HU Q Z, CHEN Y Y, ZHUANG X S, et al． Experimental Study on Physical and Mechanical Properties of Polypropylene Fiber Lightweight Soil[J]. Journal of Henan Polytechnic University( Natural Science) , doi: 10.16186/j.cnki.1673-9787.2024060006

doi: 10.16186/j.cnki.1673-9787. 2024060006

Received： 2024-06-05

Revised： 2024-08-29

Online： 2025-03-07

Experimental study on physical and mechanical properties of polypropylene fiber lightweight soil (Online)

HU Qizhi^1,2, CHEN Yuyi¹, ZHUANG Xinshan^1,2, LIU Yiming^1,2, TAO Gaoliang^1,2

1.School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068，Hubei，China；2.Hubei Bridge Safety Monitoring Technology and Equipment Engineering Center,Wuhan 430068，Hubei，China

Abstract: Objectives Lightweight soils obtained by adding polypropylene fibers, EPS particles, and cement to clay can be used as fillers to effectively reduce post-work settlement in fill areas. Methods Design polypropylene fiber, EPS particles and cement as three factors affecting the lightweight soil, take four different dosages of each factor as four levels, using L16 (4³) orthogonal experimental design to obtain 16 combinations, respectively, to carry out the unconfined compressive strength test and density test of the lightweight soil samples with different factors and different levels; through the analysis of extreme deviation and analysis of variance, to study the influence of the different factors and levels on the performance law of the lightweight soil; analyze the effect of polypropylene fiber, EPS particles, and cement on the performance of the lightweight soil. Through the polar analysis and Analysis of Variance, the influence of different factors and levels on the performance of lightweight soil is studied; the damage characteristics of polypropylene fiber and EPS particles on the unconfined compressive strength are analyzed, and the mechanical properties were analyzed by SEM scanning. Results The results of the study found that: the order of influence on the strength of lightweight soil is "cement dosing > EPS particles dosing > fiber dosing", and the order of influence on the density is "EPS particles dosing > cement dosing > fiber dosing"; the density and unconfined compressive strength of lightweight soil increase with the dosage of cement. The density and unconfined compressive strength of lightweight soil increased significantly with the increase of cement dosage, but decreased with the increase of EPS dosage; the addition of fiber can effectively improve the strength of lightweight soil, so that the crack resistance of the soil body increases, and make the lightweight soil has a certain degree of residual strength, but more than the optimal dosage of lightweight soil strength has decreased.Conclusions The research results provide a theoretical basis for improving the physical and mechanical properties of polypropylene fiber lightweight soil, and have a certain reference for the application of lightweight soil in practical engineering.

Key words: polypropylene fiber; lightweight soil; orthogonal test; unconfined compressive strength