Applied Mechanics and Materials Vols. 477-478

Abstract: The anchor plays a very important role in gravity retaining wall. The displacement of retaining and soil pressure distribution with anchor is different from that without anchor. The numerical simulation software FLAC^3D is used to analysis the soil pressure distribution characteristics of gravity retaining wall. The results show that the anchor plays a supporting role in gravity retaining wall. There is a critical length in the anchor in gravity retaining wall. The soil pressure distribution of gravity retaining wall with anchor does not conform to the classical Coulomb linear distribution theory and more research is needed for the soil pressure distribution theory. The research has important guiding significance on the design and construction development of gravity retaining wall.

Abstract: A new type of gravity retaining wall combining with anchor is developed to support higher embankment. The retaining wall has the advantage of high safety, lateral deformation small, wide applicable range and low requirements for the foundation bearing capacity. The pressure distributions of gravity retaining wall with anchor have changed a lot. The change will have a significant impact on structures. In order to reveal the gravity retaining wall combining anchor pressure distributions, numerical simulation was done. The result shows that it has no obvious differences to its force state when retaining wall is reinforced with horizontal and oblique anchors, The former is applicable to the new embankment retaining wall support and the latter is applicable to the original retaining wall reinforcement.

Abstract: Through tests and application, analyzes influential factors & reinforcement effect and application prospects & economic benefits of cement-soil mixing composite foundation, propounds some points of view for stabilizing & reinforcement soft-soil foundation by cement-soil mixing method especially in Yinchan District combined with constructive situation

Abstract: The mechanical properties of rock experiencing the variation of joint orientation under uniaxial compression condition were simulated in this paper. Numerical simulations on rock sample in uniaxial compression have been conducted to evaluate the effects of joint orientation on the overall mechanical behaviour of jointed rock masses. It was done using the Rock Failure Process Analysis program RFPA^2D. Numerically simulated stress-strain curve, peak stress, peak strain and failure patterns were compared with the corresponding physical tests. Numerical simulations agree well with physical results, it is shown that RFPA^2D is suitable for the analysis of joint orientation effect on rock fracture.

Abstract: Based on the Biots dynamic consolidation equation, the individual contributions of these two compression waves in vertical vibration of water-saturated soils are analyzed. The equation belong to displacements of solid skeleton is established by using the decoupling of dynamic equation which is combined with boundary conditions to derive an analytic solution about displacements of solid skeleton under the excitation of the individual contributions of these two waves. And then, displacements of pore fluid and pressure of pore water under the excitation of the individual contributions of these two waves are obtained on the basis of that analytic solution. The attenuation of these two types of compression waves influenced by pore permeability is examined and it should be mentioned that, the contribution of the second compression wave is the main consideration when permeability coefficient is large, on the contrary, the contribution of different compression wave should be considered on the different soil column height when permeability coefficient is small.

Abstract: Mechanical property of rock is the main research object of rock mechanics. In order to further learn the rheological characteristics of soft fractured rock mass, the creep test of highly-weathered breccia with different water content of 0.65%, 1.88%, 4.03% using low-intensity uniaxial creepmeter developed by Shandong University is processed, and the strain-time curves under different water conditions and the corresponding variation of creep curves with different stress levels and moisture states are obtained. The experimental results show that the higher water content is, the larger creep deformation is and the longer time of creep deformation reaching stable is, in other words, the influence of water content on the rheological characteristics of rock mass is also significant. Finally, the conclusion that softening critical load (long-term strength) and softening critical depth of soft rock are greatly reduced due to the effect of water on rock structure and mechanical parameters is obtained to provide the fundamental reference for the follow-up tests and similar engineering.

Abstract: We established the computational mode for defective piles based on practical engineering problems,and studied the stability of the defective pile in the heterogeneous soil under vertical harmonic loads. We established the dynamical function based on the principle of Energy and Hamilton, and abtained the expressions of critical frequency of defective piles.The results show that, the instability of the defective piles relate to the degree of defect and the location of defect.

Abstract: With the highway subgrade fill increasing, traditional retaining wall cannot meet the requirements for supporting. To meet this requirement, the prestressed opposite-pull retaining wall was put forward. Due to the anchor pull of the new-style retaining wall, its bearing capacity was enhanced, but the stress is not clear. In order to reveal the stress distribution of the prestressed opposite-pull retaining wall, FLAC3D was adept to do numerical simulation on the new-style retaining wall. It simulated three conditions of the wall with no anchor, with anchor but without prestress and with prestressed anchor. The results showed that, after the layout of prestressed anchor, the lateral earth pressure of the region near the anchor increased with the increase of prestress, the lateral earth pressure of the wall is parabola distribution. The lateral earth pressure was larger than that of the wall with no anchor and with anchor but without prestress. The bearing capacity of the retaining wall was effectively improved.

Abstract: ABAQUS finite element analysis software and load - structure method are adapted in this paper and the structure is simplified as a two-dimensional plane model. 25 kinds of working condition including five hole sizes: 0.6m, 1.2m, 1.5m, 1.8m, 2.1m and five hole positions varying from vault to arch springing are studied and the safety factor distribution of lining are obtained. By comparing the safety factor at dangerous section in lining with hole to that in no damage lining , a convenient evaluation method about the effect of hole to lining safety is proposed.

Abstract: In arid and semi-arid areas, water vapor transfer in non-saturated soil is usually more significant. Based on the existing theories such as soil mechanics and fluid mechanic, as well as the features on water vapor transfer in non-saturated soil, a formula to calculate the saturated water vapor pressure in soil void by taking the matrix suction and temperature into account was got, and a mathematical model for the moisture migration with time was deduced which reveals that a water-vapor migration phenomenon is uneven temperature distribution and uneven distribution moisture alone or in combination manifestations.