Geophysics and Seismology Commons^™

Temporal Lidar Scanning In Quantifying Cumulative Rockfall Volume And Hazard Assessment: A Case Study At Southwestern Saudi Arabia, Abdullah A. Alotaibi, Norbert H. Maerz, Kenneth J. Boyko, Ahmed M. Youssef, Biswajeet Pradhan

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Rockfalls and unstable slopes pose a serious threat to people and property along roads/highways in the southwestern mountainous regions of Saudi Arabia. In this study, the application of terrestrial light detection and ranging (LiDAR) technology was applied aiming to propose a strategy to analyze and accurately depict the detection of rockfall changes, calculation of rockfall volume, and evaluate rockfall hazards along the Habs Road, Jazan Region, Saudi Arabia. A series of temporal LiDAR scans were acquired at three selected sites. Our results show that these three sites have different degrees of hazard due to their geological differences. The mean volume …

Unsteady-State Contact Angle Hysteresis During Droplet Oscillation In Capillary Pores: Theoretical Model And Vof Simulation -- Supporting Information, Chao Zeng, Wen Deng, Lichun Wang

Research Data

Contact angle hysteresis (CAH) is a critical phenomenon that could significantly affect the fate of immiscible bubbles/droplets in vadose zones, nonaqueous phase liquid contaminated aquifers, and saline aquifers for CO₂ sequestration in terms of infiltration patterns and residual trapping mechanisms. When external physical impacts such as oscillatory excitation or pulse forcing are applied, it could result in pinned oscillation of droplets due to this CAH. Conventional steady-state analysis of contact angle could underestimate CAH. As the first time to take unsteady-state effect into consideration, a hydrodynamic analysis is developed in this study to address the unsteady-state CAH theoretically, and …

Stress-State Dependency Of The Deformation Ratio Of Quasi-Elastic Granular Soils Under Cyclic Loading -- Supporting Information, Pingxin Xia, Longtan Shao, Wen Deng

Research Data

Poisson’s ratio, besides its transverse-axial strain ratio definition, also plays a significant role in traditional elastic theory as an elastic constant. However, this elastic role of Poisson’s ratio faces a challenge when applied to quasi-elastic granular soils. A so-called “deformation ratio” is therefore introduced and measured in this paper for quasi-elastic granular soils. With the same definition of the transverse-axial strain ratio as Poisson’s ratio, the stress-state dependency of the deformation ratio and the break-down of conversion relationship of elastic constants are investigated under cyclic triaxial tests. The results show that Poisson’s ratio is consistent with deformation ratio only in …

Effect Of Subsurface Microseismicity On The Motion Of Surrounding Dispersed Droplets: Supporting Information, Chao Zeng, Wen Deng

Research Data

The human-induced seismicity has called substantial attention in recent years. The effect of seismicity on the subsurface structure has been extensively studied. However, the effect of seismicity, especially those microseismicity, on surrounding immiscible fluids is rarely investigated. In porous media with two or more immiscible fluids, different amplitudes of vibration induced by seismicity have distinct effects on the dynamic behavior of fluids. Three types of pore-scale models are prevalent in the analysis of the motion of immiscible droplets. The underlying assumptions and accuracy of these models are compared in this study in both frequency domain and time domain. The frequency …

Experimental Investigation Of The Dynamics Of Trapped Non-Wetting Droplets Subjected To The Seismic Stimulation In Constricted Tubes: Supporting Information, Yandong Zhang, Chao Zeng, Baojun Bai, Wen Deng

Research Data

• Aspect Ratio of 4.5
• Aspect Ratio of 9.0
• Video Demos

Sh-Mode Seismic-Reflection Imaging Of Earthfill Dams, Edward W. Woolery

Earth and Environmental Sciences Faculty Publications

Assessing subsurface characteristics and imaging geologic features (e.g., faults, cavities, low-velocity layers, etc.) are typical problems in near-surface geophysics. These questions often have adverse geotechnical engineering implications, and can be especially acute when associated with high-hazard structures such as large earthen flood-control dams. Dam-related issues are becoming more frequent in the United States, because a large part of this major infrastructure was designed and constructed in the early- to mid-twentieth century; these dams are thus passing into the latter stages of their design life, where minute flaws that were overlooked or thought to be insignificant in design/construction are now …

Scientific And Engineering Studies Of Systems, Structures, And Components Important To Safety For A Potential Repository At Yucca Mountain, Nevada, Ian Buckle, E. Manos Maragakis

Publications (YM)

TASK 26: Upgrade of Earthquake Simulation Facilities in the Large-Scale Structures Laboratory at University of Nevada Reno

The objective of this Task was to purchase, install and commission the equipment necessary to upgrade two existing shake tables in the Structures Laboratory at UNR, from uniaxial to biaxial motion.

It was recognized that a parallel effort, funded by NSF and HUD, to add a third biaxial table with identical properties to the upgraded existing tables, would be undertaken at the same time.