Significance of In-Situ and Laboratory Tests for Design of Foundations in Granular Carbonate Soils

1991 ◽  
Author(s):  
R.N. Dutt ◽  
W.B. Ingram
Keyword(s):  
Laboratory Tests

scholarly journals Using CPTs to derive thermal properties of soil

2020 ◽  
Vol 205 ◽  
pp. 04005
Author(s):  
Philip J. Vardon ◽  
Joek Peuchen
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Laboratory Tests ◽  
Field Investigation ◽  
Volumetric Heat Capacity ◽  
Cone Penetration ◽  
Cone Penetration Tests ◽  
Penetration Tests ◽  
Properties Of Soil

A method of utilizing cone penetration tests (CPTs) is presented which gives continuous profiles of both the in situ thermal conductivity and volumetric heat capacity, along with the in situ temperature, for the upper tens of meters of the ground. Correlations from standard CPT results (cone resistance, sleeve friction and pore pressure) are utilized for both thermal conductivity and volumetric heat capacity for saturated soil. These, in conjunction with point-wise thermal conductivity and in situ temperature results using a Thermal CPT (T-CPT), allow accurate continuous profiles to be derived. The CPT-based method is shown via a field investigation supported by laboratory tests to give accurate and robust results.

Piezoelectric energy harvesting from roadway deformation under various traffic flow conditions

2020 ◽  
Vol 31 (15) ◽  
pp. 1751-1762
Author(s):  
Yangyang Zhang ◽  
He Zhang ◽  
Chaofeng Lü ◽  
Yisheng Chen ◽  
Ji Wang
Keyword(s):  
Energy Harvesting ◽  
Traffic Flow ◽  
Laboratory Tests ◽  
Piezoelectric Energy Harvesting ◽  
Flow Conditions ◽  
Energy Harvesters ◽  
Piezoelectric Energy ◽  
Roadway Deformation ◽  
Real Traffic

Many laboratory tests and in situ measurements have been conducted to study piezoelectric energy harvesting from roadway deformation. However, the performance of piezoelectric energy harvesters under real traffic flow conditions is still unknown. In this study, an electromechanical model of piezoelectric energy harvesters with detailed parameters (including the geometric parameters, material parameters, and circuits) is established, and the influences of traffic flow conditions (i.e. traffic speed and traffic density) on the output power of piezoelectric energy harvesters are analyzed by employing a scaling law method and traffic flow theory. The results indicate that remarkable differences exist in the load patterns and the frequencies between the laboratory tests (or in situ measurements) and real traffic flow conditions. Because of these differences, the results (especially the output electric power and optimization design methods) of previous studies may be inapplicable for piezoelectric energy harvesters embedded in roadways. Considering the distinguishing features of the traffic load pattern, the optimization criteria to determine the geometric parameters and the intrinsic system parameter of piezoelectric energy harvesters are obtained, and the corresponding optimal output power densities of the piezoelectric energy harvesters are also quantitatively calibrated. These theoretical results may serve as guidelines for optimizing the design of piezoelectric energy harvesters embedded in roadways under different traffic flow conditions.

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