| The topographic and geological condition in the western mountainous area in our country is so complicated that there are many cutting and tunnel engineering while highway is constructed. In order to make full use of the waste rocky slag and reduce the damage to environment and cause geologic hazard, the high rock fill embankment has become one of the basic types of embankment structure. But corresponding design method and theory on these are lack, especially in complicated environment. Therefore, in this paper, combing with Gangou high rock fill embankment which high exceeds 70m in Hurongxi express highway, by means of laboratorial experiment, field experiment and monitoring, theoretical research and numerical calculation, the basic performance, the stability and settlement prediction theory, the controlling technology and standard for high rock fill embankment are researched and discussed. The main contents completed are as follows.(1)Aiming at tunnel waste slag as embankment filling material, fractal dimension is introduced to evaluate its granulometric composition. While the fractal dimension distributes from 1.887 to 2.631, the graduation is well and meet the requirement;(2)The method to calculate the field density of rock filling material by mass percent of over size measuring in field revising the density in the laboratorial experiment with suitable size is put forward, which provide a new method for compactness calculating;(3)By establishing rock fill embankment and vibratory roller system with 2 degree of freedom and completing field experiment, the vibratory roller operating with low frequency high amplitude is favorable for compacting rock fill embankment.(4)Based on ultimate equilibrium theory, applying 4 stability analyzing method, the changing discipline of stability of high rock fill embankment in complex environment influenced by water level, the earth's surface gradient, embankment high and filling courses are systematically researched. safety factor become smaller with water level rising, embankment high heightening, filling high going up and grade becoming steep.the safety factor decline markedly while water level exceed 20m, embankment high exceed 34m, filling high exceed 32m and grade exceed 1:5.(5)The stability of high rock fill embankment changes with filling course. Not only the position with minimum safety factor but also the position with maximum safety factor change should be considered. The minimum safety factor and maximum safety factor change all are key factors in dynamic state monitoring in construction.(6)Aiming at the settlement of Gangou high rock fill embankment caused by embankment weight with steps filling, Compertz Growth Curve is applied to analyze and predict the settlement in whole course. The precision of predicting settlement by Compertz Growth Curve exceeds that by hyperbola;(7)By numerical calculation, the stress and deformation discipline of high rockfill abrupt slope embankment are researched. Both Vertical stress and transverse stress increase with embankment depth. The maximum occur near the earth's surface area where the filling high is the maximum. Abrupt slope high rock fill embankment take places asymmetric settlement at both vertical direction and transverse direction. The asymmetric settlement value become greater with embankment's high increasing, while the transverse deformation become smaller with embankment's high increasing; the more closed, the modulus greater, the transverse deformation discrepancy and Asymmetric settlement become smaller.(8)Combing construction technics with settlement discrepancy to detect compacting quality of rock fill embankment is an effective means. While adopting settlement discrepancy as the standard to quality controlling, 2 mm settlement discrepancy after the vibratory roller with 40 ton exciting force compacted is appropriate.
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