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There are two important conditions for the wide application of constitutive models for soil in contemporary engineering practice: a) the model should predict sufficiently well the soil behaviour at different stress paths; b) the material constants of the model can be determined from standard laboratory tests. Taking into account both conditions, a HASP model has been formulated to describe the mechanical behaviour of the overconsolidated clays, using the critical state theory and the boundary surface concept. The HASP model in a simple way overcomes many deficiencies of the Modified Cam Clay model, without introducing any additional material parameters. The formulation of the hardening rule in the function of the state parameter and overconsolidation ratio, allows the description of numerous elements of the mechanical behaviour of the overconsolidated clays. The HASP model has been implemented in software Abaqus using the Governing Parameter Method for the numerical integration of constitutive relations. The paper presents validation of the HASP model in comparison with the published results of triaxial tests as well as the possibilities of the model to adequately predict the behaviour of the overconsolidated clays through the analysis of the boundary value problem using the finite element method. The problem of the clay settlements due to phased construction of the embankment on the saturated clay surface was analyzed, assuming different overconsolidation ratios. Za široku primenu konstitutivnih modela za tlo u savremenoj inženjerskoj praksi postoje dva bitna uslova: a) model treba dovoljno dobro da predviča ponašanje tla pri različitim putanjama napona; b) materijalne konstante modela mogu da se odrede iz standardnih opita. Uvažavajući oba uslova, formulisan je HASP model za opisivanje mehaničkog ponašanja prekonsolidovanih glina, koristeći teoriju kritičnog stanja i koncept granične površi. HASP model, na jednostavan način, prevazilazi mnoge nedostatke Modifikovanog Cam Clay modela, bez uvočenja dodatnih materijalnih parametara. Formulacijom zakona ojačanja u funkciji parametra stanja i stepena prekonsolidacije, omogućeno je opisivanje brojnih elemenata mehaničkog ponašanja prekonsolidovanih glina. HASP model je implementiran u program Abaqus koristeći Metodu vodećeg parametra za numeričku integraciju konstitutivnih relacija. U radu je prikazana validacija HASP modela - porečenjem s publikovanim rezultatima triaksijalnih opita, kao i mogućnosti modela da adekvatno predvidi ponašanje prekonsolidovanih glina putem analize graničnog (konturnog) problema metodom konačnih elemenata. Razmatran je problem konsolidacionog sleganja tla usled fazne izgradnje nasipa na površini zasićene prekonsolidovane gline, za različite stepene prekonsolidacije.

Pouzdanost analiza geotehničkih problema numeričkih metoda kao što su metoda konačnih elemenata... Accuracy and reliability of geotechical analysis by numerical methods such ....

Pouzdanost analiza geotehničkih problema numeričkih metoda kao što su metoda konačnih elemenata... Accuracy and reliability of geotechical analysis by numerical methods such ....