scholarly journals Integrated Geophysical-Geological 3D Model of the Right-Bank Slope Downstream from the Rogun Dam Construction Site, Tajikistan

2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
Hans-Balder Havenith ◽  
Isakbek Torgoev ◽  
Anatoli Ischuk
Keyword(s):  
Layer Thickness ◽  
Mass Movement ◽  
Geophysical Survey ◽  
Slope Instability ◽  
Dam Construction ◽  
Construction Site ◽  
Spectral Ratios ◽  
Soft Layer ◽  
Bank Slope ◽  
The Right

In summer of 2015 we had completed a geophysical survey complemented by borehole drilling near the right-bank slope of the Rogun Dam construction site, Tajikistan. These data were first processed and then compiled within a 3D geomodel. The present paper describes the geophysical results and the 3D geomodel generated for an ancient mass movement located immediately downstream from the construction site. The geophysical survey included electrical and seismic profiles and ambient vibration measurements as well as earthquake recordings. The electrical and seismic data were processed as tomographic sections, the ambient vibrations as horizontal-to-vertical spectral H/V ratios, and the earthquake data mainly in terms of standard spectral ratios. By estimating the average shear wave velocities of the subsurface, we computed the local soft layer thickness from the resonance frequencies revealed by the H/V ratios. Three seismic stations had been installed for ten days along a profile crossing the intermediate plateau. Standard spectral ratios inferred from ten processed earthquake measurements confirmed the presence of a thick soft material layer on the plateau made of weathered rocks, colluvium, and terrace deposits, which produce a medium-level amplification at about 2 Hz. The 3D geomodel was first built on the basis of new topographic data, satellite imagery, and a geological map with two sections. Then, the various electrical resistivity and seismic refraction tomographies were inserted in the geomodel. The soft layer thickness information and borehole data were represented in terms of logs in the model. The site is crossed by the Ionakhsh Fault that could be modeled on the basis of the geological inputs and of a lateral resistivity gradient found on one electrical profile along the steep lower slope. The integrated interpretation of all results reveals that probably only a relatively small part of the ancient giant mass movement is really exposed to slope instability phenomena.

scholarly journals The Soft Layer Thickness Estimation using Microtremor Measurement to Identify Landside Potential in Watukumpul, Central Java, Indonesia.

2021 ◽  
Vol 6 (1) ◽  
pp. 16-23
Author(s):  
Urip Nurwijayanto Prabowo ◽  
Akmal Ferdiyan ◽  
Ayu Fitri Amalia
Keyword(s):  
Layer Thickness ◽  
Spectral Ratio ◽  
Dominant Frequency ◽  
Soil Slope ◽  
Soft Layer ◽  
Thickness Estimation ◽  
Central Java ◽  
Hvsr Method ◽  
Microtremor Measurement ◽  
Potential Area

Watukumpul is an area that is prone to landslides, so determining the soft layer thickness is very important to identify the landslide potential. The soft layer thickness can be estimated using microtremor signal measurements which analyzed using the Horizontal to Vertical Spectral Ratio (HVSR). In this study,we measured microtremor signal of 33location around Watukumpul, Pemalang, Central Java area to determine soft layer thickness. Micretremor signal was analyzed based on theHVSR method using Geopsy software and follow the standard of the Sesame Europan Project. The results of the HVSR method are the HVSR curve that fulfills the reliable curve standard. HVSR curve shows that the dominant frequency of soft layer ranges from 1.36 – 7.62 Hz and the amplification values ranges from 9.00 – 41.45. The soft layer thickness value in the study area ranges from 17.58 - 103.60 meters. The high landslide potential area are located at W7, W8, W18, W30 and W32 where has thin soft layer and high soil slope.

Study on the gallery structure cracking mechanisms and cracking control in dam construction site

2021 ◽  
Vol 121 ◽  
pp. 105135
Author(s):  
Peng Lin ◽  
Zeyu Ning ◽  
Jie Shi ◽  
Chang Liu ◽  
Wenfu Chen ◽  
...  
Keyword(s):  
Dam Construction ◽  
Construction Site ◽  
Cracking Control ◽  
Cracking Mechanisms

scholarly journals ARCHITECTURES OF DEMOCRACY: HOUSING MOVEMENTS AND PROGRESSIVE ARCHITECTS IN SÃO PAULO (1970-1990)

2018 ◽  
Vol 31 (65) ◽  
pp. 369-388 ◽  
Author(s):  
José Henrique Bortoluci
Keyword(s):  
Social Movements ◽  
Political Education ◽  
The Political ◽  
Organizational Practices ◽  
Construction Site ◽  
Urban Social Movements ◽  
Construction Techniques ◽  
The Right ◽  
Political Character ◽  
Design And Construction

Abstract From the late 1970s until the early 1990s, the issue of the right to housing in São Paulo’s peripheral neighborhoods was pursued side by side with a questioning of the political character of design and construction techniques and an attempt to reframe the construction site as a space of cooperation and political education. This article addresses how this articulation between architects and urban social movements led to an innovation of organizational practices within those movements, transformations in the field of architecture, and the local emergence of the idea of the “right to architecture.”

Study the precision of fixed partial dentures of Co-Cr alloys cast over 3D printed prototypes

2018 ◽  
Vol 1 (90) ◽  
pp. 25-32 ◽  
Author(s):  
Ts. Dikova ◽  
Dzh. Dzhendov ◽  
Iv. Katreva ◽  
Ts. Tonchev
Keyword(s):  
Surface Roughness ◽  
Layer Thickness ◽  
Dimensional Accuracy ◽  
Average Roughness ◽  
Dental Clinics ◽  
Primary Model ◽  
3D Printers ◽  
3D Printed ◽  
The Right ◽  
Printed Patterns

Purpose: of this paper is to investigate the accuracy of Co-Cr dental bridges, manufactured using 3D printed cast patterns. Design/methodology/approach: Four-unit dental bridges are fabricated from the alloys i-Alloy and Biosil-f by lost-wax process. The polymeric cast patterns are 3D printed with different layer’s thickness (13 μm, 35 μm and 50 μm). Two 3D printers are used: stereolithographic “Rapidshape D30” and ink-jet “Solidscape 66+”. The geometrical and fitting accuracy as well as the surface roughness are investigated. Findings: It is established that Co-Cr bridges, casted from 3D printed patterns with 50 μm layer thickness, characterize with the largest dimensions – 3.30%-9.14% larger than those of the base model. Decreasing the layer thickness leads to dimensional reduction. The dimensions of the bridges, casted on patterns with 13 μm layer thickness, are 0.17%-2.86% smaller compared to the primary model. The average roughness deviation Ra of the surface of Co-Cr bridges, manufactured using 3D printed patterns, is 3-4 times higher in comparison to the bridge-base model. The greater the layer thickness of the patterns, the higher Ra of the bridges. The silicone replica test shows 0.1-0.2 mm irregular gap between the bridge retainers and abutments of the cast patterns and Co-Cr bridges. Research limitations/implications: Highly precise prosthetic constructions, casted from 3D printed patterns, can be produced only if the specific features of the 3D printed objects are taken in consideration. Practical implications: Present research has shown that the lower the thickness of the printed layer of cast patterns, the higher the dimensional accuracy and the lower the surface roughness. Originality/value: The findings in this study will help specialist in dental clinics and laboratories to choose the right equipment and optimal technological regimes for production of cast patterns with high accuracy and low surface roughness for casting of precise dental constructions.

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