The Study Of The Crushing Of Giant Padding Creep Settlement And Its Constitutive Parameters

Because the construction of airport for itself involves wide field,so there are many engineering problems.In southwest China the topography and geological conditions is complex and varied,given priority to mountain hills and valleys.These two factors make design and construction of the airport in southwest China are facing all kinds of engineering problems,which include high quality demand of engineering sites,complicated geological conditions,the great amount of digging and filling stone,the stability of high slope,the control and other issues differential settlement and the settlement of the filling body.In southwest China most of the construction of the airports will have a lot of digging and filling conditions.Because the packing of the padding is often local materials,the filling body is in many cases the field rock that is blasting after the blast by artificial filling and compaction.On the one hand,the composition of such rock of the padding is more complex and has bad grading problems,on the other hand,is influenced by the construction level of the filling,the post-construction settlement of the high fill of the airport often appears larger and uneven.In addition there are many short-term heavy rainfall weather in southwest,and the rainfall distribution is concentrated in one year,so the settlement of collapsible padding is also very prominent,especially in the rock mass of the padding that is easy to soften and broken when come into contact with water.This paper will study and discuss the problem that is creep settlement of the high fill embankment at the airport under the condition of different water content.Firstly we take the sand and mud stone giant grain and gravel of the high fill of Chong Qing airport as the research object,and conduct experiments of the large uniaxial confining compression and screening.According to the results of the screening experiment we calculated the crushing parameter and fractal dimension,and then established a relation with other variables.With two kinds of intelligent algorithm to identify the creep cvisc model parameters,we established a relationship with the relative breakage rate.It is concluded that in other similar conditions,and knowing the relative breakage rate the constitutive parameters can be directly calculated according to the relationship between them.Finally by validating this constitutive parameters with numerical simulation on experimental conditions,it is proved that the identified constitutiveparameters are of availability.Then the airport area channel slot section model is established,and is used to simulate the creep properties of settlement in case of layered and overall constitutive parameters,when the water content is 5 %and 10%.By this way it is proved that the layered constitutive parameters are more rational than the overall constitutive parameters in terms of the prediction of high fill airport after long-term settlement.With the compare of the 5%,10% and 8 %water content,the rationality of the calculation formula of constitutive parameters is verified.