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Shear strength of a reinforced concrete (RC) member should be larger than its flexural strength, in order to prevent the shear failure, which is sudden and brittle. The reliability of a RC beam against the shear failure is closely related to the reliability of the equation determining its shear strength. In this study, the reliabilities of shear strength equations of RC beams were investigated by constructing the performance function between prediction equations and experimental results using a second-moment approach. It is assumed that the random variables are statistically independent, and the correlation effects are not taken into account. It is observed from the reliability rankings that the equation of EN 1992:2004 yields the lowest failure probability while the equation of Zsutty is the highest failure probability. [ABSTRACT FROM AUTHOR]

Metal additive manufacturing technologies, such as electron beam powder bed fusion (PBF-EB), rely on layer heating to overcome the so-called "smoke" phenomenon. When scaled up for industrial manufacturing, PBF-EB becomes less productive due to the lengthy preheating process. Currently, only the electron beam (EB) is used for preheating in PBF-EB, resulting in increased manufacturing times, energy consumption, and in some cases limiting the applicability of the technology. In this study, a new preheating approach is suggested that incorporates a near-infrared radiation (NIR) emitter inside an PBF-EB system. The NIR unit eliminates the need for EB heating, reducing build time and powder charging. Successful builds using 316 L and Ti6Al4V precursor powders validate the feasibility of the proposed approach. The produced samples exhibit similar properties to those obtained by the standard PBF-EB process. The introduction of NIR technology also reduced build cost and increased the service intervals of the electron gun. [ABSTRACT FROM AUTHOR]

Results of computational experiments on studying multiphase flow and interphase interaction in the volume of an industrial 50-ton tundish of a continuous caster, including when blowing with argon through bottom blowing blocks, are presented. A mathematical model has been developed that makes it possible to predict the dynamics of melt mixing at a given casting speed. The pattern of influence of the layout of the ladle's working space on the area of "stagnant zones" in the ladle volume has been found. [ABSTRACT FROM AUTHOR]

Motivation: The analysis of vibrations of an elastic beam is one of the persistently challenging problems in engineering and mathematics. The differential equation of vibrations of a beam under large deformation, or the typical vibrations of an elastica, is hard to approximate and solve with the formulation in Cartesian coordinates. Objective: The higher-order nonlinear vibrations and couplings of modes of beams are analyzed with a novel method for a better understanding of dynamic properties. Method: The extended Galerkin method is used to obtain the first- to third-order nonlinear vibration frequencies and mode shapes of a cantilever beam with the exact equation of a beam with larger deflection, and the differential equation is transformed to a nonlinear algebraic equation for an improved analysis and solutions with the aid of linear mode shape functions. Results: From a cantilever beam in nonlinear vibrations, the numerical solutions of frequencies and mode shapes show that the approximate solutions are accurate in comparison to the exact solutions for small amplitudes with other methods. Conclusions: The effectiveness of the extended Galerkin method in solving nonlinear vibration equations is further demonstrated with a novel procedure and known results. [ABSTRACT FROM AUTHOR]

Simulation of a 3-point bending of a square beam located on supports by an edge but not on a flat side is carried out. The calculation is based on the fundamental relationship between the specific fracture energy G and the change in the sample compliance during crack propagation. In the ANSYS system, the dependence of the compliance on the crack length was obtained using the ORIGIN program. The derivative of this function along the crack length determines the change in the sample compliance. A universal equation for determining G in a wide range of geometric dimensions is obtained. [ABSTRACT FROM AUTHOR]

With the development of recycled aggregate concrete (RAC), the recovery rate of construction waste is improved, and the pollution problem is alleviated. In particular, RAC beams strengthened with prestressed carbon fiber reinforced plastics (CFRP) can exhibit improved mechanical properties, expanding RAC application. Four groups of reinforced RAC beam specimens contained 0%, 40%, 70%, and 100% recycled coarse aggregate, respectively. Each group of beams was first pre-cracked and then strengthened by prestressed CFRP with one layer and two layers respectively. Finally, the bearing capacity tests were performed for these beams. The test results show that as the recycled coarse aggregate content increases, the cracking moment and ultimate load capacity of the beam decrease, while its crack width increases. As the CFRP layer increases, the deformation and crack width of the beam decreases, while the number of cracks increases. The prestressed CFRP also exhibited tensile and peeling failure. A beam deflection calculation model was established by introducing a coefficient k representing the interaction between recycled aggregate and CFRP. The influence coefficient of concrete elongation on the crack width and average crack spacing of the beam was modified, and the crack width analysis model of the beam was established. The calculated results are in good agreement with the experimental observations. It can provide reference for the application and design of recycled concrete beams strengthened with prestressed CFRP. [ABSTRACT FROM AUTHOR]

Introduction: Breast cancer has been a leading malignancy in women across the globe. In breast conserving treatment, radiation therapy plays an important role. This is clinically approved that breast conserving surgery followed by adjuvant radiation therapy produces as the same survival rate as radical breast RT. The aim of this study was to find out suitable number of IMRT fields to treat left-sided breast cancer and analyze the effects of increasing the number of fields in IMRT plans. Material and Methods:We selected 105 patients retrospectively for this study diagnosed with left-sided breast cancer of age ranging from 33 to 74 years. There were 52 cases of chest wall (CW) irradiation including SCF, 20 cases of BCS and 33 cases were of CW including supra-clavicular fossa (SCF) and internal mammary lymph nodes (IMLN). Results:Our main objective was to analyze dose-distribution of left lung. Monitor Units (MUs) were also recorded and found almost same in these three modalities ranging from 1200 to 2000. The mean value of V20Gy(cc) in 11-bIMRT technique was found less by 8-17cc as compared to 7-and 9-bIMRT technique. It was observed that 11-bIMRT technique yielded slightly better outcomes in terms of V20Gy(cc). Conclusion: The technique 7-bIMRT gives slightly better result in controlling low-dose volume of underlying lung and heart. As the number of IMRT beams increases, it translates into better outcomes in terms of reducing high-dose volume as well as mean-dose of left lung. So, it is prudent to use 'N' number of IMRT fields such as 7= N =11 in left breast RT. [ABSTRACT FROM AUTHOR]

This article proposes the use of Jacobi polynomials as shape functions for the free vibration analysis of beam, plate, and shell structures. Jacobi polynomials, indicated as P p (γ , θ) , belong to the family of classical orthogonal polynomials, and depend on two scalar parameters γ and θ, with p being the polynomial order. The Jacobi-like shape functions are built in the context of the Carrera unified formulation, which permits the expression of displacement kinematics in a hierarchical form. In this manner, it is possible to adopt several classical to complex higher-order theories with ease. Particular attention is focused on the attenuation and the correction of the shear locking. The results have been compared with analytical results from the literature. For the plate benchmark, analytical results are introduced as the reference results in this article for the first time using the closed form of CUF. Beams, plates, and shells with different thicknesses have been considered. It is demonstrated that the parameters γ and θ are not influential for the calculations. [ABSTRACT FROM AUTHOR]

The study analyzed the influence of periodic and aperiodic stiffness distribution for the four-element Bernoulli-Euler beam on the first two eigenfrequencies and the dynamic stability of the system. The influence of increasing the ratio of cross-sections of the analyzed elements was also analyzed. Significant differences were found in eigenfrequencies and dynamic stability. Using the variational Hamilton principle, the equation of motion was derived, on the basis of which the values of the eigenfrequencies were determined, and the transformation into the form of the Mathieu equation made it possible to determine the dynamic stability for the analyzed structures. [ABSTRACT FROM AUTHOR]

The microhistological technique is the most popular methodology used to determine the wild and domestic ungulates diet; its success depends on the development of a reliable reference catalog. Objective: To describe and analyze the epidermal structures of the plants available for wild and domestic ungulates in Sonora, Mexico, using the microhistological technique. Methodology: A comprehensive collection of the plants available for wild and domestic ungulates was carried out at UMA Rancho Noche Buena, in order to subsequently identify their genus and species. Plant structures were analyzed with the modified microhistological technique, scraping the beam and underside cuticle of leaf plants. In addition, at least one photograph was taken to characterize them. Results and Discussion: The epidermal structures of 95.95% of the analyzed plants were observed with the microhistological technique and its modification. The distinctive structures of 74 plant species were identified, in order to describe the main characteristics of each species. A catalog of microhistological references was developed from the data collected; it included information about the morphology and arrangement of structures such as: epidermal cells, stomata and trichrome. A difference was found between the beam and underside of the leaves in 23% of the species. Conclusion: A reliable microhistological reference catalog should consider possible differences between the beam and underside of the leaves of plants. [ABSTRACT FROM AUTHOR]

Failure in beams reinforced with a small amount of transverse reinforcement is brittle due to reinforcement rupture after critical shear cracking occurs. To eliminate this problem, standards recommend formulas to calculate the minimum amount of transverse reinforcement in reinforced concrete structures. Reinforcement can resist loads after the first crack's appearance, preventing beam rupture from being brittle but making it somewhat ductile. This paper presents a theoretical experimental analysis to determine the minimum transverse reinforcement ratio in beams of high-strength ordinary portland cement concrete (BHSOPCC), low-strength ordinary portland cement concrete (BLSOPCC), and low-strength geopolymeric concrete (BLSGC). The beam dimensions were 150 x 450 x 4500 mm. They were subjected to a four-point bending test to assess shear failure. The transverse reinforcement ρsw,minfyk ranged from 0 to 1.16 MPa, in the ranges provided by ACI 318-19, AASHTO LRFD, fib Model Code, and ABNT NBR 6118:2014. This paper investigates the minimum shear reinforcement ratio for various types of concretes with different strengths and attempts to reevaluate the associated standards that have already been established. The parameter τwy*/τwcr proposed in this paper to define whether or not a beam has minimum transverse reinforcement is more appropriate. [ABSTRACT FROM AUTHOR]

The aim of the research was to examine the initial grades of gymnasts who participated in the finals in the balance beam discipline at the World Cup in Doha. The hypothesis of this research should show that the initial grade has a large share in the success when performing the composition on the beam. The sample of participants consists of eight gymnasts who qualified for the final in the beam discipline at the FIG World Cup Series competition - Doha (Qatar) in 2022. These gymnasts come from six national federations, which are shown with their starting grades, errors in performance, final grades and placement. In this case study, the research shows that the performance of gymnasts at the top level is very safe, because the finalists on beam did not make major mistakes, they fulfilled all specific requirements and some achieved bonus elements. [ABSTRACT FROM AUTHOR]

Over the years, deep reinforcement learning (DRL) has shown great potential in mapless autonomous robot navigation and path planning. These DRL methods rely on robots equipped with different light detection and range (LiDAR) sensors with a wide field of view (FOV) configuration to perceive their environment. These types of LiDAR sensors are expensive and are not suitable for small-scale applications. In this paper, we address the performance effect of the LiDAR sensor configuration in DRL models. Our focus is on avoiding static obstacles ahead. We propose a novel approach that determines an initial FOV by calculating an angle of view using the sensor's width and the minimum safe distance required between the robot and the obstacle. The beams returned within the FOV, the robot's velocities, the robot's orientation to the goal point, and the distance to the goal point are used as the input state to generate new velocity values as the output action of the DRL. The cost function of collision avoidance and path planning is defined as the reward of the DRL model. To verify the performance of the proposed method, we adjusted the proposed FOV by ±10° giving a narrower and wider FOV. These new FOVs are trained to obtain collision avoidance and path planning DRL models to validate the proposed method. Our experimental setup shows that the LiDAR configuration with the computed angle of view as its FOV performs best with a success rate of 98% and a lower time complexity of 0.25 m/s. Additionally, using a Husky Robot, we demonstrate the model's good performance and applicability in the real world. [ABSTRACT FROM AUTHOR]

The combination of carmustine, etoposide, cytarabine, and melphalan (BEAM) followed by autologous stem cell transplantation (ASCT) is a commonly used intensification regimen for patients with Hodgkin lymphoma. As etoposide and cytarabine dosing are not defined, we conducted a retrospective, multicenter study, to compare efficacy and toxicity in 130 patients with Hodgkin lymphoma receiving etoposide and cytarabine at either 200 mg/m2/d (n = 50), 400 mg/m2/d (n = 35), or etoposide 200 mg/m2/d and cytarabine 400 mg/m2/d (n = 45). Progression-free survival and overall survival were not associated with the intensity of conditioning. Increased conditioning intensity was associated with longer duration of thrombocytopenia, a higher number of transfused RBC and platelet units and a higher frequency of mucositis, but serious adverse events or infectious complications were not increased. The intensity of BEAM regimen was not associated with survival but with the rate of cytopenia and mucositis advocating for the use of lower dosing in frail patients. [ABSTRACT FROM AUTHOR]

Free electron lasers (FELs) are becoming more and more popular as sources of radiation for research purposes in many fields of science. They are frequently employed in second harmonic generation (SHG) studies. SHG is an important effect of nonlinear responses of matter to irradiation. It should be separated from the second harmonic of the radiation source, FELs, for correct analysis of the response. Using an analytical model for harmonic powers evolution in a single-pass FEL, we demonstrate the dependence of FEL harmonics on the key parameters of beams and undulators and show that it is possible to reduce the second FEL harmonic content if the energy spread of an electron beam is increased. For LEUTL FEL radiation in the visible range, we analytically demonstrate a reduction in the second harmonic power by an order of magnitude if electron energy spread is increased twice, which still allows efficient bunching at the fundamental wavelength. The method is valid regardless of the photon energy and, therefore, the absorption edge of the target material, and as such, it is valid also in the X-ray band. [ABSTRACT FROM AUTHOR]

The UHPC flexural database: Validation of a design approach for bending with or without axial force In the present paper, test data of 228 ultra‐high performance concrete (UHPC) beams are consolidated in a database. Different shapes of cross‐section and reinforcement configurations are considered, including prestressing, exclusively fibre‐reinforced and exclusively bar reinforced members. The evaluation of the literature shows that in many cases important material parameters are inadequately documented. In addition, the use of different, often non‐standardised methods of material characterisation makes it difficult to compare the individual studies. Therefore, all data are first carefully checked, standardised, and partially complemented. Subsequently, the data sets of the database are used to validate an approach for the flexural design of beams with mixed reinforcement. This approach was developed with the participation of the authors and is presented here for the application to cross‐sections with complex geometry. When being evaluated with the mean values of the material parameters, the model fits well for both the universe of the tests and individual model parameters. An acceptable level of safety is obtained by limiting the characteristic value of the post‐cracking tensile strength to 0.6 times the mean value. The 5%‐quantile of the ratio between experimental and calculated moment resistance Mexp / Mcal is then Q0.05 = 0.97 for the universe of the 228 data sets. [ABSTRACT FROM AUTHOR]

This numerical and statistical study deals with the evaluate the effects of forces and material types on safety factor and equivalent alternating stress of beams made of metal materials. Numerical calculations were performed by using ANSYS Workbench software. Design of analyzes based on different determining factors was determined utilizing Taguchi L9 orthogonal array design consisting of two determining factors consisting of three levels. The first and second determining factors were chosen as applied force and material type, respectively. In the finite element modeling, beams with clamped-free boundary conditions were considered. Determination of optimal levels of all factors was found using signal-to-noise ratio analysis. The contribution rate and significance level of all determining factors on the safety factor and equivalent alternating stress were calculated utilizing analysis of variance. According to the results calculated from this study, the optimum results for safety factor and equivalent alternating stress of beams were obtained by using the first levels of all determining factors. While the increase in the applied force values causes a decrease in the safety factor, it leads to an increase in the equivalent alternating stress. [ABSTRACT FROM AUTHOR]

The new American Concrete Institute (ACI) design code for glass fiber–reinforced polymer (GFRP)–reinforced concrete (RC) members specifies a single value of 1.20 for the bond-dependent coefficient (kb) of all types of GFRP bars. This value was chosen based on test data from this project, as well as a compilation of data available in the literature. This paper reports on an experimental study that assessed the kb for the new generation of GFRP bars from five different manufacturers with different surface types: deformed/ribbed, helically deformed, helically grooved, double-helical wrap/sand-coated, and sand-coated. Two bar sizes (No. 5 and No. 8)—with 15.9 and 25.4 mm nominal diameters representing the typical range of GFRP-reinforcing bars used in practice as longitudinal reinforcement in concrete members subjected to bending—were selected from each of the manufacturers. Five RC beam replicates were used to increase experimental accuracy. Therefore, a total of 60 beams, including 50 beams reinforced with GFRP bars and 10 control beams reinforced with conventional steel bars for comparison purposes, were constructed and tested to failure according to a predetermined test method. Based on the analysis, the study confirms using the bond-dependent coefficient value of 1.20 as adopted in the new ACI design code for GFRP–RC members. This value is recommended for GFRP bars complying with (or exceeding) the material specification listed in the ASTM International standard specification for solid round GFRP bars for concrete reinforcement. [ABSTRACT FROM AUTHOR]

The flexural behavior of corroded reinforced concrete (RC) beams strengthened with textile reinforced concrete (TRC) was analyzed and discussed in this work. Thirteen beams, including one reference beam, three corrosion-only beams, and nine TRC-strengthened corroded beams, were tested under four-point bending. The failure modes, cracks, bearing capacity, load–displacement curves and ductility of the tested beams were analyzed. The results showed that the TRC played a role in increasing the number of cracks and decreasing the width of the cracks in the corroded RC beams. In terms of improving the bearing capacity, TRC can improve the bearing capacity of corroded beams even more than the reference beams, and the strengthening after removing the concrete cover of corroded RC beams is better than direct strengthening. The corroded beams after TRC strengthening exhibited improved ductility. The energy absorption index of the TRC-strengthened corroded RC beams increased with the increase in the number of textile layers. [ABSTRACT FROM AUTHOR]

In this paper, a new approach is developed to numerically evaluate the structural performance of deteriorated prestressed concrete beams using the finite element analysis application RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology). A prestressing steel element was modified to represent the interaction between deteriorated concrete and prestressing steel. Considering the corrosion effects—as shown by the reduction of the prestressing steel section and loss of bond—a nonlinear material model was proposed for deteriorated prestressed concrete behavior. The modified damage index is intended to provide a numerical method for quantifying the structural performance of deteriorated prestressed concrete beams. The analytical procedure developed for the performance evaluation of deteriorated beams was validated by comparison with the credible test results, thereby enabling a more reliable and rational prestressed concrete beams design process. [ABSTRACT FROM AUTHOR]

Abstract The effect of the semi-rigid connection between beams and columns on the global behavior of reinforced concrete (RC) structures was investigated. The relative rotations in the nodes of the spatial frames were determined using the analytical approach proposed by Alva and El Debs. The rotational restraint factor ( α r) was defined and applied in each node of the spatial frames. RC spatial frames with total heights of 21, 42, and 63 m were considered. It was found that the semi-rigid connection increases the lateral displacements, the 2nd order effects, and the γ z values. The lower the stiffness of the nodes, the lower the influence of α r on the global results. The total fixed beam-column connections can lead to an unrealistic behavior of the spatial frame and thus to global results.

IntroductionCarmustine (BCNU), etoposide, cytarabine, and melphalan (BEAM) are a widely used high-dose chemotherapy regimen for autologous stem cell transplantation transplant (ASCT) in lymphoid malignancies. During BCNU shortages, some centers switched to fotemustine-substituted BEAM (FEAM). Neutropenic enterocolitis (NEC) is a life-threatening complication occurring after intestinal mucosa damage related to intensive chemotherapy. NEC mortality may be up to 30%–50%. In our study, we compared NEC incidence, symptoms, mortality, and transplant outcome in terms of overall survival (OS) and progression-free survival (PFS) in the BEAM vs. FEAM groups. Furthermore, we compared the cost of hospitalization of patients who did vs. patients who did not experience a NEC episode (NECe).MethodsA total of 191 patients were enrolled in this study (N = 129 and N = 62 were conditioned with BEAM and FEAM, respectively). All patients received bed-side high-resolution ultrasound (US) for NEC diagnosis.Results and discussionNEC incidence and NEC-related mortality were similar in the BEAM and FEAM groups (31% and 40.3%, p = 0.653, and 5% and 8%, p = 0.627, respectively). At a median follow-up of 116 months, no difference was noted between BEAM vs. FEAM groups in terms of OS and PFS (p = 0.181 and p = 0.978, respectively). BEAM appeared equivalent to FEAM in terms of NEC incidence and efficacy. The high incidence of NEC and the low mortality is related to a timely US diagnosis and prompt treatment. US knowledge in NEC diagnosis allows to have comparable days of hospitalization of patients NECpos vs. patients NECneg. The cost analysis of NECpos vs. NECneg has been also performed.

This paper surveys the existing landscape of standards relevant to heliostats, identifies their gaps, and proposes a path forward to a comprehensive set of heliostat guidelines, technical specifications, and standards under the framework of International Electrotechnical Commission (IEC) TC 117. Gaps in existing guidelines and standards are surveyed using a three-tiered taxonomy: component-level, heliostat-level, and field-level. At each level, the gap analysis is followed by a proposal for a coordinated path forward on the development of standards. At the component level, advances in the understanding of wind loading should inform a technical specification for drives and structures. Reflectors require consolidation of measurement guidelines into existing standards documents. Communications & controls require technical standards to inform their selection and secure implementation. At the heliostat level, IEC 62817 (solar trackers) adequately characterizes drive systems, structures, and electronics, but requires adaptation to heliostats’ use patterns, operating modes, and expected life cycles. IEC 62817 does not address heliostat beam quality and pointing accuracy, but the process for determining both is elaborated in the SolarPACES Guideline for Heliostat Performance Testing. This SolarPACES document requires two main modifications: adaptation to IEC language and inclusion of testing after heliostats which have undergone accelerated weathering and mechanical cycling (to understand performance degradation). At the field level, IEC 62862-4-2 addresses the function and control of heliostat fields but does not cover the statistically rigorous testing of heliostat groups, or field performance factors like security and soiling. The addition of documents under IEC-62862-4 is proposed to address this gap.

The main objective of this study is to define the Green functions for four-point boundary value problems. It is a further aim to clarify what properties the Green functions have and to present a method for calculating the elements of these Green functions. The examples are related to two heterogeneous beams with four supports: the (first) [second] beam is (fixed)[pinned] at the endpoints while the intermediate supports are two rollers. Determination of the eigenfrequencies leads to four-point eigenvalue problems associated with homogeneous boundary conditions. Utilizing the Green functions that belong to these eigenvalue problems we can transform those into eigenvalue problems governed by homogeneous Fredholm integral equations. Then a numerical solution is computed by reducing the homogeneous Fredholm integral equations into algebraic eigenvalue problems.

The primary goal of the static analysis for the vehicle axle suspension systems consists in finding the equilibrium position of the mechanism in relation to the car body (which is considered the fixed reference part), under the action of the contact forces on wheels resulting from the overall dynamic balance of the vehicle. In the equilibrium position of the suspension, the reaction forces in the elastic elements of the suspension are to be determined, these being necessary in order to properly sizing these elements. In the present work, the previously stated problem is addressed by using an analytical method (and the corresponding computing program) that was detailed in an earlier work by the author. The study in this paper is focused on determining the reaction forces from the elastic elements of one of the most used types of axle suspension system, namely the one with a five-bar guidance mechanism.

The main problems of research are: the impact of social environment on human behaviour has contributed to the debate against the management view of universal applicability, and also there are multiple challenges for the African indigenous management theories development. The research aims to have an indigenous management philosophy of the Hediya people in Ethiopia in their mud-hut construction. The study is carried out using the metaphoric method of the qualitative research approach. The researcher collected metaphoric data from the Hediy-nefra of Lemo community where researcher was born, and through his observation while living in his lifetime. The findings include the strongest essence of team work, strategic recruitment and selections, motivating of employees through financial and non-financial factors such as team environment and work design. Particularly, the finding includes: continuing of employees’ benefit for the ex-employees is important not only for them but also for the organisation on the future; employees are enforced to give focus on the work quality not to have current work related benefits but also it is a means of getting employment and finance in the future. In the management idea of Hediya peoples’ indigenous hut building system, the relationship of an organisation with competitors was being practiced positively and helping each other, so that it needs to be enforced. Besides, the good quality of current work will attract a lot of employers other than current workers/organisation with referent of previous hut construction quality. The hut construction concept of Ethiopians’ management practices should be verified.

General solution of the time-dependent strain energy release rate for delamination cracks in multilayered functionally graded load-bearing beam structures which exhibit non-linear creep is derived. The material is functionally graded along the length of layers. The Ramberg-Osgood stress-strain relation is used by assuming that the material in each layer behaves differently in tension and compression. The second term in the Ramberg-Osgood relation includes time dependence to treat the non-linear creep. The solution derived holds for multilayered functionally graded beams with arbitrary number of layers which have different width and material properties. The solution is applied for a delamination in a multilayered beam with a built-in end. An analysis is performed also by considering the balance of the energy in the multilayered beam configuration for the sake of verification. The effect of time is also studied. It is found that the strain energy release rate grows with the time. The results obtained here are useful for understanding the time-dependent delamination in multilayered functionally graded structural components subjected to non-linear creep.

The United Nations Sustainable Development Goals (UN SDGs) ensure future human well-being. However, they face challenges due to the pressing need to reduce carbon emissions, with nearly 40% originating from the construction sector. With the current global environmental and energy crisis, there is a pressing need to address building carbon emissions and prioritise investments in passive strategies for improving indoor thermal comfort. Exploring fast-growing bio-based materials like bamboo, straw, hemp, and flax directly addresses these concerns, fostering environmental sustainability. Material selection in construction is crucial for advancing the SDGs, for example, promoting sustainable cities and communities (SDG11) and responsible consumption and production (SDG12). This paper proposes a comparative analysis of conventional and bio-based construction materials, focusing on their production stages through life cycle analysis. Tools such as Building Emissions Accounting for Materials (BEAM) and the Methodology for Relative Assessment of Sustainability (MARS) enable a detailed comparison. The results highlight the benefits of bio-based materials in storing carbon more rapidly and their lower environmental impact compared to conventional alternatives. Moreover, bio-based materials contribute to indoor moisture regulation and a healthier indoor environment, underscoring their potential to accelerate progress towards the UN SDGs through informed material choices in design practices.

Objective. The aim of the study is to study the operation of multi-span beams with point masses under the simultaneous action of vector kinematic and force loads. Taking into account the influence of elastic-damping supports.Method. The study is based on the solution of the boundary value problem and modeling.Result. Free transverse vibrations of multi–span beams of constant cross-section (within each j-th span Aj, and Gj) are investigated taking into account elastic-damping discrete supports. Free and forced harmonic vibrations of the beam from vector kinematic and force perturbations are considered. Examples of solutions for various conditions of fixing a three-span beam at different point masses are given.Conclusion. The author’s development can be adapted to the fluctuations of the continuo-discrete rods. This algorithm allows you to determine the natural frequencies and forms of free oscillations. It is also possible to calculate multi-span rods for the simultaneous action of vector kinematic and dynamic loads.

We consider the boundary value problem of finite beam deflection on elastic foundation with two point boundary conditions of the form $ u^{(p)}(-l) = u^{(q)}(-l) = u^{(r)}(l) = u^{(s)}(l) = 0 $, $ p < q $, $ r < s $, which we call elementary. We explicitly compute the fundamental boundary matrices corresponding to 7 special elementary boundary conditions called the dwarfs, and show that the fundamental boundary matrices for the whole 36 elementary boundary conditions can be derived from those for the seven dwarfs.