Tunnel flexibility effect on the ground surface acceleration response

2016 ◽  
Vol 15 (3) ◽  
pp. 457-476 ◽  
Author(s):  
Mohammad Hassan Baziar ◽  
Masoud Rabeti Moghadam ◽  
Yun Wook Choo ◽  
Dong-Soo Kim
Keyword(s):  
Ground Surface ◽  
Acceleration Response ◽  
Flexibility Effect

Effects of Underground Structure on Acceleration Response of Site

2011 ◽  
Vol 368-373 ◽  
pp. 2791-2794 ◽  
Author(s):  
Chao Sun ◽  
Qing Wang
Keyword(s):  
Numerical Simulation ◽  
Response Spectrum ◽  
Underground Structure ◽  
Ground Surface ◽  
Acceleration Response ◽  
The Difference ◽  
Peak Value

Through numerical simulation，the article analyzes the difference of ground surface acceleration response under the condition of free site and underground structure. The result shows: compared with free site, the underground structure has a greater influence on the peak value of ground surface acceleration and response spectrum. The paper also presents the influencing regularities.

Large-Scale Two-Dimensional Nonlinear Analysis on Seismic Effect of Fuzhou Basin

2011 ◽  
Vol 90-93 ◽  
pp. 1426-1433 ◽  
Author(s):  
Dan Dan Jin ◽  
Guo Xing Chen ◽  
Fei Fan Dong
Keyword(s):  
Ground Motion ◽  
Large Scale ◽  
Ground Surface ◽  
Response Spectra ◽  
Seismic Effect ◽  
Two Dimensional ◽  
Acceleration Response ◽  
Ground Acceleration ◽  
One Dimensional ◽  
Amplification Effect

So far, nonlinear analyses on seismic effect of large-scale basin model have rarely been reported. Based on the explicit finite element method and 32 CPU parallel computing cluster platform of ABAQUS, a two-dimensional（2D） large-scale refined model for Fuzhou Basin is established using a nonlinear analytical method in the time domain. Both the peak ground acceleration (PGA) and acceleration response spectra of ground surface are emphatically analyzed. Meanwhile, the results by one-dimensional equivalent linearization method in frequency domain are added for the sake of contrast. The study results show that the PGA of ground surface will be obviously amplified when compared with the peak acceleration of bedrock ground motion; and the ground acceleration response spectra of Fuzhou Basin may appear a double-peak or multi-peak phenomenon. Moreover, the 2D large-scale model can reflect amplification effect of Fuzhou Basin soil to bedrock ground motion in particular periods; In addition, the acceleration responses of ground surface right above the bedrock valleys and crests appear larger than the other positions adjacent to them, these phenomenon are generally manifested as focusing effect and amplification effect, which are thought to be produced by the recently deposited soils in the basins as well as the special soil layer such as lens. In general, the PGA of ground surface obtained by 2D model present to be greater than that obtained by the one-dimensional model.

Aplikasi metode tahanan jenis dalam studi geologi karst Gua Seropan di Gunung Kidul, Yogyakarta

2017 ◽  
Vol 12 (2) ◽  
pp. 105-116
Author(s):  
Pulung A. Pranantya ◽  
Nurlia Sadikin
Keyword(s):  
Fresh Water ◽  
Ground Surface ◽  
Water Source ◽  
Raw Water ◽  
Limited Information ◽  
Resistivity Method ◽  
Central Java ◽  
Underground River ◽  
Initial Exploration

In terms of geology, most areas in south of the Gunungkidul District in Central Java consist of the Wonosari formation limestone. The land is generally very dry and source of raw water is also difficult to reach. Findings on the existence of underground river in caves, however, indicate the potential amount of water within the area, especially in the eastern part of the Gunungkidul District. Although limited information available, some fishermen have discovered that Seropan cave contains fresh water source. This cave is situated at 65 m below the cliff. Initial exploration, which done using a multichannel resistivity method, confirmed the availability of freshwater in the cave and underground river. The isopach of cave depth is found in ranges of 80 200 m below the ground surface. The water of Seropan cave can be utilized by implementing pipeline or by drilling at the suggested point based on the interpretation results, i.e. 110o2223.6388 EL 8o42.874 SL. [DY1][PP2][DY1]Perbaiki grammarIn terms of geology, most areas in south of Gunungkidul District in Central Java consist of the Wonosari formation limestone. The land is generally very dry and source of raw water is also difficult to reach. Findings on the exixtence of underground river in caves, however, indicate potential amount of water within the area especially in eastern part of Gunungkidul District. Although limited information available, some fishermans has discovered that Seropan cave contain fresh water source. This cave is situated at 65 m below the cliff. Initial exploration, which done using multichannel resistivity method, confirmed the availability of freshwater in the cave and underground river. The iso pach of cave depth is found in ranges of 80 200 m below the ground surface. The water of Seropan cave can be utilized by implementing pipeline or by drilling at the suggested point based on the interpretation results i.e. 110o2223.6388 EL 8o42.874 SL.[PP2]Sudah diperbaiki

Strretlight pole metal as the medium of Tetragonula sp nest in Indralaya, South Sumatra

2019 ◽  
Vol 1 (2) ◽  
Author(s):  
Hanifa Marisa
Keyword(s):  
Zea Mays ◽  
Air Temperature ◽  
Hevea Brasiliensis ◽  
Citrullus Lanatus ◽  
Ground Surface ◽  
Temperature And Humidity ◽  
Surface Diameter ◽  
Very High

An investigation had been done to Tetragonula (Tetragona) sp nest at Indralaya, South Sumatra to describe the Tetragonula sp nest that use streetlight pole as nest medium during April - May 2019. Purpossive sampling is used to select the target nest. Two streetlight pole found be used by Tetragonula sp as their home. The coordinate of location, heght from ground surface, diameter of streetlight pole, air temperature and humidity, and floral species around nest, were noted. Spot coordinate are S 30 14’ 19.2498’’ and E 1040 39’ 15,3288’’ ; 1,5 m above the ground surface, 12 cm diameter pole, highest air temperature was 35 o C at daylight (April and May 2019), 80 – 90 % humidity at April-May 2019; which Switenia macrophyla, Hevea brasiliensis, Zea mays, and Citrullus lanatus floral species are planted around. Air temperature in the pole is very high, around 40 0 C during daylight.

Development of the mathematical model for assessing the optimal measurement step when surveying the depth of the underground pipeline from the ground

2020 ◽  
Vol 10 (4) ◽  
pp. 364-371
Author(s):  
Ruslan V. Aginey ◽  
◽  
Rustem R. Islamov ◽  
Alexey A. Firstov ◽  
Elmira A. Mamedova ◽  
...  
Keyword(s):  
Mathematical Models ◽  
Survey Data ◽  
Ground Surface ◽  
Maximum Error ◽  
Large Error ◽  
Bending Stress ◽  
Buried Pipeline ◽  
Optimal Measurement ◽  
Pipeline Section ◽  
Bending Stresses

Existing methods for estimating the bending stresses of buried pipeline section based on the survey data for the depth of the axis of the pipeline from the ground surface are characterized by a large error between the real values of the bending stress and the values of the bending stress obtained from the calculation results based on the survey data. The purpose of this study is to improve the methodology for calculating the bending stresses of buried pipeline section based on the results of determining the depth of the axis of the pipeline from the ground surface, taking into account the design features of the pipeline and the used search equipment. Mathematical models are proposed that allow for the set value of the maximum error in determining bending stresses for a particular pipeline to choose the optimal measurement step before the survey, which will allow to reduce the error. Explanations are given on the choice of the maximum step of the study based on the strength characteristics of the pipeline. A calculation is provided that confirms the adequacy of the developed mathematical models and the possibility of their application in practice.

FEATURES OF CONSTRUCTION OF ON-BOARD HELICOPTER RADAR ICE EXPLORATION ON BASIS OF CIRCULAR GROUND SURFACE WITH SYNTHESIS OF APERTURE ROTATING ANTENNA

2019 ◽  
pp. 31-37
Author(s):  
I. G. Antсev ◽  
A. P. Aleshkin ◽  
V. V. Vladimirov ◽  
E. O. Kudrina ◽  
O. L. Polonchik ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Ground Surface ◽  
Rotor Blades ◽  
Navigation Systems ◽  
Propeller Blade ◽  
Antenna Aperture ◽  
Sensing System ◽  
Radar Systems ◽  
Simulation Results ◽  
Circular Antenna Array

The results of modeling the processes of receiving and processing the signals of remote sensing of the Earth’s surface using helicopter radar and synthesizing the antenna aperture due to its placement on the rotating rotor blades are presented. The mathematical correctness of the application of the developed algorithms for processing probing signals, as well as the uniqueness of the measurements, was confirmed. At the same time, the dimensions of the synthesized aperture due to the rotation of the radiator placed at the end of the propeller blade are equivalent to a circular antenna array with a diameter of tens of meters. The functionality of the remote sensing system based on this radar meets the requirements for ice observation and navigation systems for seagoing ships off the coast. The simulation results confirm the promise of further research in this direction and can be used in the development of radar systems with synthesized antenna aperture mounted on rotating rotor blades.

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