Numerical analysis of the interaction between composite-pile and slope and parameters optimization

doi:10.21203/rs.3.rs-3395033/v1

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Numerical analysis of the interaction between composite-pile and slope and parameters optimization

https://doi.org/10.21203/rs.3.rs-3395033/v1

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Anti-slide pile is a retaining structure to improve a slope stability, with the advantages of clear force transfer system, simple construction and easy design. In order to maximize pile potential and slope self-bearing capacity, the FLAC3D software and site monitoring were conducted to analyze the interaction between composite-pile and the hydropower slope in Sichuan province. The results show that compared to the ordinary rigid anti‐slide pile, the composite rigid‐flexible anti‐slide pile is more effective in reducing the bending moment, shear force and lateral earth pressure of the pile with partly increasing horizontal displacement of the slope and the pile segment above the slip surface, each taking up 10%, 20%, 13%. The increase of the thickness of flexible material decreases the internal force of the pile finitely and cushion thickness with 40 cm and space of piles with 3m are optimal . The elasticity modulus of flexible material reduces its internal force of pile less than that of the rigid pile.

composite rigid‐flexible anti‐slide pile

parameters optimization

numerical simulation

rainfall

rigid pile

Landslide is one of three geological disasters to result in losses of properties and human lives in recent years (Aleott and Chowdhury 1999; Sassa et al. 2007; Smith et al. 2017 Tang et al. 2019; Yao et al. 2022; Yin et al., 2022.). The independent cantilever beam model was put forward to analyzing the failure modes of soft-hard interbedded anti-dip rock slopes(Yang Liu,2023).The stability of intake foundation pit was analyzed with site monitoring and numerical simulation.

Anti-slide pile is a feasible retaining structure to maintain slope stable. The relative stiffness between rock mass and piles is an important parameter to maximize self-bearing capacity of slope (Dai.2002,Song et al.2012,Lirer 2012, Zheng et al. 2017).

For different geological conditions and project requirement, different types of anti-slide piles are designed to be suitable for slide scale to stabilize slope, such as the common anti-slide pile (CASP), the anchored anti-slide pile (AASP), the combination pile (CP), and h-form type anti-slide pile (hTP pile) (Fig. 1)

Every anti-slide pile has its advantages and is suitable its environmental conditions. The CASP with simple structures and obvious retaining effect is widely employed for small or medium scale landslide and without restrict spacing requirement. (Galli and Prisco, 2013; Zhou et al., 2014; Kourkoulis et al., 2011)

The AASP is a CASP with anchor cable, which is widely used and improves its retaining performance to resist the larger landslide thrust for medium sized landslide.( Kang et al., 2009; Huang et al., 2013).

The CP is developed on the basis of the CASP pile, and is formed by the rigid combination of two rows of piles, such as PASP. When CASP and AASP are used to treat large size landslides for high cost large size landslides, the CP is used frequently in mountain areas for a big landslide thrust (q ≥ 2000 kN/m) high stiffness, little pile displacement and reasonable stress distribution..( Wang .2011; Kim et al., 2012; Stewart et al., 1994 ).

The hTP pile has been developed on the basis of PASP pile for the flexible structure. It is still infancy. (Ou et al. 2012, Yu et al. 2013, Xiao .2010.Zhao B.2017).

The Composite pile composing with EPS (Expanded Polystyrene) and rigid piles is a very potential stabilizing structure to maximize self-bearing capacity and save project cost (Zheng et al. 2017). It has become a hot research topic to harmonize the stiffness between pile and soil to avoid stress concentration and failure. The study especially concerns the retaining mechanism, and its engineering application, especially in construction technology and engineering economy, by relying on the Sichuan hydropower landslide treatment engineering.

The project is located at Diaojiaping village Youxi Town Jiangjin district in Chongqing City as shown Fig. 2. The slope is characterized with comprising sedimentary rock, sloping approximately 20◦ toward the southwest, with elevations ranging from 450 m to 570 m above sea level as shown in Fig. 3. After the excavation of the project, a high slope of 54 ~ 60m was formed, of which the upper slope is about 43m high, and the lower slope is about 16m high after vertical excavation, which is a rock slope. The residual cover layer of the partial slope is the silty clay and crushed stone deposited in the slope, and the thickness is about 2 ~ 2.6m. The soil slope has poor stability. The slope is a second-class general slope with a design safety factor of 1.3.

According to the survey and field investigation, the exposed strata in the study area are mainly the Upper Jurassic Suining Formation (J₃^s) and the fourth series (Q), the cover layer is compactable, highly permeable, and prone to rainfall failure, containing many gravels as shown in Fig. 4.

The main types of quaternary overburden in the study area are: artificial deposit (Q₄^ml), residual slope deposit (Q₄^el + dl), collapse slope deposit (Q₄^{coll + dl}), modern river alluvial deposit (Q₄^3al), Class I terrace (Q₄^1 + 2al), Class II terrace (Q₃^2al), etc.

(1) Manual stacking (Q₄^ml) :

This layer is mostly distributed for houses, railways, highways and other subgrade, lithology is mostly broken stone with silty clay, a small number of bricks, concrete blocks. The composition of the crushed stone is sandstone, muddy siltstone and mudstone, which is accumulated by manual excavation and transportation. The sorting of the crushed stone is poor, the diameter of the block is different, the structure is elevated, the compactness is poor, the content of the crushed stone is about 50 ~ 80%, the thickness is generally 2 ~ 3 m, and the thickness is about 5 m.

(2) Residual slope volume (Q₄^el + dl) :

This layer is mainly brown red silty clay, silty clay gravel, plastic to hard plastic, gravel particle size is less than 2 cm, the content is about 10 ~ 30%, the thickness is generally 1 ~ 3 m, local up to 4 ~ 5 m, mainly distributed in the trough valley, less distributed in the gentle slope of the hill.

(3) Slope collapse (Q₄^col + dl)

This layer is maroon gravel soil, silty clay gravel, gravel particle size more 2 ~ 15 cm, the content is about 30 ~ 60%, the thickness is generally 1 ~ 3 m, local up to 4 ~ 5 m, mainly distributed in the foot of the hill.

(4) Modern river alluvial (Q₄^3al) :

This layer is silt, sand pebble with drift stone, loose, clear water, egg drift stone particle size more than 1 ~ 10cm, the content is about 65%, the thickness is generally 3 ~ 6m, local up to 10m, mainly distributed in the Yangtze River bed and floodplain.

(5) Class I Terrace (Q₄^1 + 2al) :

This layer is silty clay, silt, fine sand, sand pebbles, slightly dense, pebble particle size more 2 ~ 8cm, the content is about 65%, the thickness is generally 10 ~ 25.1m), local up to 31.5m field area mainly distributed along the water diversion pipe surface elevation below 215m.

(6) Class II Terrace (Q₃^2al) :

This layer is a base bench, mainly composed of gravel and gravel soil, medium to dense, pebble particle size of 2 ~ 10cm, a small amount of diameter of about 15cm, the content of about 60%, the thickness of the general 5 ~ 16m, local up to 22.1m (BZK36), drilling revealed the thickness of the cover layer is shown in Table 1.

The bedrock is interbedded with bright purple red, brick red mudstone and argillaceous siltstone, with interbedded sandstone. The content of sandstone is relatively small and the thickness of single layer is less than 3 m, and the sandstone accounts for about 10%. The lithologic phase transformation is large. The pulse width is generally 1 ~ 2 mm, mostly short and poor continuity. Exploration reveals that the thickness of Suining Formation is more than 180 m. Mudstone is about 70%.

Weathering of rock mass can be divided into four weathering zones: full, strong, weak and slight. The thickness of strong weathering zone is 0.0 ~ 4.8 m. The thickness of the weak weathering zone is generally 7.9 ~ 30.0 m, and the thickest is 48.5 m, which is distributed under the strong weathering zone. The depth of breezes is generally large. The weathering of rock mass is mainly uniform. Due to the difference in lithology of sand and mudstone, there is partial differential weathering. Meanwhile, the soft mudstone also has rapid weathering problem, and mudstone will disintegrate after exposure to sunlight and water.

According to the completed borehole wave velocity test results, the integrity coefficient of weakly weathered mudstone is 0.39 ~ 0.79, indicating poor to complete integrity. The integrity coefficient of the breezy mudstone is 0.56 ~ 0.81, which is relatively complete. The integrity coefficient of weakly weathered siltstone is 0.40 ~ 0.64, and the integrity is poor ~ relatively complete. The integrity coefficient of the breezy siltstone ranges from 0.49 to 0.67, indicating poor to relatively complete integrity. The integrity coefficient of weakly weathered sandstone ranges from 0.36 to 0.66, indicating poor to more complete integrity, while that of breezy sandstone ranges from 0.53 to 0.73, indicating more complete integrity.

2.1. Numerical simulation of natural slope stability

The advantages of the composite pile are more than that of common rigid pile. FLAC^3D software was used to calculate the earth pressure to pile and shear force and bending moment of two piles above. The models are as follows in Fig. 5–8.

According to the actual slope information, the slope is divided to three layers: argillaceous siltstone(thickness,7m), weakly weathered sandstone (thickness,30m), weakly weathered mudstone(thickness,35m). It is employed with Mohr-Coulomb Strength criterion. The model is 150 meters long, 50 meters wide and 150 meters high. The surface of the top and slope are free, the displacement of the bottom side is 0 in three directions, and the displacement of the side side is 0 in the horizontal direction, and the vertical is free(Laxman et al. 2022).

Firstly, the slope soil constitutive model is set as MOHR-COULOMB constitutive model, the anti-slide pile is set as elastic constitutive model, and the velocity and displacement of all nodes are cleared to simulate the static equilibrium state under the action of the initial ground stress field (Pirone, M.,2018).

The parameters and geometric dimensions of the rock and soil mass are the same as in Fig. 4. The length of the pile foundation is 40 meters, the cross-section size is 2 meter and 3 meters, the distance between the pile foundations is 3 to 8 meters, and the EPS thickness is 0 to 1 meter.

In this project, we have assumed that the entire precipitation infiltrates into the ground as long as the infiltration rate does not exceed the permeability of the soil. To calculate the overall safety factor, strength reduction method was conducted for three stages. At first, the initial steady-state simulation was carried out to generate the pore water pressure by assigning artificially large cohesion and stress field. Secondly, the cohesion is reduced to the specific site values. At the final step, a verification simulation is used to ensure that the model has attained thermodynamic equilibrium (Wei, W.B., 2009. Zheng, Y.R., 2009. Laxman et al. 2022).

2.2. Site monitoring

To understand harmonization of the composite pile and soil, many monitoring points were placed, including surface displacement, piles displacement and the earth pressure forcing to the piles (Suleiman, M.T., 2015.Guoqing Zhao et al. 2019).

To monitor and understand the slope movement, a network of 15 monitoring points was established on the slope surface seen from Fig. 9, and the first measurement was performed on May 24, 2021

To avoid erosion by weathering and human activity, the monitoring network consists of 5 cm long stainless steel nails (round head with a washer), installed on solid constructions such as sports fields, sidewalks, and tarmac roads as monitoring points. For the monitoring points on the ground, a foundation support made of concrete (50 × 50 cm for the top, 30 × 30 cm for the bottom, and 40 cm for the height) was installed. Since then, the coordinates of each monitoring point have been measured ten times each year. In addition to survey the deformation of the slope surface through the periodical measurements of the ground monitoring points, in situ investigation of geology(Sun, H.Y ,2013.Guoqing Zhao et al. 2019).

Furthermore, to understand the subsurface geology and possible depths of sliding surfaces within the dip slope, rock core data and inclinometer survey results were analyzed. The distribution of monitoring points is seen from Fig. 9.

3.1. the stability of Natural slope and Cutting slope

Without considering the influence of rainfall, the slope displacement after the first four steps of excavation is very small. Thanks to the good rock and soil quality of the upper two layers of the slope, the slope displacement basically changes around 1.3mm. After vertical excavation of weakly weathered mudstone layer, the displacement increases greatly, and the maximum horizontal displacement occurs at the front end of the vertical slope, which is about 3.06cm. The displacement is large, and there is a risk of collapse. The slope needs to be supported at the vertical slope.

Considering the influence of rainfall, the maximum horizontal displacement of the slope after the first four steps of excavation is about 2mm. In addition to the excavation of the slope, there is also a horizontal displacement of about 2mm in the mudstone layer, which does not increase significantly compared with the condition without considering rainfall. After the fifth step of excavation, a vertical slope of nearly 16 m high appeared in the mudstone layer, and the displacement increased rapidly, about 15 cm. It shows that considering the influence of rainfall, the slope displacement is very large, and the instability failure is very likely.

Seen from Fig. 11–12, the displacements and safety factors of the slope are changing with different excavation steps under no-rainfall or rainfall conditions. When the fifth step is finished, the safety reaches the largest for unloading or loading.

3.2 Slope stability reinforced by composite pile and rigid pile

Seen from Fig. 13–15, the displacement of slope is different for different anti-pile and environment conditions. Site-monitoring and numerical simulation were conducted to investigate the long-term deformation of slope (Chia-Han Tseng,2021). Rainfall caused large deformation in location slope while composite anti-pile led to large one in whole slope.Seen from Fig. 16–19, excavation led to the displacement of slope need anti-pile to reduce to different degree according to different types of piles (Jianbing Peng,2019).

When the thickness of EPS cushion H = 0.5m, it can better play the role of flexible support of EPS cushion; when H > 0.5m, it has little influence on the internal force of anti-slide pile; otherwise, it can be seen from Fig. 4–23 that there is still a large space to reduce the bending moment value; when H < 0.5m, it has a greater sensitivity to the internal force of anti-slide pile; when H = 0.5m, The sensitivity to the internal force of anti-slide pile decreases, and the effect of flexible support is weakened by the thickness of EPS cushion. According to Fig. 15–16, the shear force and bending moment are reduced 20% and 10%, respectively.

Under the support of EPS cushion with the same thickness, the change of internal force of anti-slide pile shows the same trend: when pile spacing D is 3 ~ 5m, the change of internal force of anti-slide pile is small; When pile spacing D = 6 ~ 8m, the internal force of anti-slide pile changes greatly and increases obviously.

Under the support of EPS cushion with the same thickness, the change of internal force of anti-slide pile shows the same trend: when pile spacing D = 3 ~ 5m, the change of internal force of anti-slide pile is small; When pile spacing D = 6 ~ 8m, the internal force of anti-slide pile changes greatly and increases obviously.

At the same pile spacing, through data processing comparison, it is found that the internal force changes of anti-slide pile show the same rule: with the increase of EPS cushion thickness, the maximum bending moment value and maximum shear value of anti-slide pile under composite support decrease. However, EPS cushion thickness has limited effect on reducing the internal force of anti-slide pile. With the increase of the thickness, the internal force of anti-slide pile decreases in a trend of first large and then small, as shown in Fig. 29. During the simulation the least earth pressure account for about 87% of natural state under composite anti-slide pile, positively related to the thickness of EPS with some degree.

3.3 Monitoring analysis

Displacement patterns of sliding block from monitoring data are similar to simulation results. The results show that the large displacements of slope surface and pile are increasing greatly during rain seasons (from May to July) and counterpart earth pressure follows the same pattern. At the same time, the displacement of rigid pile is almost two times more than that of composite pile. Those provide that composite pile is more suitable for the slope than rigid pile and give greater play to the bearing capacity of the slope itself.

Potential sliding blocks and geologic structures with time are changing and similar to simulation results.

The monitoring shows that shallow sliding is dominant.

Based on the numerical simulation and site monitoring data, the results are obtained under different conditions in Table 9. Further, the estimated FOS values are analyzed according to Chinese specification design of engineering slope in water resources and hydropower projects SL386-2007, the FOS of the slope is required to be 1.3. Seen from Fig. 12, the FOS values are lesser than required during rainfall, which is 1.17. When anti-pile was situated, the stability of slope is feasible (Chaoning Lin, 2020). However, considering economic conditions composite anti-pile is more reasonable than rigid pile.

4.1 Determination of safety monitoring index for the slope

In this study, the long-term monitoring of the slope surface from May 2021 to Novermber2022 reveals the movement laws of sliding mass, as shown in Fig. 9. In this section, the progressive deformation process of the reinforced slope and shear force and bending moment of piles are studied and discussed. From the monitoring data, it is found that the slope has some safety stock to bear external force and environmental effect. Therefore, yielding support was employed to economize greatly, such as composite pile, which has less displacement at the pile top than rigid pile top. Thus composite pile bears less shear force and bending moment so that some materials was saved and so on, as shown in Fig. 22–25. With the thickness of EPS increases, the displacement of pile decreases and displacement of slope increase accordingly in Table 9.

To observe the behavior of the pile-slope system, a number of monitoring instruments, including displacement of slope and pile top, earth pressure, were installed in the hydropower slope in Chongqing district. Seen from Fig. 9, increasing rate of earth pressure is faster and then slower (Chia-Han Tseng, 2021 ). The displacement of slope and pile top is a same trend and the displacement value of pile top is lager than that of pile top (Chaoning Lin,2020).

4.2 Determination of numerical simulation for the slope

From the numerical analysis, it is found that yielding support was employed to be useful for reducing the internal force and bending moment of pile, earth pressure and increase the displacement of slope, as shown in Fig. 22–31. Meanwhile increasing thickness of EPS is available to slope movement to reduce earth pressure. When the space of piles increases, there are the same laws for slope. However, to some degree the failure of slope takes place. The bearing capacity of the slope mainly depends on the load-carrying capacities of anti-slide piles. Therefore, the shear carrying capacity and the flexural capacity of anti-slide piles are focused. Compared to the displacement of slope and the internal force of piles, the optimal thickness of EPS and space of piles are 40cm and 3m, respectively. Seen from Fig. 22–31, with the increasing of EPS thickness the pressure acting on piles decreases and the shear force and bending moment are similar changing laws (Zheng Junjie, 2017).

The stability of the hydropower slope is a crucial problem in Jiangjin district of Chongqing city, China. In this study, the stability of the slope was analyzed during no-rainfal or rainfall considering cutting slope. At the same time, five types of anti-piles were proposed, such as commom rigid anti-slide pile, anchor anti-slide pile, h-form anti-slide pile, composite anti-slide pile. The common rigid anti-slide pile and composite anti-slide pile were analyzed and the parameters, including the thickness of EPS and space of piles, were optimized

The conclusions are as follows.

(1) After EPS cushion is installed between pile and soil, pile bending moment, shear force and soil pressure at pile side decrease obviously, but the horizontal displacement of pile body free section and fill soil will increase to a certain extent, as shown in Fig. 32.

(2) EPS cushion significantly reduces the internal force and side soil pressure of anti-slide pile within a certain range. But when the thickness exceeds a certain value, the reduction effect of internal force and side soil pressure of anti-slide pile is weakened. Under the support of EPS cushion, the displacement of slope also increases with the increase of EPS cushion thickness. But the safety factor is on the contrary, and the greater the thickness, the worse the supporting effect of anti-slide pile on slope. The specific project needs to consider the influence of the slope deformation after the support of EPS cushion and to strictly control the thickness of EPS cushion, as shown in Fig. 20–31.

(3) The greater the pile spacing, the greater the displacement of the slope. The pile shear and bending moment also increase with the increase of pile spacing, and the increasing rate shows a decreasing trend. The use of composite support requires the selection of reasonable space of anti-slide pile. When the space of anti-slide pile exceeds a certain value, the supporting internal force will be greatly increasing, and the supporting effect will decline faster, as shown in Fig. 20–31.

The methods and results are applicable to other active shallow-slope cases in terms of research and disaster prevention of slope movements.

CRediT authorship contribution statement

Jun Yu: Conceptualization, Methodology, Writing - original draft. Yilin Yao: Software, Experiment, Data curation, Visualization. Cai Yifeng: Data curation, Visualization, Kezhong Wang: Visualization, Investigation. Experiment.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgement

We thank Xiao shiguo professor from southwest jiaotong University in Sichuan for their valuable comments on the research and technical support. This research was supported by the National Natural Science Foundation of China (No.51679215) and Natural Science Foundation of Zhejiang province(No.LGF21E090005). The authors would like to express their sincere gratitude to the editor and three anonymous reviewers for their valuable comments, which have greatly improved this paper.

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Table 1

acoustic wave classification of geotechnical weathering in project area
Weathering band	Rock property	Wave velocity ratio/K_v	Acoustic velocity/m/s
Weathering lithology	mudstone	0.22~0.27	1500~2160
	siltrock		1520~2280
	sandrock		1660~2490
Weakly weathered mudstone	mudstone	0.40~0.79	2000~3828
	siltstone		2222~3847
	sandstone		2439~4167
Breezy mudstone	mudstone	0.56~0.81	2730~3957
	siltstone		2899~4255
	sandstone		3279~4716

Note: Wave velocity ratio K_v is the ratio of wave velocity between weathered rock and fresh rock sandstone.

Table 2

Comparison table between Kv and integrity of rock mass
Degree of completeness	Completeness	Higher than completeness	Lower than completeness	Higher than fragmentation	Fragmentation
Integrity coefficient	K_v≥0.75	0.75 ≥ K_v≥0.55	0.55 ≥ K_v≥0.35	0.35 ≥ K_v≥0.15	K_v≤0.15

Table 3

Classification of rock hardness in the study area
Hardness	Hard rock		Soft rock
Hardness	Hard rock	Harder rock	Softer rock	Soft rock	Extremely Soft rock
R_c(MPa)	R_c>60	60 ≥ R_c>30	30 ≥ R_c>15	15 ≥ R_c>5	R_c≤5
Representative rocks		sandstone	sandstone	argillaceous siltstone	all kinds of strongly weathered rocks

Table 4

Physical and mechanical properties of different strata
name	Weathered state	Particle density	Density			Moisture content	Water absorption	porosity	uniaxial compressive strength
		Particle density	Natural state	Dry state	Saturated state	Moisture content	Water absorption	porosity	Natural state	Saturated state
		g/cm3	g/cm3			%			MPa
argillaceous siltstone	Moderate weathered	2.65	2.44	2.48	2.52	1.79	3.36	8.19	10.4	7.0
sandstone	weakly weathered	2.75	2.50	2.58	2.59	3.13	3.61	9.01	15.9	10.8
mudstone	weakly weathered	2.67	2.51	2.54	2.57	1.29	2.40	6.03	84.1	71.3

Table 5

Parameters of the rigid anti-slide pile
Name	Density/kN/m³	Young^,s modulus/MPa	Poisson ratio	Size/m
the rigid anti-slide pile	2500	30000	0.20		2*3

Table 6

Parameters of the rigid anti-slide pile and EPS cushion
Name	Density/kN/m³	Young^,s modulus/MPa	Poisson^,s ratio	Size/m
the rigid anti-slide pile	2500	30000	0.20	2*3
EPS cushion	900	0.2	0.40	0.3

Table 7

Statistical results of two supporting structures
Reinforced methods	Maximum shear strain increment	Maximum total displacement（mm）	Horizontal earth pressure(kPa)	Safety factor
Rigid pile	5.39E-04	4.39	141	1.36
Composite pile	5.03E-04	4.73	138	1.34
Difference value	3.6E-05	0.34	3	0.02

Table 8

Safety factor statistics under different combinations
Pile space	Rigid support	EPS cushion thickness(m)
Pile space	Rigid support	0.1	0.3	0.5	0.7	1.0
3 m	1.848	1.871	1.889	1.852	1.802	1.785
4 m	1.843	1.854	1.861	1.848	1.795	1.753
5 m	1.840	1.848	1.859	1.835	1.784	1.704
6 m	1.828	1.830	1.833	1.828	1.732	1.685
7 m	1.788	1.749	1.732	1.683	1.668	1.582
8 m	1.714	1.621	1.559	1.532	1.503	1.432

Table 9

Monitoring data of slope and piles
time	Surface displacement of slope(mm)	Horizontal displacement of composite pile(mm)	Horizontal displacement of rigid pile(mm)	Earth pressure acting to piles(kPa)
2021-5-6	7.4	12.1	23.2	76.5
2021-6-6	8.1	14.3	26.3	85.1
2021-7-6	9.3	15.4	28.5	88.9
2021-8-6	10.2	16.2	28.9	91.2
2021-9-6	12.3	17.3	29.5	95.3
2021-10-6	13.4	18.1	30.1	96.4
2021-11-6	14.2	18.9	31.2	98.5
2021-12-6	14.5	19.1	32.1	99.2
2022-1-6	14.6	19.3	32.4	100.1
2022-2-6	14.6	19.7	32.7	100.5
2022-3-6	14.9	20.3	32.9	101.6
2022-4-6	15.2	20.8	33.4	101.8
2022-5-6	16.1	21.9	35.6	102.3
2022-6-6	16.3	22.3	37.1	104.5
2022-7-6	17.1	23.5	38.4	105.7
2022-8-6	18.9	24.3	39.8	106.4
2022-9-6	19.1	25.3	40.1	106.7
2022-10-6	19.2	25.8	40.4	107.1
2022-11-6	19.3	26.1	40.5	107.6

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Editorial decision: Reject after review
10 Feb, 2024
Reviewers agreed at journal
15 Nov, 2023
Reviewers invited by journal
30 Oct, 2023
Editor invited by journal
09 Oct, 2023
Editor assigned by journal
08 Oct, 2023
First submitted to journal
04 Oct, 2023

You are reading this latest preprint version

Numerical analysis of the interaction between composite-pile and slope and parameters optimization

Status:

Version 1

Abstract

Figures

0. Introduction

1. Study area

2. Methodology

2.1. Numerical simulation of natural slope stability

2.2. Site monitoring

3. Results and discussion

3.1. the stability of Natural slope and Cutting slope

3.2 Slope stability reinforced by composite pile and rigid pile

3.3 Monitoring analysis

4. Results and discussions

5. Conclusions

Declarations

References

Tables

Status:

Version 1