Improved empirical hard rock pillar strength predictions using unconfined compressive strength as a proxy for brittleness

This work aims to investigate different predictive models for estimating the unconfined compressive strength and the maximum peak strain of non-structural recycled concretes made up by ceramic and concrete wastes. The extensive experimental campaign carried out during this research includes granulometric analysis, physical and chemical analysis, and compression tests along with the use of the 3D digital image correlation as a method to estimate the maximum peak strain. The results obtained show that it is possible to accurately estimate the unconfined compressive strength for both types of concretes, as well as the maximum peak strain of concretes made up by ceramic waste. The peak strain for mixtures with concrete waste shows lower correlation values.

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Characterization and Comparison Research on Composite of Alluvial Clayey Soil Modified with Fine Aggregates of Construction Waste and Fly Ash

Science and Engineering of Composite Materials ◽

10.1515/secm-2021-0008 ◽

2021 ◽

Vol 28 (1) ◽

pp. 83-95

Author(s):

Qu Jili ◽

Wang Junfeng ◽

Batugin Andrian ◽

Zhu Hao

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Unconfined Compressive Strength ◽

Clayey Soil ◽

Dry Density ◽

Maximum Dry Density ◽

Construction Waste ◽

Comparison Research ◽

Fine Aggregates ◽

Optimum Water Content

Abstract Fine aggregates of construction waste and fly ash were selected as additives to modify the characteristics of Shanghai clayey soil as a composite. The laboratory tests on consistency index, maximum dry density, and unconfined compressive strength were carried out mainly for the purpose of comparing the modifying effect on the composite from fine aggregates of construction waste with that from fly ash. It is mainly concluded from test results that the liquid and plastic limit of the composites increase with the content of two additives. But their maximum dry density all decreases with the additive content. However, fine aggregates of construction waste can increase the optimum water content of the composites, while fly ash on the contrary. Finally, although the two additive all can increase the unconfined compressive strength of composites, fly ash has better effect. The current conclusions are also compared with previous studies, which indicates that the current research results are not completely the same as those from other researchers.

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Experimental Study on Improvement of Marine Soft Soil with Alkali Residue

E3S Web of Conferences ◽

10.1051/e3sconf/20185304021 ◽

2018 ◽

Vol 53 ◽

pp. 04021

Author(s):

SHAO Yong ◽

LIU Xiao-li ◽

ZHU Jin-jun

Keyword(s):

Experimental Study ◽

Compressive Strength ◽

Unconfined Compressive Strength ◽

Void Ratio ◽

Soft Soil ◽

Compressive Modulus ◽

Engineering Properties ◽

Test Results ◽

Use Of Resources ◽

One Year

Industrial alkali slag is the discharge waste in the process of alkali production. About one million tons of alkali slag is discharged in China in one year. It is a burden on the environment, whether it is directly stacked or discharged into the sea. If we can realize the use of resources, it is a multi-pronged move, so alkali slag is used to improve solidified marine soft soil in this paper. The test results show that the alkali residue can effectively improve the engineering properties of marine soft soil. Among them, the unconfined compressive strength and compressive modulus are increased by about 10 times, and the void ratio and plasticity index can all reach the level of general clay. It shows that alkali slag has the potential to improve marine soft soil and can be popularized in engineering.

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Stochastic assessment of hard rock pillar stability based on the geological strength index system

Geomechanics and Geophysics for Geo-Energy and Geo-Resources ◽

10.1007/s40948-021-00243-8 ◽

2021 ◽

Vol 7 (2) ◽

Author(s):

Chuanqi Li ◽

Jian Zhou ◽

Danial Jahed Armaghani ◽

Wenzhuo Cao ◽

Saffet Yagiz

Keyword(s):

Index System ◽

Hard Rock ◽

Geological Strength Index ◽

Strength Index ◽

Pillar Stability ◽

Rock Pillar

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Determining the unconfined compressive strength of indurated volcanic-ash materials. Technical note

International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts ◽

10.1016/0148-9062(93)92782-l ◽

1993 ◽

Vol 30 (3) ◽

pp. A145

Keyword(s):

Compressive Strength ◽

Unconfined Compressive Strength ◽

Volcanic Ash ◽

Technical Note

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An Experiment for Effects of Different Additives on Strength of Sediment Solidification

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.357-360.1235 ◽

2013 ◽

Vol 357-360 ◽

pp. 1235-1240 ◽

Cited By ~ 1

Author(s):

Guan Huan Chen ◽

Jian Zhong Zhu

Keyword(s):

Compressive Strength ◽

Electron Microscope ◽

Unconfined Compressive Strength ◽

Scan Electron Microscope ◽

Dredged Sediment ◽

Comparative Tests ◽

Cement Based Materials

The solidification method is a significant and resultful method for the disposal of dredged sediment. Solidified agents can be employed to improve the unconfined compressive strength (UCS) of sediment solidification. In this work, considering of economy and practicability, three kinds of optimized compound additives are selected and investigated on the effects of UCS of sediment solidification. 7d., 14d.and 28d. solidification stadium were taken to test the UCS of samples. Results showed that the activator had the best effect on increasing the UCS. The comparative tests also indicated that adding any kind of additive into the cement-based materials could improve the UCS of sediment solidification, the highest value of UCS was 11.02MPa (SCAHR). By means of scan electron microscope (SEM) technology, the microstructure images of the raw sample and solidified sample were obtained, which help to understand the development of UCS of the solidified sediments.

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