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The paper deals with the analysis of the load-carrying capacity of a timber semi-rigid connection created from a system of two stands and a rung. The connection was made from glued laminated timber with metal mechanical dowel-type fasteners. Not only a common combination of bolts and dowels, but also fully threaded screws were used for the connection. The aim of the research and its motivation was to replace these commonly used fasteners with more modern ones, to shorten and simplify the assembly time, and to improve the load-carrying capacity of this type of connection. Each of these two types of connections was loaded statically, with a slow increase in force until failure. The paper presents results of the experimental testing. Three specimens were made and tested for each type of the connection. Experimental results were subsequently compared with numerical models. The achieved results were also compared with the assumption according to the currently valid standard. The results indicate that a connection using fully threaded screws provides a better load-carrying capacity.

Continuous shear connectors in a shape of dowels are one of the newer shapes of composite steel-concrete bridges. In this article results of push-out tests of such a dowel with geometry designed at Faculty of Civil Engineering, Technical University of Kosice are presented and compared to the previous research.

This paper presents results from an extensive study on laminated timber beams manufactured without adhesives or metal fasteners. The use of such elements enables the implementation of the 4R principles in construction (Reduce, Reuse, Recycle, Repair). Prior to the testing of beam elements, tests were conducted on embedment strength of wooden dowels in comparison with conventional steel ones. The specimens varied in dowel diameter and in the angle of applied load relative to the grain direction. In addition to mechanically inserted dowels, an innovative dowel-welding method was examined. Welding enhances the bonding between lamellas, thereby improving overall mechanical performance. Further investigations involved beams with lamellas joined by dowels of different diameters, spacing, orientation, and installation methods. Experimental results were compared with analytical models for composite beams. The study showed that, except through the entire height of the beam section, it is possible to use dowels that connect only two lamellas, which is important for production. Dowels placed at 45° in relation to the lamella fibers showed approximately 20% greater capacity. It is also important to mention that study shows how welded dowels are only useful when they have larger diameters because then they achieve a significant level of cohesion.

In this study, the aim was to optimize the cross-sectional geometry of auxetic dowels for furniture joints. For this purpose, two different sizes of auxetic dowels were chosen, one for frame- and the other for panel-type furniture joints for designing the cross-sectional geometry. Auxetic patterns that are created on the cross-sectional area cause deficiency of the materials, and this phenomenon decreases the modulus of elasticity (MOE) and increases the member stress. Accordingly, maximum MOE values and minimum Poisson’s ratio levels were determined for the optimum strength-auxetic behavior relation by means of a Monte Carlo method. Furthermore, Poisson’s ratio of the optimized dowel’s cross-section was confirmed with experimental tests, numerical analyses and analytical calculations. As a result, Poisson’s ratio values were obtained as negative values and confirmed, which means the dowels designed in this study had auxetic behavior. In conclusion, it could be said that studies should be conducted on the performance of auxetic dowels in both frame and panel furniture joints.

Aggregate interlocking and dowel bar systems are the two primary mechanisms in a jointed plain concrete pavement for transferring the wheel loads from the loaded slab to the adjacent unloaded slab, avoiding critical stresses and excessive deformations across the joint. Aggregate interlocking is suitable for small joint openings, while the dowel bar provides effective load transmission for both smaller and wider joint openings. In this study, a three-dimensional finite element model was developed to investigate the structural performance of dowelled jointed plain concrete pavements. The developed model was compared with an analytical solution, i.e., Westergaard’s method. The current study investigated the effectiveness of the dowel bars in jointed plain concrete pavements considering the modulus of elasticity and the thickness of the base layer, as well as dowel bar diameter and length. Furthermore, the load transfer efficiency (LTE) of a rounded dowel bar was compared with that of plate dowel bars (i.e., rectangular and diamond-shaped dowel bars) of a similar cross-sectional area and length. This study showed that the LTE was enhanced by 4% when the base layer’s modulus of elasticity increased from 450 MPa to 6000 MPa, while the increase in stress was 23%. A 1.2% improvement in the LTE and a 2.1% reduction in flexural stress were observed as the base layer’s thickness increased from 100 to 250 mm. Moreover, increasing the dowel bar’s diameter from 20 mm to 38 mm enhanced the LTE by 4.3% and 3.8% for base layer moduli of 450 MPa and 4000 MPa, respectively. The corresponding rise in stresses was 10% and 5%. The diamond-shaped dowel bar of a 50 × 32 mm size showed a 0.48% increase in the LTE, while sizes of 100 × 16 mm and 200 × 8 mm reduced the stress 6.7% and 23.1%, respectively, compared to that in the rounded dowel bar. With rectangular dowel bars, a 4% rise in the stress was noted compared to that with the rounded dowel bar. Increasing the length of the diamond-shaped dowel bar slightly improved the LTE but had no impact on the stress in the concrete slab. The findings from this study can help highway engineers improve pavements’ durability, make cost-effective decisions, contribute to resource savings in large-scale concrete pavement projects, and enhance the overall quality of infrastructure.

This study aims to evaluate the structural behaviour of dowel laminated timber (DLT) made of fast-growing pine and eucalyptus lamellae and different dowel diameters. Shear tests on dowelled connections and four-point bending tests on structural size panels were performed, and the slip modulus and bending properties, respectively, were obtained. The bending stiffness and strength of pine panels fastened with guatambú (5.05 and 20.05 kN/mm2) or eucalyptus dowels (5.29 and 17.13 kN/mm2), suggesting that dowel species had no influence on the panel’s bending properties. The analysis of the bending stiffness and strength of eucalyptus panels fastened with 18 mm (11.04 and 44.29 kN/mm2) or with 15 mm dowel diameter (11.06 and 51.50 kN/mm2) indicated that dowel diameter had no substantial influence on the bending properties. Furthermore, the stiffness values of the panels were similar to those of their constitutive individual lamellas, which, in turn, did not comply with the structural requirements of the Uruguayan Standard. Additional analytical results of the effective stiffness using the slip modulus were close to those found in the experimental bending tests. The results from this study are useful in understanding the mechanical behaviour of DLT panels and provide the basis for the improvement of Uruguayan mass timber products.

This article projects the systematic approach for reducing the rejection during manufacturing of non-threaded fasteners i.e., Dowel Pin by Basic Quality tools. It includes the systematic study of the manufacturing process of non-threaded fastener and its inspection at different stages of manufacturing. The analysis of Dowel Pin’s manufacturing process has been taken place at industry A and modification in the process, drawing and work holding device of the Machine Tool have been done. After implementation of the modifications in the manufacturing process, the desired results have been achieved. The improvement has been visualized in the results.

The shear capacity was evaluated for specimens connected by beech dowels and composite dowels. The bearing capacities were calculated by the shear capacity formulas of metal dowel connectors in the GB 50005 (2017), NDS (2018), and EN 1995-1-1 (2014) standards. The results showed that, except for the specimen connected by one composite dowel calculated by the GB 50005 standard (2017), the remaining calculation differences were larger. Based on the failure mode, the force analysis of the beech dowels and the composite dowels was carried out. A calculation formula for the shear bearing capacity of the beech dowels and the composite dowels was proposed. The calculated results were in strong agreement with the test results, and the margins of difference were less than 10%. Furthermore, the formulas for two and four connectors were investigated. When the number of effective connectors was calculated by the GB 50005 standard (2017), the differences between the test values and the calculated values were less than 9.36%.

Tests were carried out to develop and manufacture various types of auxetic dowels using 3D printing technology. These dowels were then used to connect L-type corner joint specimens for case furniture, and their strength and stiffness were analyzed through experimental, theoretical, and numerical means. In the scope of the study, eight different types of auxetic dowels including two inclusion types, two inclusion sizes, and two dowel hole diameters, as well as a reference non-auxetic dowel, were designed. Accordingly, a total of 180 specimens that included 10 replications for each group were tested; 90 were tested under tension and the remaining 90 were tested under compression. The results demonstrated that the assembly force required for the corner joints connected with auxetic dowels was significantly lower compared to non-auxetic dowels. Furthermore, the numerical and theoretical analyses yielded similar outcomes in this study. Both analyses revealed that the dowels used to connect the corner joints experienced substantial stresses during mounting and bending, ultimately leading to their failure. Upon concluding the test results, it was observed that the corner joints connected with dowels featuring rectangular inclusions exhibited superior performance when compared to those with triangular inclusions. In light of these findings, it can be concluded that further enhancements are necessary for auxetic dowels with rectangular inclusions before they can be utilized as alternative fasteners for traditional dowels.

Herein, a beech wood dowel reinforced with a self-tapping screw (composite dowel in brief) is proposed. Composite dowels were welded into the predrilled holes by high speed rotation. Force-displacement curves were obtained using a single-shear and dual connection. A double-peaked pattern was found in the bearing process, indicating that the wooden dowel and the self-tapping screw had a synergistic bearing effect in the bearing process. Regarding the failure mode, the self-tapping screw and the wooden dowel were bent, whilst the default wooden dowel fractured. Further, the numerical simulation was carried out using the finite element analysis software ABAQUS, and the result differed from the test value by only 4.30%, showing a high prediction accuracy. The study of the bearing capacity of the composite dowels provides a theoretical basis for the practical application of wooden dowels reinforced by self-tapping screws.