scholarly journals The influence of temperature on earth pressure cell readings

2004 ◽  
Vol 41 (3) ◽  
pp. 551-559 ◽  
Author(s):  
Lyne Daigle ◽  
Jack Q Zhao
Keyword(s):  
Temperature Effect ◽  
Applied Pressure ◽  
Earth Pressure ◽  
Temperature Calibration ◽  
Soil Pressure ◽  
Buried Structures ◽  
Pressure Cell ◽  
Linear Correction ◽  
Influence Of Temperature On ◽  
Measure Soil Pressure

Vibrating-wire earth pressure cells are often used to measure soil pressure in fills and embankments or contact pressure between soil and buried structures. Instrumentation companies provide each cell with a formula to calculate pressure based on frequency and temperature readings. This paper presents the calibration work that was carried out on a series of 76 mm diameter cells and four 228 mm diameter cells with temperatures ranging from –10 to +30 °C with and without the effect of applied pressure. Based on this work and additional data from two field sites, it was found that temperature calibration factors given on the calibration sheet specific to each cell largely underestimated the temperature effect. It was also found that the correction factors were dependent not only on temperature, but also on the pressure applied to the cell. The temperature calibration factor, which is given as a linear correction on the calibration datasheet, becomes parabolic as a pressure is applied on the cell. Based on the findings, recommendations are provided for minimizing the temperature effect on pressure cell readings and improving the accuracy of the temperature calibration factor.Key words: earth pressure cells, soil pressure, temperature calibration, instrumentation.

Analysis of the Interaction of Foundation Pit Supporting Structure and Soil

2014 ◽  
Vol 580-583 ◽  
pp. 401-404
Author(s):  
Yu Qin Feng ◽  
Chen Xi Liu
Keyword(s):  
Soft Soil ◽  
Earth Pressure ◽  
Large Area ◽  
Soil Pressure ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Deep Foundation Pit ◽  
Supporting Structure ◽  
Distribution Mode ◽  
Measure Soil Pressure

This paper analyzes an engineering in an area of China which was processed by vacuum preloading technology in the silt soft soil. This engineering was used rigid supporting structure technology of piles in row and bolts for large area of deep foundation pit supporting. It compared the realistic measure soil pressure and theoretical concluded soil pressure, and got the soil pressure distribution mode which is suitable for silt soft soil processed in this way. The conclusion can provide a reference for similar supporting structure system to calculate earth pressure.

scholarly journals Monitoring a 28.5 m High Anchored Pile Wall in Gravel Using Various Methods

Sensors ◽  
2019 ◽  
Vol 20 (1) ◽  
pp. 80 ◽  
Author(s):  
Ricardo Moffat ◽  
Pablo Parra ◽  
Miguel Carrasco
Keyword(s):  
Optical Fiber ◽  
Earth Pressure ◽  
Time Domain Reflectometry ◽  
Body Motion ◽  
Soil Pressure ◽  
Optical Time Domain Reflectometry ◽  
Excavation Process ◽  
Topographic Survey ◽  
Optical Time ◽  
Horizontal Displacements

Horizontal displacements of a multiple-anchor pile wall in a 28.5 m deep excavation using the top–down construction method have been monitored using optical fiber (Brillouin optical time-domain reflectometry (BOTDR)), strain gauges, inclinometers, and a topographic survey. This work presents a comparison between these different techniques to measure horizontal displacements in the pile at several stages of the soil excavation process. It was observed that displacements can be separated into two components: Rigid body motion and pile flexural deformation. Measurements using optical fiber and inclinometers are considered the most adequate and easy to install. A numerical model allows us to evaluate the influence of earth pressure on the estimated horizontal displacements. It is shown that using soil pressure on the wall given by p = 0.65Kaγh, on a simplified modeled wall, provides a close deduction of horizontal displacements compared to observed values on the field.

Study on Soil Pressure of High Fill Retaining Wall in Construction Stage

2012 ◽  
Vol 204-208 ◽  
pp. 718-721 ◽  
Author(s):  
Peng Li ◽  
Xiao Song
Keyword(s):  
Retaining Wall ◽  
Earth Pressure ◽  
Monitoring Data ◽  
Experiment Study ◽  
Pressure Monitoring ◽  
Soil Pressure ◽  
Construction Stage ◽  
The Earth ◽  
Pressure Calculation ◽  
Practical Guidance

The traditional formula using for the calculation of Expressway on high embankment of the retaining wall and the earth pressure can not be very good practical. In order to accurately determine the soil pressure calculation of the complex retaining wall in construction stage for guaranteeing the engineering safety, the experiment study on soil pressure is done, and the study on soil pressure monitoring data is also done. Then the valuable conclusions are obtained to facilitate better practical guidance for construction.

Evaluation of induced trench twin culverts constructed in deep fill

2020 ◽  
Vol 57 (9) ◽  
pp. 1388-1403
Author(s):  
Campbell Bryden ◽  
Kaveh Arjomandi ◽  
Arun Valsangkar
Keyword(s):  
Experimental Data ◽  
Reinforced Concrete ◽  
Data Acquisition ◽  
Earth Pressure ◽  
Field Studies ◽  
Construction Method ◽  
Recent Criticism ◽  
Soil Pressure ◽  
Earth Pressures ◽  
Overburden Soil

When culverts are installed beneath high embankments, earth loads become excessive and the induced trench construction method is a viable design option to reduce the culvert loads to acceptable levels. However, limited field studies evaluating the performance of induced trench twin culverts are reported in the literature and the practicality and effectiveness of the induced trench construction method (in general) has been subject to recent criticism. This paper describes the performance of twin 3048 mm inside-diameter reinforced concrete culverts constructed with an induced trench beneath 15.3 m of fill. Research instruments and autonomous data acquisition systems were installed during construction to monitor (i) culvert earth pressures, (ii) embankment deformations, and (iii) groundwater elevations in the vicinity of the compressible fill. The experimental observations recorded throughout the construction phase are presented herein; the embankment deformations are indicative of effective positive arching within the induced trench region, and the average earth pressure at the culvert crown was reduced to approximately 48% of the overburden soil pressure. The experimental data are compared with those reported in the literature by others, and the conclusions attained from this study demonstrate the effectiveness of the induced trench construction method.

DESCRIPTION OF A PRESSURE CELL FOR THE MEASUREMENT OF EARTH PRESSURE

1939 ◽  
Vol 17a (11) ◽  
pp. 216-220 ◽  
Author(s):  
I. F. Morrison ◽  
W. E. Cornish
Keyword(s):  
Earth Pressure ◽  
Vibrating Wire ◽  
Electrical Circuits ◽  
Pressure Cell ◽  
Wire Method

The vibrating wire method for measuring strains is used to determine the pressure applied to an earth pressure cell. The construction of the cell, the principle on which it acts, and electrical circuits are described.

Soil Arching over Deeply Buried Thermoplastic Pipe

2003 ◽  
Vol 1849 (1) ◽  
pp. 109-123 ◽  
Author(s):  
Shad M. Sargand ◽  
Teruhisa Masada
Keyword(s):  
Strain Gauge ◽  
Bending Stiffness ◽  
Field Soil ◽  
Stiffness Parameter ◽  
Soil Pressure ◽  
Buried Pipe ◽  
Soil Arching ◽  
Pressure Cell

Soil arching associated with buried thermoplastic pipe is discussed. First, the soil arching phenomenon is described. Then two different approaches are mentioned from the literature to represent the degree of soil arching (or vertical arching factor). The elastic solutions of Burns and Richard are revisited to derive expressions for the vertical soil arching factor for buried pipe. Comparison of the elastic solutions and field soil pressure cell readings reveals the importance of incorporating a bending stiffness parameter. With this finding, the AASHTO method for calculating the load on buried pipe is evaluated against the elastic solutions. The analysis reveals that the AASHTO method is conservative, overestimating the load on thermoplastic pipe by up to 30%. Further evidence to support the finding is found within the strain gauge readings taken on the pipe walls in the field. Therefore, alternative equations derived directly from the elastic solutions are recommended to predict the load on buried thermoplastic pipe instead of the AASHTO method.

Analytical solution for active pressure of narrow backfills considering arching effect

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sahar Ghobadi ◽  
Hadi Shahir
Keyword(s):  
Analytical Solution ◽  
Retaining Wall ◽  
Earth Pressure ◽  
Back Surface ◽  
Active Earth Pressure ◽  
Soil Pressure ◽  
Principal Stresses ◽  
Content Type ◽  
Arching Effect ◽  
Lateral Earth Pressure

Purpose The purpose of this paper is to study the distribution of active earth pressure in retaining walls with narrow cohesion less backfill considering arching effects. Design/methodology/approach To this end, the approach of principal stresses rotation was used to consider the arching effects. Findings According to the presented formulation, the active soil pressure distribution is nonlinear with zero value at the wall base. The proposed formulation implies that by increasing the frictional forces at both sides of the backfill, the arching effect is increased and so, the lateral earth pressure on the retaining wall is decreased. Also, by narrowing the backfill space, the lateral earth pressure is extremely decreased. Originality/value A comprehensive analytical solution for the active earth pressure of narrow backfills is presented, such that the effects of the surcharge and the characteristics of the stable back surface are considered. The magnitude and height of the application of lateral active force are also derived.

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