoui, P.: Finite Element Modelling of Upheaval Buckling of Buried Offshore Pipelines in Clayey Soils, ACSE 2007

Geomechanics and Hydrogeology, Princeton University Press, 2000. [18] WRANA B., Computational Models of Soil Dynamics , Cracow University of Technology (in Polish), 2012. [19] WRANA B., PIETRZAK N., Influence of Inertia Forces on Soil Settlement under Harmonic Loading , Studia Geotechnica et Mechanica, No. 1, 2013, 245-258. [20] ZAMMAN M., GIODA G., BOOKER J., Modelling in Geomechanics , John Wiley & Sons, 2000. [21] ZIENKIEWICZ O.C., CHAN A.H.C., PASTOR M., SCHREFLER B.A., SHIOMI T., Computational Geomechanics with Special Reference to Earthquake Engineering , John

REFERENCES 1. M. Bukowski, P. Łysiak, R. Oleszek, W. Trochymiak, “Reasons of Emergence of Differences in Soil Settlement between the Viaduct and the Embankment on Siekierkowska Route”, Archives of Institute of Civil Engineering. Ed. Poznan University of Technology, 24/2017, 39-58, ISSN 1897-4007, DOI: 10.21008/j.1897-4007.2017.24.03 (in Polish). 2. R. Ciesielski, M. Maciąg, „Road vibrations and their influence on buildings”, Copyright by Wydawnictwo Komunikacji i Łączności, Warszawa, 1990. („Drgania drogowe i ich wpływ na budynki”) (in Polish). 3. R. W. Day

podłoża gruntowego w świetle posadowienia turbin wiatrowych (cz. I) , Geoinżynieria drogi mosty tunele, 45(4), pp. 42–48. 22. Z hao J., B ao L., W ang G., (2017), Numerical analysis of soil settlement prediction and its application in large-scale marine reclamation artificial island project , Polish Maritime Research, Special Issue S3, 24(95), pp. 4–11. 23. Z hou M., Y uan W., Z hang Y., (2015), Seismic material properties of reinforced concrete and steel casing composite concrete in elevated pile-group foundation , Polish Maritime Research, Special Issue S1, 22

rates. Keywords: segment of pile foundation, plate not joining a pile, additional skin friction, successive loading. 1. INTRODUCTION Piled raft foundations under the entire structure or the most loaded superstructures are typically designed for high rise buildings. Construction and maintenance of standard pile foundations has two extreme aspects: first, grillage is not used in the maintenance period due to soft soil settlement and the presence of a hollow space underneath it; secondly, the grillage provides additional bearing capacity reserves, which are not