Increasing Slope Angle Research Articles

Landslide Runout Distance Prediction of Pinousuk Gravel Slope in Mesilou Kundasang, Sabah Using Slope Characterization

The study area is located at Mesilou, Kundasang, which focuses on slopes of the Late Pleistocene Pinousuk Gravel unit. This study aims to determine the landslide runout distance (L) against the slope height (H), slope angle (θ), percentage of sand and clay of slope materials. Data were obtained from a shaking table instrument used to simulate earthquake tremors that resulted in landslides. The results show that the higher the slope it is, the farther the runout will occur with correlation, R = 0.87. Based on the slope failure model, the increase of slope angle will add to 60% of the runout distance with R = 0.81, while the longer time of the tremor received increases more than 120% of the distance from the previous point. Results also show insignificant correlation between clay percentage with runout distance (R = 0.23) while higher percentage of sand shows a greater distance from the slope. The greater distance of movement was due to its incohesive and unconsolidated characteristics with correlation, R = 0.64. All the findings show that slope characteristics, such as slope geometry and slope soil properties, influence the distance of landslide runout.

Effective Prediction of Monthly Heat Transfer Characteristics in a Thin-Layer Cascade Reactor Subjected to Outdoor Conditions

Algal biofuels are intriguingly a renewable energy source that could partially substitute fossil fuels, but further research is required to optimise the growth parameters and establish competitive large-scale cultivation systems. Algal growth is directly dependent on momentum, heat, and mass transfer within the photobioreactor and environmental conditions. Therefore, in this computational study, the heat transfer between the thin-layer cascade (TLC) reactor and its surrounding was reported based on static (location and reactor geometry) and dynamic (air temperature, solar irradiance, and wind velocity) parameters. The resulting model was validated using experimental data. The Nusselt number and the monthly average water temperature were computed to investigate the heat transfer phenomena between the TLC reactor and atmosphere. In addition, a novel corelation was used to estimate the evaporative losses from the TLC reactor. The effect of geometric properties (inclination angle of the reactor, water depth, and channel width) was evaluated on heat transfer. Results showed that heat transfer rate and the optimum water temperature for algal growth were significantly affected by hydrodynamics, environmental conditions, and reactor design. Water temperature decreased with the increase in channel width, water depth, and slope angle of the reactor. Furthermore, algal productivity declined with the increase in the amount of evaporated water.

Theoretical model to estimate the storage volume of rolled erosion control products/geomeshes

Storage effect created by cross laid weft yarns of runoff erosion control geomeshes has a significant influence on their performance. A theoretical model was proposed (prism model) in the recent past to evaluate the storage volume of the geomeshes (micro-barriers), but it has the limitation that is has not considered the warp and weft yarn interlacement. Therefore, a revised pyramid storage model is formulated in this paper by considering the yarn interlacement. To validate the proposed model, plain woven geomeshes are subjected to runoff erosion test at different slope angles (soil slope) in a bench-scale setup. Variation between experimental culmination and calculated culmination due to storage effect is compared by its percentage difference. It is observed that percentage difference between experimental culmination and calculated culmination is lower for proposed pyramid model at all slope angle and mass. It is also observed that at increased slope angle, percentage difference between calculated storage volume and experimental result increases for both pyramid and prism storage model, due to the reduced storage volume. In addition, pyramid storage model has been formulated for different open weave geomeshes by considering the weft yarn interlacement and float length. Theoretically, it is observed that initial increase in float length shows a significant increase in storage volume, but further increase in float length results in a limited increase in storage volume. The results correlate with the past studies on different woven geomeshes. Hence, the proposed storage model with consideration of yarn interlacement and weave can be used for optimising the performance of geomesh at different soil slope angles.

Hydrodynamic analysis and flame pulsation of continuously spilling fire spread over n-butanol fuel under different slope angles

A self-developed laboratory-sized spilling trench is used to study the characteristics of continuously spilling fire spread over n-butanol fuel under different slope angles (0°, 1°, 2°, 3°, 4°) and discharge rates (0–500 mL/min). The hydrodynamic analysis is conducted to account for the variation of flow parameters of unburned liquid based on the theory of open-channel gradual flow. The spill flow velocity increases whereas the thickness of fuel layer decreases along the inclined spilling trench. The flame height versus discharge rate is divided into three regimes, namely the increasing regime at Q < 165 mL/min, the decreasing regime at 165 ≤ Q < 370 mL/min, and the stable regime at Q ≥ 370 mL/min, where Q is the discharge rate. The effect of discharge rate on flame height is related to the heat transfer of fuel surface. With an increase in discharge rate or slope angle, the oscillatory pattern of spilling fire changes from “jumping-retreating-crawling” to “jumping-crawling” and eventually to “uniform”. The velocity of spilling fire is strongly enhanced by the slope angle and the discharge rate because the fuel vapor is driven by dragging effect of no-slip boundary condition on the liquid surface.

A database of landslides triggered by 2014 Mw 6.1 Jinggu earthquake, China

On October 7, 2014, a Ms 6.6 earthquake occurred in Jinggu County, Yunnan Province, China, causing some casualties and property damage. A database of landslides was created based on high-resolution satellite images taken before and after the earthquake. The results show that this event triggered at least 441 coseismic landslides, with a total area of 1.08 km2, distributed in the VII-VIII intensity zone, with an area of about 2160.86 km2. The total volume of these landslides is estimated to be 9.4×106 m3 according to the area-volume formula. The point density, area percentage, and volume density of the landslides in the study area are 0.20 km−2, 0.05%, and 0.004 m, respectively. The comprehensive results show that the Jinggu earthquake landslides are mostly relatively small-scale and develop in a wide range. We consider the influence of topographic factors and river systems on coseismic landslide distribution using landslide number density (LND) and land area percentage (LAP). It indicated that LND and LAP generally increase as the elevation and distance to watershed decrease and slope angle increases and are relatively larger in southeast-facing and concave slopes. This detailed coseismic landslide database for the Jinggu earthquake is essential for the subsequent regional risk assessment.

Stability and parameter sensitivity of a large-scale waste dump in China

Waste dump stability has long been a major concern in open-pit mine production. This paper describes the landslide morphology in detail, based on a summary of the geological conditions of the Dagushan Waste Dump. The modified Mohr–Coulomb strength criterion, which is more suitable for the deformation and failure behavior of waste materials, was adopted based on the limit equilibrium theory to study waste dump stability under complex working conditions such as dumping, vibration, and basement softening, as well as the parameter sensitivity of the main influencing factors. The test results revealed that: (1) the safety factor of the Dagushan Waste Dump first decreased from 1.343 to 1.238 when the waste dump increased from +150 m to +201 m. Thereafter, it decreased from 1.238 to 1.129 because of the weakened basement of silty clay. Afterward, it decreased from 1.129 to 1.029 because of the toe excavation of the waste dump. Finally, the mechanical vibration at the slope toe made the safety factor of the waste dump change periodically every 6 s. The lowest safety factor of the waste dump under mechanical vibration was 0.747, which can eventually result in landslides. (2) The dump stability was moderately sensitive to the third-grade slope angle, basement cohesion, and mechanical vibration strength; however, it was highly sensitive to the third-grade slope height, basement friction angle, basement moisture content, and first-grade slope excavation angle. The dump stability decreased with an increase in the third-grade slope height and angle, basement moisture content, first-grade slope excavation angle, and mechanical vibration strength. The dump stability increased as the basement friction angle and basement cohesion increased. (3) Slope reshaping is proposed as a remedial measure because it was discovered to be effective in maintaining slope stability. These results can be used as a reference point for further dump stability studies.

Stability evaluation method for assessing bedrock and overburden layer slope (BOLS) under seismic load

Seismic load is a type of dynamic load that can easily induce the failure of the foundation slope. Using the continuum-based discrete element method in continuum mechanics, herein, the rupture degree and permanent displacement are defined and their evaluation steps are proposed. The sensitivity of rupture degree and the permanent displacement of overburden under seismic force are also analyzed. A new stability evaluation method for an overburden layer under seismic load, which considers rupture degree and permanent displacement, is established. The results showed that the overburden layer and the interface between bedrock and overburden are damaged to a certain extent under the action of a small-intensity earthquake (a peak = 0.03–0.06 g), although the overburden surface is not damaged. With the increase of seismic frequency and slope height, the permanent displacement of overburden decreases, although it increases with the increase of peak acceleration and slope angle. Furthermore, duration has little to no influence on the permanent displacement of the overburden under the condition of a small or moderate earthquake. In the case of a large earthquake, the permanent displacement of overburden increases linearly with the increase in duration.

Optimum Investigation LED Bulbs Light as Photon Energy on Photovoltaic Panel Installed Inside Buildings

This study was conducted to obtain the angle of elevation of solar panels (PV) to harvest photon light energy sources from LED bulbs that are often used in residential homes or buildings. The PV tilt angles tested are 0, 15, 30 and 90º by placing a constant bulb in its position. The results of the observations show that a slope of 0º produces the highest PV electrical power, although it is not significant compared to the other 3 slope angles. The decrease in PV output power occurs when the slope angle increases. Optimum power of 16.93 Watt is obtained by using a Hannochs bulb at a power of 15 Watt with an angle of elevation of 0º. Furthermore, the power decreased to 16.33, 12.92, and 12.91 Watts at angles of 15, 30 and 90º, respectively. Further research is still needed by increasing the variation of bulb power above 15 Watts to validate the position of the PV panels on the walls of the building according to light source.&#x0D;

107. Cervical alignment and distal junctional failure in posterior cervical fusion: a multicenter comparison of two surgical approaches

<h3>BACKGROUND CONTEXT</h3> Posterior cervical fusion (PCF) is successfully used to treat cervical spondylotic myelopathy, multilevel cervical stenosis, and cervical deformity. However, limited evidence exists regarding the appropriate level of proximal and distal extension of PCF constructs. Further investigation is required to understand the effects of construct endpoint on fusion rate, junctional failure, and sagittal deformity correction. <h3>PURPOSE</h3> To compare the surgical and radiographic outcomes of patients undergoing posterior cervical fusion (PCF) with constructs extending from C2-T2 to patients with constructs extending from C3-T1. <h3>STUDY DESIGN/SETTING</h3> This was a multicenter retrospective review of two prospective cohorts of patients undergoing PCF from C2-T2 or C3-T1 for subaxial cervical stenosis at two academic institutions from 2012 to 2020. <h3>PATIENT SAMPLE</h3> We identified 106 patients for inclusion in the C2-T2 cohort and 49 patients for inclusion in the C3-T1 cohort. <h3>OUTCOME MEASURES</h3> Pre- and postoperative cervical alignment parameters, distal screw loosening, distal junctional failure, and pseudarthrosis were measured. <h3>Methods</h3> Cervical alignment parameters were measured on both preoperative and postoperative radiographs performed greater than 6 months postoperatively. The cohorts were compared based on preoperative cervical alignment, postoperative cervical alignment, and change in cervical alignment. Postoperative radiographs were also assessed for signs of distal screw loosening, distal junctional failure, and pseudarthrosis. We utilized Student's t-test to compare all means between groups with p<0.05 deemed statistically significant. <h3>Results</h3> A total of 155 patients were included in the study (C2-T2: 106 patients, C3-T1: 49 patients). There were no significant differences in demographics or preoperative symptoms between cohorts. Fusion rates were significantly higher in the C2-T2 (93%) than the C3-T1 (80%, p=0.040) cohort. When comparing the C2-T2 to the C3-T1 cohort, the C3-T1 cohort had a significantly greater rate of proximal junctional failure (2% vs 10%, p=0.006), distal junctional failure (1% vs 20%, p<0.001) and distal screw loosening (4% vs 15%, p=0.02). Although ΔC2-7 Sagittal vertical axis increased significantly in both cohorts (C2-T2: 6.2°, p=0.04; C3-T1: 8.4°, p<0.001), correction did not significantly differ between groups (p=0.32). The C3-T1 cohort had a significantly greater increase in ΔC2 Slope (8.0° vs 3.1°, p=0.03) and ΔC0-C2 Cobb angle (6.4° vs 1.2°, p=0.04) <h3>Conclusions</h3> In patients undergoing PCF, a C2-T2 construct demonstrated lower rates of pseudarthrosis, DJF, PJF, and compensatory upper cervical hyperextension compared to a C3-T1 construct. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Buckling Stability Analysis for Piles in the Slope Foundation Based on Cusp Catastrophe Theory

The aim of this paper is to analyze the buckling stability problem for piles in the slope foundation based on cusp catastrophe theory. Formulation of critical buckling load of piles in the slope foundation is obtained. The influential factors of slope angle, distribution of landslide thrust behind the pile, pile-embedded ratio, pile constraints, pile-side friction, pile-side soil resistance, and pile socketed ratio upon buckling stability characteristic for piles in the slope foundation are examined. The results reveal that when pile diameter remains unchanged, critical buckling load increases with the increase of pile length when pile-embedded ratio reaches 60%. When pile length remains unchanged, critical buckling load increases with the increase of pile diameter. Critical buckling load with the assumption of nonlinear horizontal elastic resistance of pile-side soil in the paper is more close to the value based on horizontal elastic resistance of pile-side soil suggested in the code. When slope angle increases, decreased extent of buckling critical load for piles 30–60 m in length is more obvious than the piles which are 10–30 m in length. Strengthening of pile constraints and increase of pile-embedded ratio and socketed ratio are helpful to pile critical buckling load increase. The influential factors of pile-side friction and landslide thrust behind the pile upon pile critical buckling load are tiny and can be neglected.

Hydrological control of soil thickness spatial variability on the initiation of rainfall-induced shallow landslides using a three-dimensional model

Thickness and stratigraphic settings of soils covering slopes potentially control susceptibility to initiation of rainfall-induced shallow landslides due to their local effect on slope hydrological response. Notwithstanding the relevance of the assessment of hazard to shallow landsliding at a distributed scale by approaches based on a coupled modelling of slope hydrological response and slope stability, the spatial variability of soil thickness and stratigraphic settings are factors poorly considered in the literature. Under these premises, this paper advances the well-known case study of rainfall-induced shallow landslides involving ash-fall pyroclastic soils covering the peri-Vesuvian mountains (Campania, southern Italy). In such a unique geomorphological setting, the soil covering is formed by alternating loose ash-fall pyroclastic deposits and paleosols, with high contrasts in hydraulic conductivity and total thickness decreasing as the slope angle increases, thus leading to the establishment of lateral flow and an increase of pore water pressure in localised sectors of the slope where soil horizon thickness is less. In particular, we investigate the effects, on hillslope hydrological regime and slope stability, of irregular bedrock topography, spatial variability of soil thickness and vertical hydraulic heterogeneity of soil horizons, by using a coupled three-dimensional hydrological and a probabilistic infinite slope stability model. The modelling is applied on a sample mountain catchment, located on Sarno Mountains (Campania, southern Italy), and calibrated using physics-based rainfall thresholds derived from the literature. The results obtained under five simulated constant rainfall intensities (2.5, 5, 10, 20 and 40 mm h−1) show an increase of soil pressure head and major failure probability corresponding to stratigraphic and morphological discontinuities, where a soil thickness reduction occurs. The outcomes obtained from modelling match the hypothesis of the formation of lateral throughflow due to the effect of intense rainfall, which leads to the increase of soil water pressure head and water content, up to values of near-saturation, in narrow zones of the slope, such as those of downslope reduction of total soil thickness and pinching out of soil horizons. The approach proposed can be conceived as a further advance in the comprehension of slope hydrological processes at a detailed scale and their effects on slope stability under given rainfall and antecedent soil hydrological conditions, therefore in predicting the most susceptible areas to initiation of rainfall-induced shallow landslides and the related I-D rainfall thresholds. Results obtained demonstrate the occurrence of a slope hydrological response depending on the spatial variability of soil thickness and leading to focus slope instability in specific slope sectors. The approach proposed is conceived to be potentially exportable to other slope environments for which a spatial modelling of soil thickness would be possible.

Characteristics of Breaking Wave Forces on Piles over a Permeable Seabed

Most offshore wind turbines are installed in shallow water and exposed to breaking waves. Previous numerical studies focusing on breaking wave forces generally ignored the seabed permeability. In this paper, a numerical model based on Volume-Averaged Reynolds Averaged Navier–Stokes equations (VARANS) is employed to reveal the process of a solitary wave interacting with a rigid pile over a permeable slope. Through applying the Forchheimer saturated drag equation, effects of seabed permeability on fluid motions are simulated. The reliability of the present model is verified by comparisons between experimentally obtained data and the numerical results. Further, 190 cases are simulated and the effects of different parameters on breaking wave forces on the pile are studied systematically. Results indicate that over a permeable seabed, the maximum breaking wave forces can occur not only when waves break just before the pile, but also when a “secondary wave wall” slams against the pile, after wave breaking. With the initial wave height increasing, breaking wave forces will increase, but the growth can decrease as the slope angle and permeability increase. For inclined piles around the wave breaking point, the maximum breaking wave force usually occurs with an inclination angle of α = −22.5° or 0°.

Experimental assessment of the effective friction at the base of granular chute flows on a smooth incline.

We report on direct measurements of the basal force components for granular material flowing down a smooth incline. We investigate granular flows for a large range of inclination angles from θ=13.4^{∘} to 83.6° and various gate openings of the chute. We find that the effective basal friction coefficient μ_{B}, obtained from the ratio of the longitudinal force to the normal one, exhibits a systematic increase with increasing slope angle and a significant weakening with increasing particle holdup H (the depth-integrated particle volume fraction). At low angles, the basal friction is slightly less than or equal to tanθ.The deviation from tanθcan be interpreted as a contribution from the sidewall to the overall friction. At larger angles, the basal friction μ_{B} saturates at an asymptotic value that is dependent on the gate opening of the chute. Importantly, our data confirm the outcomes of recent discrete numerical simulations. First, for steady and fully developed flows as well as for moderately accelerated ones, the variation of the basal friction can be captured through a unique dimensionless number, the Froude number Fr, defined as Fr=U[over ¯]/(gHcosθ)^{1/2}, where U[over ¯] is the mean flow velocity. Second, the mean velocity scales with the particle holdup H with a power exponent close to 1/4, contrasting with the Bagnold scaling (U[over ¯]∼H^{3/2}).

Instrumented model slopes to investigate the effects of slope inclination on rainfall-induced landslides

Rainfall infiltration is considered as one of the most significant factors triggering slope instability as a number of slope failure occurrences have been documented during or immediately after a rainfall. The rainfall-induced slope instability is governed by a complex interaction of topographical, hydrological and geological conditions of the slopes. Hence slope inclination is vital in determining slope stability under rainfall. Although studies have been carried out to investigate the mechanism of rainfall-induced slope failure, limited compelling experimental studies have been conducted on the factors influencing the initiation of slope failure. In this study, instrumented model slopes were subjected to artificial rainfalls to investigate the effects of the slope inclination on slope stability, and a validated numerical model was developed using the test results from the instrumented model slopes. The outcomes of the study prove that the slopes become more susceptible to sudden collapse during rainfall as the slope angle increases. Further, the results highlight that when the slope inclination is 1.2 times greater than the friction angle of the soil, the failure is initiated by the loss of soil suction, and when it is smaller than or equal to 1.2 times the friction angle of the soil, the failure is initiated by the positive pore water pressure developed at the toe of the slope.

Slope angle determines the productivity of edible culms of Sasa kurilensis in a northern Japanese forest

ABSTRACT Despite their potential usefulness as a natural resource, wild edible bamboos tend to be ignored or neglected by foresters, and we know little about how environmental factors determine the productivity of edible culms. Here, to examine determinants for the productivity of edible culms of Sasa kurilensis, 60 survey plots were established in a northern Japanese forest, and annual field surveys were carried out over 3 years. The results show that the density and stem diameter of edible culms were determined by the local density and stem diameter, respectively, of old culms. This indicates that we can predict how many and what kind (thickness) of edible culms will be produced based on information about the demographic properties of old culms. Then, by using the GIS-linked data, the environmental factors that affect the demographic properties of old culms were explored. As a result, slope angle was the most influential environmental factor; that is, the density of old culms decreased but the stem diameter increased along the gradient of increasing slope angle. This indicates that the productivity of valuable culms in flat areas may be low since edible culms with small stem diameter are less valuable for eating. To confirm this, the productivity of valuable edible culms, which have a basal diameter larger than a specified thickness was estimated at each site, and a hump-shaped relationship between productivity of valuable edible culms and degree of slope angle shows that the productivity of valuable edible culms can be maximized at medium slope angle.

Influence of front slope gradient and the angle between tunnel and slope on stability of tunnel portal

Shallow buried and unsymmetrically loaded tunnel is the most common type of mountain tunnel portal. Currently, most of the studies mainly focus on the stability of side slope, while the investigation on the deformation of the front slope after tunnel excavation is relatively less. In this paper, the influence of front slope gradient and the angle between tunnel and slope on stability of tunnel portal was analyzed by FLAC3D. The results show that: When the front slope angle is greater than 40°, the slope deformation caused by tunnel excavation is larger with the increase of slope angle. In order to ensure the safety of construction, we should not only pay attention to the treatment of the front slope before the tunnel excavation, but also pay attention to the monitoring of the front slope deformation during the excavation of the tunnel portal section. And the most suitable entry angle between tunnel axis and the front slope is 0°, which can control the vertical displacement of relatively large deformation. The research conclusions can provide some reference for the excavation and support design of mountain tunnel portal.

Numerical analysis of reinforced embankment slopes made up of pozzolanic waste materials

The paper presents the numerical study of the bearing capacity behavior of the model footing placed on the top of reinforced embankment slopes made up of Pozzolanic waste materials such as fly ash and ground granulated blast furnace slag (GGBFS). The present investigation is aimed at studying the efficacy of the different types of reinforcement (geogrid and rubbergrid) in improving the load bearing capacity of the embankment slopes made up of waste materials. The effect of various parameters such as slope angle, location of the footing with slope crest, embedment depth of the reinforcement is studied on the strength behavior of the embankment. The analysis is carried out on unreinforced fly ash and GGBFS embankments for three slope angles and three locations of the footing with respect to slope crest, i.e., edge distance. The fly ash slopes reinforced with geogrid and rubber grid reinforcement is also analyzed for all the three slope angles and edge distances as that in unreinforced fly ash embankment slope and further, for various embedment depths of the layer of reinforcement. The GGBFS embankment reinforced with geogrid layer is analyzed with respect to critical slope angle and edge distance and optimum embedment depth of the reinforcement deduced from the unreinforced fly ash and GGBFS embankment and reinforced fly ash embankment. The analysis demonstrated that the load carrying capacity of the embankment slope decreases with increase in slope angle and edge distance in respect of unreinforced and reinforced fly ash slope and the optimum embedment depth ratio seems to be 1.2. Further, the rubbergrid reinforcement is found to perform better than the geogrid. The performance of geogrid reinforced GGBFS embankment is also noteworthy. The study underscores the effective utilization of Pozzolanic waste materials as the embankment slope and the rubbergrid derived out of discarded tyres.

Indigenous knowledge of terrace management for soil and water conservation in the Sikkim Himalaya, India

The main objective of this study was to understand the farmer’s indigenous knowledge of terrace management in the Sikkim Himalaya with reference to Rani Khola watershed. Primary data were collected through a mix of questionnaire surveys, focused group discussions, and field observations with a sample size of 300 households. Detailed documentation of the evolution of the terraces and their types, bunding material, types of risers, the relationship of slope and terraces dimensions, soil and water conservation (SWC) practices were performed. Remote sensing data was used to derive information pertaining to elevation, slope and land-use/cover of the watershed. The study reveals that dimensions and types of terraces are subjected to the elevation, slope gradient, local soil and vegetation cover. Leveled terraces were constructed on lower slopes while outward sloping terraces were more common on higher slopes. It was also observed that with the increase in slope angle, width and length of the terraces decreased. Terrace riser height was also correlated with slope; riser height unavoidably increased as slope increased. The study concludes that terraces in the study watershed are effective in reducing the slope gradient and length, and in turn helpful in trapping eroded soil, slowing soil movement and in due course reducing soil erosion and increasing agricultural productivity. It is suggested that for overall management of terraces, it needs to be combined with additional soil and water conservation practices.

Model test and numerical simulation on the dynamic stability of the bedding rock slope under frequent microseisms

Shake table testing was performed to investigate the dynamic stability of a mid-dip bedding rock slope under frequent earthquakes. Then, numerical modelling was established to further study the slope dynamic stability under purely microseisms and the influence of five factors, including seismic amplitude, slope height, slope angle, strata inclination and strata thickness, were considered. The experimental results show that the natural frequency of the slope decreases and damping ratio increases as the earthquake loading times increase. The dynamic strength reduction method is adopted for the stability evaluation of the bedding rock slope in numerical simulation, and the slope stability decreases with the increase of seismic amplitude, increase of slope height, reduction of strata thickness and increase of slope angle. The failure mode of a mid-dip bedding rock slope in the shaking table test is integral slipping along the bedding surface with dipping tensile cracks at the slope rear edge going through the bedding surfaces. In the numerical simulation, the long-term stability of a mid-dip bedding slope is worst under frequent microseisms and the slope is at risk of integral sliding instability, whereas the slope rock mass is more broken than shown in the shaking table test. The research results are of practical significance to better understand the formation mechanism of reservoir landslides and prevent future landslide disasters.

Model Test and Numerical Simulation of Single Pile Response under Combined Loading in Slope

Vertical loads are commonly transferred by piles primarily in the upper structures. However, lateral loads are also significant compared with vertical loads in pile foundation design. Compared with a pile on level ground, there are many particular characteristics in a pile that is on sloping ground. These characteristics depend on the combined loading and the magnitude of the soil lateral displacement. In order to investigate the pile’s bearing characteristics, a model test was conducted and ABAQUS software was adopted to conduct 3D numerical simulation of a single pile with different slope angles under combined loads. The experimental results indicated that (1) the soil pressure along the slope direction was smaller than the other side, resulting in an asymmetry of the slope soil around the pile, and in turn introducing a horizontal thrust to the pile; (2) with the increase of slope angle, the horizontal thrust increased while the single pile’s bearing capacity decreased; (3) the vertical load caused more pile horizontal displacement with the growth of slope angle; and (4) the pile’s moment and the displacement also increased with the growth of the slope angle. The findings in this study can provide a useful reference in the design of piles or anti-slide piles in sloping ground.