Evaluation Of Liquefaction Potential Of An Earth Dam Foundation Using In Situ Tests,
2013
National Agronomic Institute of Tunisia, Tunisia
Evaluation Of Liquefaction Potential Of An Earth Dam Foundation Using In Situ Tests, Ikram Guettaya, Mohamed Ridha El Ouni
International Conference on Case Histories in Geotechnical Engineering
This paper presents a case study of liquefaction potential assessment carried out under an earth dam foundation in Tunisia. An emphasis was made on the exploration of geotechnical conditions and the interpretation of field tests results collected before and after soil densification using the vibrocompaction technique. The assessment of soil liquefaction susceptibility was made using deterministic and probabilistic simplified procedures developed from several case histories. Conclusively, the obtained results show that before vibrocompaction the soil was prone to the liquefaction hazard. However, after vibrocompaction, a significant improvement of the soil resistance reduces the liquefaction potential of the sandy foundation. Indeed, …
Liquefaction Of Mine Tailings,
2013
Southern Illinois University, Carbondale, IL
Liquefaction Of Mine Tailings, Vijay K. Puri, Todd R. Kostecki
International Conference on Case Histories in Geotechnical Engineering
Liquefaction of mine tailings is known to occur during cyclic, quasi-static & static loading cases but is still a relatively misunderstood concept because tailings dam failures continue to occur. In the worst case scenario the results are high costs, hindered public perception, environmental cleanup and worst of all, the loss of life. A better understanding of this issue is essential for any engineer associated with the mining and/or geotechnical industry, and in particular tailings dam construction and maintenance. This paper presents the liquefaction concept, some case histories dealing with failure of mine tailings dams, available testing methods and some dated …
Estimating Seismic Settlements From Liquefaction And Cyclic Softening And Their Impact To Design Of A School Building,
2013
Kleinfelder, Inc., Stockton, CA
Estimating Seismic Settlements From Liquefaction And Cyclic Softening And Their Impact To Design Of A School Building, James Wetenkamp, Jorge Meneses, Zia Zafir
International Conference on Case Histories in Geotechnical Engineering
Estimation of static and seismic settlements is critical for the design of a structure to assess whether the structure can tolerate given levels of total and differential settlements and angular distortion. The design of a public school building required the estimation of both liquefaction-induced settlement due to the presence of a potentially liquefiable layer, and settlement from cyclic softening of soft clay layers. Tolerable levels of differential settlements for the proposed school building were not to exceed 2 inches across the building. The soft clay had a plasticity index of 12, a liquid limit of 32, and SPT blow counts …
Lessons From The Seismic Performance Of Pile-Supported Bridges Affected By Liquefaction During The M8.8 2010 Maule Chile Earthquake,
2013
Pontificia Universidad Católica de Chile, Chile
Lessons From The Seismic Performance Of Pile-Supported Bridges Affected By Liquefaction During The M8.8 2010 Maule Chile Earthquake, Christian Ledezma
International Conference on Case Histories in Geotechnical Engineering
Ground failure case studies have been the source of the most important advances in geotechnical earthquake engineering over the past 50 years. Documented case histories from the 2010 M8.8 Maule Chile earthquake will, if carefully studied, further advance this field. The 2010 M8.8 earthquake in Chile showed that liquefaction-induced soil-foundation-structure interaction problems are still far from being completely understood. The observed damage and partial collapse of pile-supported bridges like Juan Pablo II, Llacolén, Tubul, La Mochita, and Raqui, is most likely due to the effects of liquefaction-induced lateral and vertical ground displacement, which often causes large ground deformations that impose …
Performance Of Lightweight Structures During Liquefaction From Recent Earthquakes,
2013
Kleinfelder Inc., San Diego, CA
Performance Of Lightweight Structures During Liquefaction From Recent Earthquakes, Jorge F. Meneses, Yun Liao
International Conference on Case Histories in Geotechnical Engineering
Several case histories of lightweight structures performance during liquefaction from recent earthquake are reviewed. The review is focused on performance of lightweight structures in terms of liquefaction-induced vertical settlement, tilting, lateral displacement and their effects on occupancy and functionality of the structures. These case histories were reported during the 1997 Mw 7.4 Caucete- Argentina, 2007 Mw 8.0 Pisco-Peru, 2010 Mw 8.8 Chile, 2010 Mw 7.2 El Mayor-Cucapah, 2010-2011 New Zealand, and 2011 Mw 9.0 Great East Japan earthquakes. The review is performed to identify similarities, discuss conditions, and their effects on foundation and structures. Financial …
Seismic Hazard Assessment And Design Ground Motion: Lessons Learned From Recent Earthquakes,
2013
University of Kentucky, Lexington, KY
Seismic Hazard Assessment And Design Ground Motion: Lessons Learned From Recent Earthquakes, Zhenming Wang
International Conference on Case Histories in Geotechnical Engineering
Recent earthquakes, the 2008 Wenchuan, 2009 L’Aquila, 2010 Haiti, and 2011 Christchurch and Japan in particular, have called attention to the probabilistic seismic hazard maps, particularly the ground motions with 10, 5, and 2 percent probabilities of exceedance in 50 years. As discussed in this paper, these ground motions are artifacts because they were produced from probabilistic seismic hazard analysis (PSHA). PSHA is a mathematical formulation derived from a rigorous probability analysis of the distribution of earthquake magnitudes, locations, and ground-motion attenuation. Some of the assumptions and distributions that PSHA is based on have been found to be invalid in …
Spectral Attenuation Characteristics Of Strong Ground Motions In East-Central Iran Using Theoretical Data,
2013
Islamic Azad University, Iran
Spectral Attenuation Characteristics Of Strong Ground Motions In East-Central Iran Using Theoretical Data, Majid Mahood, Hossein Hamzehloo
International Conference on Case Histories in Geotechnical Engineering
Ground-motion prediction equations are an essential element of PSHA. In seismic hazard analysis, attenuation calculations determine how quickly ground motions decrease as the distance from a seismic event increases. The estimation of ground motion for future earthquakes as a function of magnitude and distance is an important problem from earthquake engineering point of view. This article presents spectral equations for the estimation of horizontal strong ground motions caused by shallow crustal earthquakes with magnitude range of Mw 5.0 to 7.4 and distance to the surface projection of the fault less than 100 km for theoretical (simulated) records. The reason …
Variation Of Intrinsic And Scattering Attenuation Of Seismic Waves With Depth In The Bam Region, East-Central Iran,
2013
Islamic Azad University, Iran
Variation Of Intrinsic And Scattering Attenuation Of Seismic Waves With Depth In The Bam Region, East-Central Iran, Majid Mahood
International Conference on Case Histories in Geotechnical Engineering
The attenuation properties of the lithosphere in the Bam region, East-Central Iran, have been investigated. For this purpose, 42 local earthquakes (aftershocks of Bam earthquake, Mw 6.5, 2003) having focal depths less than 25 km have been used. The quality factor of coda waves (Qc) has been estimated using the single backscattering model. The quality factors Qp, Qd (P and direct S-waves) have been estimated using the extended-coda normalization method. Qi and Qs (the intrinsic and scattering attenuation parameters) have been estimated for the region. The values of Qp, Q …
Evaluation Of Site Amplification Of Erbaa, Tokat (Turkey),
2013
Yuzuncu Yil University, Turkey
Evaluation Of Site Amplification Of Erbaa, Tokat (Turkey), Muge K. Akin, Steven L. Kramer, Tamer Topal
International Conference on Case Histories in Geotechnical Engineering
The study area, Erbaa, is one of the largest towns of Tokat with a population of 47000 in the northern part of Turkey. Erbaa is in North Anatolian Fault Zone (NAFZ) and partly located on the Kelkit river plain, also referred to as the Erbaa basin. After the disastrous 1942 earthquake (Ms=7.2), the settlement area was seriously damaged and moved farther southwards of its old place in 1944. Dynamic properties of Erbaa soils were determined and shear wave velocity profiles were prepared to be used in site response analyses as part of a microzonation study. During this process, …
Modified Value Of Rock Quality Designation Index Rqd In Rock Formation,
2013
Housing and Building National Research Center (HBRC), Egypt
Modified Value Of Rock Quality Designation Index Rqd In Rock Formation, Ahmed T. M. Farid
International Conference on Case Histories in Geotechnical Engineering
The rock quality designation, RQD, is a commonly index used in the description of rock mass quality. This RQD, index value is used to predict the engineering properties of the rock strata under study. The RQD index value was introduced for the engineering applications, such as mining and geotechnical engineering. Calculating of RQD index for rock formation is a great part due to its simplicity. However, this also leads to a number of limitations, including among other, a dependency of RQDm value on the borehole orientation and on the selected threshold value for the minimum intact core length. In this …
Influence Of Relative Position Of The Tunnels: A Numerical Study On Twin Tunnels,
2013
UVCE, Bangalore University, India
Influence Of Relative Position Of The Tunnels: A Numerical Study On Twin Tunnels, W. Channabasavaraj, B. Visvanath
International Conference on Case Histories in Geotechnical Engineering
The development of cities requires the use of underground area for the construction of transportation infrastructure facilities. Construction of twin tunnels or new tunnel close to the existing ones may be done horizontally, vertically or in inclined manner. In the case of horizontal tunnels the distribution of tunnel load will be more in lateral direction. Since cities are densely concentrated with tall structures, laterally distributed loads will induce settlement in the foundation of the structures. For a particular orientation of tunnels, the soil movement and internal forces in the lining will be affected by both the relative position of tunnels …
Amirkabir Natm Tunnel — A Case Study Of Design Challenges In A Mega Project Of Tunnel In Soft Ground,
2013
Tarbiat Modares University, Iran
Amirkabir Natm Tunnel — A Case Study Of Design Challenges In A Mega Project Of Tunnel In Soft Ground, Aliakbar Golshani, Ehsan Moradabadi
International Conference on Case Histories in Geotechnical Engineering
In spite of enhancement in modeling techniques as well as site investigation methods, uncertainty exists seriously in the process of construction of underground structure in soft soils. These uncertainties arise from limited data of geological data, measurement errors, interpolation of spatially geological properties, and extrapolation of results of experiments and natural analogue studies over times and conditions relevant to the project. Robust and optimize design of tunnel support pattern consists of many important parameters including advance rate and excavation method. However, quantitative definition of these parameters is difficult because of restricting in site investigation data and uncertainties related to them. …
Geotechnical And Geophysical Evaluation Of The Near Surface Faults And Cracks In Residential Area Underlain By Semi-Arid Shale,
2013
KACST, Oil and Gas Institute, Saudi Arabia
Geotechnical And Geophysical Evaluation Of The Near Surface Faults And Cracks In Residential Area Underlain By Semi-Arid Shale, Khaled Al-Mutairi, Muawia Dafalla, Fouzan Al Fouzan, Mosleh Al-Shamrani
International Conference on Case Histories in Geotechnical Engineering
This study was carried out following the development of abnormal faults and distresses that extend over more than two kilometers distance in an agricultural rural area to the North of Saudi Arabia. They appeared on the ground surface in the form of extended wide cracks and appeared across buildings, roads and green areas. Severe damages were inflicted to the existing structures and included cracks within the streets, the buildings and boundary walls. Geotechnical works carried out included advancing six boreholes to depths of 35 to 40 meters below grade. The subsurface soil profile was constructed and laboratory tests were carried …
Promotion Of Tunneling Performance In Locally Semi-Hard To Hard Conglomerate Lenses, Case Of Esfahan Historical City Subway Project,
2013
Zaminfanavaran (ZAFA) Consulting Engineers Co., Iran
Promotion Of Tunneling Performance In Locally Semi-Hard To Hard Conglomerate Lenses, Case Of Esfahan Historical City Subway Project, Amir Hossein Haghi, Ali Taheri, A. Ehsan Haghi
International Conference on Case Histories in Geotechnical Engineering
The highly inhomogeneous nature of the river deposits in central Esfahan induced unforeseen problems for tunneling of 2×5 km long of middle section of the Esfahan Subway Project. A noticeable phenomenon in these course grained fluvial (river) deposits is the locally cementation of the soil particles by a calcium carbonate binder and formation of some semi-hard to hard conglomerate lenses. This unique phenomenon is named locally as “Sovord” rock and could be seen just in semi-aired regions as central Iran. Two 6.89 m diameter EPBTBM machines were employed to excavate shallow tunnels in the vicinity of fragile structures of the …
Support System Design Of Power House And Transformer Caverns In Dikchu Hydropower Project, Sikkim,
2013
IIIT Hyderabad, India
Support System Design Of Power House And Transformer Caverns In Dikchu Hydropower Project, Sikkim, Neelima Satyam
International Conference on Case Histories in Geotechnical Engineering
The Dikchu hydropower project is 3 x 32 MW hydro power plant across river Dikchu in Sikkim, India. Dikchu is a tributary of River Teesta, a major river flowing right across Sikkim. The proposed hydro power project site is about 10 km upstream of the confluence of River Dikchu with River Teesta. Two more hydro power projects of NHPC, namely, Teesta Hydro Power Project Stage-IV and Teesta Hydro Power Project Stage-V on the River Teesta, are being commissioned upstream and downstream of the above mentioned confluence. Surface geological mapping indicated that quartzitic phyllite with bands of phyllites shear zones are …
Baltimore Red Line Project: An Overview Of The Cooks Lane Tunnel,
2013
AECOM, Boston, MA
Baltimore Red Line Project: An Overview Of The Cooks Lane Tunnel, Mohsen G. Kashi, Verya Nasri
International Conference on Case Histories in Geotechnical Engineering
The Maryland Transit Administration’s Baltimore Red Line is a proposed 14.1-mile east-west Light Rail Transit (LRT) line connecting the areas of Woodlawn, Edmondson Village, West Baltimore, downtown Baltimore, Inner Harbour East, Fells Point, Canton and the Johns Hopkins Bayview Medical Centre Campus. Red Line has two tunnel segments namely, the Downtown and the Cooks Lane Tunnels. The Cooks Lane Tunnel (CLT) is the shorter of the two tunnels and will connect the proposed at-grade LRT segment running alongside I-70 with the at-grade LRT segment along Edmondson Avenue. The western CLT portal will be west of the intersection of North Forest …
Foundation And Structural Design Of Lock Walls Founded On A Fault Zone,
2013
MWH, Chicago, IL
Foundation And Structural Design Of Lock Walls Founded On A Fault Zone, Rachael Bisnett, Joseph Kovacich, Juan Quiroz
International Conference on Case Histories in Geotechnical Engineering
The Panama Canal Third Set of Locks Project is being constructed within a geologically diverse setting. Of particular interest is the upper chamber of the Pacific Locks Complex, which is 400 meters long and founded on basalt bedrock but crosses a 90 m wide fault zone. After completing the excavation to foundation grade, the fault zone was mapped and drilling investigations, in-situ geomechanical testing, and laboratory testing were performed. The fault zone contains highly fractured, faulted, and brecciated rock types that were grouped into two geomechanical classes, Class I and Class II. Given the extent of the fault zone and …
Numerical Analysis To Examine The Effect Of Landslides On Tunnels,
2013
Nippon Koei Co., LTD. Research and Development Center, Japan
Numerical Analysis To Examine The Effect Of Landslides On Tunnels, Keiichi Ota, Senro Kuraoka, Toshiya Takeshi
International Conference on Case Histories in Geotechnical Engineering
In the vicinity of known landslide zones, tunnel routes should be designed such that the distance between the landslide and the tunnel is sufficient to avoid adverse impact of the landslide on the tunnel. This requires a good understanding of the effects of the landslide on the tunnel. We modeled the ground surrounding the tunnel and the landslide using numerical analysis to evaluate the quantitative effect of the tunnel offset from the landslide on ground stresses and displacement of the ground surface and tunnel crown. We considered the effects under different ground conditions and examined two different cases, when the …
Slope Stability Analysis Of The Working Level And Final Slope In The Surface Mine Of Marls Near 'Hani I Elezit',
2013
University of Tetovo, Macedonia
Slope Stability Analysis Of The Working Level And Final Slope In The Surface Mine Of Marls Near 'Hani I Elezit', Idaver Huseini, Januz Mehmeti, Nexhmi Krasniqi, Ahmet Bytyçi, Semijal Hasani-Ziberi
International Conference on Case Histories in Geotechnical Engineering
The future of Kosovo’s economic development relies on the exploration of natural resources, particularly, mining. Great importance has been placed on the exploitation of these resources via the surface utilization of marls. Marls being the prevalent raw material for cement production. Since the beginning of 20thcentury, great achievements have been made in the geo-techniques field, leading to the remarkable progress in the art of mining.This paper through the limit equilibrium solution examines the optimization of parameters for slope stability and presents the findings of the on-site research and lab workings conducted on the open-pit mines of marls near the cement …
Three Dimensional Numerical Analysis For Soft Ground Tunneling,
2013
AECOM, New York, NY
Three Dimensional Numerical Analysis For Soft Ground Tunneling, Navid Allahverdi, Verya Nasri
International Conference on Case Histories in Geotechnical Engineering
This paper presents the methodology and results of comprehensive three-dimensional finite element analyses which were performed to assess the potential impacts of tunneling under an existing subway tunnel as well as potential impact of tunneling under an existing bridge. The finite element models took into account all relevant components of the construction process including the soil behavior, shield tunneling, precast concrete segmental lining and the tail void grouting. The models also accounted for stage construction and detailed shield-driven tunnel boring machine (TBM) processes including applying balancing face pressure as well as injecting bentonite slurry through the TBM shield. This study …
