Fracture parameters formulation for single edge notched AS4 stitched warp-knit fabric composite plate

The three-dimensional problem of the fracture for the single edge notched tension plate (SENT) of orthotropic material is considered in this paper. The finite element solution is used to evaluate the singular and non-singular terms of the William series, i.e. Stress intensity factor (SIF) and T-stresses namely T11, T13 and T33. Based on the obtained numerical results, a fitting procedure is performed in order to propose analytical formulations giving the fracture parameters near the crack tip. The obtained results are in good agreement with the finite elements calculation and other literature results

Fracture parameters formulation for single edge notched AS4 stitched warp-knit fabric composite plate

The three-dimensional problem of the fracture for the single edge notched tension plate (SENT) of orthotropic material is considered in this paper. The finite element solution is used to evaluate the singular and non-singular terms of the William series, i.e. Stress intensity factor (SIF) and T-stresses namely T11, T13 and T33. Based on the obtained numerical results, a fitting procedure is performed in order to propose analytical formulations giving the fracture parameters near the crack tip. The obtained results are in good agreement with the finite elements calculation and other literature results

Fracture parameters formulation for single edge notched AS4 stitched warp-knit fabric composite plate

The three-dimensional problem of the fracture for the single edge notched tension plate (SENT) of orthotropic material is considered in this paper. The finite element solution is used to evaluate the singular and non-singular terms of the William series, i.e. Stress intensity factor (SIF) and T-stresses namely T11, T13 and T33. Based on the obtained numerical results, a fitting procedure is performed in order to propose analytical formulations giving the fracture parameters near the crack tip. The obtained results are in good agreement with the finite elements calculation and other literature results

Numerical Analysis of Plate Thickness Effect on Residual Stress Distribution around a Cold Expanded Hole

The process of cold expansion creates compressive stresses around the mounting hole, which can help to reduce stress concentrations during the loading of a structure. A numerical simulation using the finite element method was conducted to analyse the effect of cold expansion on perforated plates of different thicknesses. The simulation considered the thickness of the plate and the tapered mandrel and examined the induced residual stresses. The results showed that the magnitude of the circumferential residual stresses varied depending on the thickness of the plate and that the extent of the zone of compressive stresses was strongly affected by the plate thickness. These findings are particularly relevant to the optimisation of the cold expansion process, as the optimal parameters for a particular plate thickness may not be optimal for some other thickness. Therefore, the results of this study can guide the optimisation of the cold expansion process for different plate thicknesses

Elaboration of an Analytical Formula for the Calculation of the Surface Temperature

Pavement structures are sometimes subject to repeated dimensional variations of thermal origin generating mechanical stresses that may be detrimental to their durability. Among the most frequently observed degradations, by these stress, are the transverse cracks whose frequency, depth, and variable openings reduce the ride comfort. In this context, where such solicitations are preponderant and the strong variation is noticed on the surface, an analytical approach for calculating the surface temperature of a flexible pavement has been proposed. This approach is able to deal with the transient thermal problem including the phenomenon of ambient temperature and the influx of solar flux specifically for arid regions where the sky is often clear. This approach is adopted because it proposes a simplified calculation of the surface temperature. The model was built on a database measured on the experimental pavement of the laboratory of Egletons GEMH (France), using the calculation code Eureqa formulate. Although neglected in the domain's literature, the meteorological parameters (air temperature and solar flux) are taken into consideration in the analytic function because they give good prediction. The model has practical meanings to predicting the maximum, minimum, and amplitude of the pavement surface temperature. Hence, a good surface temperature assessment provides a key factor for further thermal cracking modeling

Fracture parameters formulation for single edge notched AS4 stitched warp-knit fabric composite plate

The three-dimensional problem of the fracture for the single edge notched tension plate (SENT) of orthotropic material is considered in this paper. The finite element solution is used to evaluate the singular and non-singular terms of the William series, i.e. Stress intensity factor (SIF) and T-stresses namely T11, T13 and T33. Based on the obtained numerical results, a fitting procedure is performed in order to propose analytical formulations giving the fracture parameters near the crack tip. The obtained results are in good agreement with the finite elements calculation and other literature results

Fuzzy Analytical Hierarchy Processes for Damage State Assessment of Arch Masonry Bridge

The present work proposes a fuzzy analytical hierarchy approach for decision making in the maintenance programming of masonry arch bridges. As a practical case, we propose to classify the degradation state of the Mohammadia masonry bridge. A large number of criteria and sub-criteria are combined to classify this type of bridges through visual inspections. The main criteria (level 1) considered in this work are the history of the bridge, the environmental conditions, the structural capacity and the professional involvement of the bridge. In addition, these criteria are subdivided into several sub-criteria (level 2) which are, in turn, subdivided into sub-criteria (level 3). Considering these criteria and sub-criteria, weights Wiare calculated by fuzzy geometric mean method of Buckley. Subsequently, expert scores were assigned to calculate the overall score CS reflecting the degradation of the considered infrastructure. Thereafter, the masonry arch bridges are classified respecting the French IQOA scoring system using the overall scores value CS. The proposed classification method gave similar results provided by an expert’s study realized previously as part of a national patrimony preservation policy. The obtained results are in good agreement, which makes this method an effective scientific tool for decision-making in view of prioritization of the maintenance after systematic inspection of masonry bridges such as the bridge studied in this work. Doi: 10.28991/cej-2021-03091770 Full Text: PD

Using Tuff and Limestone Sand to Minimize Water Consumption of Pavement Construction in Arid Regions

Soil compaction is a significant parameter for road construction projects. Since materials and soil compaction play important roles in the stability and durability of roads. This study focuses on the importance of the problems related to water resources in arid regions, considering both the economy and the population in these areas. For this reason, the local materials in Bechar (Algeria) were used to enhance the road construction process. Hence, using the combination of tuff and limestone sand (LS) materials to minimize the amount of water for the road construction compaction is investigated. Different combinations, including 100% tuff, 80% tuff and 20% limestone sand, 70% tuff and 30% limestone sand, and 60% tuff and 40% limestone sand, were evaluated with the Proctor and California Bearing Ratio (CBR) tests. The test results showed that using 60% tuff and 40% limestone sand resulted in the minimum water content of 10.5% compared to other combinations of tuff and limestone sand of this study, and it will be beneficial in arid regions where there is a water shortage. Three different percentages of lime (1%,2%, and 3%) were also added to the optimum mixture. However, the results showed that adding this material has no significant mechanical effects