Soil desiccation cracks and crack networks significantly influence the mechanical properties of soils. Accurate modeling and prediction of crack development are essential for both laboratory research and practical applications in geotechnical engineering and environmental science. In this study, a Desiccation Crack Simulation Program (DCSP) was developed on the MATLAB platform to simulate the evolution of soil desiccation cracks. Based on comprehensive statistical analyses of crack network images from previous studies and detailed observations of crack propagation, we propose a stochastic crack network generation model informed by geometric parameters and crack development processes. The model encompasses five key steps: (1) selection of crack initiation points, (2) crack propagation and intersection, (3) termination of crack growth, (4) secondary crack generation, and (5) final network formation. Key parameters include crack step size, randomized propagation direction, number of initial development points, and crack attraction distance. The DCSP enables both the rapid generation of random crack networks and the prediction of partially developed networks. The program was validated using two soil types, Xiashu soil and Pukou soil, demonstrating its effectiveness in simulating crack evolution. Prediction accuracy improves as crack network develops, highlighting the model's potential for predicting soil desiccation crack patterns.

The presence of desiccation cracks can affect rainfall-induced slope stability through both hydraulic and mechanical ways. Despite the valuable insights gained from physical tests in literature, there still lacks understanding how crack characteristics impact water flow dynamics and slope stability, especially considering the coexistence of vegetation. In this study, new analytical solutions were derived for calculating pore-water pressure and slope stability for an infinite unsaturated slope with cracks and vegetation. Both enhanced infiltration from water-filled cracks and water uptake by plant roots are considered. Using the newly developed solutions, two series of parametric analyses were carried out to improve understanding of the factors affecting crack water infiltration and hence the stability of vegetated slope. The calculated results show that slope failure at shallow depths is governed by the surface crack ratio, whereas deeper failures typically occur with greater crack depths. The surface crack ratio primarily influences the hydraulic response at shallow depths not exceeding 1.5 m, hence affecting the factor of safety for slip surfaces within the crack zone. Moreover, increasing the crack-to-root depth ratio from 0.5 to 1.5 results in a 25% reduction in suction at 1.5 m, threatening slope safety in deeper depth after 10-year rainfall.

This article evaluates the long-term wet-dry durability of lime, fly ash, and lime-fly ash slurry injection stabilization of expansive soil in the desiccated state. To achieve this objective, the expansive soil was compacted in large cylindrical test moulds and desiccated after making a central hole for slurry injection. Subsequently, the lime slurry/ fly ash slurry/ lime-fly ash slurry, prepared with the predetermined water-binder ratio, was injected into the desiccated expansive soil and cured for 28 days. The test results of lime and lime-fly ash slurry injected soils showed that there is improvement during the first wetting. However, at the end of four wet-dry cycles, the volumetric deformations of lime- and lime-fly ash slurry-treated soils increased to 10.6% and 13.6%, respectively, which are much lower than the volumetric deformation of untreated soil (30.7%). Additional analyses were also conducted to trace the growth of desiccation cracks of both untreated and treated soils. At the end of the third drying cycle, the total percentage of the cracks (surface cracks + annular gap) in lime slurry- and lime-fly ash slurry-treated soils reduced to 1.18% and 5.37% from the untreated soil value of 31.9%. The findings of the present study underline the positive impact of using lime, and lime in conjunction with fly ash for controlling the volume change behaviour of expansive soils. Furthermore, combination of lime and fly ash significantly reduces the consumption of lime, leading to sustainability in geotechnical practices.

In municipal solid waste landfills (MSWL), the center and peripheral regions of the basal compacted clay liner (CCL) often experience steady elevated temperatures due to waste biodegradation and cyclic temperatures similar to the seasonal atmospheric temperature patterns, respectively. In the present study, the negative effects of cyclic elevated temperatures on the desiccation behaviour of a MSWL basal CCL was examined by subjecting CCL samples to multiple wet-dry cycles with different drying temperatures. It was observed that the extent of desiccation cracking experienced by the CCL rose as the drying temperature and number of wet-dry cycles increased. The present study also assessed the effect of different thermoplastic cooling pipes on the reduction of temperature rise and desiccation experienced by CCLs exposed to constant elevated temperatures (CETs). It was observed that the introduction of thermoplastic cooling pipes led to a significant attenuation of the final temperature (FT) and desiccation magnitude along the CCL depth in the face of all applied CETs, irrespective of the cooling pipe material employed. A comprehensively analysis of the final temperature distributions within the entire CCL, coolant and sand layer surrounding the cooling pipe was also carried out via the conduction of a numerical simulation. Overall, the present study revealed the adverse effects imposed by cyclic elevated temperatures on a CCL and the potential that thermoplastic cooling pipes possess to successfully reduce the temperature rise and desiccation experienced by a CCL in the face of different CETs.

Soil desiccation cracking, a natural phenomenon involving the complex interaction of multi-physical fields, significantly weakens the mechanical and hydraulic properties of soil, potentially leading to natural hazards. This study proposes a coupled thermo-hygro-mechanical peridynamic (PD) model to investigate the mechanical responses and fracture behaviors in saturated soils due to moisture evaporation and heat transfer. Specifically, the temperature-dependent moisture diffusion and moisture-dependent heat conduction equations are nonlocally reformulated using peridynamic differential operators (PDDO). The constitutive model incorporates the spatial attenuation of nonlocal interactions and the effects of moisture and temperature in the bond-based peridynamic framework. Utilizing a hybrid explicit-implicit solution strategy, the model can effectively capture soil strip detachment, cracking, and curling. The model is also employed to explore moisture transmission mechanisms, evaluate the effects of temperature and thickness on crack morphology, and reveal the relationship between stress, strain evolution, and crack propagation. Furthermore, the model incorporates the reference evapotranspiration formula, which can account for environmental factors such as solar radiation, ambient temperature, relative humidity, and wind speed. Therefore, this expands the scope of model applicability and enables the simulation of soil desiccation cracking under natural conditions.

Desiccation crack patterns are commonly observed in natural and engineered soils and provides preferential pathways for moisture infiltrating into the soil. Cracks occur easily in soil when moisture is lost due to desiccation. Crack formation and development are closely related to moisture content and have a marked impact on the soil deformation characteristics and hydraulic properties. However, the critical moisture content below which desiccation cracks appear in the soil is usually determined by experiment because there is a lack of research on theoretical calculation models. Therefore, a theoretical calculation model is proposed to calculate the critical moisture content, and a parameter, lambda\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\lambda$$\end{document}, based on the following relationships: between soil grain size and suction, between suction and tensile strength, and between soil cracking and tensile strength. The critical moisture content values of different grain compositions were calculated and compared with laboratory experiments of desiccation crack. The critical moisture content of the granite residual soil is between 20% (50% liquid limit) and 30% (75% liquid limit). The presented model provides a means to estimate the critical moisture content of crack formation from soil desiccation using basic soil properties. This method can estimate the characteristics of soil desiccation cracks under extreme weather condition.

Dry season droughts may increasingly threaten Mediterranean forests under climate change. While plants employ three desiccation avoidance strategies to avoid or delay dehydration damage, including reduced water loss, enhanced tissue water storage, and improved root water access, resource allocation competition may lead to trade-offs among these strategies that are not yet fully understood. We investigated six Mediterranean woody species by analysing: (1) twig hydraulic capacitance (0.32 - 2.81 mmol m(-2) MPa-1) representing tissue water storage capacity; (2) twig residual conductance (g(res)) at 25 degrees C (1.23 -7.73 mmol m(-2) s(-1)) reflecting water loss rate; and predawn water potential (Psi(PD)) and its difference from midday water potential (triangle Psi) at the end of the dry season as root water access indicators. Significant trade-offs in plant desiccation avoidance strategies were observed as g(res) positively correlated with triangle Psi (R-2 = 0.78, P = 0.02) and twig hydraulic capacitance negatively correlated with Psi(PD) (R-2 = 0.68, P = 0.04). Consequently, species with greater root water access exhibited lower tissue water storage capacity and higher g(res), potentially increasing mortality risk when soil moisture becames limiting. By inverting a plant desiccation model, we also demonstrated that minimum survival-required hydraulic capacitance and a novel risk index were both positively correlated with Psi(PD), consistent with historical mortality records. Additionally, despite temperature-dependent g(res) patterns which revealed species-specific responses, elevated temperatures amplified the risk index for all species.

This study investigates the role of polypropylene fibers (PFs) in mitigating the combined effects of wet-dry (W-D) cycles and vibration event (VE), such as earthquake or machine vibrations, on the desiccation cracking and mechanical behavior of clay through model tests. A comprehensive experimental program was conducted using compacted clayey soil specimens, treated with various PF percentages (i.e., 0.2 %, 0.4 %, 0.6 %, and 0.8 %) and untreated (i.e., 0 % PF). These specimens were subjected to multiple W-D cycles, with their behavior documented through cinematography. Desiccation cracking and mechanical responses were evaluated after each W-D cycle and subsequent VE. Results indicated that surface cracking, quantified by morphology and crack parameters i.e., crack surface ratio (Rsc), total crack length (Ltc), and crack line density (Dcl), increased with progressive W-D cycles. Higher PF content in soil significantly reduced desiccation cracking across all W-D phases, attributable to the enhanced tensile strength and stress mitigation provided by the fibers. Following VE, surface crack and fragmentation visibility decreased due to the shaking effects, as indicated by reductions in Rsc and Dcl. However, Ltc increased slightly, suggesting either crack persistence or lengthening. Higher PF content resulted in a more substantial reduction in Rsc and Dcl and a reduced increase in Ltc after VE. W-D cycles led to increased cone index (CI) values, reflecting enhanced compactness due to shrinkage which enhances with PF content showing improved soil resistance to loading. Meanwhile, VE reduced CI values following W-D cycles, particularly in nearsurface layers, PF content mitigates this reduction, demonstrating that PF contributes to a more stable soil matrix. Also, PF content decreased the soil deformation under W-D cycles and subsequent VE.

Climate-induced desiccation cracks exhibit a hysteresis behavior, referred to as crack dynamic hysteresis (CDH), where they display different geometric characteristics during the drying and wetting phases at constant soil water content. This phenomenon has a complex effect on slope stability, an aspect often overlooked in analytical and numerical methods. In this study, we conducted experimental and numerical analyses to provide new insights into the effects of the CDH on slope stability. A series of laboratory experiments on desiccation cracking under drying-wetting cycles were performed. The testing results were used to develop and validate an extended dynamic dual-permeability model. The proposed model was integrated into a set of slope stability analyses using the finite element method. The numerical model results show that CDH causes greater fluctuations in crack dynamics and increases soil water retention under drying-wetting cycles. Neglecting this phenomenon leads to underestimation of slope stability during dry conditions and overestimation during wet conditions, with these discrepancies becoming more pronounced as the cycles progress. Furthermore, CDH changes the mechanical properties of soil, transitioning relatively stable zones to regions prone to localized instability. These unstable zones present significant challenges for accurately analyzing and managing slopes with cracked soil layers. Monitoring groundwater fluctuations and local crack development after heavy rainfall events is essential for mitigating localized slope collapses.

This study evaluates the utilization of rice straw as a reinforcement material in dredged slurry, focusing on sustainable waste-to-waste treatment practices. Unconfined compressive strength (UCS) tests were conducted on slurries with varying straw contents and sizes, including samples pretreated via pure water immersion. The study also analyzed the desiccation behavior of straw-reinforced slurry, examining parameters such as crack initiation time, maximum crack width, surface crack ratio, and failure morphology. Results indicate that straw fiber degradation within the first 72 h of aqueous pretreatment impacts the mechanical properties and structural integrity of the reinforced slurry. The introduction of straw alters the slurry's failure mode from brittle to plastic, enhancing ductility and residual strength. Optimal reinforcement occurred with a 0.5 % straw content, pretreated for 24 h, showing significant improvements in UCS and stiffness. Additionally, straw content between 3 % and 5 % optimally reduces cracking, with straw sizes of 0.6-1.0 mm providing effective crack control without disrupting the soil matrix. These findings suggest that straw can significantly enhance both the strength and dewatering efficiency of dredged slurry, offering practical implications for geotechnical applications in construction and landfill settings.