scholarly journals A Study on Correlation between Pore Water Pressure, Rainfall and Landslide Occurrence

2013 ◽  
Vol 4 (2) ◽  
pp. 24-27
Author(s):  
Suhaimi D.N.A.A ◽  
Selaman O. S.
Keyword(s):  
Pore Water ◽  
Heavy Rainfall ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Microsoft Excel ◽  
Exponential Relationship ◽  
Saturation Condition ◽  
Landslide Occurrence ◽  
The Road ◽  
Landslide Event

Landslides not only include loss of human lives and properties, but also effect the transportation direct and indirectly. This study focus on the correlation between rainfalls and pore water pressure which lead to landslide event. For this study, the scope of study focuses at Bau, Sarawak whereby lot of landslide event occurs along the road in 2009. Triaxial test is conduct in lab to measure pore water pressure which modeling landslide occurs on 11th January 2009 at KM 72.00 Bau-Lundu Road. From the laboratory test, it can be seen that continuous and heavy rainfall will increase the pore water pressure in soil. When the pore water pressure increase from 809.94 kPa to 829.25 kPa, the strength of the soil will be decrease due to the water content inside the soil. Other than that, correlation between pore water pressure and rainfall can be seen as an exponential relationship by plotting agraph using Microsoft Excel. It indicates that continuous rainfall within 11 days will increase the changes in pore water pressure and causes the soil to be in fully saturation condition. After 27 hours, the soil will be in failure which leads to landslide.

scholarly journals Study on Seepage Laws of Completely Weathered Phyllite Slope Under Rainfall

2020 ◽  
Vol 145 ◽  
pp. 02003
Author(s):  
ChaoQun Liu ◽  
XiaoMing Huang ◽  
Dan Liu ◽  
LiQing Zhu ◽  
Yang Sun
Keyword(s):  
Pore Water ◽  
Heavy Rainfall ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Sensor Data ◽  
Moisture Sensor ◽  
Soil Moisture Sensor ◽  
Artificial Rainfall ◽  
Shallow Layer ◽  
Back Edge

According to the available geological data and monitoring data, the completely weathered phyllite slope dilates and softens under the condition of continuous rainfall, which is then prone to instability failure. The indoor artificial rainfall test was carried out through the construction of the slope model, and the soil moisture sensor, pore water pressure sensor and matric suction sensor were used to study the variation laws of moisture content, pore water pressure and infiltration line at the back edge, slope body and the foot of the slope under continuous heavy rainfall. According to the sensor data and recorded information, with the influence of heavy rainfall over a long period of time, the water content and pore water pressure increased firstly, then decreased, and finally stabilized. The infiltration line moved from the top, the surface and the foot of the slope to the slope body, and shallow slip failure occurred in the shallow layer of the slope body.

scholarly journals A Numerical Investigation of the Deformation Mechanism of a Large Metro Station Foundation Pit under the Influence of Hydromechanical Processes

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Yan Wang ◽  
Yongjun Zhang ◽  
Mingfei Li ◽  
Yi Qi ◽  
Tianhui Ma
Keyword(s):  
Pore Water ◽  
Heavy Rainfall ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Ground Surface ◽  
Horizontal Displacement ◽  
Horizontal Distance ◽  
Foundation Pit ◽  
Metro Station ◽  
Ground Conditions

Considering the unique conditions of deep and large subway foundation pit excavation affected by heavy rainfall in soil-rock composite strata, this paper employs finite element numerical simulation methods to study foundation pit instability under the influence of heavy rainfall. According to the hydraulic coupling conditions caused by rainfall, a fluid-solid coupling numerical model for a deep and large subway foundation pit in soil-rock composite strata is established in this paper. By selecting the Anshan road station of Qingdao subway line 4 as the engineering background, various parameters related to foundation pit excavation affected by heavy rainfall at different excavation depths were analyzed. The study found that after the foundation pit was excavated, the surrounding pore water pressure decreased and the pore water pressure near the ground surface increased rapidly due to rainfall. As the horizontal distance from the foundation pit increased, the pore water pressure at the same depth also increased. The excavation of the foundation pit caused uplift of the bottom of the pit. After rainfall, the uplift value decreased compared with that before rainfall. With increasing excavation depth, the decreased value of the bottom uplift decreased and then increased. The rainfall caused the horizontal displacement of the pit walls on both sides of the pit to increase. When the excavation depth was 10 m, the horizontal displacements on both sides of the pit were equivalent. When the excavation depth was 20 m, the horizontal displacement was concentrated in the first 10 m; when the excavation depths were 30 m and 40 m, the horizontal displacement was concentrated in the first 13 m. This finding shows that when the foundation pit was affected by rainfall, the sidewall collapsed at a distance of 13 meters from the ground. As the excavation depth increased, the depth of excavation instability was closer to the bottom of the pit. The research in this paper can provide a reference for the construction of deep and large foundation pits in similar composite ground conditions that are affected by rainfall.

scholarly journals Discussion on the Characteristics of Seismic Signals Due to Riverbank Landslides from Laboratory Tests

Water ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 83
Author(s):  
Zheng-Yi Feng ◽  
Chia-Ming Hsu ◽  
Shi-Hao Chen
Keyword(s):  
Water Content ◽  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Water Levels ◽  
Seismic Signals ◽  
Transform Method ◽  
Frequency Distributions ◽  
Landslide Event ◽  
Self Potential

Floods and erosion often cause landslides of riverbanks and induce problems such as river blockage, shift of river center, or flooding from rising riverbeds. Instrumentation and monitoring are often used to explore landslide and erosion behavior of riverbanks. Therefore, this study identified landslide types and characteristics of their seismic signals due to toe erosion of riverbanks through riverbank models with various instrumentation sensors in a laboratory flume. To induce landslides in the riverbank model, a test was set up for water to flow through the toe of the riverbank model. Seismic signals of each landslide event were measured during the tests with accelerometers. Nonpolarized electrodes were installed for observing the self-potential changes during the test. Water content and pore water pressure gauges were installed in the riverbank model. In addition, water levels were recorded. The Hilbert–Huang transform method was used to analyze the characteristics of seismic signals caused by water flow and riverbank landslides. Time points, landslide frequency distributions, and the characteristics of several landslide events in the riverbank models were estimated using the seismic signals. This study identified three types of landslides: single, intermittent, and successive. Moreover, changes in self-potential signals, pore water pressure, and water content during the tests were examined and were found to correspond to the landslide process of the riverbank model.

scholarly journals Influence of pore water pressure on landslide occurrence.

Landslides ◽  
1987 ◽  
Vol 24 (2) ◽  
pp. 2-9 ◽  
Author(s):  
Shoji OGAWA ◽  
Toshio IKEDA ◽  
Takeshi KAMEI ◽  
Hiroaki SANO
Keyword(s):  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Landslide Occurrence

Determining Range of Saturated Ground around Leakage Pipeline Using Unsteady Seepage Numerical Analysis

2012 ◽  
Vol 204-208 ◽  
pp. 609-613
Author(s):  
Xing Gao Li ◽  
Chao Jie Duan
Keyword(s):  
Numerical Analysis ◽  
Hydraulic Conductivity ◽  
Water Content ◽  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Injection Well ◽  
Exponential Relationship ◽  
Seepage Analysis ◽  
Conductivity Function

It is of great significance to estimate the range of saturated ground around leakage pipelines when tunneling near the pipelines. The range of saturated ground can be determined from the distributions of the water content and pore-water pressure in ground around the leakage pipelines. The leakage pipeline being modeled as an injection well, a series of unsteady seepage numerical analysis is performed to understand the effects of the internal water pressure of pipelines on the range of saturated ground surrounding the pipelines, and computation results show the exponential relationship between them. In the unsteady seepage analysis, the hydraulic conductivity function and the volumetric water content function must be determined beforehand to get reasonable results of the range of saturated ground.

Investigation of the Pore-Water Pressure of Saturated Warm Frozen Soils Under a Constant Load

2016 ◽  
Vol 138 (6) ◽  
Author(s):  
Hu Zhang ◽  
Jianming Zhang ◽  
Zhilong Zhang ◽  
Mingtang Chai
Keyword(s):  
Pore Water ◽  
Peak Pressure ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Constant Load ◽  
Exponential Relationship ◽  
Frozen Soils ◽  
Excess Pore Water Pressure ◽  
External Loads

A series of compression experiments was conducted to observe the pore-water pressure variations of saturated warm frozen soils over time. The results indicate that saturated warm frozen soils can exhibit excess pore-water pressure when subjected to external loads. The pore-water pressure fluctuates rather than varying monotonically, and it gradually increases with increasing compressive deformation as the pores are compressed. Furthermore, the permeability of the soil allows pressure dissipation. Thus, the pore-water pressure is continuously changing because of the interactions between these two opposing processes. The peak pore-water pressure follows an exponential relationship with the soil temperature and decreases to a steady value as the temperature decreases. A dissipation trend is observed after the peak pressure is reached. This trend reflects the influence of consolidation in the deformation of warm frozen soils. As the temperature increases, the role of the consolidation becomes more significant.

scholarly journals Influence and evaluation of saturated soil shield construction on existing highway

2020 ◽  
Author(s):  
Liuqi Xu ◽  
Chongfu Wu ◽  
Liwei Wang ◽  
Shuangjun Xu
Keyword(s):  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Saturated Soil ◽  
Vertical Deformation ◽  
Engineering Project ◽  
Initial Displacement ◽  
Tunnel Excavation ◽  
The Road ◽  
Side Friction

Abstract In order to study the shield construction under an existing highway, the initial displacement and the excess pore water pressure solution from Biot consolidation equation were used to derive the analytical solutions of the vertical deformation and pore water pressure of saturated soil caused by the frontal friction and side friction of the cutterhead. In addition, by introducing the layered method and combining it with other theoretical analytical equations, the expressions of total vertical deformation and total pore water pressure caused by tunnel excavation with different overlying materials were obtained. The simulation results on an engineering project showed that the angle α between the direction of the road and the propulsion axis of the shield had a significant influence on the surface settlement of the road. When the angle α was increased, the settlement curve had higher variation; but the variation would not exceed the maximum settlement value above the shield axis. When the road was perpendicular to the shield axis, a critical point of the road bulging and settlement was formed above the incision. Due to the grinding resistance of the cutterhead, the pore water pressure under the roadbed was distributed asymmetrically on both sides of the shield axis.

TIME TO THE END OF PRIMARY CONSOLIDATION (EOP) OF SOFT CLAYEY SOILS: CONCERNING THE EFFECT OF ATTERBERG’S LIMIT AND CYCLIC LOADING HISTORY

2019 ◽  
Vol 128 (2B) ◽  
pp. 29-41
Author(s):  
Trần Thanh Nhàn
Keyword(s):  
Cyclic Loading ◽  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Clayey Soils ◽  
Loading History ◽  
Cyclic Shear ◽  
Wide Range ◽  
Primary Consolidation ◽  
Time Required

In order to observe the end of primary consolidation (EOP) of cohesive soils with and without subjecting to cyclic loading, reconstituted specimens of clayey soils at various Atterberg’s limits were used for oedometer test at different loading increments and undrained cyclic shear test followed by drainage with various cyclic shear directions and a wide range of shear strain amplitudes. The pore water pressure and settlement of the soils were measured with time and the time to EOP was then determined by different methods. It is shown from observed results that the time to EOP determined by 3-t method agrees well with the time required for full dissipation of the pore water pressure and being considerably larger than those determined by Log Time method. These observations were then further evaluated in connection with effects of the Atterberg’s limit and the cyclic loading history.

Conjectures, Hypotheses, and Theories of Drumlin Formation (In memory of Stanislaw Baranowski)

1981 ◽  
Vol 27 (97) ◽  
pp. 503-505 ◽  
Author(s):  
Ian J. Smalley
Keyword(s):  
Shear Strength ◽  
Pore Water ◽  
Stress Level ◽  
Critical Stress ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Glacial Till ◽  
Forming Process ◽  
Stress Levels

AbstractRecent investigations have shown that various factors may affect the shear strength of glacial till and that these factors may be involved in the drumlin-forming process. The presence of frozen till in the deforming zone, variation in pore-water pressure in the till, and the occurrence of random patches of dense stony-till texture have been considered. The occurrence of dense stony till may relate to the dilatancy hypothesis and can be considered a likely drumlin-forming factor within the region of critical stress levels. The up-glacier stress level now appears to be the more important, and to provide a sharper division between drumlin-forming and non-drumlin-forming conditions.

Sign in / Sign up

Export Citation Format

Share Document