Continuous Loading Research Articles

Experimental Investigation of Cumulative Damage and Self-Healing Properties of Smart Cementitious Composite under Continuous Compression Load.

This study investigated the effect of sustained loading on the cumulative damage of a newly developed smart cement-based self-healing composite material (SMA-ECC). SMA-ECC is composed of engineered cementitious composite (ECC) and shape memory alloy (SMA) fibers. A uniaxial compressive test with five predefined loading levels (0%, 30%, 40%, 50%, and 60% of compressive strength) was conducted on SMA-ECC hollow-cylindrical specimens and ECC control hollow-cylindrical specimens. The cumulative damage was mainly determined by changes in the total water absorption of different groups of specimens during three different periods (not loaded, at a predefined loading level, and after unloading). A normalized water content index was proposed to couple the effects of self-healing, sustained loading, and cumulative damage. The test results indicate that the cumulative water absorption of SMA-ECC was 35% lower than that of ECC, which may indicate less irreparable damage. In addition, the self-healing ability of SMA-ECC specimens under different compression load levels was evaluated through normalized water content analysis. SMA-ECC exhibited a 100% repair rate at load levels of 30% and 40%. At a higher load level of 60%, the repair rate of SMA-ECC was 76%. These results collectively emphasize the significant impermeability and self-healing performance of SMA-ECC after unloading.

Influence of Crystal Structure on the Set of Physicomechanical Characteristics of Composite Materials Based on Ultra-High Molecular Weight Polyethylene

Composite fibers containing boron(III) have been obtained based on solid solutions of cellulose in N-methylmorpholine-N-oxide and orthoboric acid with their subsequent transformation into a viscous-flow state. The rheological behavior of cellulose solutions with different content of orthoboric acid and water studied under conditions of continuous and dynamic shear loading has confirmed the intermolecular interaction between the components. It has been shown that the mechanical characteristics of the composite fibers obtained from a 16% solution in N-methylmorpholine-N-oxide are comparable to these for hydrated cellulose fibers. The process of transformation of the composite fibers of various compositions into carbon fiber has been investigated by means of thermogravimetric analysis and differential scanning calorimetry. Chemical, structural and morphological properties of composite hydrated cellulose fibers and carbon fibers obtained from them have been studied using FTIR-spectroscopy, X-ray diffraction, and scanning electron microscopy. The influence of boron(III) compounds on the carbonization process and the formation of graphite-like structures in carbon fiber has been investigated by Raman-spectroscopy.

Boron(III)-Containing Composite Hydrated Cellulose Fibers As Precursors of Carbon Materials

Composite fibers containing boron(III) have been obtained based on solid solutions of cellulose in N-methylmorpholine-N-oxide and orthoboric acid with their subsequent transformation into a viscous-flow state. The rheological behavior of cellulose solutions with different content of orthoboric acid and water studied under conditions of continuous and dynamic shear loading has confirmed the intermolecular interaction between the components. It has been shown that the mechanical characteristics of the composite fibers obtained from a 16% solution in N-methylmorpholine-N-oxide are comparable to these for hydrated cellulose fibers. The process of transformation of the composite fibers of various compositions into carbon fiber has been investigated by means of thermogravimetric analysis and differential scanning calorimetry. Chemical, structural and morphological properties of composite hydrated cellulose fibers and carbon fibers obtained from them have been studied using FTIR-spectroscopy, X-ray diffraction, and scanning electron microscopy. The influence of boron(III) compounds on the carbonization process and the formation of graphite-like structures in carbon fiber has been investigated by Raman-spectroscopy.

The damage mechanism of tension-tension fatigue interaction with creep damage of the compacted graphite cast iron alloy at high temperatures

The tension-tension fatigue test of the compacted graphite cast iron (CGI) alloy was carried out by RDL100 universal testing at 500 °C and 550 °C, respectively. A tension-tension trapezoidal load is applied to the CGI specimen. Because of the time-dependent deformation at elevated temperatures, the stress–strain curve presents hysteresis loops, and the area of the hysteresis loop increases gradually with continuous cyclic loading and sustained loading times. Intergranular and transgranular cracks in the microstructure accelerate the CGI alloy fracture failure. The fatigue life is sensitive to the short loading time and decreases with the sustained loading time exponentially under the tension-tension fatigue condition. The short holding time has a great influence on the fatigue life of CGI. The fatigue behavior of CGI alloys and the influence of holding time on the fatigue life can be characterized by y = aexp(bx) (a and b are constants, can be fitted through the test data). In addition, the fatigue life of CGI alloy can be predicted by the ductility depletion method. But the equivalent stress amplitude needs to be modified to eliminate the effects of oxidation damage.

High-accurate FE simulation on compressive behavior of steel cruciform column with welding imperfection

Due to its various advantages, welding is commonly used in the construction for steel connection. However, the local temperature difference in the welding causes welding deformation and residual stress. The welding deformation and residual stress can significantly impact the load-bearing performance of members. Therefore, it is important to evaluate those behaviors with high precision. In the previous studies, thermal elastic-plastic analysis was used to evaluate welding deformation and residual stress in simulated welded specimens and the compressive simulation was applied to obtain, for example, the load-bearing performance. Nevertheless, there are limitations in assessing structures made up of thin plates. This is because the simulation of welding is typically modeled using solid elements, while the simulation of loading analysis uses shell elements. As a result, these analysis steps are not directly related, leading to deficiencies in the evaluation process. In this study, the solid element model and shell element model were modeled to simulate the welding deformation and residual stress. The corresponding load-bearing capacity results obtained from the continuous loading analysis were compared with the results from experiment to verify the consistency. According to the results, shell models that perform welding analysis simulation followed by continuous compressive analysis are better able to replicate experimental results in terms of out-of-plane deformation and maximum load-carrying capacity under compressive analysis. This is in contrast to solid models, which fall short in reproducing the same results. Moreover, the shell model is also more efficient than the solid model in terms of time saved during analysis and calculation.

Dynamic damage evolution of bank slopes with serrated structural planes considering the deteriorated rock mass and frequent reservoir-induced earthquakes

To investigate the dynamic damage evolution characteristics of bank slopes with serrated structural planes, the shaking table model test and the numerical simulation were utilized. The main findings indicate that under continuous seismic loads, the deformation of the bank slope increased, particularly around the hydro-fluctuation belt, accompanying by the pore water pressure rising. The soil pressure increased and then decreased showed dynamic variation characteristics. As the undulation angle of the serrated structural planes increased (30°, 45°, and 60°), the failure modes were climbing, climbing-gnawing, and gnawing respectively. The first-order natural frequency was used to calculate the damage degree (Dd) of the bank slope. During microseisms and small earthquakes, it was discovered that the evolution of Dd followed the “S” shape, which was fitted by a logic function. Additionally, the quadratic function was used to fit the Dd during moderately strong earthquakes. Through the numerical simulation, the variation characteristics of safety factors (Sf) for slopes with serrated structural planes and slopes with straight structural planes were compared. Under continuous seismic loads, the Sf of slopes with straight structural planes reduce stalely, whereas the Sf for slopes with serrated structural planes was greater than the former and the reduction rate was increasing.

Yoğun Bakım Hastalarında Antimikrobiyal İlaç Dozajlarının Uygunluğunun Değerlendirilmesi

The purpose of this study was to investigate the factors that required dose adjustments of antimicrobial drugs in intensive care unit (ICU) patients and to identify the drugs that required the most dose adjustments.
 The 26-bed reanimation ICU of a university-affiliated hospital hosted this study from September to December 2022. Two clinical pharmacists on duty examined patients' antimicrobial drug dosages daily. The acceptance status of the recommendations and the patients' demographic information were recorded.
 The study involved 133 ICU patients, and antimicrobial drug recommendations were made for 48 patients, 31 (64.6%) of whom were male. The median (IQR) age of the 48 patients was 67 (54–77). The number of recommendations was 94, and all of them were accepted by the physician. The recommendation rates according to the causes were: inappropriate dosages based on renal functions (71.3%), presence of continuous renal replacement therapy (11.7%), indication (10.6%), body weight (4.3%), and loading dose (2.1%).
 The top 3 drugs for which recommendations were made the most were colistin (21.3%), meropenem (18.1%), and piperacillin-tazobactam (12.8%). The most troublesome drug was colistin, which is frequently used to treat Acinetobacter pneumonia. Clinical pharmacist and physician collaboration may help rationalize ICU antimicrobial drug use.

Re-Analysis of Historical Data and Model Calibration of Duration of Load Effect on Structural Timber

The duration of load (DOL) effect in structure timber refers to the degradation of strength and stiffness that occurs under long-term continuous loading. This paper investigated the DOL effect in structure timber using DOL tests and DOL damage models. Based on the empirical-fitted formulae, the DOL coefficients were derived for three long-term sustained loads in bending, tension perpendicular to grain, and shear parallel to grain, and the results were compared and analyzed with the Madison equation, Gerhards model, Nielsen model, and Foschi and Yao model derivations to verify the applicability of the DOL empirical model and the three DOL damage models. The results show that based on the historical data of the DOL tests, the Madison empirical formula was found to be better applied to the derivation of DOL coefficients under the bending and tension perpendicular to grain long-term sustained loading, and the derivation of DOL coefficients under shear loading is not satisfactory. Among the three DOL damage models, the Foschi and Yao model was better than the Gerhards and Nielsen models for fitting the DOL test results under bending, tension perpendicular to grain, and shear parallel to grain. The DOL coefficients derived based on the Foschi and Yao model are more comparable to test results and resemble those derived from the Madison formula.

In situ investigation of the evolution of shear transformation zones with different elastic tensile strains in metallic glass

Shear transformation zones are usually thought as the fundamental unit characterizing microscopic atomic rearrangement motion during deformation in amorphous materials and the corresponding evolution process determines the macroscopic mechanical behaviors. However, the evolution process of shear transformation zones under tensile loading are difficult to be experimentally detected. Here, one in-situ tensile platform coupled with nanoindenter was introduced to conduct a series of nanoscale continuous loading and creep tests on Cu50Zr50 metallic glass film under different pre-tensile strains within the elastic deformation region. The effects of loading rate and pre-tensile strain on the continuous loading and creep behaviors were systematically investigated. Moreover, the corresponding shear transformation zone volume, the activation volume and the relaxation time spectrum during tensile deformation were determined based on the Cooperative Shearing model and Maxwell-Voigt model. It was found that both of the shear transformation zone volume, activation volume and the peak intensity for the relaxation time spectrum increase with pre-tensile strain. Finally, one scheme is proposed to illustrate the microscopic mechanism for the evolution of shear transformation zones during tensile deformation. The current study offers one effective experimental strategy to in-situ investigate the mechanical behaviors and to reveal microscopic deformation mechanism in amorphous materials.

Thermo-elasto-hydrodynamic analysis of a specific multi-layer gas foil thrust bearing under thermal-fluid–solid coupling

Gas foil bearing faces severe and complex thermal-fluid–solid coupling issues when in ultra-high speed and miniaturized impeller machineries. In this study, a Thermo-Elasto-Hydrodynamic (TEHD) analysis of a specific multi-layer gas foil thrust bearing on the continuous loading process within a steady rotational speed is numerically investigated by a three-dimensional thermal-fluid–solid coupling method. Results indicate that the multi-layer foil exhibits nonlinear overall stiffness, with the thrust bottom foil serving as the primary elastic deformation structure, while the thrust top foil maintains a well-defined aerodynamic shape during a loading process, which helps reduce frictional damage and achieve an adequate loading capacity. For low loads, the fluctuation of the gas film is extremely sensitive, and it weakens dramatically as the load increases. The viscous heating and friction torque exhibit a linear relationship with an increasing bearing load after a rapid growth. Depending on the exact stacking sequence and contact position of the multi-layer gas foil, the overlapping configuration allows for efficient transfer of viscous-shearing heat accumulated at the smallest air film through thermal conduction while providing elastic support. Due to the strong inhomogeneity of the viscous heat under varying loads, the temperature distribution on the top foil surface shows pronounced variations, while the difference between the peak and average temperatures of the thrust plate and top foil surfaces widens substantially with an increasing load.

Microstructural evolution and mechanical behaviors of the third–generation automobile QP980 steel under continuous tension and compression loads

As one of the representatives of the third–generation automobile steel, QP980 is a high–quality material for the improvement of automobile lightweight and crash safety. In this paper, tension and compression tests are conducted for the QP980 steel based on a self–designed testing platform. Microstructural evolution and mechanical behavior under monotonic and continuous tension/compression loads are investigated. The results show that the martensitic transformation in QP980 steel is more easily excited in the monotonic tension state than in the monotonic compression state. In the tension–compression–tension (T–C–T) and compression–tension–compression (C–T–C) modes, the Bauschinger effect of QP980 depends on the pre-strain amount and the pre–strain mode. The Bauschinger effect is stronger at a higher pre–strain. It is also stronger in T–C–T than in C–T–C because the transformation of retained austenite after T–C–T is greater than that after C–T–C. By analyzing the hardening and softening behaviors in the forward, reverse and reforward loading branches of T–C–T and C–T–C, the hardening ability during reverse and reforward loading branches is higher than that during forward loading. Permanent softening occurs between reverse loading and forward loading of T–C–T instead of C–T–C. The research result of this paper is favorable for understanding the relation between mechanical behavior and microstructural evolution of QP980 steel under the condition of complex loads, and promote its large–scale application.

Deformation and Force Chain of Two-Dimensional Granular Systems under Continuous Loading.

A continuous loading experiment of a two-dimensional granular system was carried out and the experimental data were obtained by digital image correlation (DIC). The deformation field of the granular system and the changing laws of the deflection angle and coordination number of the granules on force chains with time were obtained. Based on the granule element method, the quantitative calculation of contact force was realized, and the internal force chains of the granular system were identified. The effects of contact force between granules and mechanical parameters on the evolution of force chains in a two-dimensional granular system under line loads were analyzed. The formation, evolution, and reconstruction of force chains in a granular system during loading, as well as the influence of the force chain network evolution on the macroscopic mechanical properties of granules were discussed. The experimental results indicated that the evolution of force chains was directly related to the number, geometric properties, and permutation distribution of granules in direct contact with the external load.

3D printing a tear-resistant conductive organogel used for wearable sensor

In recent years, ion conductive hydrogels based on photocurable 3D printing technology have attracted wide attention in the application of wearable sensors, which greatly simplifies the manufacturing process of devices, while making devices with high sensitivity and high fidelity. However, the current ionic hydrogel network via photocuring 3D printing is mainly crosslinked by covalent bonds. Due to the lack of sufficient energy dissipation and high-functionality cross-links within the network, the gel will inevitably crack after continuous dynamic loading. Here, we designed an organic gel with excellent tear resistance, which is mainly attributed to the high-functionality cross-links constructed by nano-clay containing a large number of hydroxyl groups. Specifically, the precursor of the organic gel is mainly composed of N-methylol acrylamide (NAM), nano-clays, photoinitiator, and water-glycerol binary solvent system. After photocurable printing, lots of hydrogen bonds are formed between nano-clays and poly-NAM network, which not only provides an energy dissipation mechanism for the gel network, but also acts as a nanoscale cross-linking site to resist crack propagation during the stretching of the gel. Under the action of nano-clay, the tear resistance of the gel has been greatly improved. In addition, the sodium ions released by the nano-clay ensure the good ionic conductivity of the gel, verifying its potential as a strain sensor with high sensitivity. What's more, combining skin-like organic gels and 3D printing technology enables the manufacture of highly sensitive sensors much easier and more designable. This study not only provides a method for the preparation of high-precision ionic conductors with excellent tear resistance, but also clears the way for developing a new class of wearable devices and intelligent electronics.

Osteopontin Upregulation, Induced by the Continuous Mechanical Load in Adipose Tissue-Derived Mesenchymal Stem Cells, is Strongly Restricted in INF-γ/TNF-α/IL-22 Microenvironment.

The osteogenic potential of mesenchymal stem cells (MSc) in axial spondyloarthritis (AxSpA) depends on the interplay of inflammation and multiple hormonal and local mechanical factors. In this study, MCs, derived from the adipose tissue of a healthy donor, were cultured under or without continuous mechanical load in the osteogenic differentiation medium with or without the addition of testosterone, cocktail of INF-γ/TNF-α/IL-22, or both. Real-time PCR for osteogenic transcription factors demonstrated that in the absence of INF-γ/TNF-α/IL-22, mechanical load causes significant upregulation of SPP1 (osteopontin), while the presence of the inflammatory cytokines almost completely abolishes this effect. In addition, exposure to INF-γ/TNF-α/IL-22 slightly upregulated BMP2, but suppressed the expression of ALPL, Col1A1, and SPP1, reinforcing the hypothesis that the inflammatory environment allows MSc to commit toward the IL-22-driven osteogenic differentiation butcan restrict the later stages of osteogenesis. In summary, osteopontin can play a role in the pathogenesis of AxSpA, linking between mechanical load and pathological bone formation.

A Systematic Analysis of Infinite Scrolling in Digital Interfaces: A Good Accompanied by Bad and Ugly

In the digital age, user interfaces play a pivotal role in shaping user experiences and determining the success of websites, applications, and social media platforms. Infinite scrolling has emerged as a widely adopted feature, transforming the way users interact with and consume content. This paper presents a systematic analysis of the implications, advantages, and drawbacks of infinite scrolling in various digital interfaces. By amalgamating insights from existing literature and examining interface design principles, this study seeks to provide a comprehensive understanding of the impact of infinite scrolling on user behaviour and interface performance. The analysis commences with an exploration of the psychological and behavioural aspects of infinite scrolling. In understanding user engagement, attention span, and content consumption patterns, this research aims to uncover the psychological mechanisms that make infinite scrolling captivating and encourage users to explore content for extended durations. Studies have shown that infinite scrolling can create a sense of fluidity and continuity, enticing users to stay engaged for longer periods and discover more content than traditional pagination or load more button approaches. This seemingly infinite supply of information aligns with the human desire for novelty and curiosity, which contributes to increased user retention. In addition to user-centric aspects, this analysis addresses the technical implications of infinite scrolling. Infinite scrolling introduces dynamic content loading, which can impact website performance and data handling. As users scroll through large volumes of content, the continuous loading of data can lead to slower page loading times, potentially resulting in frustration and abandonment. Moreover, search engine optimization (SEO) can be affected, as infinite scrolling may hinder search engines' ability to index and rank content accurately. Developers and designers must consider these technical challenges and adopt optimization techniques to ensure a smooth and efficient user experience. International Journal of Scientific Research in Engineering and Management (IJSREM) Volume: 07 Issue: 07 | July - 2023 SJIF Rating: 8.176 ISSN: 2582-3930 © 2023, IJSREM | www.ijsrem.com DOI: 10.55041/IJSREM24808 | Page 2 Despite its allure and benefits, this systematic analysis also unveils several drawbacks associated with infinite scrolling. The never-ending content flow can lead to increased cognitive load, making it harder for users to retain information or recall previously viewed content. Additionally, infinite scrolling may present accessibility challenges for users with disabilities, as they may find it difficult to navigate and locate specific information without clear navigation cues. In conclusion, this systematic analysis provides a comprehensive understanding of the impact of infinite scrolling on user behaviour, satisfaction, and technical considerations. By synthesizing existing knowledge and offering practical recommendations, this research contributes to the ongoing discussion about the role of infinite scrolling in shaping the future of digital interfaces. As technology continues to evolve, informed decision-making and user-centric design will remain pivotal in leveraging the advantages of infinite scrolling while mitigating its drawbacks to create more enjoyable and accessible digital experiences. Keywords: Infinite Scrolling, Digital Technology, Content, User Behaviour

Experimental Study of a Biomechanical Behaviour of Rat Patellar Tendon

Tendon is important structure of the human body, since it can sustain tensile loading. The primary function of this tissue is to stabilize the joints they attached to it during daily activities. As well as, tendon has viscoelastic properties that can determine their response to loading and restrict the potential of injuries. One of the major points that this paper works with is the study of the biomechanical behaviour of tendon in response to tensile loading to describe their biological behaviour. Also, conclude the mathematical expression that may illustrate the tendon behaviour. All of the experiments were made in Physiology laboratories / Medical College/ Al- Nahrain University on ten rats "Rattus Norvegicus" of [108- 360] gm weight for in- vitro tensile test. So that 20 specimens were dissected from the rat knees, for the patellar tendons which always hydrated to prevent the tissue dryness. The results of the study, shows the behaviour of the tendon in response to tensile loading with two techniques; the dead loads technique and the continuous loads technique. The stress- strain relationships were also evaluated, as well as, the modified superposition theory was applied at different strain levels to the patellar tendon. The obtained results show that the modified superposition theory gives good results that are partly similar to the experimental results. Also, the tendon shows longer initial pattern than that for the ligament due to the presence of higher elastin content in the tendon than in the ligament.

Multi-type dynamic load identification algorithm in continuous system: A numerical and experimental study based on SSM-Newmark-β

Dynamic load identification based on structural responses is an important problem in the field of engineering and plays an important role in the condition assessment of mechanical structures. Current popular load identification methods such as the state-space method (SSM) and the Green's kernel function method (GKFM) are implemented on discrete systems with outstanding performance, but when dealing with complex continuous systems, there are some limitations such as low efficiency and inaccuracy. In this paper, a continuous system load identification algorithm based on SSM and Newmark-β is proposed for the first time. Using modal coordinate transformation and modal truncation methods, the number of infinite vibration differential equations of a continuous system in physical space are converted to a finite number of vibration differential equations in modal space, where the modal truncation order and the optimal layout of the sensors are combined by modal strain energy. The Newmark-β method in modal space is derived and thus combined with SSM to obtain a load identification model Y=HF called SSM-Newmark-β method, which reduces the size of the transfer matrix H. The solution time of the proposed algorithm is 0.38 s for continuous systems, which is rather shorter than that for discrete systems. Furthermore, the simulations show that it has better accuracy and noise immunity than SSM and GKFM in the identification of sinusoidal load, impact load, and random load. The effect of time step is also discussed which reveals that the larger time step has less effect on the proposed algorithm. An experimental study is carried out on a cantilever beam system. The result verifies that the SSM-Newmark-β algorithm has better accuracy in load identification for the continuous system. This research provides a new sight for the real-time identification of dynamic loads for complex structures.

Effect of different loading conditions on corrosion fatigue crack growth rate of a nickel-based alloy in supercritical water

Advanced ultra-supercritical (A-USC) technology improves the initial steam temperature to 650 °C and more. In such an extremely corrosive medium environment, metallic materials are susceptible to corrosion fatigue. In the present study, the aim is to evaluate the effect of maximum stress intensity factor (Kmax), stress ratio (R), waveform, frequency, and holding time (th) on the corrosion fatigue cracking behavior of C-HRA-2 (a candidate nickel-based alloy for A-USC units) in supercritical water (650 °C/25 MPa). The results show that with the increase of Kmax, the corrosion fatigue crack growth rate (CFCGR) increases and satisfies the exponential relationship. The decrease in R and frequency both cause the rise of CFCGR, which satisfies the logarithmic linear relationship. Sinusoidal and triangular wave loading have no significant effect on the CFCGR. Trapezoidal wave with th has a larger CFCGR while with the rise in th, the CFCGR increases. The crack propagation path is straight, perpendicular to the loading direction, and secondary cracks are also observed. Transgranular and intergranular mixed fractures occurred during continuous loading. The proportion of intergranular fracture increases significantly as holding time is applied. The corrosion fatigue crack growth of C-HRA-2 in supercritical water can be explained by dynamic embrittlement mechanism.

Experimental verification of high-performance polymer gears in an electric vehicle powertrain

AbstractGears made of polymers increasingly gain relevance in current research and industrial practice. Due to their advantages such as low density and the possibility of cost-efficient production in large quantities, more and more efforts are made to substitute steel gears with polymer wherever possible. However, the usage of polymer gears in current vehicle systems is still almost exclusively limited to applications with restricted power transmission, like actuators. To extend the field of application to power transmissions as well, in this study a transmission was developed for the usage in a small electric vehicle of the 7Le power class considering the application of polymer gears. Compared to the serial transmission, one of the gear stages was completely substituted with polymer gears. The load-carrying capacity of the newly designed hybrid polymer-steel transmission was investigated for functional verification on a specially developed test rig as well as inside a modified demonstrator vehicle under real-life conditions. Assuming usual operating conditions, the load-carrying capacity of the polymer gears appears suitable for the aimed application on the test rig as well as inside the demonstrator vehicle. Moreover, with increased power and under continuous sustained loading, high performance of the polymer stage as well as a stable temperature behavior can be observed. Under the given circumstances, polymer gears can be used as part of a powertrain in small electric vehicles.

Обоснование выбора материала для изготовления ножа исполнительного органа геохода

Introduction. The use of geohods for the development of underground space is an innovative approach, the essence of which is the use of geo-media in the rock mass to create traction forces. The constructive and functional requirements for the working bodies are being developed, which take into account the nature of the movement and functionally constructive differences, the formation of a specific form of slaughter obtained during the operation of the working body, in which the working body is made in the form of helicoids shape. To implement technological solutions, it is necessary to select and justify the materials of the working body of the geohod. Materials and methods. The paper considers the basic requirements for the materials of the working body of the geohod, based on the structural, functional and technological features of the design of the geohod. The paper notes that the cutting edge of the working works in particularly harsh conditions, therefore, materials such as alloy steels with high wear resistance are recommended for this type of construction. Foundry alloy steels and high-strength alloy alloys are considered as rational options. Research results and their discussions. Taking into account the features of the equipment, the physical and mechanical properties of the rock being destroyed, the strength characteristics of the recommended materials and their technological properties, when choosing materials, emphasis is placed on the mechanical properties of materials and wear-resistant properties, which are important parameters, since abrasive wear of the working surfaces occurs when the working body of the geohod. Conclusion. The recommended alloyed alloys with high strength meet all the requirements that are imposed on the design of the knife of the executive body, but do not meet the technological requirements, namely, they are quite difficult to deform, difficult to process by cutting and welded. Considering all the technological properties that are significant in the implementation of the manufacturing technology of the working body of the geohod, it is recommended to choose more durable materials that withstand large continuous loads. Resume. The article presents the results of research to determine the choice of material for the manufacture of the working body of the geohod. It is established that for the manufacture of the working body, when using the casting technology of production, steel 30ХГСА can be used, when processing pressures – steel 18Х2Н4МА. Suggestions for practical application and direction of future research may be useful for the development of manufacturing technology of the main elements of the working body of the geohod.