Field performance, centrifuge testing, and numerical modelling of an induced trench installation

2008 ◽  
Vol 45 (1) ◽  
pp. 85-101 ◽  
Author(s):  
Rodney P. McAffee ◽  
Arun J. Valsangkar
Keyword(s):  
Numerical Modelling ◽  
Pressure Distribution ◽  
Earth Pressure ◽  
Field Performance ◽  
Overburden Pressure ◽  
Centrifuge Testing ◽  
Geotechnical Centrifuge ◽  
Earth Pressures ◽  
Prototype Structure ◽  
Box Culvert

The field performance of an induced trench installation is compared to the results of centrifuge testing and numerical modelling. The measured vertical pressure at the crown of the pipe in the field ranged from 0.24 to 0.36 times the overburden pressure. The horizontal earth pressures measured in the field at the springline level determined a coefficient of lateral earth pressure between 0.39 and 0.49. The culvert was monitored over a period of 2 years following completion of embankment construction indicating no measurable changes in earth pressures and deformations. A model box culvert simulating the prototype height of soil cover, the pipe width, and the thickness of the compressible layer was tested using a geotechnical centrifuge. The prototype structure was also evaluated using numerical modelling to predict full earth pressure distribution and deformations. A comparison of field data, centrifuge testing, and numerical modelling shows that the Marston–Spangler theory used in designing induced trench culverts is conservative. The theory however, does not address or predict the nonuniform pressures on the top, sides, or bottom of the pipe, and therefore numerical analysis should be used to estimate the complete pressure distribution.

Earth pressures exerted on an induced trench cast-in-place double-cell rectangular box culvert

2012 ◽  
Vol 49 (11) ◽  
pp. 1267-1284 ◽  
Author(s):  
Olajide Samuel Oshati ◽  
Arun J. Valsangkar ◽  
Allison B. Schriver
Keyword(s):  
Earth Pressure ◽  
Test Results ◽  
Overburden Pressure ◽  
Centrifuge Testing ◽  
Geotechnical Centrifuge ◽  
Drag Forces ◽  
Field Instrumentation ◽  
Earth Pressures ◽  
Box Culvert ◽  
Base Contact

Earth pressure data from the field instrumentation of a cast-in-place reinforced rectangular box culvert are presented in this paper. The instrumented culvert is a 2.60 m by 3.60 m double-cell reinforced cast-in-place rectangular box buried under 25.10 m of fill constructed using the induced trench installation (ITI) method. The average earth pressure measured across the roof was 0.42 times the overburden pressure, and an average of 0.52 times the overburden pressure was measured at mid-height of the culvert on the sidewalls. Base contact pressure under the rectangular box culvert was also measured, providing field-based data demonstrating increased base pressure resulting from downward drag forces developed along the sidewalls of the box culvert. An average increase of 25% from the measured vertical earth pressures on the roof plus the culvert dead load (DL) pressure was calculated at the culvert base. A model culvert was also tested in a geotechnical centrifuge to obtain data on earth pressures at the top, sides, and base of the culvert. The data from the centrifuge testing were compared with the prototype structure, and the centrifuge test results agreed closely with the measured field prototype pressures, in spite of the fact that full similitude was not attempted in centrifuge testing.

Field Performance and Analysis of 3-m-Diameter Induced Trench Culvert under a 19.4-m Soil Cover

2008 ◽  
Vol 2045 (1) ◽  
pp. 68-76 ◽  
Author(s):  
Bethanie A. Parker ◽  
Rodney P. McAffee ◽  
Arun J. Valsangkar
Keyword(s):  
Pressure Distribution ◽  
Earth Pressure ◽  
Field Performance ◽  
Overburden Pressure ◽  
Vertical Pressure ◽  
Earth Pressures ◽  
Design Loads ◽  
Horizontal Pressure ◽  
Two Stages

An induced trench installation was instrumented to monitor earth pressures and settlements during construction. Some of the unique features of this case study are as follows: (a) both contact and earth pressure cells were used; (b) part of the culvert is under a new embankment and part was installed in a wide trench within an existing embankment; (c) a large stockpile was temporarily placed over the induced trench; and (d) the compressible material was placed in two stages. The maximum vertical pressure measured in the field at the crown of the culvert was 0.24 times the overburden pressure. The maximum horizontal pressure measured on the side of the culvert at the springline was 0.45 times the overburden pressure. The column of soil directly above the compressible zone settled approximately 40% more than did the adjacent fill. The field results at the crown and springline compared reasonably with those observed with numerical modeling. However, the overall pressure distribution on the pipe was expected to be nonuniform, the average vertical pressure calculated by using numerical analysis on top of the culvert over its full width was 0.61 times the overburden pressure, and the average horizontal pressure calculated on the side of the culvert over its full height was 0.44 times the overburden pressure. When the full pressure distribution on the pipe is considered, the recommended design loads from the Marston–Spangler theory slightly underpredict the maximum loads, and the vertical loads control the design.

Centrifuge testing and numerical analysis of box culverts installed in induced trenches

2010 ◽  
Vol 47 (2) ◽  
pp. 147-163 ◽  
Author(s):  
Benjamin L. McGuigan ◽  
Arun J. Valsangkar
Keyword(s):  
Soil Structure ◽  
Earth Pressure ◽  
Centrifuge Testing ◽  
Centrifuge Tests ◽  
Earth Pressures ◽  
Box Culverts ◽  
Box Culvert ◽  
Contact Pressures ◽  
Base Contact ◽  
Good Agreement

Induced trench construction is routinely used for circular conduits, but its application for box culverts is less common. To understand the complex soil–structure interaction issues related to the design of induced trench box culverts, centrifuge tests were performed to measure earth pressures on a model box culvert installed in several induced trench configurations. These tests were modelled with FLAC and good agreement was achieved. A parametric study performed with FLAC identified a preferred compressible zone geometry having a width of 1.2 times the culvert width and a thickness of 0.5 times the culvert height. For this geometry, the earth pressure on the top was 0.28 times the overburden, the lateral earth pressure on the sides was 0.47 times the mid-height overburden, and the contact pressure at the base was 0.73 times the overburden plus the pressure from the dead load of the culvert. The average base contact pressures for the induced trench geometry were 35% lower than those for the corresponding positive projecting case. The induced trench method, therefore, appears to be a viable option for box culverts installed under high embankments.

scholarly journals Post-construction performance of induced trench rigid culverts

2016 ◽  
Vol 53 (11) ◽  
pp. 1807-1821 ◽  
Author(s):  
Benjamin L. McGuigan ◽  
Olajide Samuel Oshati ◽  
Bethanie A. Parker ◽  
Arun J. Valsangkar
Keyword(s):  
New Brunswick ◽  
Case Studies ◽  
Earth Pressure ◽  
Pressure Measurements ◽  
Indirect Assessment ◽  
Earth Pressures ◽  
Box Culverts ◽  
First Results ◽  
Box Culvert ◽  
Satisfactory Manner

Induced trench construction is commonly used to reduce earth pressures on rigid circular and box culverts. Most of the reported literature pertains to the performance of induced trench culverts during construction and shortly after construction. This paper addresses the post-construction performance of induced trench culverts. First, results of field inspection reports are presented as an indirect assessment of performance of 90 induced trench culverts installed in New Brunswick that have been in service for up to 24 years. Second, earth pressure measurements are presented from three case studies where prototype installations were monitored over periods ranging from 4 to 9 years. The case studies presented include a single circular culvert, a cast-in-place double-cell box culvert, and a twin circular culvert installation. The fill heights above the instrumented structures varied from 19 to 25 m. All the available data from both the field inspections and earth pressure measurements indicate that the culverts installed in induced trenches are performing in a satisfactory manner.

scholarly journals Analysis of Vertical Earth Pressure Acting on Box Culverts through Centrifuge Model Test

2021 ◽  
Vol 12 (1) ◽  
pp. 81
Author(s):  
Inyeop Chu ◽  
Sang-Kyun Woo ◽  
Sang Inn Woo ◽  
Joonyoung Kim ◽  
Kicheol Lee
Keyword(s):  
Model Test ◽  
Earth Pressure ◽  
Centrifuge Model Test ◽  
Gravitational Acceleration ◽  
Soil Pressure ◽  
Geotechnical Centrifuge ◽  
Centrifuge Model ◽  
Cover Depth ◽  
Box Culvert ◽  
Vertical Earth Pressure

Due to the lack of surface space, most structures are heading underground. The box culvert is underground infrastructure and serves to protect the buried structure from the underground environments, but it has a different characteristic from other structures in that the inner space is empty. Therefore, in this study, the vertical earth pressure which is the most significant effective stress acting on a box culvert was measured by conducting a geotechnical centrifuge model test. A box culvert was installed following the embankment installation method, and the vertical earth pressure acting on it was measured considering the cover depth, gravitational acceleration, and loading and unloading conditions. The soil pressure measured was greater than the existing theoretical value under high cover depth and the unloading condition, which is considered as the variability of many soils or the residual stress acting under the loading condition. Finally, a goodness-of-fit test was conducted as a part of variability analysis. The measured earth pressure was found to be considerably larger than the existing theoretical value, and the variability was large as well. This means the existing theoretical equation is under-designed, which should be reflected in future designs.

Evaluation of Earth Pressures Against Rigid Retaining Structures with RTT Mode

2010 ◽  
Vol 168-170 ◽  
pp. 200-205
Author(s):  
Fei Song ◽  
Jian Min Zhang ◽  
Lu Yu Zhang
Keyword(s):  
Pressure Distribution ◽  
Formation Mechanism ◽  
Retaining Wall ◽  
Experimental Studies ◽  
Earth Pressure ◽  
Retaining Walls ◽  
Wall Displacement ◽  
The Earth ◽  
Earth Pressures ◽  
Mode A

The evaluation of earth pressure is of vital importance for the design of various retaining walls and infrastructures. Experimental studies show that earth pressures are closely related to the mode and amount of wall displacement. In this paper, based on the reveal of the formation mechanism of earth pressures against rigid retaining wall with RTT mode, a new method is proposed to calculate the earth pressure distribution in such conditions. Finally, the effectiveness of the method is confirmed by the experimental results.

Analysis and Performance of a Braced Cut in Sand with Large Deformations

1972 ◽  
Vol 9 (4) ◽  
pp. 384-406 ◽  
Author(s):  
J. D. Scott ◽  
N. E. Wilson ◽  
Gunther E. Bauer
Keyword(s):  
Experimental Data ◽  
Pressure Distribution ◽  
Earth Pressure ◽  
Water Levels ◽  
Active Earth Pressure ◽  
Actual Distribution ◽  
Dense Sand ◽  
The North ◽  
The Earth ◽  
Earth Pressures

The paper is divided into two parts. The first part deals with the systematic program of measurements undertaken on an open braced cut in dense sand at the Greenway Pollution Control Centre in London, Ontario. In the second part, the experimental data are analyzed and a new solution is presented based on Dubrova's analysis, which related qualitatively and quantitatively the active earth pressure distribution to the mode of deformation of a retaining structure.The roughly L-shaped excavation measured 68 × 42 ft (20.7 × 12.8 m) for the longest leg, the other leg was 30 × 23 ft (9.1 × 7.0 m). The temporary bracing system consisted of interlocking steel sheet piles (Larssen IIIN), and wales and struts from wide-flanged steel sections. The maximum depth of the cut was 50 ft (15.2 m) below ground elevation of 722 ft (220.1 m). The soil consisted of fine uniform dense sand having a relative density varying from medium to very dense. The natural water level was approximately 20 ft (6.1 m) below the ground surface prior to construction.The instrumentation program was carried out during the 6-month construction period (January–June 1964) and consisted of measuring: (1) The strut loads with a mechanical strain indicator (Whitmore gauge) over 8 in. (20.3 cm) gauge lengths, (2) The deformation of the north wall in a horizontal and a vertical plane, (3) The water levels and water pressures from borehole and standpipe observations, and (4) The active and passive earth pressures over the cut with 'Geonor vibrating-wire pressure transducers mounted flush on two adjacent sheet piles of the north wall.Field and laboratory tests supplied the necessary soil data.Comprehensive measurements of this kind in deep cuts in sand, prior to this London investigation, had only been made in Berlin, Munich, and New York. But at London, for the first time the actual distribution of earth pressures in sand were measured on a full-scale braced wall.The analysis of the experimental data showed that the earth pressure distribution can be approximated by the extended Dubrova’s solution. The agreement between the total active earth pressure obtained from the pressure cells and the corresponding Coulomb values varied from excellent (upper bound) to good (lower bound).An experimental relationship between the horizontal soil strain and the variation of K-values over the depth of the cut was established.The different theories for predicting Ko-values do not seem to apply to over consolidated dense sand deposits. The experimental Ko-values, rather, agree with other published experimental values for similar soils.The strut load readings were somewhat erratic, not necessarily corresponding to the excavation progress. The total strut loads were lower than the corresponding forces from the earth pressure cells or the corresponding Coulomb values.

Numerical Simulation on Vertical Earth Pressure Distribution for Culverts under High Fills

2012 ◽  
Vol 204-208 ◽  
pp. 577-580
Author(s):  
He Fan ◽  
Bao Kuan Ning ◽  
Lei Gong
Keyword(s):  
Numerical Simulation ◽  
Stress State ◽  
Pressure Distribution ◽  
Side Wall ◽  
Earth Pressure ◽  
Structure Type ◽  
Mountain Area ◽  
Arch Effect ◽  
Type Selection ◽  
Box Culvert

High fill culverts have been widely used in expressway in mountain area and problems of culverts frequently take place because of improper design including some earth-pressure calculated values conservatively or culvert type selection irrationally. FEM numerical simulation was carried out to investigate the stress state of the culvert fill. The effect of four influences on the stress state of high-filled culvert is discussed. The research results show that culvert structure type influences earth pressure distribution that arch culvert is different to slab and box culvert. Earth pressure values when boundary slope is 1:0.35 are all larger than slope 1:0. Due to arch effect and stress distributed secondly, nonlinear increased amplitude of earth pressure is reduced with fill heightening. Earth pressure of culvert top and side decreased along with culvert side wall thickness increment. The research can give some references on the design correctly.

scholarly journals Centrifuge testing of soil–structure interaction effects on cyclic failure potential of fine-grained soil

2021 ◽  
pp. 875529302098197
Author(s):  
Jason M Buenker ◽  
Scott J Brandenberg ◽  
Jonathan P Stewart
Keyword(s):  
Soil Structure ◽  
Interaction Effects ◽  
Soil Structure Interaction ◽  
Centrifuge Testing ◽  
Geotechnical Centrifuge ◽  
Structure Interaction ◽  
Fine Grained ◽  
Stiffness Properties ◽  
Fine Grained Soil ◽  
Strip Footings

We describe two experiments performed on a 9-m-radius geotechnical centrifuge to evaluate dynamic soil–structure interaction effects on the cyclic failure potential of fine-grained soil. Each experiment incorporated three different structures with a range of mass and stiffness properties. Structures were founded on strip footings embedded in a thin layer of sand overlying lightly overconsolidated low-plasticity fine-grained soil. Shaking was applied to the base of the model container, consisting of scaled versions of recorded earthquake ground motions, sweep motions, and step waves. Data recorded during testing were processed and published on the platform DesignSafe. We describe the model configuration, sensor information, shaking events, and data processing procedures and present selected processed data to illustrate key model responses and to provide a benchmark for data use.

The Challenge of Predicting Field Performance of Air Injection Projects Based on Laboratory and Numerical Modelling

2009 ◽  
Vol 48 (04) ◽  
pp. 23-33 ◽  
Author(s):  
D. Gutierrez ◽  
F. Skoreyko ◽  
R.G. Moore ◽  
S.A. Mehta ◽  
M.G. Ursenbach
Keyword(s):  
Numerical Modelling ◽  
Field Performance ◽  
Air Injection
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