Composite Grid Research Articles

The Influence of North Atlantic Dipole Sea Surface Temperature Anomalies on Autumn Drought Over Southwest China

ABSTRACTIn recent decades, there has been a notable increase in the frequency and severity of drought events in Southwest China (SWC), which have significantly impacted agriculture and the social economy. Using sea surface temperature (SST) data from the Hadley Centre, daily meteorological drought composite index grid data and ERA5 reanalysis data, we investigate the characteristics of autumn drought in SWC and discuss its possible causes using empirical orthogonal function (EOF) analysis. The results indicate a distinct ‘Northeast–Southwest’ dipole pattern of autumn drought over SWC in the past decade, which we define as the ‘Chuan‐Yu’‐type drought. A British–Okhotsk Corridor (BOC) pattern Rossby wave train, presenting over Eurasia, is identified as the key factor influencing the ‘Chuan‐Yu’‐type drought in SWC during the autumn. The BOC‐pattern Rossby wave train not only obstructs water vapour transport channels in SWC but also induces anomalous descending motions in the lower to middle troposphere over the region, leading to high temperatures and insufficient precipitation. Further investigation reveals that North Atlantic dipole SST anomalies trigger the BOC‐pattern Rossby wave train in autumn. The results of the linear baroclinic model sensitivity simulations support the above conclusion. These findings will make valuable contributions to autumn drought prevention and mitigation in SWC.

Multistable Composite Laminate Grids as a Design Tool for Soft Reconfigurable Multirotors

Adaptive‐morphology multirotors exhibit superior versatility and task‐specific performance compared to traditional multirotors owing to their functional morphological adaptability. However, a notable challenge lies in the contrasting requirements of locking each morphology for flight controllability and efficiency while permitting low‐energy reconfiguration. A novel design approach is proposed for reconfigurable multirotors utilizing soft multistable composite laminate airframes. These airframes show kinematically determinate morphologies corresponding to multiple minima in their elastic potential energy landscape. By varying design parameters, the methodology allows for tuning the energy landscape characteristics governing each morphology's structural stability and reconfiguration energetics. The airframe, composed of multistable composite laminate grids, is optimized to maximize rigidity under flight loads and minimize reconfiguration work. The 130‐g reconfigurable multirotor design demonstrates self‐locking properties in an open and a folded configuration, enabling a 48% reduction in width‐span without compromising stability during flight. Soft pneumatic actuators, actuated using a tethered compressed air supply, enable reversible reconfiguration on the ground between open and folded configurations. The design resolves the conflicting requirements of high‐stiffness to lock each flight configuration and low‐actuation work for reconfigurability. By exploiting soft yet multistable structures, the approach combines the stability observed in rigid‐linked reconfigurable multirotors with the low‐effort reconfigurability of soft multirotors, offering new methods for designing adaptive‐morphology multirotors.

Experimental and numerical investigation of energy absorption in honeycomb structures based on lozenge grid unit cells under various loading angles

The present study aims to numerically and experimentally analyze the energy absorption characteristics of honeycomb structures using Lozenge grid unit cells made from continuous glass fibers reinforced polylactic acid (PLA). The design and load-bearing capability of the Lozenge grid was also examined under different orientations angles. The composite grids were also subjected to heat treatment after the tests, at 70 °C, in order to measure its effect on the energy absorption capacity. The Lozenge grid specimens were additively manufactured using fused filament fabrication. The mechanical properties and failure models were described using the VUSDFLD subroutine in order to simulate the Lozenge structure under quasi-static compressive load. The results revealed a good correlation between the numerical and the experimental values. Moreover, Lozenge grid unit cells based structures at 0 or 90° was found with the highest energy absorption capacity. Meanwhile, the least energy absorption was seen at 45°. Overall, the structures had much higher energy absorption capacity at angles closer to 0 and 90°. Outcomes from this work is aimed toward understanding the damage tolerance of Lozenge lattices, and hence the reliability of such new emerging lightweight structures.

Impact of Extreme Rainfall on High-Speed Rail (HSR) Delays in Major Lines of China

Abstract Punctuality monitoring and analysis aim to optimize resource allocation for enhancing rail traffic performance and quality. Adverse weather conditions, particularly heavy precipitation events, are recognized as significant drivers of delays and reduced punctuality of the rail system. This study addresses two key research questions using high-speed rail (HSR) as an example—what is the impact of rainfall on HSR’s delay and to what extent are HSR vulnerable to rainstorms. The data for the study were collected from the HSR on the major lines of eastern China in the rainy season of 2015–17 which lasted from May to October. High-resolution precipitation data are integrated with nonspatial HSR operational data using GIS to create composite grids covering buffer zones around HSR lines. These grids match the spatial scale of historical hourly precipitation data and enable regression analyses to assess how precipitation affects HSR operations. The results indicate that extreme rainfall significantly contributes to delays and reduced punctuality, with varying impacts observed across different HSR lines. Specifically, daily areal precipitation significantly delays services on the Hangzhou–Shenzhen and Nanjing–Hangzhou HSR lines. Rainfall intensity has a more pronounced impact on delay services of the Beijing–Shanghai HSR, while extreme precipitation most frequently affects the Shanghai–Nanjing and Jinhua–Wenzhou HSR lines. The case analysis enhances understanding of HSR vulnerability to heavy rainfall conditions and recommends regional adaptation strategies to manage climate-related uncertainties.

Advancing infrastructure resilience: A polymeric composite reinforcement grid with self-sensing and self-heating capabilities

In this study, a novel multifunctional grid-shaped polymeric composite (MGPC) with reinforcing, autonomous strain, stress, and damage sensing and localizing in addition to targeted heating capabilities, has been developed. Distinct from preceding composites, this grid synthesizes these features collectively for the first time and concurrently addresses current challenges in multifunctional composites, such as environmental impact, data reliability, complexity, and production costs. The fabrication process entails 3D printing an electrical circuit with conductive filaments within a polylactic acid (PLA) host polymer. The conductive filament was composed of a thermoplastic polymer (TPU) infused with carbon nanotubes (CNT)-grafted carbon fibres (CFs) produced via chemical vapour deposition. The mechanical, microstructural, and electrical properties of the grid elements and cementitious slabs reinforced with MGPC were comprehensively examined. The MGPC's performance in traffic flow monitoring, mechanical behaviour prediction, and damage localization was assessed through wheel tracking, asymmetric punch tests, piezoresistivity response evaluation, and digital image correlation techniques. Furthermore, the self-warming ability of the MGPC in cementitious composites was investigated using different voltages. The extruded TPU containing CNT-grafted CFs exhibited an electrical percolation threshold of approximately 5.0 wt%, resulting in a conductivity of around 70 S/m for the filaments. Incorporating MGPC as reinforcement within cementitious composite slabs led to notable enhancements, with flexural strength increasing by approximately 15 % and failure strain by up to 350 %. Wheel tracking tests revealed changes in the electrical: 5.8 % for 520 N and 7.8 % for 700 N wheel loads, with roughly 5.0 % average error in velocity detection. Transverse elements precisely detected wheel locations demonstrating the MGPC capabilities in accurately detecting wheel speed weight, and location. The study established strong correlations between electrical resistance changes, mechanical behaviour, and damage detection, affirming the MGPC's reliability and efficacy for damage monitoring and localization. The cementitious slab reinforced with MGPC reached around 52°C through a 20 V direct current, with a heating rate of 0.25°C/s and a power density of 142 W/m², showing its potential for practical applications such as self-healing and de-icing. However, design parameters such as mesh and conductive circuit configuration, long-term performance, as well as Life Cycle Assessment need further investigation.

Upcycling of Used Cotton Cloth to Robust Fire-Resistant Carbon Composite Grids with Excellent EMI Shielding

Upcycling of Used Cotton Cloth to Robust Fire-Resistant Carbon Composite Grids with Excellent EMI Shielding

Early Holocene inundation of Doggerland and its impact on hunter-gatherers: An inundation model and dates-as-data approach

Sea-level rise was a key factor changing environments during the Early Holocene in Northwest Europe. It affected Mesolithic hunter-gatherer communities by inundating large areas in the current North Sea, commonly referred to as Doggerland. In this paper we present novel inundation models for the southern North Sea providing visualisations of lateral inundation driven by sea-level rise and relate it to frequency analysis of radiocarbon dates from archaeological sites. These improve on previous studies that relied on bathymetric data, which includes post-inundation overprints of Holocene sedimentation and erosion, and thus significantly underestimates the timing of inundation in some areas.We constructed a paleoDEM (a composite elevation grid of the top of the Pleistocene) for the eastern part of the southern North Sea; and sea level surfaces that combine relative sea-level curves from glacio-isostatic adjustment models optimised for Britain and southern Scandinavia respectively. We corrected our paleoDEMs for tectonic background basin subsidence, and in the inundation modelling account for pre-compaction elevation of peat in coastal areas. We evaluated the impact of these model components on our results and describe the possible inundation history of Doggerland. We suggest earlier inundation than predicted by previous models, showing significant area loss around 10.5–10 ka cal BP.Palaeogeographic changes are compared with archaeological radiocarbon data using a dates-as-data approach. Composite Kernel Density Estimate and permutation tested Summed Probability Distributions are used as a proxy for the visibility, nature and intensity of human activity. Results indicate key periods of growth and decline recorded in the dataset, as well as regional differences in growth rate, some correlating with inundation phases. Chiefly, we find elevated growth rates around 10.5–10 ka in northwest Germany and the Netherlands, contemporaneous with the abovementioned phase of extensive area loss, and moreover, with changes in culture and practices on Early Mesolithic sites.However, the spatiotemporal distribution of archaeological data is significantly influenced by accessibility and preservation of sediments of a certain age. We discuss the importance of inundation modelling and sediment data in understanding how landscape taphonomy affects archaeological patterning, especially in dates-as-data approaches.

Study on preparation and property of coir fiber reinforced epoxy resin composite geogrid

Based on the development and application of green composite building materials, this study prepared a coir fiber reinforced epoxy resin composite grid using coir fiber as the reinforcement material. Through tensile tests of a multi rib grid, the effects of coir fiber content, length, and rib spacing on the composite grid were studied. The results showed that with increase in the coir fiber content, the tensile yield force first increased and then decreased, reaching the maximum value at coir fiber content of 1%. When the coir fiber content exceeded 1%, the tensile properties of the composite grid were lower than that of pure epoxy resin. With the increase in the coir fiber length, the tensile yield force of composite grid also first increased and then decreased. At a fiber length of 1 cm, the maximum tensile yield force was obtained, which was 34.33% higher than that of pure epoxy resin grid. Compared with the influence of fiber length and content on the composite grid, the influence of rib spacing on the composite grid was more obvious. At a rib spacing of 1 cm, the tensile yield force reached its maximum.

High‐velocity impact resistance of the carbon fiber composite grid sandwich structures

AbstractThe carbon fiber composite grid sandwich structure represents an innovative category of lightweight composite sandwich structures, showcasing remarkable attributes including reduced weight, high‐specific strength, exceptional specific stiffness, and robust design flexibility. Using ABAQUS, the high‐velocity impact performance of carbon fiber composite grid sandwich structure is numerically simulated. This study delved into examining the impact patterns arising from various factors, including the equivalent density, height, and geometric configuration of the core layer. Additionally, the effects of the impact punch's initial velocity, size, and impact position on the high‐speed impact resistance performance of the carbon fiber composite grid sandwich structure were explored. The fracture absorption work of the structure and the kinetic energy attenuation rate of the impact punch are positively correlated with the equivalent density, height of the structural core layer, as well as the initial velocity and dimensions of the impact punch. Notably, the square carbon fiber composite grid sandwich structure was most significantly influenced by the equivalent density of the core layer, while the mixed carbon fiber composite grid sandwich structure was most sensitive to variations in core layer height and punch size. When impacted at the intersection of the ribs, compared with the central position between the two ribs, the structure shows enhanced fracture absorption energy and greater impact kinetic energy attenuation rate.Highlights The structure was modeled based on the interlocking assembly process. The high‐velocity impact resistance of the structure was studied. Different structural parameters were designed for the core layer to study. The initial velocity, size and impact position of the punch were involved.

Mechanical properties of flax fibers as a green alternative for FRCM systems

In recent years, thanks to policies oriented toward the rehabilitation of existing heritage and the introduction of more environmentally sustainable choices, an increased attention has been devoted to the study of new structural strengthening solutions. With reference to masonry buildings, which constitute a significant part of the built heritage, Fiber Reinforced Cementitious Matrix (FRCM) systems are widely adopted to achieve more effective structural capacity, making use of inorganic matrices and composite grids, the latter being formed of carbon, basalt, glass, or aramid fibers. However, the necessity to reduce the carbon emissions, also considering the new European perspectives on sustainability, have prompted the scientific and engineering community to explore eco-friendly alternatives. In this context, the use of natural fibers as potential alternatives for enhancing the structural performance of a building or part of it, rises as a promising area of study. The present study proposes an analysis on the use of flax fibers within FRCM systems, aimed at reinforcing masonry structures. The mechanical and durability properties of the material are investigated through tensile tests on flax yarns, as well as tests on a fabric composed by flax bundles supported by a mesh of glass fibers. The results obtained in this study shaw how the natural type of fiber studied is so interested when it is treated with coating in terms of mechanical properties and durability.

Long-term shear performance of concrete beam with carbon fiber-reinforced composite grid stirrups under sustained loadings and seawater immersion

Using carbon fiber-reinforced composite (CFRP) grid stirrups to replace traditional steel stirrups in reinforced concrete (RC) beams can effectively improve the corrosion resistance of structures in marine environments. In this study, the durability of RC beams with CFRP grid stirrups under the coupled effects of sustained loads and immersion in seawater was studied. The sustained loads were set at 24% and 48% of the ultimate bearing capacity of the RC beam, and the specimens were immersed in artificial seawater at room temperature for 90 days, 180 days, and 360 days, respectively. The crack load and shear capacity of the beam were measured at the scheduled time. The initial stiffness of the beam decreased as the immersion time increased, and the higher the sustained load was, the lower the initial stiffness of the conditioned beam. The contribution of the CFRP grid stirrup to the shear load capacity after the cracking load was reached was more significant than that before. The effects of the 48% sustained load on the ultimate tensile strain of the CFRP stirrup were more significant than those for the 24% sustained load. Both immersion and sustained loading improved the cracking load and shear capacity of the beam, and the contribution of sustained loading to the shear capacity decreased as the immersion time and the sustained load level increased. Equations were proposed for predicting the shear strength of RC beams with CFRP grid stirrups under sustained loading and seawater immersion.

Analysis of the seismic vulnerability and innovative retrofit solutions of cavity brickwork walls

This paper offers the results of an experimental investigation aimed at assessing the seismic vulnerability of a type of cavity wall, with a brief discussion of the advantages of this form of construction. Cavity walls were mainly designed to carry vertical loads and to improve the thermal behaviour of the building envelope: these are made of two single-wythe walls (typically using low-perforated bricks) with a cavity filled with a polystyrene panel. Cavity walls often exhibit poor seismic performance. A total of 12 full-size cavity-wall panels were tested in this experimental programme at the laboratory, by conducting shear and bending tests aimed at studying the in-plane and out-of-plane structural responses under simulated seismic actions. In addition, different retrofit solutions were studied and used to reinforce the cavity-wall panels: this included the traditional method to tie the wall leaves with steel connectors, an innovative method made of GFRP (Glass Fiber Reinforced Polymers) rods, and a mortar coating reinforced with a composite grid, known as FRCM (Fiber Reinforced Cementitious Matrix). It was found that the lateral bending-capacity of the panels reinforced with the GFRP rods and a FRCM coating greatly increased over that of the control unreinforced specimens. The proposed reinforced method was able to provide some seismic resisting capacity to the cavity walls, especially against bending and out-of-plane loading, in a more effective way than the traditional method of steel ties.

CO2 emission of polycarboxylate superplasticizers (PCEs) used in concrete

At an annual production of ∼15 million tons, polycarboxylate (PCE) based superplasticizers (cement dispersants) present the most widely used concrete admixture. In this paper, their carbon footprint was quantified considering the three most common kinds of PCE polymers, namely methacrylate ester (MPEG), methallyl ether (HPEG) and isoprenol ether (IPEG) based PCEs produced in four major manufacturing countries: EU-27, US, Japan and China. A cradle-to-gate approach was applied to estimate CO2 emissions from raw materials extraction to PCE fabrication. On this basis, and depending on their chemical composition and country-specific electricity grid CO2 emission factors, their carbon footprints were calculated. The results show a strong dependence on the kind of PCE, their structural design as well as the producing country. For all PCEs, the main components ethylene oxide, unsaturated acids (methacrylic/acrylic acid) and NaOH were found to be mainly responsible for the entire CO2 footprint. The average total CO2 emissions of the three kinds of PCEs vary between 2.98 ± 0.54 kg CO2/kg (MPEG), 2.48 ± 0.48 kg CO2/kg (HPEG), and 2.40 ± 0.47 kg CO2/kg (IPEG). Evidently, MPEG PCEs reveal the highest footprint which is owed to methacrylic acid whereas HPEG and IPEG PCEs contain acrylic acid. The range of total CO2 emissions is caused by significant differences in the carbon footprints of the electrical grids in various countries. An impact study revealed that at common field dosages the contribution of PCEs to the CO2 balance of a standard concrete (CO2 footprint ∼ 300 kg CO2/m3) varies between approx. 3 and 22 kg CO2/m3 in Europe, with ready-mix type PCEs contributing more than precast concrete PCEs. Furthermore, it is demonstrated that the CO2 footprint of PCE superplasticizers can be reduced by almost 80% if predominantly renewable energy is used in the chemical industry.

Seismic behavior of self-restrained grid shear wall with diagonal CFRP-steel composite strips

This paper introduces an innovative structure for a self-restrained grid shear wall with diagonal CFRP-steel composite strips. Steel and CFRP strips are interwoven to enhance the structural integrity of the shear wall. Quasi-static tests are initially conducted on two shear wall specimens with and without diagonal CFRP-steel composite strips. Subsequently, a finite element model is established to represent the self-restrained grid shear wall with diagonal CFRP-steel composite strips. This model is helpful for exploring the influence of composite strips arrangement on the performance of shear walls. Furthermore, a prediction formula is developed to estimate the load-bearing capacity of the CFRP-steel composite strips grid shear wall. The test results show that the yield bearing capacity, ultimate bearing capacity, stiffness and energy dissipation capacity of the specimens increase by 46.6%, 58.2%, 43.6%, and 16.3% respectively after the replacement of composite strips. In addition, the results of finite element simulation indicate that the diagonal arrangement exhibits the highest efficiency in the use of CFRP materials among three reinforced structural forms-diagonal, spaced, and fully arranged composite strips. This arrangement is also the most economical and has the least adverse influence on the internal forces of the frame columns.

Fabrication of a 3D Printed Continuous Carbon Fiber Composite Grid Stiffened Structure Using Induction Heating.

In aerospace applications, composite grids have been widely utilized to enhance the strength of large thin-shell components. Recently, a growing focus has been on the research of 3D printing continuous fiber-reinforced thermoplastic composites. The 3D printing method offers various advantages over traditional molding processes, including a simpler process, higher material utilization, and lower manufacturing costs. However, the use of 3D printing for manufacturing continuous fiber-reinforced composite structures presents challenges, such as a high occurrence of defects within the structure and insufficient mechanical properties. These limitations hinder its widespread application. To address these issues, this study proposes a method for treating 3D-printed composite grid structures using induction heating. Initially, the induction heating mechanism of 3D-printed composite grids was analyzed by studying the impedance at the junction, including direct contact resistance and dielectric hysteresis loss. Subsequently, the impact of induction heating treatment on internal defects was explored by observing micro morphologies. The results show that the combination of induction heating and vacuum pressure effectively reduces porosities within the 3D-printed carbon fiber composite grids. Additionally, 3D-printed composite grid-stiffened PLA structures were fabricated with induction heating, and the bending and impact tests were conducted to evaluate their mechanical properties. The results indicate that using a grid-unit size of 4 mm leads to significant increases in bending strength and modulus of the grid-stiffened structure, with improvements of 137.6% and 217.8%, respectively, compared to the neat PLA panel. This demonstrates the exceptional mechanical enhancement efficiency of the 3D-printed lightweight composite grids.

Intrinsic Properties of Composite Double Layer Grid Superstructures

This paper examined the opportunities of composite double-layer grid superstructures in short-to-medium span bridge decks. It was empirically shown here that a double-layer grid deck system in composite action with a thin layer of two−way reinforced concrete slab introduced several structural advantages over the conventional composite plate-girder superstructure system. These advantages included improved seismic performance, increased structural rigidity, reduced deck vibration, increased failure capacity, and so on. Optimally proportioned space grid superstructures were found to be less prone to progressive collapse, increasing structural reliability and resilience, while reducing the risk of sudden failure. Through a set of dynamic time-series experiments, considerable enhancement in load transfer efficiency in the transverse direction under dynamic truck loading was gained. Furthermore, the multi-objective generative optimization of the proposed spatial grid bridge (with integral variable depth) using evolutionary optimization methods was examined. Finally, comprehensive discussions were given on: (i) mechanical properties, such as fatigue behavior, corrosion, durability, and behavior in cold environments; (ii) health monitoring aspects, such as ease of inspection, maintenance, and access for the installation of remote monitoring devices; (iii) sustainability considerations, such as reduction of embodied Carbon and energy due to reduced material waste, along with ease of demolition, deconstruction and reuse after lifecycle design; and (iv) lean management aspects, such as support for industrialized construction and mass customization. It was concluded that the proposed spatial grid system shows promise for building essential and sustainable infrastructures of the future.

Upward continuation of total magnetic field intensity data over Sokoto basin, north-western Nigeria

High-resolution aeromagnetic data covering the Sokoto basin, north-western Nigeria were acquired and analyzed using regional enhancement techniques, upward continuation and second order regional. The objective was to delineate major geological structures. The data, which are in form of a grid, were knitted using Oasis Montaj software to obtain the magnetic total field intensity map. The composite grid was reduced to a magnetic equator to align the peaks of magnetic anomalies over the center of their causative bodies. The reduced grid was continued at various planes of observation to understate anomalies due to shallow features. The planes were at 10 km, 20 km, 30 km, 40 km, 50 km, 70 km, and 100 km above the surface. Upward continuation maps produced greatly enhanced the long-wavelength (low wavenumber) anomalies associated with deeper subsurface regional structures. The continuation revealed a high magnetic intensity anomaly in western parts of the area and low magnetic intensity anomalies in the eastern parts. The low magnetic intensity in the eastern part is interpreted as a sedimentary deposit. The residual field was removed from the total magnetic field data using the second-order least square method to get the second-order regional field. The regional field analysis agrees with the upward continuation result.

The Composite Grid Method for Singular Problems of Partial Differential Equations

Partial differential equations are crucial in scientific computing, and this paper will consider some of the problems of partial differential equation singularities. The Composite Mesh Method (CGM) is a new and improved numerical method for solving partial differential equations based on existing numerical methods for finite elements. The method has two meshes over the entire domain—a coarse and a fine set. The two sets of meshes generated by Mesh3 are separate in their respective regions and do not nest or interact. This method improves the accuracy of solving the numerical solution of partial differential equations. This paper discusses the CGM method based on the Finite Element Program Generator (FEPG) and uses it to simulate several singular problems. The numerical simulation results show that the proposed method can obtain more satisfactory simulation results for global problems and use a smaller number of computational generations than the general finite element method.

Influence of the spatial grid type on the result of calculating the neutron fields in the nuclear power plant shielding

The paper considers the influence of the spatial grid type on the result of solving the equation of neutron transport in the nuclear power plant (NPP) shielding. Neutron fields were calculated in a realistic model of a liquid metal cooled fast neutron tank reactor with an integral equipment layout. Structured cubic and unstructured hexahedral grids (pmsnsys and FRIGATE codes) and unstructured tetrahedral and prismatic grids (RADUGA T code) are used. Limiting values of the group fluxes averaged over the material zones for refined grids have been obtained. It has been shown that the calculation results depend on the type of approximation for the curvilinear inner boundaries between the material zones rather than on the grid cell type (cube, hexahedron, tetrahedron, prism). Using “toothed” approximations for curvilinear boundaries leads to an increase in the area of the boundaries, as well as to the neutron flux refraction condition arising on them. These effects lead to an upward bias in the transport equation solution, and for all energy groups. Conclusion. When solving an equation of neutron transport in the NPP shielding by a grid technique, it is necessary to use grids other than leading to “toothed” approximations of the inner boundaries. Tetrahedral or prismatic grids, or grids of arbitrary hexahedrons can be recommended, as well as composite grids in which cubic cells are located inside the material zone, and hexahedron cells are located near the zone boundary.

DIAGRAMMING TECHNIQUES OF PRINTED VS. DIGITAL SCHOOL TEXTBOOKS FOR BASIC EDUCATION IN A PUBLISHING HOUSE OF RIOBAMBA

This study analyzes the techniques used by EDIPCENTRO in the production of the “Mi praxis 4” copy of Language and Literature for the fourth grade of an elementary school in printed and digital versions through composition patterns that identified its graphic level. The inductive, mixed and documentary bibliographic approach was applied, reviewing the school texts later analyzed by technical cards. The composition patterns, diagramming fundamentals and grid elements were examined by comparing the evolution of the didactic material after the pandemic and the change of study modality. In addition, surveys were carried out to students, teachers and parents to know the importance of graphic techniques in those who use the material. The results of the qualitative analysis by means of the matrices indicated that the transition from print to digital school text was performed with better accuracy, improving aspects previously erroneously performed, such as the visual break obtained through the Sophia Platform and preserving other graphic aspects from one version to the other. On the other hand, the statistical data resulting from the surveys showed the reception by the respondents to the school text with a total of 94% of acceptance and reception, allowing to validate the hypothesis statement. In conclusion, the importance of the good execution of diagramming elements in a didactic material was established and confirmed. The change of study modality was based on the aesthetic and functional development of school textbooks, aspects that influence the purchase decision. It is recommended to analyze diagramming techniques in school textbooks of other types, educational or editorial categories in order to associate them with the way they function, using reliable sources for the collection of information.