Comparative and Study the Influence of Sand Depth for Liquefied Evaluation

2013 ◽  
Vol 842 ◽  
pp. 733-736
Author(s):  
Zhao Yan Li ◽  
Zhuo Shi Chen
Keyword(s):  
Field Data ◽  
Evaluation Method ◽  
Evaluation Methods ◽  
Critical Curve ◽  
National Standard ◽  
Tangshan Earthquake ◽  
In Situ Test ◽  
Test Technology ◽  
At Home

CPT is a kind of relatively superior field test technology, which is one of important the liquefaction in-situ test at home and abroad. In 1987, China has formed the national standard CPT liquefaction evaluation method, which predominantly from 1976 Tangshan earthquake liquefaction data, and then has not been tested. Recently by the 40 CPT liquefaction field data of Bachu earthquake obtained a liquefied evaluation formula. Due to comparing the liquefied evaluation methods at home and abroad, found the national standard CPT liquefied critical curve is qualitatively distinct to the others liquefied evaluation methods. If it is wrong about the code of CPT liquefied evaluation method, which the liquefied critical curve will be smaller along with the direction of the depth, will direct the liquefied evaluation critically be conservative and the depth liquefaction evaluation clearly be hazardous. In theory, this problem can be attributed to the influence of sand depth for liquefied evaluation, worthy of further discussion.

Preliminary field data of selected deep-rooted vegetation effects on the slope-vegetation-atmosphere interaction: results from an in-situ test 

2021 ◽  
Author(s):  
Vito Tagarelli ◽  
Federica Cotecchia ◽  
Osvaldo Bottiglieri
Keyword(s):  
Soil Water ◽  
Pore Water ◽  
Field Data ◽  
Test Site ◽  
Grass Species ◽  
In Situ Test ◽  
South Eastern ◽  
Atmosphere Interaction ◽  
The Stability

<p>The soil-vegetation-atmosphere interaction is becoming more and more the subject of intense scientific research, motivated by the wish of using smart vegetation implants as sustainable mitigation measure for erosive phenomena and slope instability processes. <br>The use of novel naturalistic interventions making use of vegetation has been already proven to be successful in the reduction of erosion along sloping grounds, or in increasing the stability of the shallow covers of slopes, whereas the success of vegetation as slope stabilization measure still needs to be scientifically proven for slopes location of deep landslides, whose current activity is climate-induced, as frequent in the south-eastern Apennines. Recently, though, peculiar natural perennial grass species, which develop deep root systems, have been found to grow in the semi-arid climate characterizing the south-eastern Apennines and to determine a strong transpirative flow. Therefore, their peculiar leaf architecture, their crop density, combined with their perennial status and transpiration capacity, make such grass species suitable for the reduction of the net infiltration rates, equal to the difference between the rainfall rate and the sum of the runoff plus the evapotranspiration rate. As such, the grass species here of reference have been selected as vegetation measure intended to determine a reduction of the piezometric levels in the slope down to large depths, in order to increase the stability of deep landslide bodies. <br>At this stage, only preliminary field data representing the interaction of clayey soils with the above cited vegetation species are available. These have been logged within a full scale in-situ test site, where the deep-rooted crop spices have been seeded and farmed. The test site (approximatively 2000 m<sup>2</sup>) has been set up in the toe area of the climate-induced Pisciolo landslide, in the eastern sector of the Southern Apennines.<br>The impact of the vegetation on the hydro-mechanical state of the soil is examined in terms of the spatial and temporal variation of the soil water content, suction an pore water pressure from ground level down to depth, both within the vegetated test site and outside it, where only spare wild vegetation occur, in order to assess the effects of the implant of the selected vegetation. The soil water contents, suctions and pore water pressures have been also analyzed taking into account of the climatic actions, monitored by means of a meteorological station. </p>

The Applicability of Existing Typical Liquefaction Evaluation Methods of Site Soils Based on Shear Wave Velocities for Bachu Earthquake

2011 ◽  
Vol 90-93 ◽  
pp. 1412-1418
Author(s):  
Jiang Hua Shi ◽  
Zhen Zhong Cao ◽  
Zhao Yan Li ◽  
Xiao Ming Yuan ◽  
Lin Dong
Keyword(s):  
Shear Wave ◽  
Shear Wave Velocity ◽  
Satisfactory Result ◽  
Evaluation Method ◽  
Evaluation Methods ◽  
Wave Velocities ◽  
Shear Wave Velocities ◽  
Testing Data ◽  
Critical Lines

Based on liquefaction survey of 2003 Xinjiang Bachu earthquake of Ms6.8 and in-situ shear wave velocity testing data, the feasibility and applicability of five typical liquefaction evaluation methods which use shear wave velocities as criteria are presented herein. Analysis showed that none of the five liquefaction evaluation methods can provide a satisfactory result in Bachu area. The successful judging rates are only 36% to 64%. The intensity method which is employed to evaluate liquefied and non-liquefied sites in Bachu area provides only 40% successful judging rate, and the method is risky in intensity VII area and conservative in intensity IX area. The critical lines of the five methods deviate greatly from the actual lines. In intensity VII area all the five methods incorrectly misjudge. Further work has to be conducted to research on the soil properties in Bachu area and to establish the regional liquefaction evaluation method in Xinjiang.

scholarly journals EFFECT OF BLASTING ON THE STABILITY OF LINING DURING EXCAVATION OF NEW TUNNEL NEAR THE EXISTING TUNNEL

2021 ◽  
Vol 30 (1) ◽  
Author(s):  
Tuan Minh Tran ◽  
Quang Huy Nguyen
Keyword(s):  
Field Data ◽  
Damage Zone ◽  
Field Tests ◽  
Surrounding Rock ◽  
In Situ Test ◽  
The Stability ◽  
Relationship Of ◽  
The Impact ◽  
The Relationship

In recent years, experimental and numerical researches on the effect of blasting pressure on the stability of existing tunnels was widely obtained. However, the effect of the blasting pressure during excavation a new tunnel or expansion old tunnels on an existing tunnel has disadvantages and still unclear. Some researches were carried out to study the relationship of the observed Peak Particle Velocity (PPV) on the lining areas along the existing tunnel direction, due to either the lack of in situ test data or the difficulty in conducting field tests, particularly for tunnels that are usually old and vulnerable after several decades of service. This paper introduces using numerical methods with the field data investigations on the effect of the blasting in a new tunnel on the surrounding rock mass and on the existing tunnel. The research results show that not only predicting the tunnel lining damage zone under the impact of blast loads but also determination peak maximum of explosion at the same time at the surface of tunnel working.

Examination of CPT-Based Liquefaction Evaluation Methods for New Zealand Earthquake

2013 ◽  
Vol 477-478 ◽  
pp. 1105-1108
Author(s):  
Tong Zhi Chen ◽  
Xiao Ming Yuan
Keyword(s):  
New Zealand ◽  
Test Data ◽  
Historical Earthquakes ◽  
Evaluation Methods ◽  
Field Investigation ◽  
The Other ◽  
Success Rates ◽  
In Situ Test ◽  
First Time

On February 22, 2011 a MW6.2 earthquake struck Christchurch in New Zealand, which is the first time that liquefaction acts as the main cause of damage since there is survey record of historical earthquakes. On the basis of field investigation and in-situ test data, domestic and foreign liquefaction evaluation methods based on CPT including Chinese code, Robertson and Olsen methods are examined and their applicability and reliability are assessed. Analysis shows that the method adopted in Chinese code is more dangerous, whose success rates of liquefaction and non-liquefaction evaluation are 70% and 94%.The other two methods abroad are severely conservative, for the success rates of liquefaction and non-liquefaction evaluation of Robertson method are 100% and 40%, and Olsen method 100% and 11% respectively. Liquefaction evaluation methods need further research to be improved.

SenCity – Evaluating Users’ Experiences of Intelligent Lighting for Well-Being in Smart Cities

2018 ◽  
pp. 60-67
Author(s):  
Henrika Pihlajaniemi ◽  
Anna Luusua ◽  
Eveliina Juntunen
Keyword(s):  
Case Studies ◽  
Smart City ◽  
Smart Cities ◽  
Well Being ◽  
Evaluation Methods ◽  
Data Analyses ◽  
Sense Of Security ◽  
System Data

This paper presents the evaluation of usersХ experiences in three intelligent lighting pilots in Finland. Two of the case studies are related to the use of intelligent lighting in different kinds of traffic areas, having emphasis on aspects of visibility, traffic and movement safety, and sense of security. The last case study presents a more complex view to the experience of intelligent lighting in smart city contexts. The evaluation methods, tailored to each pilot context, include questionnaires, an urban dashboard, in-situ interviews and observations, evaluation probes, and system data analyses. The applicability of the selected and tested methods is discussed reflecting the process and achieved results.

scholarly journals Research on Strength Test Technology and Fatigue Evaluation Method of Bogie Frame and Body Bolster

2021 ◽  
Vol 1972 (1) ◽  
pp. 012038
Author(s):  
Cao Yu ◽  
Lu Chong ◽  
Li Zihua ◽  
Song Jie ◽  
Ding Xiebin
Keyword(s):  
Evaluation Method ◽  
Strength Test ◽  
Bogie Frame ◽  
Test Technology ◽  
Fatigue Evaluation

scholarly journals Design and Application of an In Situ Test Device for Rheological Characteristic Measurements of Liquefied Submarine Sediments

2021 ◽  
Vol 9 (6) ◽  
pp. 639
Author(s):  
Hong Zhang ◽  
Xiaolei Liu ◽  
Anduo Chen ◽  
Weijia Li ◽  
Yang Lu ◽  
...  
Keyword(s):  
Yellow River ◽  
Rheological Characteristic ◽  
Yellow River Delta ◽  
Turbidity Currents ◽  
Rheological Characteristics ◽  
Submarine Landslides ◽  
Test Device ◽  
Offshore Area ◽  
In Situ Test

Liquefied submarine sediments can easily lead to submarine landslides and turbidity currents, and cause serious damage to offshore engineering facilities. Understanding the rheological characteristics of liquefied sediments is critical for improving our knowledge of the prevention of submarine geo-hazards and the evolution of submarine topography. In this study, an in situ test device was developed to measure the rheological properties of liquefied sediments. The test principle is the shear column theory. The device was tested in the subaqueous Yellow River delta, and the test results indicated that liquefied sediments can be regarded as “non-Newtonian fluids with shear thinning characteristics”. Furthermore, a laboratory rheological test was conducted as a contrast experiment to qualitatively verify the accuracy of the in situ test data. Through the comparison of experiments, it was proved that the use of the in situ device in this paper is suitable and reliable for the measurement of the rheological characteristics of liquefied submarine sediments. Considering the fact that liquefaction may occur in deeper water (>5 m), a work pattern for the device in the offshore area is given. This novel device provides a new way to test the undrained shear strength of liquefied sediments in submarine engineering.

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