Suitability of earthen materials for rammed earth in arid region

This study investigated the suitability of two engineered earthen materials manufactured by mixing different proportions of sand, silt, and clay for rammed earth constructions under dry conditions. The first mix contained 30 % fine material, whereas the second mix contained 50 % fine material. Test...

Full description

Saved in:
Bibliographic Details
Main Authors: Hasan Eanas, Al-Sharrad Muayad
Format: Article
Language:English
Published: Peter the Great St. Petersburg Polytechnic University 2024-07-01
Series:Magazine of Civil Engineering
Subjects:
Online Access:http://engstroy.spbstu.ru/article/2024.128.07/
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850199566895284224
author Hasan Eanas
Al-Sharrad Muayad
author_facet Hasan Eanas
Al-Sharrad Muayad
author_sort Hasan Eanas
collection DOAJ
description This study investigated the suitability of two engineered earthen materials manufactured by mixing different proportions of sand, silt, and clay for rammed earth constructions under dry conditions. The first mix contained 30 % fine material, whereas the second mix contained 50 % fine material. Test specimens were prepared by static compaction to 4.5, 25, 50, and 100 MPa, equilibrated at relative humidity values of RH = 35 % and RH = 55 % and tested in the lab to characterize plasticity, mechanical, hydric, and thermal behavior. The materials showed a drying shrinkage of no more than 4 %, depending on the initial water content and the unit weight of the material. The results indicated a remarkable increase in materials elastic stiffness and strength of 50 % to 120 % and 10 % to 70 %, respectively, with increasing dry unit weight or compaction energy. The increase in soil suction led to a profound improvement in stiffness and strength, owing to an increase in capillary bonding. In addition, the increase in finer content from 30 % to 50 % significantly enhanced the mechanical behavior. If a minimum compressive strength of 2 MPa is considered, then compacting the earthen material to 50 MPa or greater would provide sufficient strength under the operational humidity RH=55 %. For the mix with 50 % finer content, a compressive strength of almost 5.75 MPa was achieved when the material was compacted to 100 MPa and equalized to RH = 55 %. As relative humidity increased, materials strength decreased where the amount of reduction was found to be inversely proportional to the compaction level and the maximum dry unit weight. The dynamic adsorption behavior was, largely, independent of the amount of compaction energy or finer content. The dynamic adsorption test indicated that the tested materials exchange a considerable amount of moisture with the atmosphere. Compared to traditional brick and concrete blocks, the materials showed good insulation characteristics. It was observed that the increase in finer content yielded slightly higher thermal conductivity values. Overall, the engineered material examined in this work can be potentially used for rammed earth under dry conditions.
format Article
id doaj-art-9e8cadfbda9840b5bc73c69663f1f351
institution OA Journals
issn 2712-8172
language English
publishDate 2024-07-01
publisher Peter the Great St. Petersburg Polytechnic University
record_format Article
series Magazine of Civil Engineering
spelling doaj-art-9e8cadfbda9840b5bc73c69663f1f3512025-08-20T02:12:34ZengPeter the Great St. Petersburg Polytechnic UniversityMagazine of Civil Engineering2712-81722024-07-0117410.34910/MCE.128.720714726Suitability of earthen materials for rammed earth in arid regionHasan Eanas0Al-Sharrad Muayad1https://orcid.org/0000-0001-6180-8837University of AnbarUniversity of AnbarThis study investigated the suitability of two engineered earthen materials manufactured by mixing different proportions of sand, silt, and clay for rammed earth constructions under dry conditions. The first mix contained 30 % fine material, whereas the second mix contained 50 % fine material. Test specimens were prepared by static compaction to 4.5, 25, 50, and 100 MPa, equilibrated at relative humidity values of RH = 35 % and RH = 55 % and tested in the lab to characterize plasticity, mechanical, hydric, and thermal behavior. The materials showed a drying shrinkage of no more than 4 %, depending on the initial water content and the unit weight of the material. The results indicated a remarkable increase in materials elastic stiffness and strength of 50 % to 120 % and 10 % to 70 %, respectively, with increasing dry unit weight or compaction energy. The increase in soil suction led to a profound improvement in stiffness and strength, owing to an increase in capillary bonding. In addition, the increase in finer content from 30 % to 50 % significantly enhanced the mechanical behavior. If a minimum compressive strength of 2 MPa is considered, then compacting the earthen material to 50 MPa or greater would provide sufficient strength under the operational humidity RH=55 %. For the mix with 50 % finer content, a compressive strength of almost 5.75 MPa was achieved when the material was compacted to 100 MPa and equalized to RH = 55 %. As relative humidity increased, materials strength decreased where the amount of reduction was found to be inversely proportional to the compaction level and the maximum dry unit weight. The dynamic adsorption behavior was, largely, independent of the amount of compaction energy or finer content. The dynamic adsorption test indicated that the tested materials exchange a considerable amount of moisture with the atmosphere. Compared to traditional brick and concrete blocks, the materials showed good insulation characteristics. It was observed that the increase in finer content yielded slightly higher thermal conductivity values. Overall, the engineered material examined in this work can be potentially used for rammed earth under dry conditions.http://engstroy.spbstu.ru/article/2024.128.07/earthen materialsrammed earthsustainable buildingsdynamic adsorption
spellingShingle Hasan Eanas
Al-Sharrad Muayad
Suitability of earthen materials for rammed earth in arid region
Magazine of Civil Engineering
earthen materials
rammed earth
sustainable buildings
dynamic adsorption
title Suitability of earthen materials for rammed earth in arid region
title_full Suitability of earthen materials for rammed earth in arid region
title_fullStr Suitability of earthen materials for rammed earth in arid region
title_full_unstemmed Suitability of earthen materials for rammed earth in arid region
title_short Suitability of earthen materials for rammed earth in arid region
title_sort suitability of earthen materials for rammed earth in arid region
topic earthen materials
rammed earth
sustainable buildings
dynamic adsorption
url http://engstroy.spbstu.ru/article/2024.128.07/
work_keys_str_mv AT hasaneanas suitabilityofearthenmaterialsforrammedearthinaridregion
AT alsharradmuayad suitabilityofearthenmaterialsforrammedearthinaridregion