Geotechnical Engineering Commons^™

Geophysics-Based Ground Control And Excavation Design Methodology Based On Acceptable Damage, Jorge Romana Giraldo

Theses and Dissertations--Civil Engineering

This dissertation is structured around a novel conceptual framework for designing deep excavation retaining systems and using geophysical data to estimate the mechanical response of soft soil deposits. It begins with presenting an approach to design excavation retaining walls based on limiting damage to adjacent infrastructure. In this approach, the damage is defined based on critical distortions of an idealized laminate beam model used for representing the adjacent building deformations. The wall and support elements of the support system are then designed such that the system yields the limiting ground deformations. The resulting excavation support system limits damage to adjacent …

Young’S Modulus As A Measurement To Estimate Damage Related With Alkali-Silica Reaction In Concrete., Anazaria J. Ortega Gonzalez

Civil Engineering Undergraduate Honors Theses

The main purpose of this research is to compare two nondestructive methods to assess Alkali-Silica reaction (ASR) in concrete. Fifteen concrete prisms were cast using aggregates with different Alkali-Silica reactivity such as Jobe sand and Van Buren sand. The change in strain, shear wave velocity and Young’s modulus were determined according to ASTM C129 and ASTM C215, respectively. This data was collected by Dillon K Self, who determined that the shear wave velocity and strain are inversely proportional. However, when single cracking in the concrete specimen transition to map cracking, the shear wave velocity dropped significantly, whereas the strain value …

Robust Earthquake Site Classification Assessment At Ontario Bridge Sites., Alex Bilson Darko

Electronic Thesis and Dissertation Repository

Canadian seismic design guidelines classify subsurface ground conditions based on the average shear-wave velocity (V_S) of the upper 30 meters (V_S30). We seek to optimize a robust earthquake site classification procedure for Ontario bridge sites, assessed primarily from blind comparison of non-invasive V_S depth profiling techniques. Non-invasive seismic testing is performed at 10 bridge sites in southern Ontario co-located with invasive penetration and/or borehole V_S measurements. Non-invasive surface wave dispersion and site amplification functions are jointly inverted to retrieve V_S profiles at each site. A general correlation between corrected V_S and cone …

Static And Dynamic Properties Of Controlled Low-Strength Materials Incorporating Treated Oil Sands Waste, Ahmed Mneina

Electronic Thesis and Dissertation Repository

Controlled Low-Strength Materials (CLSM) is a self-compacted self-leveling cementitious material with compressive strength of 8.3 MPa or less. It is used as an alternative of soil backfill materials in geotechnical and infrastructure applications. This study investigates the effects of incorporating treated oil sand wastes (TOSW) as a partial replacement of sand or fly ash on fresh and hardened properties of CLSM. In addition, the environmental impact of the proposed new mixtures was evaluated. The results show that CLSM mixtures incorporating TOSW had satisfied the limits and requirements of ACI committee 229 for CLSM with no environmental hazards. The incorporation of …

Liquefaction Susceptibility Analysis Of Fraser River Sand In Miniature Cone Penetration Tests And Cyclic Direct Simple Shear Tests, Stephen Jones

Electronic Thesis and Dissertation Repository

The cone penetration test (CPT) and, its geophone-equipped form, the seismic cone penetration test (SCPT) are increasingly used site investigation techniques to determine in-situ geotechnical properties of soil profiles as well as liquefaction susceptibility in seismically active locations. The use of experimental techniques, most notably miniature cone penetration testing (MCPT), can be used to recreate these in-situ tests in a controlled laboratory setting.

In this study, MCPT tests are completed using Fraser River sand to determine cone tip and sleeve frictional resistances as well as shear wave velocity measurements and are validated using in-situ SCPT tests and existing soil classification …

Characterization Of A Carbonate Sand Based On Shear Wave Velocity Measurement, Abouzar Sadrekarimi, Keyvan Mirbaha

Civil and Environmental Engineering Presentations

Numerous studies have been carried out on the dynamic behavior of sands. However, few studies have investigated the dynamic characteristics of carbonate sands. This paper presents series of laboratory simple shear tests on specimens of a local carbonate sand from London (ON). Besides monotonic and cyclic shearing, the dynamic behavior of the sand is also characterized by measuring the velocity of shear waves travelling through the specimens. Drained and undrained shearing behavior of specimens with a wide range of relative density and consolidation stresses are tested. Shear wave velocity is found to vary with effective overburden stresses by an average …

Liquefaction Assessment Of Carbonate-Silica Silty Sands Using Energy, State Parameter And Shear Wave Velocity, Naemeh Naghavi

Electronic Thesis and Dissertation Repository

The liquefaction behaviour and dynamic properties of reconstituted natural carbonate-silica silty sand samples were investigated in a series of monotonic and cyclic triaxial tests. The critical state parameters of the mixtures with different levels of fines were obtained through monotonic triaxial compression tests. Bender element tests were performed at the consolidation stage to characterize soil’s initial state and small strain properties. The results demonstrated that soil contraction capacity, liquefaction potential and undrained brittleness increase by increasing the state parameter. A general correlation between shear wave velocity and state parameter was established. The susceptibility and triggering of liquefaction under cyclic loading …

Use Of Laboratory Geophysical And Geotechnical Investigation Methods To Characterize Gypsum Rich Soils, Raghava A. Bhamidipati

Theses and Dissertations--Civil Engineering

Gypsum rich soils are found in many parts of the world, particularly in arid and semi-arid regions. Most gypsum occurs in the form of evaporites, which are minerals that precipitate out of water due to a high rate of evaporation and a high mineral concentration. Gypsum rich soils make good foundation material under dry conditions but pose major engineering hazards when exposed to water. Gypsum acts as a weak cementing material and has a moderate solubility of about 2.5 g/liter. The dissolution of gypsum causes the soils to undergo unpredictable collapse settlement leading to severe structural damages. The damages incur …

Cyclic And Post-Cyclic Response Of Silt And Sandy Silt Soils, Ali El Takch

Electronic Thesis and Dissertation Repository

A series of cyclic and monotonic constant-volume ring shear tests were carried out to determine the cyclic and post-cyclic response of silts and sandy silts with 25% and 50% sand. The elastic soil behavior at very small shear strain (γ < 10^-4%) was investigated through shear wave velocity (Vs) measurements using bender elements at vertical stresses ranging from 50 to 300 kPa, while strain-controlled constant volume cyclic ring shear tests were conducted to establish shear modulus (G) and damping ratio (D) at larger shear strain amplitudes (γ > 0.01%). Liquefaction and strain-softening occurred at excess pore water pressure ratios (r_{u …}