摘要:

AbstractFinite element solutions of consolidation problems often exhibit oscillating pore pressures, which tend to increase when the time steps are reduced. This phenomenon is investigated and a lower limit for the time steps is derived, in terms of the mesh size and the coefficient of consolidation near the draining boundary.

ISSN:0363-9061    

DOI:10.1002/nag.1610050103

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractDirect and indirect formulations of the boundary element methods are described for two‐dimensional problems of transient ground water low. A numerical algorithm for obtaining solutions to complete any two‐dimensional problem is outlined. The algorithm has been applied successfully to several problems which demonstrate its usefulness in pract

ISSN:0363-9061    

DOI:10.1002/nag.1610050104

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractA numerical approach is presented for the ‘identification’ (or back calculation) of the earth pressure acting on embedded or retaining structures. The procedure is applicable to structures of any shape and requires a set ofin situmeasurements that may include displacements of points on the structure, values of concentrated forces, values of distributed loads at some locations, etc. Possible limiting values of the unknown loads, non‐linear structural behaviour, varying accuracies of the input data are accounted for in the problem formulation. Depending upon the type of problem, the solution is reached by means of the unconstrained or constrained minimization of a suitably defined error function. As an example, the proposed approach is applied to the identification of the earth pressure acting on some typical geotechnical engineering struc

ISSN:0363-9061    

DOI:10.1002/nag.1610050105

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThe trap‐door problem with dry sand is treated in a statical analysis based upon model test kinematics. Integration of the equilibrium conditions along horizontal slices and introducing the mean value for the vertical stresses yields a differential equation for the trap‐door force. Concerning the constitutive response of sand a statical model of a moving shear band is proposed as an internal boundary. Solutions for the trap‐door force for the active and passive modes and for the ultimate and residual states are disc

ISSN:0363-9061    

DOI:10.1002/nag.1610050106

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractMeasurements are conducted with small samples in the laboratory and thus for all practical purposes the medium is macroscopically homogeneous. On the other hand, the uncertainties and the irregular changesin situare macroscopic inhomogeneities. This work is an attempt to account for these stochastic changes in the elastic properties and density in a rational manner. The method used is that of Karal and Keller which is based on the use of the Green's function and neglect of third‐order correlations. The resulting integral equations are solved by Laplace transform. The analysis indicates that the energy decay in the mean motion through random mode coupling introduces damping into even a purley'elastic medium and enhances the damping in a significant manner in a hysteretic viscoelastic medium. This consideration is important in relating the damping and dispersion characteristics of wavein situto those measured in the laboratory. The formulation is extended to multilayer systems through transfer matrices and to arbitrary inputs by Fourier transform. Sample calculations are presented for single and multilayer systems to obtain response spectra and for the response to Gaussian and actual earthquake input motion

ISSN:0363-9061    

DOI:10.1002/nag.1610050107

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

ISSN:0363-9061    

DOI:10.1002/nag.1610050102

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY