Shear strength enhancement at the sand-steel interface: A pioneering approach with Polyurethane Foam Adhesive (PFA)

Feng，Wei Qiang1,2; Bayat，Meysam1,3; Mousavi，Zohreh1; Li，Ai Guo4; Lin，Jian Fu5

2024-05-24

10.1016/j.conbuildmat.2024.136297

Construction and Building Materials   影响因子和分区

0950-0618

This study explores a novel application of Polyurethane Foam Adhesive (PFA) injection to augment shear resistance at the interface, investigating various parameters such as PFA content, injection pressure, curing time, sand density, and surface roughness. Results demonstrate that injecting 10 % PFA increased the friction angle (ϕ) from 6.4 to 27.4° and 32.6–42° for sand-smooth and rough surface interfaces, respectively, under relative density (D) of 30 %. Correspondingly, cohesion (c) values rose from 0 to 124 and 62 kPa. Samples with lower D (30 %) exhibited a more significant increase in shear strength post-PFA injection, attributed to PFA penetration and enhanced shear performance of loose sands, showing a maximum 23 % difference compared to D = 90 % for the sand-smooth surface interface. Curing time notably influenced injected samples, particularly at lower normal stress levels, leading to increased mobilized shear strength with longer curing periods, with 28-day shear strength averaging 2.34 and 2.74 times higher than one-hour shear strength for smooth and rough surfaces, respectively. A substantial shear strength increase was observed one hour after injection, with more pronounced behavior after seven days. Additionally, increased injection pressure expanded the stabilized area at the interface, enhancing mobilized shear strength. At the sand-smooth surface interface, increasing injection pressure from 25 to 225 kPa resulted in average mobilized shear strength increases of 84% and 117% for D 30 % and 90 %, respectively. Examination under a Scanning Electron Microscope (SEM) revealed that the inclusion of PFA additive serves to interconnect adjacent grains, consequently enhancing the mechanical properties of the mixture.

Direct shear test Injection Interface Pile Polyurethane Sand

SCI ; EI

英语

第一 ; 通讯

MATERIALS SCIENCE

2-s2.0-85191842935

Scopus

1.Department of Ocean Science and Engineering,Southern University of Science and Technology,Shenzhen,China
2.Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou),Guangzhou,China
3.Department of Civil Engineering,Najafabad Branch,Islamic Azad University,Najafabad,Iran
4.Shenzhen Geotechnical Investigation & Surveying Institute Co. Ltd.,Shenzhen,China
5.Center of Safety Monitoring of Engineering Structures,Shenzhen Academy of Disaster Prevention and Reduction,China Earthquake Administration,Shenzhen,518003,China

Feng，Wei Qiang,Bayat，Meysam,Mousavi，Zohreh,et al. Shear strength enhancement at the sand-steel interface: A pioneering approach with Polyurethane Foam Adhesive (PFA)[J]. Construction and Building Materials,2024,429.

Feng，Wei Qiang,Bayat，Meysam,Mousavi，Zohreh,Li，Ai Guo,&Lin，Jian Fu.(2024).Shear strength enhancement at the sand-steel interface: A pioneering approach with Polyurethane Foam Adhesive (PFA).Construction and Building Materials,429.

Feng，Wei Qiang,et al."Shear strength enhancement at the sand-steel interface: A pioneering approach with Polyurethane Foam Adhesive (PFA)".Construction and Building Materials 429(2024).