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A simplified method for evaluating a pile-supported embankment reinforced with geosynthetic (PGRS embankment) is proposed in this paper. The method takes into account not only the arching effect, the membrane effect of the deflected geosynthetic, and the subsoil reaction, but also the pile head settlement, which makes the method applicable for floating piles, as well as piles seated on a firm soil layer. The settlement of the subsoil surface is considered to consist of two parts: (a) the settlement of the subsoil surface equals that of the pile cap with no deformation in geosynthetic yet (b) the subsoil surface subsides along with the geosynthetic deforming, and the deflected geosynthetic being considered as catenary shaped. The formula for the maximum differential settlement between the subsoil surface and the piles is worked out by analyzing the force equilibrium of the geosynthetic and the stress-strain relationship of the geosynthetic at the edge of the pile cap. The comparison of the calculated results with the observed data and the six current analytical methods has been implemented to verify the proposed method. The influence of the tensile stiffness of the geosynthetic, compression modulus of soft soil, soft soil thickness, embankment height, internal friction angle of the embankment fill and the pile spacing on the subsoil reaction, the stress concentration ratio (SCR) and the tension of the geosynthetic are investigated using the proposed method. The influence significance of these factors has been investigated using the evaluation theory of binary variance analysis for the non-repeatability tests, which helps optimize the design of the PGRS embankment. V tem članku je predlagana poenostavljena metoda za ovrednotenje nasipa, podprtega s piloti in ojačenim z geosintetikom (PGRS nasip). Metoda upošteva poleg ločnega učinka, membranskega učinka odklonjenega geosintetika in reakcije tal, tudi posedek glave pilota. Zaradi slednjega se metoda lahko uporablja tako za viseče pilote kot tudi za pilote, ki stojijo na trdnem zemljinskem sloju. Posedek sloja zemljine pod površjem je sestavljen iz dveh delov: (a) posedka sloja zemljine pod površjem, ki je enak posedku glave pilota brez deformacij v geosintetiku (b) ugrezka sloja zemljine pod površjem zaradi deformiranja geosintetika, pri čemer je upoštevana deformirana oblika za geosintetik enaka obliki deformacije vrvi. Enačba za največji diferencialni posedek med površino podlage in piloti je dobljena s pomočjo analize ravnotežja sil geosintetika in razmerja napetost-specifična deformacija geosintetika na robu glave pilota. Za preveritev predlagane metode je bila izvedena primerjava izračunanih rezultatov z opazovanimi podatki in šestimi trenutnimi analitskimi metodami. Z uporabo predlagane metode je bil preučevan vpliv natezne togosti geosintetika, kompresijskega modula mehke zemljine, debeline mehke zemljine, višine nasipa, notranjega kota trenja nasipnega materiala in razmika pilotov na reakcijo zemljine, razmerja koncentracije napetosti (SCR) in napetosti geosintetika. Učinek teh faktorjev je bil raziskan z uporabo teorije vrednotenja binarne analize variance za neponovljive preizkuse, kar pomaga optimirati načrtovanje PGRS nasipa. |
