Ultimate Crack Research Articles

FLEXURAL PERFORMANCE OF REINFORCED CONCRETE BEAMS RETROFITTED USING FERROCEMENT WIRE MESH

Introduction: Ferrocement is a low-cost material that can be utilized as a replacement for expensive fiber-reinforced polymer (FRP), which is generally used for retrofitting structural and non-structural reinforced concrete members. The objective of this paper is to investigate the effectiveness of wire mesh in the retrofitting of flexural members such as reinforced concrete beams. It also investigated the flexural capacity of the beams, which are reinforced with wire mesh as a partial or complete replacement of regular rebar. The orientations and various forms of the wire mesh within the beam section are taken into consideration. The finite element method is used to model and analyze the beams. The structural performance of the studied beams, including the load-deflection relationship, first cracked and ultimate cracked loads, crack patterns, and flexural stress, were evaluated using the finite element method. The finite element model of the beam which is reinforced with wire mesh has been verified with experimental results. The results show that beams retrofitted with ferrocement or beams in which rebar is replaced by wire mesh have superior flexural performance and low crack depth. The beams retrofitted with wire mesh have a high ultimate load-carrying capacity and ductility. The confinement of three-sided wire mesh improves the flexural performance of the beam. It is observed that flexural performance remains the same when the length of the wire mesh exceeds half of the span length.

Loading rate effects on mixed-mode I/II fracture envelope of epoxy resins with nonlinear behavior

The tangential stress contour (TSC) method in combination with the equivalent material concept (EMC) was used to predict the fracture load, fracture initiation angle, and fracture resistance of an epoxy resin with nonlinear and ductile behavior. In this analysis, both the loading rate and mode mixing effects were taken into account to obtain the fracture envelopes of the tested resin. Based on the considered approach, only a tensile test performed on dogbone specimens and a pure Mode I fracture toughness test using semi-circular bend (SCB) samples are required to predict the ultimate load and crack initiation angle of the resin at different mode mixities. According to this technique, the non-linear ductile behavior of the tested epoxy is simulated by a virtual brittle linear response, which greatly simplifies the problem. The predicted fracture envelope was validated by experimental results. A very good agreement between the prediction and the experimental data was obtained.

Effect of polyethylene terephthalate fibres on the structural performance of reinforced concrete beams with openings in the shear region

The provision of transverse openings in the shear region of beams to allow passage of services reduces the cracking and ultimate load capacities of the beams and increases deflection under the openings, especially when the size of the opening exceeds 25 % of the overall beam depth. Strengthening of the pre-planned opening regions by use of special steel reinforcements causes reinforcement congestion and difficulties in compaction, calling for alternative ways of strengthening beams with openings. In this study, concrete material was modified by the use of Polyethylene Terephthalate (PET) fibres produced from waste plastic bottles to improve the tensile properties and hence reduce the cracking around the openings and improve the overall performance of the beams. To evaluate the performance of PET fibres in beams with openings, eight (8) reinforced concrete beams with and without fibres of dimensions (150 × 250 × 2000 mm) were cast with varying opening sizes. The horizontal position of the openings was fixed at 300 mm from the support while the vertical position was maintained at the mid-depth of all beams. This performance was evaluated in terms of ultimate and first cracking loads, mid-span deflections, ductility, crack patterns and failure modes, and strain behavior. Test data showed that incorporating PET fibres in beams with openings resulted in a slight increase in ultimate load of 4.1 % and 5.82 % for 0.25 h and 0.35 h beam opening sizes respectively, beyond which the strength was reduced by 9.57 % for beams with 0.45 h opening size, where h was the overall depth of the beam. The first cracking loads increased by 44.12 %, 48.48 %, and 9.38 % for 0.25 h, 0.35 h, and 0.45 h opening sizes, respectively. In addition, a slight improvement in the ductility of PET fibre beams for all opening sizes was observed. The PET fibre beams exhibited a slight change in the mode of failure from dominant shear failure to combined shear and flexure failure characterized by multiple cracks in the flexure region with minimal spacing. An increase in the concrete compressive and tensile strains accompanied by a reduction in concrete and steel shear strains was observed because of the tension stiffening effects of the fibres. The incorporation of PET fibres, therefore, showed a slight improvement in the ultimate performance of beams with 0.25 h and 0.35 h opening size, with no improvement for the control beam and 0.45 h opening sized beam. However, a significant improvement in the serviceability performance for all PET reinforced beams was observed.

Influence of Infill on Reinforced Concrete Frame Resting on Slopes under Lateral Loading

When compared to traditional reinforced concrete constructions on level surfaces, buildings situated on hills with slopes require additional consideration, particularly when seismic loading is an important factor. In hilly slopes, the ground-level columns of structures have different heights due to the nature of the slope, which leads to a short column effect. This paper represents an experimental and analytical investigation of the behaviour of reinforced concrete frames and their response in sloped regions of hills, in which global retrofitting techniques were adopted by providing solid infill in the short column effect zone for the columns in the same storey of differentheights. Numerical analysis was conducted on how infill affected the short column effect under lateral cyclic loads. It was discovered that compared to bare reinforced concrete frames, masonry infill greatly increased the lateral load-carrying capacity by up to 50%. In the meantime, the frame’s ability to dissipate energy increased linearly. After infill was added to the frame with the short column effect, the reinforced concrete structure’s different reactions, including ultimate load displacement, crack pattern, energy dissipation, and energy absorption, were examined. With the addition of a solid infill, the reinforced concrete structure’s lateral strength and energy dissipation capacity were increased by 2.45 times. The damage development on the reinforced concrete frame with infill and the short column effect was less impacted by lateral stress than the reinforced concrete frame without infill.

Experimental investigations of flexural and shear behavior of continuous prestressed HSC beams under repeated loads

The results of an experimental study into the flexural and shear conduct of continuous two span unbonded posttensioned high strength concrete beams subjected to static and a limited number of repeated loading cycles are presented in this paper. The experimental program comprising testing and experimentation of four continuous unbonded posttensioned high strength beams with a total length (4300) mm. The main objective of this study was to see how the strength and serviceability of continuous prestressed concrete beams were affected by restricted repeated loading cycles. As a result, these beams were split into two similar groups. The first set consisted of two beams to study the flexural behavior. The second set consisted of two beams to study the shear behavior. For each set one tested under static loads and the second tested under repeated loads. They were subjected to two concentrated loads in the middle of each span loads up to destruction. It was determined that the repeated load ranged between 0.4 and 0.6 of the ultimate load generated by the static test. Immediately following the ten cycles, the load was withdrawn, and the beams were subjected to a monotonic static test until failure was achieved. Recorded the cracking and ultimate load capacity, midspan deflections, and crack widths. The experimental results explained that the ultimate flexural and shear strength for beams that are tested under repeated loads is a little reduced (1.7%) and (3.9%) comparing with the strength of the identical beams under monotonic static loading and increasing the ultimate deflection after ten cycles of repeated loading, decreased about (5.3%) and (15.1%) for flexural set and shear set, respectively.

Seismic in-plane displacement capacity of masonry barrel vaults: the role of constructive aspects

Historic masonry vaults are one of the most vulnerable elements with respect to the seismic action. Cracks are often detected after post-earthquake surveys. However, it is difficult to directly link the observed damage to causes. Different mechanisms can occur during an earthquake, such as in-plane horizontal shear distortion or longitudinal opening/closing of the abutments. These mechanisms are not necessarily associated to a specific crack pattern, since other factors are involved in the determination of the detected crack status. Among these factors, constructive aspects (such as the brick pattern) play a major role. This study aims at investigating the possible correlation between constructive aspects and the crack pattern in barrel vaults subjected to in-plane shear mechanism. Numerical simulations are carried out on an ideal circular vault with a rectangular base of dimensions 3.1 × 5.3 m, and rise of 1.175 m. Three brick patterns are considered: radial, diagonal and vertical. In order to investigate these aspects, a micro-modelling numerical approach has been adopted. Results are presented in terms of ultimate displacement capacity, collapse mechanisms and crack pattern charts.

Research on the Development and Joint Improvement of Ceramsite Lightweight High-Titanium Heavy Slag Concrete Precast Composite Slab

Despite the continuous improvement in the research and development of concrete precast composite slab technology, problems like easy cracks and excessive weight at the joints remain. In this study, high-titanium heavy slag was mixed with different kinds of ceramsite to prepare ceramsite lightweight high-titanium heavy slag concrete. The joint of the composite slab was optimized to develop a novel ceramsite lightweight high-titanium heavy slag concrete precast composite slab, hereinafter referred to as “CLHCPCS”. Two CLHCPCS and one ordinary concrete composite slab were prepared. This study analyzed the effects of new materials and improved joints on the flexural capacity and crack resistance of CLHCPCS. It concluded that the density of high-titanium heavy slag concrete with shale ceramsite decreased by 12.0%, and the density of high-titanium heavy slag concrete with fly ash ceramsite decreased by 10.6%. At a 30% dosage of fly ash ceramsite, the compressive strength and splitting tensile strength of concrete reached the maximum. At a 20% dosage of shale ceramsite, the mechanical properties were optimal. Finally, fly ash ceramsite was selected as part coarse aggregate of CLHCPCS. CLHCPCS 1 and 2 demonstrated superior ultimate bearing capacity and crack resistance than ordinary concrete composite slab DBS1, with its ultimate bending capacity test value higher than the average value of ordinary concrete composite slab. ANSYS established the joint model of CLHCPCS for a bending simulation test. The stress and strain distribution of the model and the ultimate bending capacity under the plastic line method were obtained, consistent with theory and experimental analysis results.

The effect of Corroded Longitudinal Steel Bars on Flexural Behavior of Reinforced Concrete Beams

This study aims to examine the relationship between the corrosion rate of longitudinal tensile steel bars and the maximum flexural strength of reinforced concrete RC beams. The study's methodology is designed to show the structural behavior of corroded and non-corroded RC beams, such as ultimate load, deflection, stiffness, crack patterns, and failure mode. Three rectangular beams were cast with dimensions (150× 200 ×1200) mm, and all specimens have the same amount of longitudinal and transverse reinforcement and the same concrete strength. The major parameter is the theoretical mass loss level due to corrosion (0, 10, 15) %. Electrochemical technique was used to accelerate the corrosion in the longitudinal tensile bars. All RC beams were tested under four-point monotonic loading. The test results confirm that the cracking load in corroded beams decreased by 25% comparative to the non- corroded beam. The increase of the percent of corrosion experimental mass loss by 8.25 and 14.15 % decreased the ultimate load by about 14 % and 27%, respectively. This reduction coincided with the decrease in deflection values in mid-span for the ultimate load, which decreased by 53.9% and 46.3%. However, the flexural stiffness was reduced by 13.4 and 15.6% for corroded beams with mass loss (8.25 and 14.15), respectively, compared to the control beam (non-corroded RC beam).

Improving bond strength of recycled coarse aggregate concrete using chopped basalt fibers

This paper investigates theoretically and experimentally the influence of using basalt fiber (BF) on bond strength of recycled coarse aggregate (RCA) concrete. The natural aggregate (NA) was replaced by RCA with 20 %, 40 %, 60 %, 80 %, and 100 %. BF was added with three different percentages. Ninety concrete cubes were tested under pull-out loading to failure using steel bar diameters 12, 14, and 18 mm. The behavior of specimens was analyzed by recording ultimate tensile loads and crack patterns. The experimental bond strengths were correlated with the theoretical strengths calculated using equations of different international codes in addition to existing models by previous researchers. The experimental results revealed that the bond strength improved when the RCA levels and BF contents increased. The 80 % RCA and 1.5 % BF showed the highest increase. Also the bond strength decreased as the bar diameter increased. The mode of failure for all specimens in this study was splitting failure and BF caused ductile failure. The experimental bond strengths were higher than the calculated theoretical strengths. Thus, theoretical equations can be used for determining bond strength of RCA.

Silica Masterbatches Produced with Liquid Phase Mixing; Part III. Quasi-Static Stress-Softening

The stress-softening effect of rubber-like materials is a phenomenon such that the stress required to attain a given elongation is less during the second cycle of deformation. In practice, stress-softening effects are used as a quantitative measure of strain energy loss. Both rubber reinforcement by fillers and the failure properties of vulcanizates, such as ultimate strength, tearing, cracking, abrasion, and fatigue, are closely related to the processes of energy dissipation during deformation. This paper reports the results of our research on the quasi-static stress-softening effect of vulcanizates of solution-polymerized styrene butadiene rubber (SSBR)/cis-polybutadiene rubber (BR)/silica masterbatches named Eco-Visco-Elastomer composite (EVEC) produced by a continuous liquid phase mixing, taking dry-mixed silica- and carbon black-filled vulcanizates as references. With this liquid phase mixing, the silanization efficiency of EVEC was greatly improved. Compared with the conventional silica filled vulcanizates, the stress softening effect of EVEC was significantly lower at low strain and rose more rapidly with increasing strain, which could be explained by the effects of filler agglomeration and polymer-filler interaction. The less energy dissipation at low strain is mainly due to fewer filler agglomerates, whereas at high strain, for EVEC, it is attributed to more rupture of polymer crosslinks and polymer chains in the matrix with increasing extension, due to higher polymer-filler interaction resulting in less slippage of polymer chains along the filler surfaces.

UPGRADING THE PERFORMANCE OF DEFECTED BEAMS BY USING SLURRY INFILTRATION FIBER-REINFORCED CONCRETE AS A STRENGTHENING SOLUTION

One of the ways to increase the service life or upgrade the concrete buildings is by strengthening and repairing techniques. There are many methods of strengthening, such as using slurry infiltration fiber-reinforced concrete (SIFCON). This study cast eight normal reinforced concrete beams of 100 × 150 × 1000 mm. Seven are pre-loaded to 60% of their ultimate load, and the eighth is loaded to its ultimate load. Six beams are repaired with fresh and precast SIFCON layers in different configurations (bottom and jacketing). However, for comparison reasons, two beams are repaired with carbon fiber-reinforced polymer (CFRP) and steel fiber concrete. All beams are tested under a two-point flexural load. The parameters (ultimate load, ductility, toughness, stiffness, crack width, residual strength, and mode of failure) are investigated. The purpose of the study is to use a compatible cement-based material with new techniques for strengthening or repairing concrete members. The results showed that the new techniques significantly improved the behavior of the pre-loaded beams, and SIFCON layers (fresh or precast) could compensate for the failure in the steel reinforcement and be used as external reinforcement.

RETRACTED: Effect of CaCO3 whiskers on tensile properties of ultra-high-performance engineered cementitious composites

Ultra-high-performance engineered cementitious composite (UHP-ECC) is expected to become an ideal construction material for its superior mechanical properties. However, the high cost of UHP-ECC, especially the use of expensive synthetic fibers, limiting its extensive engineering application. To address this, cheap calcium carbonate (CaCO3) whiskers were utilized to partially replace polyethylene (PE) fibers. The various volume fractions of PE fibers and CaCO3 whiskers were adapted to possess different tensile properties (ultimate tensile stress, strain capacity, crack number, and strain energy). The results indicated that the decrease in PE fiber content from 2% to 1.5% significantly deteriorated tensile properties of UHP-ECC (the decrease of 24.95% in tensile strength and 49.47% in strain capacity). However, the partial replacement of PE fibers by CaCO3 whiskers could effectively mitigate the performance degradation and improve the stable multiple cracking behavior. Especially, the tensile ductility of UHP-ECC with a combination of 1.75% PE fibers and 0.5% CaCO3 whiskers was 45.19% higher than that of UHP-ECC with mono 1.75% PE fibers, and also 102.5% higher than that of control group (2% PE fibers). Scanning electron microscopy images confirmed the synergistic effect of PE fibers and CaCO3 whiskers at the microscopic level. In according with micromechanics, the addition of CaCO3 whiskers could effectively improve the complementary energy of UHP-ECC by micro cracking arresting, which increased the pseudo strain hardening values and thus leading to the enhancement in tensile ductility of UHP-ECC. In addition, the hybrid fiber reinforcing index (RIv) had a positive correlation with the tensile properties of UHP-ECC. Therefore, a semi-empirical formula based on RIv could be adopted for the property prediction of UHP-ECC with different combination of PE fibers and CaCO3 whiskers.

Experimental investigation of CIP and PC beam-to-CECFST column joints with simple connection details under lateral cyclic loading

Due to the excellent structural performance of Concrete-encased concrete-filled steel tube (CECFST) columns, they have been applied in real practice for several years. In addition, precast technology can be utilised in the construction of CECFST composite structures to further improve productivity. To investigate the behaviour of precast concrete (PC) and cast-in-place (CIP) beam-to-CECFST column joints, a total of 6 joint specimens, including 4 PC and 2 CIP specimens, were thus experimentally studied under lateral cyclic loading. In this paper, the main studied parameters included connection details, construction methods and existence of column axial load. The ultimate strength, failure mode, crack patterns and hysteretic performance of each specimen were analysed in detail. According to the test results, the performance of CIP and PC joint specimens were discussed in the aspect of energy dissipation, ductility and damping coefficients, strength and rigidity degradations. It was found that the PC specimens exhibited comparable cyclic behaviour to the CIP specimens in regards to the maximum strength, hysteretic performance and failure mode. Moreover, based on the measured shear strains, contributions of joint shear resistance from steel tube, inner and outer concrete were quantitatively investigated. Thereafter, the development of shear stress in the outer concrete was compared with the nominal concrete shear strengths from American and European design provisions.

The influence of PVA content on the flexural behavior of engineered cementitious composite using local materials

Engineered cementitious composite (ECC) creates many potential civil engineering applications due to its outstanding ultimate tensile strain capacity (normally exceeding 2%) compared to conventional concrete and fiber reinforced concrete. The high tensile ductility of ECC is mainly influenced by fiber characteristics. In this study, the effect of polyvinyl alcohol (PVA) content, i.e. from 2 to 6% by vol. of concrete, on the flexural behavior of ECC with a desired compressive strength of over 60 MPa, in which fly ash and silica fume were selected as supplementary cementitious materials. The experimental results show that the addition of PVA fiber gives little influence on compressive strength but can significantly affect the flexural behavior of ECC. Besides the optimum fiber content, the ratio between the ultimate and first crack strength of ECC was also evaluated.

Flexural behavior of ultra-high-performance concrete beams with various types of rebar

This study describes the behavior of ultra-high-performance-concrete (UHPC) beams with GFRP and steel reinforcements. The experimental results were presented and the influences of parameters, including reinforcement ratio and longitudinal rebar type on the flexural performance of the UHPC beams, were investigated and discussed. The test results show that increasing the amount of GFRP reinforcements results in the enhancement of their flexural behavior, including load bearing capacity, post-cracking stiffness, and deformation capacity. The ductility decreased when greater GFRP reinforcements were designed. Compared to steel reinforced beams, the UHPC beams with GFRP rebars performed more rapid stiffness degradation and crack width development. The use of steel reinforcements by replacing GFRP rebars in the beam contributed to the improvement of some flexural behavior, including cracking load, post-cracking behavior, displacement, and ductility. The bond strength and ability to retard crack development between GFRP rebars and UHPC are worse than that between steel rebars and UHPC. The design equations recommended by the design codes showed that existing codes may over-estimate the ultimate flexural capacity and crack width of the GFRP-UHPC beams. The increasement of GFRP reinforcement ratio will cause the calculated displacement based on the codes less than that obtained from experiment.

Flexural behavior of HSC beams reinforced by hybrid GFRP bars with steel wires

This study offers the flexural performance of HSC beams of 60 MPa compressive strength with locally manufactured hybrid-GFRP (HGFRP) bars with steel wires in experimental and analytical manners. Both investigations were done to explore the influence of using HGFRP bars with various reinforcement ratios for these beams as a new ductile hybrid reinforcement. So, six beams of dimension 150X300X1700 mm were tested in the National Building Research Center-Cairo, Egypt till failure. The main variables were the reinforcement types (steel, GFRP, Hybrid GFRP). The ultimate loads, mid-span deflections, and reinforcement bars strains of the tested beams were documented. Nonlinear analysis was assembled to validate the flexural performance of beams using ANSYS program, in terms of ultimate load, stains, crack pattern and load deflection curves. Numerical investigations good agreement with experimental ones in terms of ultimate loads and deflections, cracking patterns, and the behavior of load deflection.

Experimental Analysis of Recycled Aggregate Concrete Beams and Correction Formulas for the Crack Resistance Calculation

This paper studies the similarities and the differences between natural aggregate concrete (NAC) beams and recycled aggregate concrete (RAC) beams in terms of concrete material properties, bearing capacity, and crack resistance and further proposes correction formulas for cracking moment calculation of RAC beams that consider different recycled aggregate substitution ratios. First, the basic mechanical properties (e.g., cube compressive strength, axial compressive strength, and elastic modulus) of RAC blocks were tested; second, comparative bending tests of RAC beams and natural aggregate concrete beams were conducted, in order to obtain the cracking moments, yield bending moments, ultimate bending moments, mid-span deflections and crack development forms; finally, numerical simulations were performed to investigate the cracking performances of RAC beams. Through analyzing the experimental results, it is found that the crack development pattern of RAC beams resembles that of natural aggregate concrete beams, while the cracking performance of RAC beams significantly deviates from that of NAC beams. Finally, the correction formulas for the cracking moment calculation of RAC beams are proposed based on the numerical simulation results and verified by data from other researchers, which can be regarded as a correction for the cracking moment calculation formulas in the current code for RAC beams with respect to varied recycled concrete aggregate substitution ratios.

Experiment Program on Retrofitted Anchorage System under Impact Loads

This study aims to evaluate the strength and performance of retrofitted anchorage system in concrete under impact loads. A novel technique called “Post Installation of Supplementary Anchorage” (PISA) is introduced to retrofit five different configurations of rebar anchorage system used in concrete. The configurations of rebar are straight bar (A1), 90 degree bend (A2),180 degree hook (A3), single head (A4) and double head (A5) bars which was retrofitted by supplementary steel reinforcement. Direct tension pullout loads are applied on 60 anchorage specimens (each 30 of conventional and retrofitted) casted with M25 grade concrete. The boundaries of tested specimens were followed by strut-and-tie analogy. The rebar anchorage tested at 1.58, 1.52 impact factor using two different bars of 12mm and 16mm diameter respectively. The deterministic characteristics of test parameters are normal strength, bond strength, ductility, and slip of anchorage at ultimate load. The test variables are rebar configuration, size of anchored bar, and presence of supplementary steel. The results validated by nonlinear finite element based ANSYS modeling. A good agreement of results between experiment and model analysis was observed. Also a considerable improvement of nonlinear characteristics of retrofitted anchorage such as ultimate load (3%-6%), bond strength (1%-6%), ductility (3%-4%), concrete contribution (20%-32%), bar slip (8%-48%) and crack width (30%-42%) was obtained. This study promotes useful information to retrofit non-engineered anchorage system by PISA technique. Application of this technique may further extended to retrofit discrete regions of concrete elements such as bracket connection, corbel projection and beam-column joint subjected to impact loads.

Crack Propagation Assessment of Time-Dependent Concrete Degradation of Prestressed Concrete Sleepers

As prestressed concrete sleepers are continuously exposed to various environmental and loading conditions, it is increasingly crucial to analyse their current and future serviceability performance. In practice, the main cause of cracking in prestressed concrete sleepers is usually induced by impact loads. The most heavily influenced sections are the midspan and rail-seat area of sleepers. This paper investigates the effects of time-dependent concrete strength degradation on the capacity of prestressed concrete sleepers. The factors affecting concrete strength degradation are analysed in order to evaluate the crack behaviour of prestressed concrete sleepers. A finite element modelling approach is developed for prestressed concrete sleepers, which is used to assess the effects of structural behaviour in railway sleepers. The sleeper model has been calibrated and validated. This research firstly discusses time-dependent behaviour using load–crack length responses. It is shown that various cracking modes cause an overall increase in the maximum cracking length as prestressed concrete sleepers age. This paper demonstrates that initial cracking loads and ultimate crack lengths have significant change in first 20 years. After 40 years of service life, the crack resistance of prestressed concrete sleepers becomes very weak which is only 61.32% of the new sleeper. In long term, the initial cracking load keeps reducing, and the crack propagation rate becomes sharp. The presented methodology and results can greatly assist in decision-making for the repair or replacement of prestressed concrete sleepers and aid in the design of new prestressed concrete sleepers considering their future performance.

Modelling soil desiccation cracking by peridynamics

Understanding of desiccation-induced cracking in soil has improved over the last 20–30 years through experimental studies, but progress in predictive modelling of desiccation cracking has been limited. The heterogeneous structure of soils and the multi-physics nature of the phenomenon, involving emergence and propagation of discontinuities, make the mathematical description and analysis a challenging task. The authors present a non-local hydro-mechanical model for soil desiccation cracking capable of predicting crack initiation and growth. The model is based on peridynamics (PD) theory. Attempts to model soil desiccation cracking by PD are limited to a purely mechanical description of the process that involves calibration of the parameters. In contrast, the model presented in this paper describes soil desiccation cracking as a hydro-mechanical problem, where moisture flow and deformation are coupled. This allows for investigating and explaining the mechanisms controlling the initiation and propagation of discontinuities. The model is applied and tested against two sets of experimental data to explain the typical features of drying-induced cracking of clays. The validations use experimental parameters (Young's modulus, water retention characteristics) and avoid calibrations to test the accuracy of the model. The correlations between the shrinkage of soil clay, changes in displacement fields and crack growth are demonstrated. Crack initiation, propagation and ultimate crack patterns simulated by the model are found to be in very good agreement with experimental observations. The results show that the model can capture realistically key hydraulic, mechanical and geometry effects on clay desiccation cracking.