Seismic Performance of Improved Ground Sites during the 2010–2011 Canterbury Earthquake Sequence

2014 ◽  
Vol 30 (1) ◽  
pp. 111-129 ◽  
Author(s):  
Liam M. Wotherspoon ◽  
Rolando P. Orense ◽  
Mike Jacka ◽  
Russell A. Green ◽  
Brady R. Cox ◽  
...  
Keyword(s):  
Large Scale ◽  
Ground Improvement ◽  
Soil Improvement ◽  
Earthquake Sequence ◽  
Soil Conditions ◽  
Ground Failure ◽  
Canterbury Earthquake Sequence ◽  
Liquefaction Assessment ◽  
The City ◽  
Selection Of

The city of Christchurch and the surrounding region on the South Island of New Zealand are underlain by large areas of recent alluvial sediments and fills that are highly susceptible to liquefaction and seismic ground failure. Thus, the widespread liquefaction that occurred following the successive large-scale earth-quakes, with moment magnitudes (MW) ranging from 6.0 to 7.1 that struck the Canterbury region in 2010–2011 was expected. Prior to the series of earthquakes, soil improvement had been used at several sites to mitigate the anticipated damage. This paper reviews the performance of improved sites during the Canterbury earthquake sequence. The existing soil conditions at each site and the design of the ground improvement are discussed, together with descriptions of the post-earthquake damage observed. Moreover, liquefaction assessment within and surrounding a selection of the ground improvement zones is presented.

Some geotechnical aspects of the Hyogo-ken Nanbu (Kobe) earthquake of January 17, 1995

1996 ◽  
Vol 23 (3) ◽  
pp. 778-796 ◽  
Author(s):  
W. D. Liam Finn ◽  
P. M. Byrne ◽  
S. Evans ◽  
T. Law
Keyword(s):  
Soil Structure ◽  
Large Scale ◽  
Ground Improvement ◽  
Lateral Spreading ◽  
Bridge Piers ◽  
Soil Conditions ◽  
Kobe Earthquake ◽  
Port Facilities ◽  
Underground Subway Station ◽  
Directivity Effects

A geological and seismological framework is provided for understanding the damage to structures resulting from soil conditions. The paper focusses on the large-scale failures of the quay walls in Kobe Port due to liquefaction, and contrasts the performance of structures in improved and unimproved ground. Soil–structure interaction problems such as pile foundations, bridge piers, lifelines, and an underground subway station are also described. These failures have important implications for seismic design in the Fraser Delta in British Columbia, which has the potential for extensive liquefaction during a major earthquake. Key words: ground motions, directivity effects, liquefaction, lateral spreading, seismic settlements, seismic damage, port facilities, ground improvement.

Insurance: Its Role in Recovery from the 2010–2011 Canterbury Earthquake Sequence

2014 ◽  
Vol 30 (1) ◽  
pp. 475-491 ◽  
Author(s):  
Andrew King ◽  
David Middleton ◽  
Charlotte Brown ◽  
David Johnston ◽  
Sarb Johal
Keyword(s):  
Flood Risk ◽  
Land Surface ◽  
Earthquake Sequence ◽  
Tectonic Subsidence ◽  
Insurance Claims ◽  
Canterbury Earthquake Sequence ◽  
The City

Earthquakes generate loss only when assets are near enough to be significantly shaken. When communities are highly insured, much of that loss transfers to the insurer. Many events in the 2010–2011 Canterbury Earthquake Sequence were sufficiently shallow and close to (or under) Christchurch to subject the city to very intense shaking (V: 1.7 g; H: 2.2 g). Shaking damage was extensive, exacerbated by the city's setting wherein the eastern suburbs were built on low-lying flatlands (formerly swamp) where liquefaction was widespread, and the southern suburbs, on the flanks of the now-dormant Lyttelton/Akaroa volcano, experienced boulder roll and landslide effects. There were 17 events in the sequence that resulted in insurance claims. The interval between damaging events was insufficient to enable the widespread damage to be assessed or repaired. Furthermore, the combination of tectonic subsidence and liquefaction ejectile lowered the land surface, creating unacceptable flood risk. This paper provides a snapshot of the most complicated insurance settlement program experienced anywhere.

INNOVATIVE SOFT SOIL IMPROVEMENT BY VACUUM DE-WATERING AND DYNAMIC COMPACTION

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Tuncer B. Edil
Keyword(s):  
Large Scale ◽  
Ground Improvement ◽  
Soft Soil ◽  
High Vacuum ◽  
Cohesive Soil ◽  
Soil Improvement ◽  
Economic Benefits ◽  
Dynamic Compaction ◽  
Environmental Benefits ◽  
Improvement Method

Recently, an innovative soft soil improvement method was advanced in China by integrating and modifying vacuum consolidation and dynamic compaction ground improvement techniques in an intelligent and controlled manner. This innovative soft soil improvement method is referred to as “High Vacuum Densification Method (HVDM)” to reflect its combined use of vacuum de-watering and dynamic compaction techniques in cycles. Over the past ten years, this innovative soft soil improvement technique has been successfully used in China and Asia for numerous large-scale soft soil improvement projects, from which enormous time and cost savings have been achieved. In this presentation, the working principles of the HVDM will be described. A discussion of the range of fine-grained, cohesive soil properties that would make them ideal for applying HVDM as an efficient ground improvement method will be discussed. The economic benefits and environmental benefits of HVDM are elucidated.

scholarly journals Feedback of the behaviour of a silo founded on a compressible soil improved by floating stone columns

2018 ◽  
Vol 149 ◽  
pp. 02008
Author(s):  
Ramdane Bahar ◽  
Omar Sadaoui ◽  
Fatma Zohra Yagoub
Keyword(s):  
Soft Soil ◽  
Limit State ◽  
Soil Improvement ◽  
Stone Columns ◽  
Soil Conditions ◽  
Deep Foundations ◽  
The Stability ◽  
Compressible Soil ◽  
The City ◽  
Ongoing Monitoring

The coastal city of Bejaia, located 250 kilometers east of the capital Algiers, Algeria, is characterized by soft soils. The residual grounds encountered on the first 40 meters usually have a low bearing capacity, high compressibility, insufficient strength, and subject to the risk of liquefaction. These unfavorable soil conditions require deep foundations or soil improvement. Since late 1990s, stone columns technique is used to improve the weak soils of the harbor area of the city. A shallow raft foundation on soft soil improved by stone columns was designed for a heavy storage steel silo and two towers. The improvement of 18m depth have not reached the substratum located at 39m depth. The stresses transmitted to the service limit state are variable 73 to 376 kPa. A rigorous and ongoing monitoring of the evolution of loads in the silo and settlements of the soil was carried out during 1400 days that is from the construction of foundations in 2008 to 2012. After the loading of the silo in 2010, settlement occurred affecting the stability of the towers due to excessive differential settlements. Consequently, the towers were inclined and damaged the transporter. This paper presents and discusses the experience feedback of the behavior of these structures. Numerical calculations by finite elements have been carried and the results are compared with the measurements.

Seasonality in Site Response: An Example from Two Historical Earthquakes in Kazakhstan

2019 ◽  
Vol 91 (1) ◽  
pp. 415-426
Author(s):  
Rami Alshembari ◽  
Stefano Parolai ◽  
Tobias Boxberger ◽  
Denis Sandron ◽  
Marco Pilz ◽  
...  
Keyword(s):  
Dynamic Properties ◽  
Site Response ◽  
Noise Analysis ◽  
Soil Layer ◽  
Frozen Soil ◽  
Earthquake Risk ◽  
Soil Conditions ◽  
Soil Parameters ◽  
Ground Failure ◽  
The City

Abstract During the past 150 yr, the city of Almaty (formerly Verny) in Kazakhstan has suffered significant damage due to several large earthquakes. The 9 June 1887 Mw 7.3 Verny earthquake occurred at a time when the city mainly consisted of adobe buildings with a population of 30,000, with it being nearly totally destroyed with 300 deaths. The 3 January 1911 Mw 7.8 Kemin earthquake caused 390 deaths, with 44 in Verny itself. Remarkably, this earthquake, which occurred around 40 km from Verny, caused significant soil deformation and ground failure in the city. A crucial step toward preparing for future events, mitigating against earthquake risk, and defining optimal engineering designs, involves undertaking site response studies. With regard to this, we investigate the possibility that the extreme ground failure observed after the 1911 Kemin earthquake could have been enhanced by the presence of a shallow frozen ground layer that may have inhibited the drainage of pore pressure excess through the surface, therefore inducing liquefaction at depth. We make use of information collected regarding the soil conditions around the city at the time of the earthquakes, the results from seismic noise analysis, borehole data, and surface temperature data. From these datasets, we estimated the necessary parameters for evaluating the dynamic properties of the soil in this area. We successively characterize the corresponding sediment layers at the sites of the observed liquefaction. Although the estimated soil parameters are not optimally constrained, the dynamic analysis, carried out using selected strong‐motion recordings that are expected to be compatible with the two considered events, indicated that the extensive ground failure that occurred during the Kemin event could be due to the presence of a superficial frozen soil layer. Our results indicate that for this region, possible seasonal effects should, therefore, be considered when undertaking site effect studies.

scholarly journals Life Cycle Assessment of Biocemented Sands using Enzyme Induced Carbonate Precipitation (EICP) for Ground Improvement Applications

2021 ◽  
Author(s):  
Emran Alotaibi ◽  
Mohamed Arab ◽  
mohamed Abdallah ◽  
Nadia Nassif ◽  
Maher Omar
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Ground Improvement ◽  
Soil Improvement ◽  
Baseline Scenario ◽  
Carbonate Precipitation ◽  
Global Trend ◽  
Hydrolysis Process ◽  
Hydrolysis Of ◽  
Selection Of

Abstract Integrating sustainability goals into the selection of suitable ground improvement techniques is a global trend. Several bio-inspired and bio-mediated ground improvement techniques have been recently investigated as sustainable alternatives for traditional ground improvement techniques known for their high carbon footprint. Enzyme Induced Carbonate Precipitation (EICP) is an emerging bio-inspired soil improvement technique that is based on the hydrolysis of urea to precipitate carbonates that cement sand particles. Life cycle assessment (LCA) study was conducted to compare the use of traditional ground improvement using Portland cement with bio-cementation via EICP over a range of environmental impacts. The LCA results revealed that EICP soil treatment has nearly 90% less abiotic depletion potential and 3% less global warming potential compared to cement. Compared to cement, EICP has higher acidification and eutrophication potentials due to byproducts during the hydrolysis process. The sensitivity analysis of EICP emissions showed that reducing and controlling the EICP process emissions and using waste non-fate milk has resulted in significantly fewer impacts compared to the EICP baseline scenario.

scholarly journals Probabilistic Method to Assess Model Uncertainty of Rigid Inclusion on a Granular Fill Supporting a Slab Foundation

2020 ◽  
Vol 10 (21) ◽  
pp. 7885 ◽  
Author(s):  
Félix Escolano Sánchez ◽  
Manuel Bueno Aguado ◽  
Eugenio Sanz Pérez
Keyword(s):  
Rigid Inclusion ◽  
Large Scale ◽  
Probabilistic Models ◽  
Probabilistic Method ◽  
Probabilistic Approach ◽  
Soil Improvement ◽  
Soil Conditions ◽  
Soil Mechanic ◽  
Granular Fill ◽  
Slab Foundation

Probabilistic approaches to deal with uncertainty on soil mechanic predictions are on the rise. We developed a procedure to deal with uncertainty coming from soil conditions. It was applied to an analytical model to simulate the behavior of a soil improvement work based on rigid inclusion below a slab foundation. The model can predict the settlements of the slab. Even more, it was also able to provide a confidence level based on a probabilistic approach to the input’s variables. Outputs were compared to large-scale tests. The agreement is outstanding. We try to encourage the use of probabilistic models to solve complex geotechnical problems.

Roman Inscriptions 1995–2000

2003 ◽  
Vol 93 ◽  
pp. 212-294
Author(s):  
Richard Gordon ◽  
Joyce Reynolds
Keyword(s):  
Large Scale ◽  
Recent Progress ◽  
Second Century ◽  
Roman History ◽  
New Work ◽  
Previous Survey ◽  
Set Up ◽  
The City ◽  
Spanish Province ◽  
Selection Of

The intention of this survey, as of its predecessors, is to assess the contribution to Roman studies of recent progress in epigraphy. Its aim is to draw attention to the more important newly-published inscriptions, to known or familiar texts whose significance has been reinterpreted, to the progress of publishing projects, and to a selection of recent work based upon epigraphic sources. It is mainly, but not exclusively, concerned with the implications of new work for Roman history and for that reason does not consider a number of otherwise interesting Hellenistic texts. It hardly needs to be said that there has been no publication remotely as significant as theSC de Cn. Pisone patre, which was reported in the previous survey, and to which we devote some further space here. But there are plenty of new or revised texts of sufficient interest: an honorific decree from Pergamon for a member of the city élite who clearly played a key part in the negotiations with the Romans at the time of the war with Aristonicus; the uncle of Cicero initiated into the Samothracian mysteries in 100B.C.; Octavian honoured at Klaros on account of his ‘quasi-divine exploits’; theTessera Paemeiobrigensisoraes Bergidense, which appears to be an edict by Augustus of 15 B.C. alluding to a hitherto unknown Spanish province of this period — ‘Transduria(na)’; a startling re-interpretation of the significance of the ‘Tiberiéum’ inscription set up by Pontius Pilate at Caesarea Maritima; the splendid replacement for Henzen'sActa Arvalium; the foundation inscription of Sarmizegetusa; one of the very earliest references to waterwheels, calledhydromēchanai(a word unknown to LSJ), in a long-known second-century A.D. text from Macedonia, where they were evidently employed on a large scale to produce income for the city; the transport by ‘barbarians’ of a Roman votive inscription, besides more obviously valuable booty, more than 200 km from the Roman frontier into what is now the Ukraine; and a re-reading suggesting that the well-known ‘milestone’ from Phoenicia honouring Julian astemplorum restauratorwas indeed, as Bowersock argued, erected immediately before the Persian expedition.

Platelet Anti-Aggregating Activity and Tolerance of Clopidogrel in Atherosclerotic Patients

1996 ◽  
Vol 76 (06) ◽  
pp. 0939-0943 ◽  
Author(s):  
B Boneu ◽  
G Destelle ◽  
Keyword(s):  
Platelet Aggregation ◽  
Large Scale ◽  
Bleeding Time ◽  
Antithrombotic Activity ◽  
Ambulatory Patients ◽  
Patients At Risk ◽  
Set Up ◽  
Ischemic Events ◽  
Large Scale Clinical Trial ◽  
Selection Of

SummaryThe anti-aggregating activity of five rising doses of clopidogrel has been compared to that of ticlopidine in atherosclerotic patients. The aim of this study was to determine the dose of clopidogrel which should be tested in a large scale clinical trial of secondary prevention of ischemic events in patients suffering from vascular manifestations of atherosclerosis [CAPRIE (Clopidogrel vs Aspirin in Patients at Risk of Ischemic Events) trial]. A multicenter study involving 9 haematological laboratories and 29 clinical centers was set up. One hundred and fifty ambulatory patients were randomized into one of the seven following groups: clopidogrel at doses of 10, 25, 50,75 or 100 mg OD, ticlopidine 250 mg BID or placebo. ADP and collagen-induced platelet aggregation tests were performed before starting treatment and after 7 and 28 days. Bleeding time was performed on days 0 and 28. Patients were seen on days 0, 7 and 28 to check the clinical and biological tolerability of the treatment. Clopidogrel exerted a dose-related inhibition of ADP-induced platelet aggregation and bleeding time prolongation. In the presence of ADP (5 \lM) this inhibition ranged between 29% and 44% in comparison to pretreatment values. The bleeding times were prolonged by 1.5 to 1.7 times. These effects were non significantly different from those produced by ticlopidine. The clinical tolerability was good or fair in 97.5% of the patients. No haematological adverse events were recorded. These results allowed the selection of 75 mg once a day to evaluate and compare the antithrombotic activity of clopidogrel to that of aspirin in the CAPRIE trial.

A Selection of Bandung City Travel Route Using The FLOYD-WARSHALL Algorithm

2020 ◽  
Vol 12 (7) ◽  
Author(s):  
Muhammad Ghifari Arfananda ◽  
◽  
Surya Michrandi Nasution ◽  
Casi Setianingsih ◽  
◽  
...  
Keyword(s):  
Traffic Congestion ◽  
Rapid Development ◽  
Route Selection ◽  
Tourist Attractions ◽  
Tourist Destinations ◽  
A Value ◽  
Distance Data ◽  
Simple Additive Weighting ◽  
The City ◽  
Selection Of

The rapid development of information and technology, the city of Bandung tourism has also increased. However, tourists who visit the city of Bandung have problems with a limited time when visiting Bandung tourist attractions. Traffic congestion, distance, and the number of tourist destinations are the problems for tourists travel. The optimal route selection is the solution for those problems. Congestion and distance data are processed using the Simple Additive Weighting (SAW) method. Route selection uses the Floyd-Warshall Algorithm. In this study, the selection of the best route gets the smallest weight with a value of 5.127 from the Algorithm process. Based on testing, from two to five tourist attractions get an average calculation time of 3 to 5 seconds. This application is expected to provide optimal solutions for tourists in the selection of tourist travel routes.

Sign in / Sign up

Export Citation Format

Share Document