Study On Characteristic Of The Horizontal Frost-heave Forces Behind The L-type Retaining Wall

Abstract:In this paper, considering various internal and external factors on the process of frost-heaving, studies conducted on the characteristics of horizontal frost-heaving force behind the L-type retaining wall, including the monitoring of laboratory tests carried out according to a similar principle and numerical simulation to which the laboratory tests acted as a precondition. Through laboratory tests, the value and distribution of horizontal frost-heaving force were monitored, in this process the thermophysical properties influencing the soil frost-heaving characters were studied; through finite element numerical simulation software, temperature fields and horizontal frost-heaving force were calculated based on the frost-heaving test, in this process the selected parameters were discussed. Numerical simulation is more controllable compared to laboratory tests, and the comparison of calculation results using different parameters is easier to implement. But laboratory tests are closer to the real situation and more accurate and credible. The main contents of this paper include:1) A versatile frost soil experiment-chamber which can cool the frost soil from four directions was developed, a indoor horizontal frost-heaving force testing method was designed. During the indoor test of characteristics of horizontal frost-heaving force behind the L-type retaining wall, tester can separately control the temperature changes of embankment top surface, embankment underside and the back of the retaining wall.2) Variation laws of the temperature field was monitored in versatile frost soil experiment-chamber depended on different moisture content, impact factors of the freezing depth were summed up, freezing front evolving graphics were drawed in bidirectional freezing condition. The value and distribution of horizontal frost-heaving force was monitored in versatile frost soil experiment-chamber depended on different moisture content, the development law of horizontal frost heaving force at different height was summed up, and the formula of horizontal frost heaving force was derived from the mechanical point of view.3) Abaqus simulation software was used to simulate the variation laws of the temperature field at different moisture content. Different moisture contents of fine sand were selected to simulate the values and distribution of horizontal frost-heaving forces via changing the temperature field, finally got the relationship between moisture content and the corresponding horizontal frost-heaving forces; the relationship between retaining wall rotation angles and the corresponding horizontal frost-heaving forces was also got by constantly changing frost-heaving constraint condition rendered by the wall.4) The results of both measured and simulated were compared and summarized, the generation conditions and weaken measures of horizontal frost-heaving force were analysed, some suggestions about L-type retaining wall designation were given, factor analysis relating with mathematical theory was promoted.