scholarly journals Effect of Axial Pressure on Lime-Treated Expansive Soil Subjected to Wetting and Drying Cycles

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Chuxuan Tang ◽  
Zheng Lu ◽  
Hailin Yao
Keyword(s):  
Resilient Modulus ◽  
Axial Strain ◽  
Expansive Soil ◽  
Axial Pressure ◽  
Wetting And Drying ◽  
Wetting And Drying Cycles ◽  
Subgrade Soil ◽  
Moisture Variation ◽  
The Impact ◽  
Properties Of Soil

The impact of seasonal moisture variation on subgrade soil, including lime-treated expansive soil, has been investigated in many studies. However, when performing wetting and drying cycles, the effect of stress, which decides the behavior and mechanical properties of soil, is usually ignored. In this paper, the effect of axial surcharge pressure on the deformation and resilient modulus of lime-treated expansive soil subjected to wetting and drying cycles was investigated. A self-made apparatus was chosen to apply axial surcharge pressure and precisely control the variation of moisture content. The lime-treated specimens were placed in the self-made apparatus and then subjected to wetting and drying cycles under three different surcharge pressures. The results show that the axial surcharge pressure has a significant influence on the development of axial strain and resilient modulus. In particular, larger surcharge pressure induces accumulate irreversible shrinkage, whereas lower surcharge pressure tends to lead to irreversible swelling. On the contrary, the larger surcharge pressure leads to higher resilient modulus of the tested specimen after wetting and drying cycles.

scholarly journals Influence of Wetting and Drying Cycles on Physical and Mechanical Behavior of Recycled Aggregate Concrete

Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5675
Author(s):  
Caroline S. Rangel ◽  
Mayara Amario ◽  
Marco Pepe ◽  
Enzo Martinelli ◽  
Romildo D. Toledo Filho
Keyword(s):  
Recycled Concrete ◽  
Recycled Aggregate Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Demolition Waste ◽  
Wetting And Drying ◽  
Aggregate Concrete ◽  
Wetting And Drying Cycles ◽  
The Impact

Recently, concerns have been rising about the impact of increasing the depletion of natural resources and the relevant generation of construction and demolition waste, on the environment and economy. Therefore, several efforts have been made to promote sustainable efficiency in the construction industry and the use of recycled aggregates derived from concrete debris for new concrete mixtures (leading to so-called recycled aggregate concrete, RAC) is one of the most promising solutions. Unfortunately, there are still gaps in knowledge regarding the durability performances of RAC. In this study, we investigate durability of structural RAC subjected to wet-dry cycles. We analyze the results of an experimental campaign aimed at evaluating the degradation process induced by wetting and drying cycles on the key physical and mechanical properties of normal- and high-strength concrete, produced with coarse recycled concrete aggregates (RCAs) of different sizes and origins. On the basis of the results we propose a degradation law for wetting and drying cycles, which explicitly makes a possible correlation between the initial concrete porosity, directly related to the specific properties of the RCAs and the resulting level of damage obtained in RAC samples.

scholarly journals Performance of driven battered mini-pile group against expansive soil induced ground movement

2020 ◽  
Vol 195 ◽  
pp. 01030
Author(s):  
Shirin Aminzadeh Bostani Taleshani ◽  
Robert Evans ◽  
Emad Gad ◽  
Mahdi Miri Disfani
Keyword(s):  
Field Trial ◽  
Structural Damage ◽  
Expansive Soils ◽  
Expansive Soil ◽  
Cost Effective ◽  
Pile Group ◽  
Ground Movement ◽  
Ground Movements ◽  
Moisture Variation ◽  
The Impact

Swell-shrink movement of expansive soils due to seasonal wetting and drying can cause differential ground movements. This movement can inflict substantial structural damage above foundation level to lightly loaded infrastructure. To reduce this movement, techniques have been employed to either (i) chemically restrain the soil’s reactivity, (ii) control the moisture variation within the ground, or (iii) engage a footing system that can limit the impact of the stresses generated by such differential ground movements. Recently, a new concrete-free footing system has been developed in Australia in an attempt to sufficiently resist such ground movements. This system is comprised of an adjustable steel plate attached to the ground by multiple thin steel (hollow) battered mini-piles. The technology shows promise as a low-impact, cost-effective, excavation and concrete-free, innovative alternative to traditional footing systems. It is also quick and easy to install without the use of bulky and expensive equipment. Early field trial results have indicated that this new footing system can combat against and significantly reduce the transfer of the swell-shrink ground movements to a structure. This paper will describe this new footing system and report on an experimental field trial to date, which will include measured ground movements, moisture content and soil suction results vs. depth, as well as the performance of this new driven battered mini-pile group footing system.

scholarly journals Changes in Water Infiltration after Simulated Wetting and Drying Periods in two Biochar Amendments

Soil Systems ◽  
2019 ◽  
Vol 3 (4) ◽  
pp. 63 ◽  
Author(s):  
Karolina Villagra-Mendoza ◽  
Rainer Horn
Keyword(s):  
Sandy Loam ◽  
Water Infiltration ◽  
Hydrological Response ◽  
Infiltration Capacity ◽  
Wetting And Drying ◽  
Wetting And Drying Cycles ◽  
Infiltration Models ◽  
Drying Conditions ◽  
The Impact ◽  
Infiltration Behavior

Biochar impacts soil-water related processes such as infiltration and contributes to the hydrological response of catchments. The aim of this work is to determine the impact of wetting and drying conditions on the infiltration behavior of two biochar amendments and to validate the performance of three infiltration models: Kostiakov, Horton, and Philips. Two materials, sand and a sandy loam, were mixed with 0%, 2.5%, and 5% (by dry wt.) mango wood biochar produced at a highest heating rate of 600 °C and with a particle size of <63 μm. A sequence of four wetting and drying cycles were simulated. In each cycle, infiltration was measured. We found that biochar addition decreased infiltration because the formation of narrower pores reduced infiltration capacity. The higher the biochar dosage, the more resilient the treatment became concerning the changes on the water infiltrated. Repetitive wetting and drying cycles resulted in a reconfiguration of structural pores affecting the transport of water and air. The infiltration models of Kostiakov and Horton could predict the infiltration dynamics in the amended materials, although they show some instabilities along the WD cycles.

scholarly journals Impact of wetting/drying cycles on the hydromechanical behaviour of a treated soil

2020 ◽  
Vol 195 ◽  
pp. 06008
Author(s):  
Olivier Cuisinier ◽  
Farimah Masrouri
Keyword(s):  
Hydraulic Conductivity ◽  
Wetting And Drying ◽  
Wetting And Drying Cycles ◽  
Positive Effects ◽  
Hydromechanical Behaviour ◽  
Special Concern ◽  
Major Alteration ◽  
Number Of Cycles ◽  
The Impact

The positive effects of lime or cement treatment could be altered by weathering in the very long term. In this context, the main purpose of this study is to examine the impact of wetting/drying cycles on the strength and the hydraulic conductivity of a compacted soil treated with lime and cement. Compacted specimens were cured for 90 days before being exposed up to twelve wetting and drying cycles. A special concern of the study was the experimental method to impose the wetting and drying cycles. Two protocols were employed: one relied on relative humidity control to dry the samples, while the other was based on oven drying. The impact of the cycles was quantified by comparing the performance of the samples exposed to the cycles to the performance of the unsolicited samples. The results showed that the cycles induced a major alteration of the strength of the samples, with both methods. This degradation is associated to a significant increase of the hydraulic conductivity of the samples with the number of cycles.

X‐ray tomography analysis of soil biopores structure under wetting and drying cycles

2021 ◽  
Author(s):  
Sougueh Cheik ◽  
Pascal Jouquet ◽  
Jean‐Luc Maeght ◽  
Yvan Capowiez ◽  
T.M. Tran ◽  
...  
Keyword(s):  
Wetting And Drying ◽  
X Ray ◽  
Wetting And Drying Cycles ◽  
Tomography Analysis

scholarly journals Impact of Organic Amendment with Alternate Wetting and Drying Irrigation on Rice Yield, Water Use Efficiency and Physicochemical Properties of Soil

Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1529
Author(s):  
Ahmad Numery Ashfaqul Haque ◽  
Md. Kamal Uddin ◽  
Muhammad Firdaus Sulaiman ◽  
Adibah Mohd Amin ◽  
Mahmud Hossain ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Water Use Efficiency ◽  
Water Use ◽  
Organic Amendment ◽  
Rice Yield ◽  
Organic Amendments ◽  
Irrigation Regime ◽  
Wetting And Drying ◽  
Use Efficiency ◽  
Properties Of Soil

A pot experiment was executed to investigate the impact of biochar and compost with water-saving irrigation on the rice yield, water use efficiency, and physicochemical properties of soil. Two irrigation regimes—namely alternate wetting and drying (AWD) and continuous flooding (CF)—and four types of organic amendments (OA)—namely rice husk biochar (RHB), oil palm empty fruit bunch biochar (EFBB), compost and a control—were applied to evaluate their effects. Under the AWD irrigation regime, the maximum grain was produced by RHB (241.12 g), whereas under the same organic amendments, both AWD and CF produced a similar grain yield. Under the same organic amendment, a significantly higher water use efficiency (WUE) was observed from the AWD irrigation with RHB (6.30 g L−1) and EFBB (5.80 g L−1). Within the same irrigation regime, soil pH, cation exchange capacity, total carbon, total nitrogen and available phosphorus were enhanced due to the incorporation of biochar and compost, while higher soil exchangeable potassium was observed under CF irrigation for all treatments. RHB and EFBB significantly reduced the soil bulk density (up to 20.70%) and increased porosity (up to 16.70%) under both irrigation regimes. The results imply that the use of biochar with AWD irrigation could enhance the nutrient uptake and physicochemical properties of soil and allow rice to produce a greater yield with less water consumption.

Sign in / Sign up

Export Citation Format

Share Document