scholarly journals Effect of Sheet Pile Driving on Geotechnical Behavior of Adjacent Building in Sand: Numerical Study

2019 ◽  
Vol 5 (8) ◽  
pp. 1726-1737 ◽  
Author(s):  
Ali Basha ◽  
Mohammed Elsiragy
Keyword(s):  
Relative Density ◽  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Pile Driving ◽  
Sheet Pile ◽  
Excess Pore Water Pressure ◽  
Adjacent Structure ◽  
Adjacent Structures ◽  
Excess Pore

Construction vibration such as sheet pile driving can produce earthborn vibrations which may be leads to problems for the supporting soils and adjacent structures. Vibrations create the stress waves traveling outward from the source through the soil and cause structural damage due to dynamic vibration induced settlement. The main aim of the present research is to study the vibration effect through sheet pile driving technique on the surrounding soil and adjacent structure. A series of plain strain finite element analysis using Plaxis 8.2 dynamic module is run to simulate the installation technique of a sheet pile unit using driving technique (hammer type). The effect of construction stages with different embedded sheet pile depth, sand relative density, and foundation distance from the driving source is also studied. The influence of hammer driving amplitude on the foundation response and excess pore water pressure are presented. The results showed that the increase of both embedment sheet pile depth and hammer efficiency can significantly produce higher excess pore water pressure and foundation settlement. The increase of sand density can also has a great effect in increasing the foundation damage of adjacent structure compared with low sand relative density. The building damage can significantly take place when the driving is closed to foundation.

Effect of Relative Density on the Wave-Induced Liquefaction in Seabed Around a Breakwater

2009 ◽  
Author(s):  
Yuichiro Tomi ◽  
Kouki Zen ◽  
Guangqi Chen ◽  
Kiyonobu Kasama ◽  
Yuichi Yahiro
Keyword(s):  
Relative Density ◽  
Pore Water ◽  
Shear Failure ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Ocean Waves ◽  
Excess Pore Water Pressure ◽  
Polymer Fluid ◽  
Wave Induced ◽  
Excess Pore

The liquefaction of seabed induced by ocean waves is considered to be one of the influential phenomena related to damages of coastal marine structures such as the floating of pipelines, the settlement of concrete blocks and the reduction of pile foundation resistance, etc, since the liquefied seabed loses its shear strength and then easily and drastically deforms. A model flume was newly developed to simulate the wave-induced liquefaction in seabed around a breakwater with a reduced model scale against the caisson type breakwater widely used in Japan. The dimension of developed flume was the length of 6.0m, the width of 0.4m and the depth of 0.9m. As for geotechnical parameters affecting the wave-induced liquefaction of seabed around the model breakwater, the effect of seabed density on liquefaction was highlighted in this paper in terms of the generation of pore water pressure in seabed and the settlement of seabed surface. The experiment was carried out under the following conditions; the wave period was 1.0s, the incident wave height was 55mm, the depth of water was 170mm, the thickness of permeable layer was 350mm and the relative density was between 20% and 60%. In order to satisfy similarity law in 1g gravitational field, the polymer fluid was used to decrease the permeability of model seabed. As the result from this study, the following conclusions were obtained; 1) When water was used as a fluid, the liquefaction due to the residual excess pore water pressure happened in the sand bed with the relative density of 23%. However, the liquefaction did not happened in the sand bed with the relative density more than 30%, 2) When the polymer fluid is used for reducing the permeability of model seabed, the generation of pore water pressure ratio becomes larger and the dissipation time of generated pore pressure becomes longer compared with the case using water, 3) When the relative density of seabed was between 20% and 40%, the liquefaction induced by the residual excess pore water pressure was observed in the deep area of model seabed while the shear failure of seabed was observed in the shallow area of model seabed, 4) When the relative density was between 50% and 60%, the liquefaction due to the residual excess pore water pressure was not observed in the present experimental conditions.

Stress–strain pattern–based criterion to assess cyclic shear resistance of soil from laboratory element tests

2016 ◽  
Vol 53 (9) ◽  
pp. 1460-1473 ◽  
Author(s):  
Dharma Wijewickreme ◽  
Achala Soysa
Keyword(s):  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Shear Stiffness ◽  
Large Strains ◽  
Fundamental Parameter ◽  
Stress Strain ◽  
Cyclic Shear ◽  
Excess Pore Water Pressure ◽  
Excess Pore

The cyclic shear response of soils is commonly examined using undrained (or constant-volume) laboratory element tests conducted using triaxial and direct simple shear (DSS) devices. The cyclic resistance ratio (CRR) from these tests is expressed in terms of the number of cycles of loading to reach unacceptable performance that is defined in terms of the attainment of a certain excess pore-water pressure and (or) strain level. While strain accumulation is generally commensurate with excess pore-water pressure, the definition of unacceptable performance in laboratory tests based purely on cyclic strain criteria is not robust. The shear stiffness is a more fundamental parameter in describing engineering performance than the excess pore-water pressure alone or shear strain alone; so far, no criterion has considered shear stiffness to determine CRR. Data from cyclic DSS tests indicate consistent differences inherent in the patterns between the stress–strain loops at initial and later stages of cyclic loading; instead of relatively “smooth” stress–strain loops in the initial parts of loading, nonsmooth changes in incremental stiffness showing “kinks” are notable in the stress–strain loops at large strains. The point of pattern change in a stress–strain loop provides a meaningful basis to determine the CRR (based on unacceptable performance) in cyclic shear tests.

Consolidation Theory for Composite Ground with Granular Columns Based on Different Calculation Models

2011 ◽  
Vol 261-263 ◽  
pp. 1534-1538
Author(s):  
Yu Guo Zhang ◽  
Ya Dong Bian ◽  
Kang He Xie
Keyword(s):  
Pore Water ◽  
Analytical Solutions ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Vertical Flow ◽  
Excess Pore Water Pressure ◽  
Consolidation Theory ◽  
Composite Ground ◽  
Granular Column ◽  
Excess Pore

The consolidation of the composite ground under non-uniformly distributed initial excess pore water pressure along depth was studied in two models which respectively considering both the radial and vertical flows in granular column and the vertical flow only in granular column, and the corresponding analytical solutions of the two models were presented and compared with each other. It shows that the distribution of initial excess pore water pressure has obvious influence on the consolidation of the composite ground with single drainage boundary, and the rate of consolidation considering the radial-vertical flow in granular column is faster than that considering the vertical flow only in granular column.

The Test Study to the Changes of Excess Pore Water Pressure during Precast Pile Construction

2012 ◽  
Vol 193-194 ◽  
pp. 1010-1013
Author(s):  
Shu Qing Zhao
Keyword(s):  
Pore Water ◽  
Clayey Soil ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Excess Pore Pressure ◽  
Soil Pressure ◽  
Excess Pore Water Pressure ◽  
Test Study ◽  
Excess Pore

The construct to precast pile in thick clayey soil can cause the accumulation of excess pore water pressure. The high excess pore pressure can make soil, buildings and pipes surrounded have large deflection, even make them injured. Combining with actual projects, this paper presents an in-situ model test on the changes of excess pore water pressure caused by precast pile construct. It is found that the radius of influence range for single pile driven is about 15m，the excess pore water pressure can reach or even exceed the above effective soil pressure, and there are two relatively stable stages.

A Practical Saturated Sand Elastic-Plastic Dynamic Constitutive Model and Application

2012 ◽  
Vol 446-449 ◽  
pp. 1621-1626 ◽  
Author(s):  
Yan Mei Zhang ◽  
Dong Hua Ruan
Keyword(s):  
Constitutive Model ◽  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Stone Columns ◽  
Saturated Sand ◽  
Multidimensional Model ◽  
Excess Pore Water Pressure ◽  
Elastic Plastic ◽  
Excess Pore

A practical saturated sand elastic-plastic dynamic constitutive model was developed on the base of Handin-Drnevich class nonlinear lag model and multidimensional model. In this model, during the calculation of loading before soil reaches yielding, unloading and inverse loading, corrected Handin-Drnevich equivalent nonlinear model was adopted; after soil yielding, based on the idea of multidimensional model, the composite hardening law which combines isotropy hardening and follow-up hardening, corrected Mohr-Coulomb yielding criterion and correlation flow principle were adopted. A fully coupled three dimension effective stress dynamic analysis procedure was developed on the base of this model. The seismic response of liquefaction foundation reinforced by stone columns was analyzed by the developed procedure. The research shows that with the diameter of stone columns increasing, the excess pore water pressure in soil between piles decreases; with the spacing of columns increasing, the excess pore water pressure increases. The influence of both is major in middle and lower level of composite foundation.

scholarly journals Effect of Reduced Zone on Time-Dependent Analysis of Tunnels

2011 ◽  
Vol 2011 ◽  
pp. 1-12
Author(s):  
Mohammed Y. Fattah ◽  
Kais T. Shlash ◽  
Nahla M. Salim
Keyword(s):  
Finite Element ◽  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Outer Diameter ◽  
Transient Effects ◽  
Excess Pore Water Pressure ◽  
Modified Cam Clay ◽  
Tunnel Diameter ◽  
Excess Pore

The problem of the proposed “Baghdad metro line” which consists of two routes of 32 km long and 36 stations is analyzed. The tunnel is circular in cross-section with a 5.9 m outer diameter. The finite element analyses were carried out using elastic-plastic and modified Cam clay models for the soil. The excavation has been used together with transient effects through a fully coupled Biot formulation. All these models and the excavation technique together with Biot consolidation are implemented into finite-element computer program named “Modf-CRISP” developed for the purpose of these analyses. The results indicate that there is an inward movement at the crown and this movement is restricted to four and half tunnel diameters. A limited movement can be noticed at spring line which reaches 0.05% of tunnel diameter, while there is a heave at the region below the invert, which reaches its maximum value of about 0.14% of the diameter and is also restricted to a region extending to 1.5 diameters. The effect of using reduced zone on excess pore water pressure and surface settlement (vertical and horizontal) was also considered and it was found that the excess pore water pressure increases while the settlement trough becomes deeper and narrower using reduced .

Security Control Method of Loading for Surcharge Preloading Based on the Stress Path

2011 ◽  
Vol 368-373 ◽  
pp. 2795-2803
Author(s):  
Heng Hu ◽  
Yan Li ◽  
Zhi Liang Dong ◽  
Yan Luo ◽  
Gong Xin Zhang
Keyword(s):  
Pore Water ◽  
Safety Factor ◽  
Control Method ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Stress Path ◽  
Excess Pore Water Pressure ◽  
Surcharge Preloading ◽  
Security Control ◽  
Excess Pore

All the time, security control method of loading is an important research part in the surcharge preloading, which is directly related to safety of the construction process. Starting from the stress path, discussing the variation of excess pore water pressure and relationship between stress path and security, and bringing forward the control method with a safety factor Fs based on the stress path. By measuring the change of excess pore water pressure, the control method with a safety factor Fs can reflect quantitatively the security status of soil and achieve the purpose of the process control, finally the security control method including the safety factor of loading and speed control is put forward to monitor construction safety. The safety factor of loading Fs is verified and back analyzed with the finite-element software, getting the correction factor from 0.90 to 1.20.

Sign in / Sign up

Export Citation Format

Share Document