1 Introduction
1.1 Actuality of Durability
1.2 The Contradiction of Cement Stabilization
1.3 Terminology and Content of the Review
1.3.1 Soil
1.3.2 Durability of Earth Walls
1.3.3 Deterioration of Earthen Walls
1.3.4 Stabilization of Soils Used for Construction
1.3.5 Categorization of Durability Assessment Methods
1.3.6 Content of the Review
Study data | Base soil | Stabilization type | ||||
---|---|---|---|---|---|---|
Physical | Chemical | Mechanical | ||||
Reference | Technique | USDA class | USCS class | yes/no/both | yes/no/both | yes/no/both |
Heathcote (2002) | A, CEB, RE | Multiple | 2 | 1 | 0 | |
CEB | Multiple | 1 | 1 | 0 | ||
Kerali and Thomas ( 2004) | CEB | Sandy loam | Clayey sand | 1 | 1 | 0 |
Walker (2004) | CEB | Multiple | Clayey sand | 2 | 2 | 0 |
Guettala et al. (2006) | CEB | Sandy loam | Clayey sand | 1 | 1 | 0 |
Krisnaiah and Suryanarayana Reddy (2008) | CEB | Sandy loam | Clayey sand | 1 | 1 | 0 |
Forster et al. (2008) | C | Sandy clay loam | Clayey sand | 2 | 0 | 0 |
Hall and Djerbib (2006) | RE | Multiple | 1 | 2 | 0 | |
Bui et al. (2009) | RE | Multiple | 2 | 2 | 0 | |
Reddy and Kumar (2011) | RE | Multiple | 2 | 2 | 2 | |
Alavéz-Ramírez et al. (2012) | CEB | Loamy sand | Silty sand | 0 | 2 | 0 |
Cid-Falceto et al. (2012) | CEB | Loamy sand | Clayey sand | 0 | 2 | 0 |
Erkal et al. (2012) | RE | n/a | n/a | 0 | 0 | 0 |
Dahmen (2015) | RE | Multiple | 1 | 0 | 0 | |
Danso et al. (2015) | CEB | Sandy clay | Highly plastic clay | 2 | 0 | 0 |
Morton and Little (2015) | All | Multiple | 2 | 2 | 0 | |
Narloch et al. (2015) | RE | Sandy loam | Clayey sand | 1 | 2 | 0 |
Aguilar et al. (2016) | n/a | Clay loam | Low-plasticity clay | 0 | 2 | 0 |
Kariyawasam and Jayasinghe (2016) | RE | Sandy loam/sandy clay loam | n/a | 0 | 1 | 0 |
Stazi et al. (2016) | P, C, RE | Silty clay loam | Low-plasticity clay | 1 | 2 | 0 |
Arrigoni et al. (2017) | RE | Multiple | 2 | 2 | 0 | |
Eires et al. (2017) | CEB, RE | Loamy sand | Clayey sand | 0 | 2 | 0 |
Nakamatsu et al. (2017) | n/a | Clay loam | Low-plasticity clay | 0 | 2 | 0 |
Seco et al. (2017) | CEB | n/a | Low-plasticity clay | 2 | 1 | 0 |
Suresh and Anand (2017) | RE | Sandy clay loam | Clayey sand | 0 | 1 | 0 |
Raj et al. (2018) | RE | Sand | Well graded sand | 1 | 1 | 0 |
Study data | Test types | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Accelerated | Indirect | Simulation | ||||||||||
Reference | Technique | Spray test | Drip test | Rainfall test | Slake test | Wire brush test | Wet-dry strength ratio | Capillary water absorption test | Total water absorption test | Water absorption test under static pressure | Freeze–thaw cycle test | Location |
Heathcote (2002) | A, CEB, RE | X | Syndey, Australia | |||||||||
CEB | X | |||||||||||
Kerali and Thomas ( 2004) | CEB | X | ||||||||||
Walker (2004) | CEB | X | X | X | ||||||||
Guettala et al. (2006) | CEB | X | X | X | X | X | X | Biskra, Algeria | ||||
Krisnaiah and Suryanarayana Reddy (2008) | CEB | X | ||||||||||
Forster et al. (2008) | C | Xa | ||||||||||
Hall and Djerbib (2006) | RE | X | X | X | ||||||||
Bui et al. (2009) | RE | Grenoble, France | ||||||||||
Reddy and Kumar (2011) | RE | X | ||||||||||
Alavéz-Ramírez et al. (2012) | CEB | X | ||||||||||
Cid-Falceto et al. (2012) | CEB | X | X | |||||||||
Erkal et al. (2012) | RE | X | ||||||||||
Dahmen (2015) | RE | Boston, USA | ||||||||||
Danso et al. (2015) | CEB | X | X | X | ||||||||
Morton and Little (2015) | All | Multiple, UK | ||||||||||
Narloch et al. (2015) | RE | X | ||||||||||
Aguilar et al. (2016) | n/a | X | ||||||||||
Kariyawasam and Jayasinghe (2016) | RE | X | X | X | ||||||||
Stazi et al. (2016) | P, C, RE | X | X | X | ||||||||
Arrigoni et al. (2017) | RE | X | X | |||||||||
Eires et al. (2017) | CEB, RE | X | X | X | ||||||||
Nakamatsu et al. (2017) | n/a | X | Lima, Peru | |||||||||
Seco et al. (2017) | CEB | X | X | X | X | Pamplona, Spain | ||||||
Suresh and Anand (2017) | RE | X | ||||||||||
Raj et al. (2018) | RE | X |
2 A Brief History of Durability Assessment Methods
2.1 Previous Reviews in the Field
2.2 Early Wire-Brush Test
2.3 Development of the Spray Tests
2.4 Development of the Drip Tests
2.5 Establishing the Permeability and Slake Tests
2.6 Relating Compressive Strength to Durability Performance
3 Recent Accelerated Erosion Testing
3.1 Spray Erosion tests
Reference | Sample data | Test procedure | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Sample size | Sample shape | Curing conditions | |||||||||||
Width (mm) | Length (mm) | Height (mm) | Shape | Temperature (°C) | RH (%) | Time (days) | Reference | Nozzle diameter (mm) | Water pressure at nozzle (kPa) | Distance of rose from sample (mm) | Diameter of sprayed area (mm) | Test duration (min) | |
Guettala et al. (2006) | 100 | 100 | 200 | Prismatic | 20 | > 70 | 27 | Doat et al. (1979) | n/a | 0.016 | 180 | – | 120 |
Suresh and Anand (2017) | 150 | 150 | 150 | Prismatic | Room | High | 28 | IS 1725 | 100 | 140 | 180 | – | 120 |
Raj et al. (2018) | 150 | 150 | 150 | Prismatic | Room | High | 28 | ||||||
Walker (2004) | 140 | 295 | 45 | Prismatic | Room | > 70 | 28 | HB 195 | – | 50 | 470 | 150 | 60 |
Kariyawasam and Jayasinghe (2016) | 240* | 240* | 140* | Prismatic | n/a | n/a | n/a | ||||||
Arrigoni et al. (2017) | 180 | 180 | 160 | Prismatic | 21 ± 1 | 96 ± 2 | 28 | ||||||
Heathcote (2002) | 150 | 150 | 120 | Cylindrical | Room | Room | 28 | Mod. Bulletin 5 | 153 | 60–130 | 470 | 150 | 60–180 |
Eires et al. (2017) | 200 | 200 | 200 | Prismatic | Room* | Room* | 56 | Bulletin 5 | 153 | 50 | 470 | 150 | 60 |
Cid–Falceto et al. (2012) | 166 | 306 | 103 | Prismatic | n/a | n/a | n/a | NZS 4298 | 153 | 50 | 470 | 150 | 60 |
140 | 295 | 90 | Prismatic | n/a | n/a | n/a | |||||||
Narloch et al. (2015) | 300 | 300 | 200 | Prismatic | 20 | high | 27 | ||||||
Danso et al. (2015) | 140 | 290 | 100 | Prismatic | 27 | 72 | 21 | ||||||
Stazi et al. (2016) | 300 | 1000 | 1000 | Wall | Room | room | 90 | ||||||
250 | 250 | 20 | Plaster | Room | room | 15 |
3.1.1 Spray Testing by K.A. Heathcote, Sydney, Australia
3.1.2 Spray Testing by P. Walker, Bath, UK
3.1.3 Spray Testing by A. Guettala et al. Biskra, Algeria
3.1.4 Spray Testing by J. Cid-Falceto et al. Madrid, Spain
3.1.5 Spray Testing by P. L. Narloch et al. Warsaw, Poland
3.1.6 Spray Testing by K.K.G.K.D. Kariyawasam & C. Jayasinghe, Moratuwa, Sri Lanka
3.1.7 Spray Testing by F. Stazi et al. Ancona, Italy
3.1.8 Spray Testing by A. Arrigoni et al. Milano, Italy
3.1.9 Spray Testing by R. Eires et al. Braga, Portugal
3.1.10 Spray Testing by A. Suresh and K.B. Anand, Coimbatore, India
3.1.11 Spray Testing by S. Raj S. et al. Coimbatore, India
3.2 Drip Erosion Tests
Reference | Sample Data | Drip erosion test | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Sample size | Sample shape | Curing conditions | |||||||||||
Width (mm) | Length (mm) | Height (mm) | Shape | Temperature (°C) | RH (%) | Time (days) | Test procedure | Test duration (min) | Fall height (mm) | Water released (ml) | Angle of impact to surface (°) | Weight of dripped water to sample (%)a | |
Erkal et al. (2012) | 105 | 220 | 67 | Prismatic | 110 | n/a | 3 | Unique | n/a | 3200/4000 | 400/900 | 5–45 | 13/30 |
Cid-Falceto et al. (2012) | 166 | 306 | 103 | Prismatic | n/a | n/a | n/a | UNE 41410 | 10 | 1000 | 500 | 63 | 5 |
140 | 295 | 90 | Prismatic | n/a | n/a | n/a | 7 | ||||||
Aguilar et al. (2016) | 55 | 55 | 10 | Cylindrical | 20 | 60 | 7 | 826 | |||||
Nakamatsu et al. (2017) | 55 | 55 | 10 | Cylindrical | 20 | 60 | 7 | 826 | |||||
Seco et al. (2017) | 65 | 65 | 75 | Cylindrical | 20 | 100 | 28 | 79 | |||||
Stazi et al. (
2016) | 300 | 1000 | 1000 | Wall | Room | Room | 90 | NZS 4298 | 20–60 | 400 | 100 | 63 | 0 |
250 | 250 | 20 | Plaster | Room | Room | 15 | 4 |
3.2.1 Drip Erosion Tests by J. Cid-Falceto et al. Madrid, Spain
3.2.2 Drip Erosion Tests by Erkal et al. Bath, UK
3.2.3 Drip Erosion Tests by F. Stazi et al. Ancona, Italy
3.2.4 Drip Erosion Tests by R. Aguilar et al. Lima. Peru
3.2.5 Drip Erosion Tests by J. Nakamatsu et al. Lima. Peru
3.2.6 Drip Erosion Tests by A. Seco et al. Pamplona, Spain
3.3 Rainfall Simulation Test
3.3.1 The Experiments of Ogunye & Boussabaine
3.4 Slake Durability Test
3.4.1 A Quick Test Suggested by A. G. Kerali & T. H:Thomas, Kampala, Uganda
3.5 Indirect Tests
3.6 Wet to Dry Strength Ratio
Reference | Sample data | Wet to dry strength | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Sample size | Sample shape | Curing conditions | ||||||||||
Width (mm) | Length (mm) | Height (mm) | Shape | Temperature (°C) | RH (%) | Time (days) | Age (days) | Test procedure | definition of dry state | definition of wet state | Average ratio for stab. samples | |
Walker (2004) | Varied | Prismatic | Room | > 70 | 28 | 0 | HB 195 | Oven dry | 24 h immersion | 0.36 | ||
Guettala et al. (2006) | 100 | 100 | 200 | Prismatic | 20 | > 70 | 27 | 0 | AFNOR XP P13-901 | n/a | 24 h immersion | 0.67 |
Krisnaiah and Suryanarayana Reddy (2008) | 144 | 305 | 100 | Prismatic | Room | Room | 28 | 0 | n/a | Air dry | 48 h immersion | 0.20 |
Reddy and Kumar (2011) | 150 | 150 | 300 | Prismatic | Room | Room | 28 | 28 | n/a | Air dry | Saturated | 0.46 |
Alavéz-Ramírez et al. (2012) | 150 | 300 | 120 | Prismatic | Room | 90 | 0–28 | 3–90 | n/a | Air dry | 24 h immersion | 0.42 |
Kariyawasam and Jayasinghe (2016) | 240 | 240 | 140 | Prismatic | n/a | n/a | 28 | 0 | SLS 1382 | n/a | 24 h immersion | 0.54 |
Eires et al. (2017) | 50 | 50 | 55 | Cylindrical | n/a | n/a | 56 | 0 | ASTM D1633-00 | n/a | Saturated | 0.16 |
3.6.1 Wet Strength Tests by Walker in Bath, UK
3.6.2 Wet Strength Tests by Guettala et al. in Biskra, Algeria
3.6.3 Wet Strength Tests by Krisnaiah & Suryanarayana Reddy in Anantapur, India
3.6.4 Wet Strength Tests by Reddy & Kumar in Bangalore, India
3.6.5 Wet Strength Tests by Alavéz-Ramírez et al. in Oaxaca, Mexico
3.6.6 Wet Strength Tests by Kariyawasam & Jayasinghe in Moratuwa, Sri Lanka
3.6.7 Wet Strength Tests by Eires et al. in Braga, Portugal
4 Outdoor Experiments
4.1 Outdoor Testing of Laboratory Samples
4.1.1 Outdoor Tests in Sydney, Australia
4.1.2 Experiments in Lima, Peru
4.1.3 Experiments in Pamplona, Spain
4.2 Outdoor Testing of Wall Samples
4.2.1 Experiments in Biskra, Algeria
4.2.2 Experimental Site Near Grenoble, France
4.2.3 Experiments in Scotland, United Kingdom (Morton and Little 2015)
4.2.4 Measurements in Fujian Province, China
5 Discussion
5.1 Remarks on the Assessment Methods
5.1.1 Validity of the Standardized Test Methods
5.1.2 Problematic Variance in Test Parameters Among Authors
6 Remarks on the Costs of Stabilization
7 Conclusions
-
In spite of the difficulty in comparing the results of research and experience of practice, the data collected reinforce that the durability performance of stabilized earth constructions is adequate for widespread use.
-
Durability test parameters of sample size, pre-test moisture conditions and measurement methods should be incorporated into the relevant standards. Earth building practice worldwide would benefit from a unified assessment system, that can take into account these parameters.
-
A long awaited validation of durability assessment methods should be done:
- Either by developing a new test method that reliably simulates in-service conditions and its parameters are adaptable to different climates,
- Or by defining a numerical relationship between the results of existing test and in-service conditions, that is capable of taking into account specific climate characteristics.
-
An investigation of alternative stabilizers with low environmental impact is needed, mostly regarding their weathering due to climatic factors.
-
Assessment of existing strategies aiming to provide durability for earth constructions other than stabilization (i.e. renders, coatings, whitewashes, roof overhangs, structural inserts) is needed, that quantifies at least the relative performance of these approaches.
-
The erosion mechanisms and the durability performance of unstabilized earth materials merits a comprehensive investigation.