scholarly journals Relationship between Unconfined Compressive Strength and Shear Wave Velocity of Cemented Sands

2014 ◽  
Vol 30 (1) ◽  
pp. 65-74 ◽  
Author(s):  
Sung-Sik Park ◽  
Se-Hoon Hwang
2006 ◽  
Vol 43 (3) ◽  
pp. 310-324 ◽  
Author(s):  
Katherine Klein ◽  
Dragana Simon

This paper focuses on monitoring setting and strength development in cemented paste backfill (CPB). The composition of the paste is altered to study the effects of binder type and content, selected chemical admixtures (superplasticizers), mineral additives (e.g., fly ash), and pore fluid chemistry (e.g., ionic concentration and pH) on these properties. The three main techniques utilized are shear wave velocity measurements, penetration tests (e.g., Vicat needle tests), and unconfined compressive strength tests. All of these tests are sensitive to changes in the paste composition. The effect of the pore fluid chemistry and the chemical additives on the CPB properties depends on the ion type and concentration and the chemical composition of the superplasticizers. The shear wave velocity in both uncemented and cemented pastes increases with time as a result of self-weight consolidation, capillary forces, and cementation (the precipitation of ions in uncemented tailings pastes or cement hydration in cemented tailings pastes).Key words: cemented paste backfill, shear wave velocity, setting, unconfined compressive strength.


2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Byung Jae Lee ◽  
Seong-Hoon Kee ◽  
Taekeun Oh ◽  
Yun-Yong Kim

The objectives of this study are to investigate the relationship between static and dynamic elastic moduli determined using shear-wave velocity measurements and to demonstrate the practical potential of the shear-wave velocity method for in situ dynamic modulus evaluation. Three hundred 150 by 300 mm concrete cylinders were prepared from three different mixtures with target compressive strengths of 30, 35, and 40 MPa. Static and dynamic tests were performed at 4, 7, 14, and 28 days to evaluate the compressive strength and the static and dynamic moduli of the cylinders. The results obtained from the shear-wave velocity measurements were compared with dynamic moduli obtained from standard test methods (P-wave velocity measurements according to ASTM C597/C597M-16 and fundamental longitudinal and transverse resonance tests according to ASTM C215-14). The shear-wave velocity measured from cylinders showed excellent repeatability with a coefficient of variation (COV) less than 1%, which is as good as that of the standard test methods. The relationship between the dynamic elastic modulus based on shear-wave velocity and the chord elastic modulus according to ASTM C469/C469M was established. Furthermore, the best-fit line for the shear-wave velocity was also demonstrated to be effective for estimating compressive strength using an empirical relationship between compressive strength and static elastic modulus.


Solid Earth ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 379-390 ◽  
Author(s):  
Yaniv Darvasi ◽  
Amotz Agnon

Abstract. Instrumental strong motion data are not common around the Dead Sea region. Therefore, calibrating a new attenuation equation is a considerable challenge. However, the Holy Land has a remarkable historical archive, attesting to numerous regional and local earthquakes. Combining the historical record with new seismic measurements will improve the regional equation. On 11 July 1927, a rupture, in the crust in proximity to the northern Dead Sea, generated a moderate 6.2 ML earthquake. Up to 500 people were killed, and extensive destruction was recorded, even as far as 150 km from the focus. We consider local near-surface properties, in particular, the shear-wave velocity, as an amplification factor. Where the shear-wave velocity is low, the seismic intensity far from the focus would likely be greater than expected from a standard attenuation curve. In this work, we used the multichannel analysis of surface waves (MASW) method to estimate seismic wave velocity at anomalous sites in Israel in order to calibrate a new attenuation equation for the Dead Sea region. Our new attenuation equation contains a term which quantifies only lithological effects, while factors such as building quality, foundation depth, topography, earthquake directivity, type of fault, etc. remain out of our scope. Nonetheless, about 60 % of the measured anomalous sites fit expectations; therefore, this new ground-motion prediction equation (GMPE) is statistically better than the old ones. From our local point of view, this is the first time that integration of the 1927 historical data and modern shear-wave velocity profile measurements improved the attenuation equation (sometimes referred to as the attenuation relation) for the Dead Sea region. In the wider context, regions of low-to-moderate seismicity should use macroseismic earthquake data, together with modern measurements, in order to better estimate the peak ground acceleration or the seismic intensities to be caused by future earthquakes. This integration will conceivably lead to a better mitigation of damage from future earthquakes and should improve maps of seismic hazard.


Sign in / Sign up

Export Citation Format

Share Document