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A mathematical model is developed to represent the one-dimensional large-strain consolidation of a fully saturated clay. The fluid limit is postulated to be that water content associated with a 'stress-free' condition of the soil, and it is taken as the reference state from which strains are measured.Experimental results from a series of permeability tests suggest that the relationship between the logarithm of the coefficient of permeability and the void ratio is not a straight line for the entire range of void ratio considered.In addition, the variation of the constrained modulus as consolidation progresses is taken into account.The resulting boundary value problem involves a nonlinear partial differential equation with void ratio as the dependent variable, and the numerical solution is accomplished by a step-by-step procedure combined with a weighted residual technique which leads to a finite element discretization in the spatial variable and a finite difference discretization in the time variable. The mathematical model is applied to four cases (two involving a salt flocculated kaolinite slurry and two involving a dispersed kaolinite slurry) in the stress range within which a 'slurry' is transformed to a 'soil'. For the particular clay (Hydrite 10) investigated it was found that classical small-strain consolidation theory can adequately describe the deformation-time response for all practical purposes after the effective consolidation stress on the slurry had exceeded a value of about 8 lb/in.2 (55 kN/ma).Un modele mathematique est utilise pour rep&enter la consolidation a une dimension a grande deformation d'une argile totalement saturee. La limite de fluidit est supposee &re la teneur en eau correspondant a une condition de sol sans contrainte et elle est prise comme base de reference a partir de laquelle les deformations sont mesurees. Des resultats experimentaux obtenus a partir d'une serie d'essais de permeabilite montrant que la relation entre le logarithme du coefficient de permeabilite et l'indice des vides n'est pas une ligne droite pour l'ensemble des indices des vides consider& dans cette etude. De plus, on tient compte de la variation du module de dtformation en fonction de la consolidation.L'ktude du problbme resultant de la prise en compte des conditions aux limites aboutit a une equation partielle differentielle non lineaire avec l'indice des vides comme variable dtpendante, et la solution numerique est obtenue par approximations successives combinees a une technique de ponderation residuelle qui conduit a une discretisation d'elements finis dans la variable espace et une discretisation de differences finies dans la variable temps. Le modele mathematique est applique a quatre.cas (deux concernant un coulis de kaolinite salee floculee et deux concernant un coulis de kaolinite diluee) dans la gamme des contraintes dans laquelle un 'coulis' est transform6 en un 'sol'. Pour une argile particulitre (Hydrite lo), la recherche a montre aue la theorie classiaue de consolidation a faible dtformation est ...

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Since the economic reforms that began 20 years ago, and especially with the enterprise reforms in recent years, ownership of Chinese construction firms has evolved from traditional state and collective ownership towards a mixed economy characterised by diversified ownership forms. Based on a questionnaire survey and personal interviews with individuals from firms representing four types of ownership, it has been determined that the majority of Chinese construction firms have already embraced commercial objectives and behaviour patterns similar to those of typical firms in developed market economies. Nevertheless, despite the important progress that the reforms have made, this study indicated that various construction firms during this transition are suffering serious difficulties caused by the former planned system and underdeveloped market mechanisms. Unfair practices were found to be quite serious in the construction market. Major problems stem from clients' abnormal behaviour in forcing the price down, asking contractors to finance a project wholly or partially during its construction, and delays in payment; these actions have caused severe financial difficulties to Chinese firms and seriously disrupted the normal order of market stability.China, Chinese construction firms, reform, firm objective, firm behaviour, ownership form,