Collapse Potential and Geotechnical Characterization of Sandy Loess-Like Deposits in Southern Vietnam

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985891%3A_____%2F25%3A00638877" target="_blank" >RIV/67985891:_____/25:00638877 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1007/s10706-025-03288-8" target="_blank" >https://doi.org/10.1007/s10706-025-03288-8</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s10706-025-03288-8" target="_blank" >10.1007/s10706-025-03288-8</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Collapse Potential and Geotechnical Characterization of Sandy Loess-Like Deposits in Southern Vietnam

Popis výsledku v původním jazyce

The collapse potential of loess is a distinctive geotechnical property influenced by moisture variation. In southern Vietnam, the collapse potential and geotechnical characteristics of a sandy loess-like deposit (SLD) have not been fully investigated. This study addresses this gap through in situ and laboratory testing. The SLD is classified as silty sand, comprising well-sorted fine sand with silt and clay. Coarse grains are sub-angular to sub-rounded, coated with clay, forming a metastable open structure characteristic of aeolian deposits. Plate load testing at the natural moisture content and saturation level (w= 5.6%, S= 32.3%) under 70 kPa stress showed no collapse, but immediate collapse occurred after saturation. Laboratory oedometer testing under saturated conditions (w= 17.3%, S= 99.8%) and 200 kPa stress revealed moderate collapse (collapse potential index δ= 4.4%), consistent with in situ testing (δ= 5.1%). Cone penetration resistance (qc= 4.2–9.8 MPa) decreases with increasing moisture content (w= 2.3–10.0%), dropping to 2.0–4.3 MPa under saturated conditions (w= 15.1–17.3%, S= 87.1–99.8%). The undrained shear strength is 76 kPa with a sensitivity of 3.8. Compacted soil yields a maximum dry unit weight of 18.3 kN/m3 at 10.6% moisture. Cohesion strongly affects compacted soil shear strength. At 50 kPa normal stress, shear strength and cohesion decrease by 24.2% and 67.9%, respectively. Over four weeks at optimum moisture, shear strength rises by 28.9% as cohesion improves. The SLD has lower collapse potential than the sandy yellow loess in northeastern Thailand, but still requires careful foundation assessment as a soft soil.

Název v anglickém jazyce

Collapse Potential and Geotechnical Characterization of Sandy Loess-Like Deposits in Southern Vietnam

Popis výsledku anglicky

The collapse potential of loess is a distinctive geotechnical property influenced by moisture variation. In southern Vietnam, the collapse potential and geotechnical characteristics of a sandy loess-like deposit (SLD) have not been fully investigated. This study addresses this gap through in situ and laboratory testing. The SLD is classified as silty sand, comprising well-sorted fine sand with silt and clay. Coarse grains are sub-angular to sub-rounded, coated with clay, forming a metastable open structure characteristic of aeolian deposits. Plate load testing at the natural moisture content and saturation level (w= 5.6%, S= 32.3%) under 70 kPa stress showed no collapse, but immediate collapse occurred after saturation. Laboratory oedometer testing under saturated conditions (w= 17.3%, S= 99.8%) and 200 kPa stress revealed moderate collapse (collapse potential index δ= 4.4%), consistent with in situ testing (δ= 5.1%). Cone penetration resistance (qc= 4.2–9.8 MPa) decreases with increasing moisture content (w= 2.3–10.0%), dropping to 2.0–4.3 MPa under saturated conditions (w= 15.1–17.3%, S= 87.1–99.8%). The undrained shear strength is 76 kPa with a sensitivity of 3.8. Compacted soil yields a maximum dry unit weight of 18.3 kN/m3 at 10.6% moisture. Cohesion strongly affects compacted soil shear strength. At 50 kPa normal stress, shear strength and cohesion decrease by 24.2% and 67.9%, respectively. Over four weeks at optimum moisture, shear strength rises by 28.9% as cohesion improves. The SLD has lower collapse potential than the sandy yellow loess in northeastern Thailand, but still requires careful foundation assessment as a soft soil.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20701 - Environmental and geological engineering, geotechnics

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Geotechnical and Geological Engineering

ISSN

0960-3182

e-ISSN

1573-1529

Svazek periodika

43

Číslo periodika v rámci svazku

7

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

16

Strana od-do

326

Kód UT WoS článku

001559625500043

EID výsledku v databázi Scopus

2-s2.0-105013867197