Span Length Research Articles

Numerical study on the dynamic amplification factors of highway continuous beam bridges under the action of vehicle fleets

The mechanism and reasonable values of the dynamic amplification effect of highway continuous beam bridges under the action of vehicle fleets are quite complex and very unclear at present. This study, using 23 highway continuous beam bridges with the main span lengths from 32 m to 165 m as research objects, investigates the mechanism and influencing factors of the dynamic amplification factors (DAFs) of highway continuous beam bridges under the action of vehicle fleets based on the vehicle-bridge coupled vibration analyses. The results show that the travelling speeds and vehicle intervals (VIs) exert an important influence on the DAFs of continuous beam bridges. The maximum dynamic response at different travelling speeds and VIs is searched in this study, the maximum static response at different VIs is also searched, and their ratio is regarded as the effective DAFs. Based on the calculation results, it is concluded that when the roughness surface condition (RSC) is ‘good’ (or ‘average’), the effective DAFs for the vertical displacement and vertical bending moment at the mid-spans can safely take a value of 1.15 (or 1.30); those for the vertical bending moment at the inner supports and shear force can safely take a value of 1.10 (or 1.20); and when the bridge fundamental frequency is less than 1.0 Hz, all DAF values can take a value of 1.05 (or 1.10). Meanwhile, the relevant provisions in AASHTO LRFD (2017) and CEN (2003) are considered on the safe side when RSC is ‘good’ or ‘average’.

The Effect of Opening Size and Expansion Ratio on the Flexural Behavior of Hot Rolled Wide Flange Steel Beams with Expanded Web

In some design cases, such as in castellated beams, cellular beams, or steel beams with expanded web, it is advantageous to strengthen and enhance the performance of steel beams by increasing the web depth. However, expanding the web of a steel beam is a unique engineering strategy. This modification not only enhances its ability to bear heavy loads but also reduces any bending or flexing while enabling longer distances between supports. The expanded steel beams can be achieved by making a horizontal cutting in the steel beam web and then adding an increment plate (with the same web thickness), called spacer plate, between the two halves of the web sections, thus improving stiffness and strength. To evaluate the behavior of such beams, nine specimens of HEA steel beams with expanded web ratios of 150%, 200%, and 250%, and one specimen as a reference beam, were fabricated. The specimens were evaluated under two-point load over a clear span length of 280 cm. From the experimental work it was found that for steel beams with expanded web that have 18 openings with 80 mm, the beams with an expansion ratio of 150% had the best performance according to load-deflection behavior with a reduction in load capacity by only 11%. Additionally, the beams with expansion ratios of 200% and 250% had no economic viability according to the analysis of load-deflection behavior with a reduction in load capacity by 49% and 62%, compared with the solid expanded steel beam with the same expansion ratio. For the second type of steel beam with expanding web with 9 openings of 160 mm width, the beams with expansion ratios of 200% and 250% were observed to perform better than the first type with a reduction in load capacity by 28% and 50%. Using larger opening width and a smaller opening number is considered the best option for beams with expansion web ratios of 200% and 250%, while on the contrary, using smaller opening width and higher numbers seems to be a better option for beams with 150% expansion web ratio. Expanding the depth of a steel beam provides design flexibility, reduces deflections, and allows for longer spans. These benefits enhance material efficiency and open up new architectural possibilities.

Suppression of Railway Catenary Galloping Based on Structural Parameters’ Optimization

Railway catenary galloping, induced by aerodynamic instability, poses a significant threat by disrupting the electric current connection through sliding contact with the contact wire. This disruption leads to prolonged rail service interruptions and damage to the catenary’s suspension components. This paper delves into the exploration of optimizing the catenary system’s structure to alleviate galloping responses, addressing crucial parameters such as span length, stagger dropper distribution, and tension levels. Employing a finite element model, the study conducts simulations to analyze the dynamic response of catenary galloping, manipulating structural parameters within specified ranges. To ensure accurate and comprehensive exploration, the Sobol sequence is utilized to generate low-discrepancy, quasi-random, and super-uniform distribution sequences for the high-dimensional parameter inputs. Subsequent to the simulation phase, a genetic algorithm based on neural networks is employed to identify optimal parameter settings for suppressing catenary galloping, taking into account various constraints. The results gleaned from this investigation affirm that adjusting structural parameters can effectively diminish the galloping amplitude of the railway catenary. The most impactful strategy involves augmenting tension and reducing span length. Moreover, even when tension and span length are fixed, adjusting other parameters demonstrates efficacy in reducing galloping amplitudes. The adjustment of messenger-wire tension, dropper distribution, and stagger can achieve a 22.69% reduction in the maximum vertical galloping amplitude. Notably, maintaining a moderate stagger value and a short steady arm–dropper distance is recommended to achieve the minimum galloping amplitude. This research contributes valuable insights into the optimization of railway catenary systems, offering practical solutions to mitigate galloping-related challenges and enhance overall system reliability.

Effects of GFRP Stirrup Spacing on the Behavior of Doubly GFRP-Reinforced Concrete Beams

This study investigates the impact of varying glass fiber-reinforced polymer (GFRP) stirrup spacing on the performance of doubly GFRP-reinforced concrete beams. The research focuses on assessing the behavior of GFRP-reinforced concrete beams, including load-carrying capacity, cracking, and deformability. It explores the feasibility and effectiveness of GFRP bars as an alternative to traditional steel reinforcement in concrete structures. Six concrete beams with a cross-section of 300 mm (wide) × 250 mm (deep), simply supported on a 2100 mm span, were tested. The beams underwent four-point bending with two concentrated loads applied symmetrically at one-third of the span length, resulting in a shear span (a)-to-depth (h) ratio of 2.8. The experimental findings reveal that altering the GFRP stirrup spacing along the longitudinal axis of the beams, from 200 mm (equivalent to the effective depth (d)) to 50 mm (equal to (d⁄4)), altered the mode of failure from flexure-shear to flexure-compression. However, when the spacing was equal to or less than (d⁄3), there was no significant improvement in load-carrying capacity, as the contribution of GFRP bars in resisting shear loads was limited. Under service loads, the GFRP-reinforced beams exhibited wider cracks, but reducing the stirrup spacing helped restrain crack widening. Incorporating GFRP bars in the compression zone had a positive effect on reducing crack width in the tension zone. Additionally, using GFRP stirrups with spacing varying between (d) and (d⁄2) in the pure bending region increased the deflection ductility indexes. To enhance the ductility of GFRP-reinforced concrete beams, it is recommended to use GFRP stirrups in the pure bending region with spacing greater than the spacing between GFRP stirrups in the shear spans. The study highlights that the current ACI code overestimates the shear capacity provided by GFRP stirrups, particularly when the spacing is less than or equal to (d⁄3). Doi: 10.28991/CEJ-2024-010-02-011 Full Text: PDF

The Behaviour of Building Frames on Raft Foundation using Dynamic Analysis

When designing building frames for seismic reasons, the effect of soil flexibility is typically disregarded, and the design is executed using the outcomes of dynamic analysis with a fixed base condition. Because the overall lateral stiffness of the structure decreases as a result of soil flexibility, the lateral natural period lengthens. The building frames situated on the Raft foundation may experience a significant change in seismic response due to this extension of the lateral natural period (T). Therefore, it is imperative to consider the soil's flexibility, also known as soil structure interaction, when doing analysis on the foundation's supporting layer.
 This paper examines how asymmetric building frames with raft footings behave dynamically when subjected to seismic forces that involve soil-structure interaction. The analysis is performed with SAP 2000*V21 FEM software. The structure is idealized as a three-dimensional space frame, with slabs modeled as a thin shell with four noded plate elements and six degrees of freedom at each node, and beams and columns modeled as two noded line elements. The soil is represented as equivalent springs with one (Winkler) and six (Modified Winkler) degrees of freedom; the stiffness of these springs varies depending on the type of soil and is determined by its dynamic shear modulus and poissons ratio. The Modified Winkler and Winkler raft foundations are modeled as thin shells with four noded plate elements, each with six degrees of freedom, and are criticized so that the element aspect ratios are equal to one.
 
 To assess the impact of soil structure interaction on building frames, the response is compared for a range of building frames with and without consideration of soil flexibility in terms of fundamental Natural Period, Seismic Base Shear, and Max. Lateral Displacement. The parametric study for Zone V takes into account the influence of various parameters, including the number of bays, stories, span lengths, and soil types (i.e., soft, medium, and stiff).
 
 It is discovered that the fundamental lateral natural period and seismic base shear of the system are significantly altered by the influence of soil flexibility on building frames. As soil stiffness decreases, the lateral natural period and seismic base shear increase as a result of soil flexibility. Additionally, it has been noted that as the number of bays increases, so do the building's base shear and lateral period. As the number of bays and stories increases, so does the maximum lateral displacement. 

GLARE deformation in low-restraint state: Tensile and bending behavior

Fiber metal laminates (FMLs) possess a better weight reduction effect than traditional metal materials due to the coupling properties of heterogeneous materials, showing promise in the areas of aviation and aerospace. At present, the research on FMLs mainly focuses on the deformation properties after curing while the mechanical properties in the low-restraint state, i.e. the laminates are temporarily not cured and are formed under lower constraint stresses, are not studied in detail. Herein, the low-restraint GLARE is taken as a research object and its deformation characteristics and failure mode are studied using uniaxial tensile, bending experiments and numerical simulation in this paper. Moreover, the influence of key parameters, such as temperature, laminate structure and span length, is investigated, as well as the tensile and bending deformation behavior of GLARE in a low-restraint state is obtained. In addition, based on experimental observations, it is found that the low-restraint GLARE produces the phenomenon of interlayer slip, and the interlaminar residual stress is much smaller than the cured laminate, whereas the deformation limit and performance are improved. This paper provides theoretical bases for the in-depth analysis of deformation properties and forming laws of low-restraint GLARE, guiding further applications of laminates.

Experimental investigation on UHPC-NSC composite beams

A hybrid beam composed of ultra-high performance concrete (UHPC) and normal strength concrete (NSC), is experimentally evaluated. The layout optimizes cost and performance by placing the UHPC full-depth section at mid-span of the hybrid beam. The length of the UHPC section compared to the span length (Lu/L) as well as the angle between the UHPC and NSC interface is varied experimentally, and the performance evaluated against fully NSC and fully UHPC control beams. The fully UHPC beam (BU) had an ultimate load 63.5% higher compared to the NSC beam (B). All three hybrid UHPC-NSC beams B0.5, B0.6, and B0.5I, having Lu/L ≥ 0.5, achieved ultimate loads of 92.3%, 95.8% and 94.2% of the fully UHPC beam ultimate load respectively. The failure of the hybrid beam with the inclined joint (B0.5I) was more gradual when compared with the beam with the straight joint (B0.5) having the same volume of UHPC. The hot joint between UHPC and NSC in the hybrid beams showed no joint separation. The developed 3D FE model was able to predict the load-deflection behaviour as well as crack locations and crack localization. In hybrid UHPC-NSC beams, steel yielding can initiate near the UHPC-NSC joint location, where unlike within the UHPC portion, the steel rebars are required to carry the entire tensile force. An analytical method is proposed to provide conservative design loads considering the different failures expected from the hybrid UHPC-NSC beam.

Vertical stiffness limit of 400 km/h high-speed railway simple-supported bridge considering excitation randomness

Vertical stiffness of the bridge is of paramount importance in guaranteeing optimal driving performance for high-speed railway (HSR) trains. Initially, the Auto Regression and Moving Average model with eXogenous input (ARMAX) model is employed as the surrogate model for the train-bridge (TB) coupling system. Then, the framework for analyzing vertical bridge stiffness is proposed employing the surrogate model, and the relationship between the train response affected by excitation randomness and the vertical stiffness indicators of the bridge is established. Finally, the influence of various factors such as train speed, train type, car body mass, and bridge span on stiffness limit of 400 km/h HSR simple-supported bridge (SSB) is examined. The results indicate that the surrogate model offers a notable advantage in computational efficiency, while maintaining a satisfactory accuracy in predicting the train response. With higher train speeds, lighter car body masses, and longer spans, the demand for stricter bridge stiffness limits becomes more pronounced. Based on the driving performance of the train types analyzed, the recommended stiffness limit is proposed for the prestressed concrete simply supported beam (SSB) bridges used in HSR, with a span length of less than 40 m and operating at a speed of 400 km/h.

Flexural creep response of honeycomb sandwich pultruded GFRP composite cross-arm: Obtaining full-scale viscoelastic moduli and creep coefficients

The application of pultruded glass fibre-reinforced polymer composites (PGFRPC) as a replacement material for conventional wooden cross-arm in high transmission towers is relatively new. Although there are several studies on enhancement of the cross-arm structure, there is still a lack of study on the elastic properties of a full-scale PGFRPC cross-arm enhanced with honeycomb sandwich structure. To full-fill the gap, this paper describes an experimental methodology used to obtain the elastic properties of the cross-arm using a three-point bending (3-PB) flexural test by following ASTM D790 standard for deflection behaviour and flexural creep response. The investigation involved several cross-arm members subjected to loading across different span lengths by propose two methods in order to measure the effective cross-arm member section flexural modulus (Ec) and shear modulus (Gc). The creep behaviour of the panels was successfully modeled using Findley's power law, confirming the ability of this empirical approach to simulate the viscoelastic response of the cross-arm. Next predictions were made for up to 50 years of service and the results shows the elastic modulus reduction for the enhanced cross-arm with the honeycomb sandwich structure was approximately reduce to 70 % compare with existing cross-arm which reduce almost 75 % at 50 years of application. The enhanced cross-arm exhibited lower deflection and better creep resistance and increased the bending strength of the cross-arm as well as extended its potential lifespan. Predictions indicated that the enhanced cross-arm maintained better mechanical properties over time compared to the existing one.

A New Analytical Method for Link Slab Analysis

Link slabs have been widely used to reduce the number of expansion joints. However, traditional reinforced concrete link slabs are prone to cracking issues, making it crucial to accurately calculate their internal forces. Currently, the most advanced link slab analysis methods treat the link slab and adjacent span as a rotational spring to simulate their restriction on the girder end rotation. However, this method does not comprehensively consider the link slab's influence, leading to conservative results. To address this issue, this study further considers the influence of girder end deformations on adjacent span, resulting in more accurate calculations of the link slab's internal forces. Additionally, the concept of the girder end rotation reduction coefficient is put forward for the first time, which provides a clearer and more quantified understanding of the link slab's influence. The proposed method is verified by a model test and a site test, which shows a significant improvement in accuracy compared to existing analytical methods. On this basis, a parametric study is conducted to investigate the influence of various parameters on the girder end rotation reduction coefficient, which indicates that span length, girder spacing, and support configuration have the greatest influence.

Fatigue Crack Propagation in 5754 Aluminum Alloy under Four-Point Bending

The aluminum 5754 alloy is one of the widely used engineering materials in shipping, rivet making, tread plates and automotive industries. These engineering structures envisage variable loading conditions during their service. In addition to it, it is also experiencing seismic vibrations. Hence, the engineering components made from such aluminum alloy are susceptible to fatigue fracture. In the current study, the prediction of fatigue crack growth (FCG) in 5754 aluminum alloy was made using the exponential function. The beam specimen comes up with a cross-section of 25X25 mm2, a span length of 300 mm with a mechanical notch length of 2.70 mm at the centre was subjected to four-point bending (FPB) employing hydraulic INSTRON 8800 tensile testing apparatus. The periodic loading condition deformed the material up to large plastic deformation. The applied load was further down the elasticity of the material. The experimental data provided the relation between crack length (a) to the number of cycles (N) to failure. The response surface methodology (RSM) and modified exponential equation were used to predict the FCG. In RSM, when “stress intensity factor (K)” and “number of the cycle (N)" were considered independent variables, the response (a) was optimum (maximum) as compared to when “stress intensity factor range (del K)” and “fatigue crack growth rate (da/dN)” were considered independent variables. Hence, for designing the aluminum 5754 alloys as engineering structures, it was the number of cycles which provides a safe design as compared to da/dN. The modified exponential equation using an exponential function predicted the FCG for aluminum 5754 alloy in the form of a beam specimen. The anticipated results agreed with experimental data as the prediction ratio was 1.20 and the % deviation was 3.7.

Analysis and Design of Transmission Tower using Staad-Pro

A transmission tower, also known as an electrical power tower or utility pole, is a tall structure used to support overhead power lines for the transmission of electrical energy. Transmission towers play a critical role in the reliable and efficient transmission of electricity from power generation plants to distribution networks and ultimately to consumers. This abstract provides an overview of transmission towers, including their purpose, types, components, and key considerations in their design and construction. Transmission towers are designed to withstand various environmental and loading conditions, such as wind, ice, and seismic forces while maintaining the integrity and stability of the overhead power lines. Different types of transmission towers, such as lattice towers, tubular towers, and pole towers, are used based on factors such as voltage level, span length, and terrain conditions. Analysis of this transmission tower is administered using STAAD PRO The present work describes the analysis and design of a transmission line tower of 31 meters in height and 220KV double circuit viz. various parameters. The components of a transmission tower typically include tower legs, cross-arms, insulators, and hardware for attaching conductors and ground wires

Estimation of Stature among Healthcare Workers using Arm Span, Biacromial Breadth, and Forearm Length Dimensions: A Cross-sectional Study

Introduction: Stature is one of the most commonly used anthropometric dimensions for identification purposes in forensic investigations and for assessing the development and growth of individuals. It is well-known that various anatomical anthropometric parameters can accurately estimate stature. Aim: To estimate stature among healthcare workers in Himachal Pradesh using linear regression equations based on percutaneous anthropometric parameters of the upper limbs and trunk. Materials and Methods: This cross-sectional study was conducted on healthcare workers at Dr. Rajendra Prasad Government Medical College, Kangra, Tanda, Himachal Pradesh for a one year (September 2021-August 2022) duration. The study included 360 healthy healthcare workers from the Himachal Pradesh population, 180 females and 180 males, aged 21 years and above. Stature, arm span, Biacromial Breadth (BAB), and forearm length dimensions were measured for each subject. Statistical analysis was done using Microsoft Excel and Epi-Info version 7.1 software. The Pearson Correlation Coefficient was used to determine the correlation between stature and different anatomical anthropometric parameters. Linear regression equations were developed to estimate stature, with significance set at p-value ≤0.001. Results: The mean age of the study population was 41.33±28.91 years. The descriptive anthropometric parameters measured in the study were as follows: stature 162.4±6.85 and 149.4±7.15, arm span 165.67±7.5 and 150.31±8.33, right forearm length 26.68±1.33 and 24.36±1.59, left forearm length 26.47±1.30 and 24.30±1.55, BAB 34.11±2.16 and 31.74±2.32, respectively for males and females. Conclusion: The regression equations derived from this study can be valuable for estimating stature in situations where accurate stature measurements are not feasible.

A comparative analysis of mechanical and optical behavioral patterns of translucent zirconia ceramics.

This research aimed to assess and compare the translucency and mechanical properties of partially stabilized zirconia in contrast to lithium disilicate, particularly within the context of translucent zirconia. The experimental design entails examining fifty samples, with ten drawn from each of the five distinct categories of ceramic materials, as part of this in vitro study. Translucency is measured using the Konica Minolta CM-3600D spectrophotometer, assessing Delta E through Lab values against white and black backgrounds. Flexural strength is analyzed via a 3-point bend test on a universal testing machine, with a controlled crosshead speed set at 1 mm/min. The study included the five categories of ceramic materials, each consisting of ten samples: High-strength zirconia (Katana HT), translucent zirconia (e.max Zircad MT and Cercon ht ML), and lithium disilicate (Press MT and LT). The Konica Minolta CM-3600D spectrophotometer is utilized to measure the translucency parameter. This involves determining the color difference (Delta E) by comparing the L*a*b values against both white and black backgrounds. The flexural strength (FS) of zirconia and lithium disilicate materials was analyzed through a 3-point bend test, aiming to compare their respective strengths. The testing procedure was carried out on a universal testing machine with a controlled crosshead speed set at 1 mm/min. The FS was calculated using the formula σ = FL/πR3 for circular disks, where σ represents the FS, F is the fracture load, L is the span length in millimeters, and R is the radius of the disk. The Student's t-test was employed for statistical analysis. The mean translucency parameter for e.max Press MT (6.33 ± 1.05) was significantly greater than all the specimens investigated. The Cercon ht ML exhibited a slightly higher translucency (2.18 ± 0.52) compared to e.max Zircad MT (1.49 ± 0.69), with a statistically significant difference (P = 0.022). Conversely, the FS of e.max Zircad MT (26.97 ± 2.06) was significantly greater (P < 0.001) than that of Cercon ht ML (23.25 ± 2.36). Notably, the Katana HT material demonstrated the highest load strength (32.92 ± 3.10), a statistically significant difference compared to its counterparts (P < 0.001). Among the materials tested, lithium disilicate ceramics exhibited the highest translucency, with its MT variant demonstrating the lowest strength. Katana HT displayed significantly greater biaxial FS compared to translucent zirconia, surpassing even lithium disilicate. Translucent zirconia proved to be notably more translucent than high-strength zirconia. Within the category of translucent zirconia, e.max Zircad MT exhibited substantially higher FS than Cercon.

Preliminary assessment of pre-1980 girder bridges in the framework of the Italian Guidelines

The Italian Guidelines issued by the Ministry of Infrastructure and Transportation are devoted to preventing damage on road bridges caused by the lack of maintenance and, in turn, avoiding safety or service problems affecting the infrastructure network. The multilevel approach foreseen by the Guidelines develops through the first three levels to attribute the Class of Attention, whose result indicates subsequent steps for more detailed assessment and monitoring actions to be undertaken. One of these actions is the preliminary verification which is performed by comparing stress values generated by the design load schemes used at the time of construction with the ones obtained by applying the current code. In this paper, preliminary verifications are performed on a series of simply supported girder deck models representative of the Italian state road bridges, obtained through a statistical study on a bridge inventory. Therefore, some performance indices related to the main bridge components are obtained with respect to shear and moment stresses for different bridge configurations in terms of the number of beams, span length, and carriageway width, which can be useful for rapid preliminary assessments of similar bridges.

Impact of unit prices on the optimal costs of reinforced concrete beams: A comparative study

Numerous studies have been conducted on optimizing reinforced concrete (RC) structures. However, the existing literature focused on reducing the overall costs of the structural members based on materials' local prices, neglecting that these prices could vary from region to region. Thus, this article investigates the impact of materials' unit prices on the optimal costs of RC beams, considering the prices of three countries: Egypt, the UK, and Brazil. The evolutionary algorithm provided by MS Excel Solver was employed to obtain the optimum designs based on three target functions: total cost, steel weight, and concrete weight. Unlike earlier studies, we provided a sufficient number of discrete design variables that significantly influence the total cost and weights of concrete and steel; these variables include the concrete class, cross-sectional dimensions, and details of reinforcing bars at all the critical sections of the beams. Two benchmark examples were presented to illustrate the robustness of the proposed optimization model in dealing with different span lengths and continuity conditions. The results showed that the optimal designs could significantly vary based on the materials’ unit prices. In Egypt, minimizing the steel weight could save up to 50% of the total cost, compared to reducing the beam concrete dimensions. The optimal steel-to-concrete and span-to-depth ratios were as low as 0.7% and 9, respectively. On the other hand, in the UK and Brazil, cost-effective designs could be achieved by minimizing the concrete dimensions, with higher reinforcement ratio (up to 1.3%) and span-to-depth ratio (up to 11.5). The study outcomes could assist designers in the building sector estimate economical concrete quantities based on the materials’ unit prices during the conceptual stage, enabling more informed decisions.

Application of Digital Image Correlation to Field Monitoring of Masonry Arch Bridges

Many masonry bridges constructed in Europe during the Industrial Revolution are still in service. For over a century, continuous operation and weathering effects have contributed to material degradation in the main bridge components. To ensure that old masonry bridges remain safe even under increasing traffic loading, it is crucial to identify potential deterioration in bridge performance before the onset of critical irreversible damage. This task can be accomplished via periodic monitoring of the bridge response under traffic loading. Digital Image Correlation (DIC) is an effective non-contact method to measure displacements and strains. Most DIC applications have been in laboratory settings, and DIC techniques have yet to be extensively applied in the field. This paper showcases the potential of DIC monitoring for serviceability assessment of masonry bridges. Some results of an extensive monitoring program on railway viaducts in the UK are presented. Structures with different geometrical characteristics, including pier heights, span lengths, and span-to-rise ratios, have been investigated. The results obtained using specific targets attached to the monitored structures or using the actual masonry texture as natural targets have been compared; consideration is also given to the influence of camera characteristics and settings. A significant impact of the camera depth of field has been established, especially when measuring deflections at different locations on the intrados of the arch barrel.

Pengaruh Kompleksitas Operasi, Solvabilitas dan Profitabilitas Terhadap Audit Report Lag Pada Perusahaan Manufaktur Yang Terdaftar di Bursa Efek Indonesia Tahun 2019-2020

The problem in this research is the Audit Report Lag, namely the delay in submitting the company's financial statements on the IDX beyond the specified time limit , namely the end of the fourth month , will be subject to sanctions in the form of payment of fines . The purpose of this study was to determine and analyze the effect of operating complexity, solvency, and profitability on audit report lag in manufacturing companies listed on the Indonesia Stock Exchange in 2019-2020. The population in this study are all manufacturing companies on the IDX in 2019-2020. The data collection technique used is purposive sampling method, with a total sample of 49 companies. The period contained in this study is 2 years, namely 2019-2020 so that the research data becomes 98. The research data analysis method uses logistic regression analysis with SPSS test equipment. The results showed that operating complexity had no significant effect on Audit Report Lag, Solvency had no significant effect on Audit Report Lag. Meanwhile, Profitability had a significant effect on Audit Report Lag. Simultaneously Operational Complexity, Solvency, and Profitability have no effect on Audit Report Lag. These results indicate that there are still many variables outside the research variables that can explain Audit Report Lag. The conclusion of this study is that the complexity of operations and solvency do not affect the length of time span for submitting financial statements, but companies must pay attention to regulations regarding the deadline for publication of financial statements.&#x0D;

The prevalence of Constituent Year effect in Youth Olympic Games: implications for talent identification and development in basketball

Purpose: The Relative Age Effect (RAE) and Constituent Year Effect (CYE) is increasingly recognized as a significant concern in youth sports, especially in basketball where physical traits such as height, arm span, and leg length are emphasized. This focus often eclipses the critical role of age-related variations in talent scouting processes. This study aims to explore the presence and impact of CYE in basketball, with a specific focus on the Youth Olympic Games (YOG). Methods: Utilizing statistical analysis, primarily the Chi-square test and Cramer's V, this research examines the occurrence of CYE among basketball players at the YOG. Results: The findings decisively confirm the existence of CYE in youth basketball (P= .000, χ2= 51.593, df= 2, Cramer's V= .403). Results of male (χ2 = 29.342, Cramer's V: .431) and female χ2 =23.43, Cramer's V: .383) also subsample suggest a significant skew in player selection based on birth year, with a large effect size in both cases. A notable discovery is the disproportionate number of athletes born in 2000, who are 19 times more common than those born in 2002, indicating a significant age-related skew in player selection. This indicates a strong association between birth year and player selection in the context of the YOG for both genders. Conclusions: CYE's prevalence in youth basketball could detrimentally impact athletes' development and teams' overall performance. The research emphasizes the need for a more equitable and balanced approach in athlete selection. The paper proposes practical steps to reduce CYE in basketball, such as narrowing age categories or establishing smaller, more precise age groups to ensure fairer competition and more accurate talent identification.

EXPERIMENTAL INVESTIGATION ON SELF REPLACEMENT OF SAND BY SHEET GLASS POWDER IN CONCRETE

For the hardened concrete, 150 mm × 150 mm × 150 mm cubic specimens and cylindrical specimens with a diameter of 100 mm and a height of 200 mm were tested to identify the compressive strength and splitting tensile strength of the concrete produced with waste glass. Next, a three-point bending test was carried out on samples with dimensions of 100 × 100 × 400 mm, and a span length of 300 mm to obtain the flexure behavior of different mixtures. According to the results obtained, a 20% substitution of WGP as cement can be considered the optimum dose. On the other hand, for concrete produced with combined WGP and crashed glass particles, mechanical properties increased up to a certain limit and then decreased owing to poor workability. Thus, 10% can be considered the optimum replacement level, as combined waste glass shows considerably higher strength and better workability properties. Furthermore, scanning electron microscope (SEM) analysis was performed to investigate the microstructure of the composition.