Advanced Materials Research Vols. 446-449

Abstract: The simulation of triaxial compression test for reinforced earth is carried out under application of the numerical analysis software PFC2D. Several groups of reinforced earth samples are tested by simulation under same enclosed pressure but different arrangement of reinforcement and vice versa in the state of shear failure and the results of the test is compared with that from macroscopic experiment. The test shows that reinforcement in earth mass leads to remarkable improvement in shear strength and inhibition of movement of particles around reinforcement medium. The tendency of motion between particles grows as enclosed pressure rises but decreases with the increase of reinforcement layer in number. The reinforcement constrains the lateral deformation of sand sample and enhances shear strength. And the effect of enhancement caused by three-layer reinforcement is remarkably better than that by one-layer. Besides if there’s only a single reinforcement layer, the strengthening effect of a layer in the middle of sample height is better than that of a layer at 1/4 height or 3/4 height, which accords with the results from macroscopic experiment.

Abstract: To ensure the non-working wall's slope stability in Weijiamao open-pit mine,the paper analysis the engineering geological condition and hydrogeology condition of Weijiamao open-pit mine's slope,on this basis,combine the typical rocky slope's deformation and failure mode,physical properties of glutenite and weak layer from experiment,determined the latent destruction mode of non-working wall's slope in Weijiamao open-pit mine;calculated the slope's stable coefficient and the stable coefficient after cutting slope and unloading with rigid body limit equilibrium method ;make the numerical simulation of slope stability with FLAC3D,these expound the evolution law of slope rock mass stress field,reveal landslide mechanism of non-working wall,determined the landslide model is along the circular slip surface;basis for the numerical simulation result,puts forward prevention measures by cutting slope and unloading to realize stable slope.All these provide guidance for slope stability in Weijiamao open-pit mine,provide reference for open-pit mine's slope stability.

Abstract: In the coastal areas, deep mixing method or high pressure jet grouting method are usually used to form cement soil during the ground treatment. It’s easy to inflict corrosion damage of cement soil when the underground confined water is connected to the brine. Therefore, research of the cement soil’s durability under the brine erosion is of important significance to engineering. Start from the theory of chemical dynamics and damage mechanics, based on the chemical reaction formula between MgCl2 and the cement soil, with appropriate assumption, the relationship between ion concentration and corrosion time is deduced: (C1/C2)β=t2/t1, that is: when the soil eroded to equivalent mechanic effect, the relationship of corrosion time can be obtained in the solution with high and low concentration. Based on stress strain relationship, incorporate chemical damage factor into compression modulus, suggest certain assumptions, the same relationship between corrosion time and ion concentration is deduced.

Abstract: Based on the actual rainfall data and saturated-unsaturated seepage theory, the change of pore water pressure and volumetric moisture content of carbonaceous mudstone embankment slope were studied under designed rainfall intensity. At the same time, the effect of rainfall intensity change on the slope failure mode and safety coefficient was analyzed. The results of the study show that: Continuous rainfall will make the surface layer negative pore water pressure of carbonaceous mudstone embankment slope loss, and in transient saturation zone the volumetric moisture content reaches the saturated moisture content. Safety coefficient of carbonaceous mudstone embankment slope gradually decreases with the rainfall continuing, potential sliding surface also have the tendency of extending into the embankment.

Abstract: The assessment of settlement deformation of engineered structures under high-speed railway tracks is an important control link in high-speed railway line construction. This paper discusses characteristics of settlement deformation of sections of subgrade, bridges and tunnels, and analyzes the suitability of predictive methods in currently available technical codes and standards based on measured data of settlement deformation. Currently available assessment analysis methods have good applicability for subgrade sections but are not suitable for sections of bridges and tunnels. Suitable assessment analysis methods are proposed and have been successfully applied to settlement deformation of engineered structures under the tracks of high-speed railway lines. The methods suit the characteristics of “small magnitude and large fluctuation” changes of measured settlement deformations taking account of the construction process of the engineered project.

Abstract: In this study, the strain softening behaviors of an overconsolidated silty clay was studied by a ring shear apparatus. The tested results present some different properties with the traditional shear tests. It was found that the silty clay samples with relatively high shear rates are liable to the occurrence of strain softening. With shear rate increasing, both the peak strengths and the post-peak strength reduction become greater. According to the data of deformation and pore pressure measured during the tests, there are two patterns of causing the strain softening of the silty clay. One is related with the contraction of soil specimens; the other is concerned with the generation of negative pore pressure due to the dilatancy of soil body.

Abstract: This paper explains foundation treatment technique of a sluice in Eastern Liaoning province. Because the chamber is situated at the entrance of the Yellow Sea, under the influence of tides, seawater flow backward yearly. Thus the construction project is an extreme significance to national economy and people's living and environmental protection. Due to its special geographical position bordering the estuary, the foundation soil is complex; silt clay distributes widely, silt clay and fine sand layers staggered. Additionally, seismic intensity is eight degrees, so that it is of no engineering geological significance and is not used directly as a stratum. Therefore, for the soil of the chamber, method of reinforced concrete casting pile for reinforcement is used to meet the different requirements of various working conditions.

Abstract: In order to study the transient seepage field of soil slope when the saturated permeability coefficient changes under rainfall infiltration condition, the finite element software is used to build the numerical analysis model, the influence of slope seepage field and pore water pressure caused by the change of saturated permeability coefficient are emphatically discussed. The results show, under the condition of the certain sustained rainfall strength and rainfall duration, the rain water infiltration rate and infiltration depth are proportional to slope soil saturation permeability coefficient; Pore water pressure along the elevation direction shows the characteristic of “two big heads, among small” under the influence of rainfall infiltration.

Abstract: In Wenchuan earthquake, liquefaction phenomena and relevant damage in Chengdu region was extensive. Through field investigation, macro-liquefaction characteristics in Chengdu region are outlined, i.e., (1) Liquefaction zones (belts) mainly were located in Dujiangyan city; (2) Liquefaction has been observed in seismic intensities VI, VII, VIII, IX and X, but mainly concentrated in intensities VII and VIII; (3) Heights of liquefaction water-jet mostly ranged in 1m to 3m, and the highest was more than 10m; (4) The ejected materials in liquefied sites covered many soil categories, nearly 67% of fine sand and 11% of gravel; (5) Liquefaction generally caused ground fissures, but obvious ground subsidence were not detected. Although the ejected materials mainly were fine-grained soil, the actual liquefaction was prevalent gravel soil

Abstract: "Dragon" is an important design theme and image, to be applied in many design fields, so summing up and interpreting relevant issue of dragon connotation can help better application of dragon image in design. This paper tries to expound dragon iconography, archetype and symbolical meanings in terms of etymology, document research and Jung’s psychology theories. In the light of both objective and subjective meanings this paper regards that the essence of dragon which is mythological being in human subconscious imagination symbolizes and integrates the various great power of nature.