Centrifuge modeling of in-situ loading tests using undisturbed scoria samples.

A series of in situ static loading tests of square footing were carried out on the geobelt-reinforced gravel cushion on soft silt. The reinforced gravel cushion was thin with the depth-to-width ratio of 0.2. A parameters study was conducted by considering the number of geobelt layers, the depth of the first geobelt layer beneath the footing, the vertical spacing between two geobelt layers, the linear density of reinforcement, and the material type of geobelt. The pressure distribution on bottom of the cushion was measured. The test results showed that the bearing capacity of reinforced gravel cushion was significantly larger than that of unreinforced gravel cushion, and the stress diffusion effect of reinforced gravel cushion was also more pronounced than that of the unreinforced cushion. The pressure distribution on bottom of reinforced gravel cushion was in a saddle shape. According to calculation and analysis, the stress diffusion angles of reinforced cushions were all larger than 20°.

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Centrifuge Modeling of In situ Surfactant Enhanced Flushing of Diesel Contaminated Soil

Geotechnical Testing Journal ◽

10.1520/gtj103695 ◽

2011 ◽

Vol 34 (6) ◽

pp. 103695 ◽

Cited By ~ 3

Author(s):

L. D. Suits ◽

T. C. Sheahan ◽

Amin Yousefnia Pasha ◽

Liming Hu ◽

Jay N. Meegoda ◽

...

Keyword(s):

Contaminated Soil ◽

Centrifuge Modeling

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NONLINEAR ANALYTICAL MODEL FOR PILED RAFT FOUNDATION SUBJECTED TO HORIZONTAL LOAD AND APPLICATION OF IN-SITU LATERAL LOADING TESTS

Journal of Structural and Construction Engineering (Transactions of AIJ) ◽

10.3130/aijs.70.113_1 ◽

2005 ◽

Vol 70 (589) ◽

pp. 113-119 ◽

Cited By ~ 1

Author(s):

Hiroshi NAGAI ◽

Tsutomu TSUCHIYA

Keyword(s):

Analytical Model ◽

Lateral Loading ◽

Horizontal Load ◽

Piled Raft ◽

Piled Raft Foundation ◽

Raft Foundation ◽

Nonlinear Analytical Model ◽

Loading Tests

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TBS7 Terminology, descriptions and symbols in loading tests in situ of concrete structures

RILEM Technical Recommendations for the testing and use of construction materials ◽

10.1201/9781482271362-267 ◽

1994 ◽

pp. 1103-1106

Keyword(s):

Concrete Structures ◽

Loading Tests

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Centrifuge Modeling and Numerical Simulation of Air Sparging Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.378-379.445 ◽

2011 ◽

Vol 378-379 ◽

pp. 445-448

Author(s):

Li Ming Hu ◽

Heng Zhen Lee ◽

Jian Wang ◽

Jian Ting Du

Keyword(s):

Numerical Simulation ◽

Water Saturation ◽

Cone Angle ◽

Design Tool ◽

Centrifuge Modeling ◽

Air Sparging ◽

Injection Point ◽

Buoyant Force ◽

In Situ Conditions

Air sparging (AS) is one of the in-situ groundwater remediation techniques for remediating volatile organic compounds (VOCs) contaminated soil, and the knowledge of air flow features is essential in designing air sparging system for soil remediation. The centrifuge modeling technique was employed to simulate the in-situ conditions and to investigate air follow characteristics during air sparging by using glass beads as soils. Several centrifugal modeling tests were performed under various g-levels. According to the test results, the zone of influence (ZOI) during air sparging is in a truncated-cone shape under various g-levels, which can be expressed by the lateral expansion around the air injection point and the cone angle between the vertical axis and the boundary of ZOI. A 2D numerical model is used to model the air movement during air sparging process. The ZOI and the water saturation distribution were obtained. The results agree well with the centrifuge test data, which indicates the two phase flow model is reasonable to simulate the air sparging process. It was also shown that air compressibility and buoyant force have a significant influence on the extent of ZOI and should be adequately considered. Hence centrifuge modeling and numerical simulation can be used as a design tool for in-situ air sparging system

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In Situ Assessment Method of Wood Using Normalized Withdrawal Resistances of Metric-Screw Type Probes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.778.217 ◽

2013 ◽

Vol 778 ◽

pp. 217-224 ◽

Cited By ~ 1

Author(s):

Nobuyoshi Yamaguchi

Keyword(s):

Shear Strength ◽

Cross Section ◽

Assessment Method ◽

Strength Distribution ◽

Shear Loading ◽

Resistance Measurement ◽

Strength Based ◽

In Situ Assessment ◽

Loading Tests

Withdrawal resistances of wood have been applied for in situ assessment of wood in existing timber structures. The author had proposed method to estimate shear strengths of wood from measured withdrawal resistances of probes which are screwed into wood. In order to verify the accuracy of these estimated shear strengths by proposed methods, withdrawal resistance measurements and shear loading tests were conducted for wood. Single withdrawal resistance measurement was applied for wood specimens, and estimated shear strengths from withdrawal measurements were compared to the measured shear strengths by shear loading tests of wood. Correlation between the estimated shear strengths and measured shear strengths of specimens was reasonably good (R2=0.73). Multiple coaxial withdrawal resistance measurement which can provide distribution of shear strengths in cross-section of wood was also proposed. The average of estimated shear strengths by single withdrawal resistances was 7 percent less than that of measured shear strengths. The average of estimated shear strength by multiple coaxial withdrawal resistances was 3 percent greater than that of measured shear strengths. The single withdrawal measurements and multiple coaxial withdrawal resistances are available to estimate shear strengths of wood and shear strength distribution in the cross-section of wood. Estimated shear strengths obtained from these methods will be valuable for strength based in situ assessment of wood.

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