Comparison of field consolidation with laboratory and in situ tests

1991 ◽  
Vol 28 (1) ◽  
pp. 103-112 ◽  
Author(s):  
C.B. Crawford ◽  
R. G. Campanella
Keyword(s):  
Pore Water Pressure ◽  
Water Pressure ◽  
In Situ Tests ◽  
Constrained Modulus ◽  
Earth Embankment ◽  
Fraser River Delta ◽  
Actual Settlement ◽  
Delta Sediments ◽  
Good Agreement

Settlement calculations for an earth embankment resting on soft, compressible Fraser River Delta sediments were made from laboratory consolidation tests and in situ tests using a piezocone and a flat dilatometer. The calculated values were compared with measured settlements. There was rather good agreement among the three methods of calculation, but the actual settlement was about 60% greater than the average calculated value. Calculated rates of settlement are also compared with observed values. Key words: consolidation, settlements, piezocone, dilatometer, in situ tests, constrained modulus, pore-water pressure, settlement rate.

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.

Numerical Simulation of Storage Tank Foundation Treated by Water Filling Preloading Method

2012 ◽  
Vol 204-208 ◽  
pp. 250-254
Author(s):  
Yan Mei Zhang ◽  
Xu Dong Zhang
Keyword(s):  
Common Ground ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Treatment Method ◽  
Soil Parameters ◽  
Three Dimension ◽  
Time Curve ◽  
Constrained Modulus ◽  
Water Filling ◽  
Preloading Method

The water filling preloading method is the common ground treatment method adopted to reinforce soft tank foundation. The influence laws of load speed, soil parameters on the reinforced effect of soft tank foundation were analyzed by the three-dimension finite element numerical analysis procedure. The research shows that the fovea deformation of single tank bottom under preload is similar to the pan bottom shape; the influence of soil constrained modulus on settlement is remarkable and it also affects the settlement time curve shape; when the constrained modulus is constant, with the permeability coefficient decreasing, the surface doming phenomenon around the tank foundation increases, and the range of upheaval is related to constrained modulus; the influence of loading function on the final settlement is very small, but the influence on pore water pressure is remarkable.

A Heating Experiment in the Argillites in the Meuse/Haute-Marne Underground Research Laboratory

2007 ◽  
Author(s):  
Yannick Wileveau ◽  
Kun Su ◽  
Mehdi Ghoreychi
Keyword(s):  
Research Laboratory ◽  
Linear Thermal Expansion Coefficient ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Linear Thermal Expansion ◽  
General Description ◽  
In Situ Experiment ◽  
Heating And Cooling ◽  
Underground Research Laboratory

A heating experiment named TER is being conducted with the objectives to identify the thermal properties, as well as to enhance the knowledge on THM processes in the Callovo-Oxfordian clay at the Meuse/Haute Marne Underground Research Laboratory (France). The in situ experiment has being switched on from early 2006. The heater, 3 m length, is designed to inject the power in the undisturbed zone at 6 m from the gallery wall. A heater packer is inflated in a metallic tubing. During the experiment, numerous sensors are emplaced in the surrounding rock and are experienced to monitor the evolution in temperature, pore-water pressure and deformation. The models and numerical codes applied should be validated by comparing the modeling results with the measurements. In parallel, some lab testing have been achieved in order to compare the results given with two different scales (cm up to meter scale). In this paper, we present a general description of the TER experiment with installation of the heater equipment and the surrounding instrumentation. Details of the in situ measurements of temperature, pore-pressure and strain evolutions are given for the several heating and cooling phases. The thermal conductivity and some predominant parameters in THM processes (as linear thermal expansion coefficient and permeability) will be discussed.

In Situ Study on Soil Disturbance Induced by Shield Tunneling in Tianjin

2013 ◽  
Vol 368-370 ◽  
pp. 1674-1677
Author(s):  
Yong Hua Cao ◽  
Xiao Qiang Kou
Keyword(s):  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Soil Disturbance ◽  
Ground Settlement ◽  
Soil Pressure ◽  
Shield Tunneling ◽  
Tunnel Face ◽  
Tunneling Process

In urban environment, the soil disturbance induced by shield tunneling can be sensitive because it can cause deformation of the ground and damage the near structure. To study this disturbance in the construction process of Tianjin metro line No.3, in-situ monitoring of pore water pressure, soil pressure and ground settlement were conducted. The pore water pressure was monitored for the soil around the tunnel. The soil pressure was monitored for the soil around the tunnel and on the tunnel face. It was revealed that the pore water pressure and soil pressure changed twice in the tunneling process and these changes were induced by cutting face and grouting at the shield tail. The soil pressure on the tunnel face reached its maximal value when the distance between the cutting face and the sensor elements was around the diameter of the tunnel. Ground settlement developed in the tunneling process. The shape of ultimate settlement trough is closed to the one obtained by Pecks method.

scholarly journals In situ measurements of till deformation and water pressure

2006 ◽  
Vol 52 (177) ◽  
pp. 175-182 ◽  
Author(s):  
Martin Truffer ◽  
William D. Harrison
Keyword(s):  
Pore Water ◽  
Pressure Transducer ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Spatial Homogeneity ◽  
Early Season ◽  
Surface Motion ◽  
Speed Up ◽  
Tilt Sensor

AbstractA newly developed hammer was used to insert two autonomous probes 0.8 m and 2.1 m into clast-rich subglacial till under Black Rapids Glacier, Alaska, USA. Both probes were instrumented with a dual-axis tilt sensor and a pore-water pressure transducer. The data are compared to a 75 day record of surface velocities. Till deformation at depth was found to be highly seasonal: it is significant during an early-season speed-up event, but during long periods thereafter measured till deformation rates are negligible. Both tilt records show rotation around the probe axis, which indicates a change in tilt direction of about 30°. The tilt records are very similar, suggesting spatial homogeneity on the scale of the probe separation (4 m horizontal and 3.3 m vertical). There is evidence that during much of the year sliding of ice over till or deformation of a thin till layer (<20 cm) accounts for at least two-thirds of total basal motion. Basal motion accounts for 50–70% of the total surface motion. The inferred amount of ice–till sliding is larger than that found at the same location in a previous study, when surface velocities were about 10% lower. We suggest that variations in ice–till coupling account for the observed variations in mean annual speed.

Further Study on the Application of Self-Boring Pressuremeter Test in Clays

2011 ◽  
Vol 243-249 ◽  
pp. 2752-2758
Author(s):  
Quan Cao ◽  
Hong Chen
Keyword(s):  
Experimental Investigation ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Small Strain ◽  
Linear Analysis ◽  
The Self ◽  
Geotechnical Investigation ◽  
Pressuremeter Test ◽  
In Situ Method

The self-boring pressuremeter test has potential advantages over the conventional in situ method in the geotechnical investigation. It not only provides fundamental soil properties for the designer, but also plays more important role in the geotechnical analysis. With help of Cambridge self-boring model pressuremeter tests, some new application are studied in this paper as following: (1) Analysis of stress paths in clays adjacent to the cavity wall during self-boring pressuremeter test; (2) Experimental investigation on stiffness of soils at small strain under non-linear analysis; and (3) Study on magnitude of the changes in pore-water pressure of clays, which will help to enlarge the application of self-boring pressuremeter test in geotechnical engineering.

Research on Application of Seismic Piezocone Penetration Tests in Pile Foundation

2011 ◽  
Vol 368-373 ◽  
pp. 2722-2730
Author(s):  
Quan Cao ◽  
Hong Chen ◽  
Fa Bo Chen
Keyword(s):  
Bearing Capacity ◽  
Pile Foundation ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Single Pile ◽  
In Situ Tests ◽  
Stress Theory ◽  
Theoretical Relationship ◽  
Wide Range ◽  
Penetration Tests

According to the characteristics of installation about the penetrometer of seismic piezocone penetration tests (SCPTu) and the pile, a theoretical relationship between ultimate bearing capacity of single pile, time-effect of shaft bearing capacity of single pile, excess pore water pressure around the pile during pile driven and the data measured from SCPTu is developed based on the cavity expanded theory, the Terzaghi one-dimensional consolidation theory and effective stress theory. The result of field test in KunShan and the calculated result which used the theoretical relationship mentioned above are compared. The results indicate that the analytical solutions agree well with the in-situ tests, which show that the application of seismic piezocone penetration tests have wide range in the pile foundation.

scholarly journals A vacuum-refilled tensiometer for deep monitoring of in-situ pore water pressure

2018 ◽  
Vol 0 (0) ◽  
pp. 0-0
Author(s):  
Hamed Sadeghi ◽  
Abraham C.F. Chiu ◽  
Charles W.W. Ng ◽  
Fardin Jafarzadeh
Keyword(s):  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure
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