Shear Force Capacity Research Articles

Shear performance of FRP panel-reinforced rc columns attached using corner angles and bolts without epoxy resin

As the frequency of earthquakes has risen globally, the importance of seismic design in building construction has intensified. Fiber-reinforced polymers (FRP) are increasingly utilized as seismic reinforcement materials for reinforced concrete (RC) columns because of their lighter weight and superior strength compared to concrete and steel. However, the epoxy resin commonly used for FRP reinforcement is susceptible to fire, as it exhibits a glass transition temperature below 100 °C, and its performance can vary depending on the skill of the applicator. A method was therefore proposed to involve the non-adhesive application of FRP panels using corner angles and angle connections, eliminating the need for epoxy resin. Experimental and analytical studies were conducted to assess the shear performance of FRP-reinforced RC columns without adhesive attachment. The findings revealed that the maximum shear force capacity increased by more than 1.5 times compared to traditional RC columns. By securing the corner angle and FRP panel with angle connection materials, the attachment effect can be maximized to the extent of the corner angle area, suggesting its potential for enhancing shear performance.

Experimental behaviour, FE modelling and design of large-scale reinforced concrete deep beams shear-strengthened with embedded fibre reinforced polymer bars

Reinforced concrete (RC) deep beams are widely used in buildings and bridges. However, research on shear strengthening of RC deep beams with embedded fibre reinforced polymer (FRP) bars is limited. This paper presents the first comprehensive study on the experimental behaviour, nonlinear finite element (NLFE) modelling and design of large-scale RC deep beams strengthened in shear with embedded carbon or glass FRP (CFRP or GFRP) bars. An experimental investigation comprising three large-scale RC deep beams was conducted. Subsequently, a three-dimensional NLFE model was developed and validated against the experimental results. The validated NLFE model was used to perform a parametric study, examining the influence of FRP bar type and steel-to-FRP shear reinforcement ratio on shear strength enhancement. The results of the parametric study were utilized to calibrate and validate a novel design model. The results showed that embedded FRP bars can enhance the shear force capacity of large-scale RC deep beams by up to 40 %. The effect of FRP bar type on the shear strength enhancement was insignificant. However, there was 13 % reduction in shear force gain due to the increase in steel-to-FRP shear reinforcement ratio from 0.77 to 10.0. The novel design model reproduced the NLFE results with a mean ratio of 0.921 and a standard deviation of 0.018. Finally, the ability of the design model to capture the effect of the investigated parameters was demonstrated.

Insight into the evolution of textural properties and juiciness of ready-to-eat chicken breasts upon different thermal sterilization: From the perspective of protein degradation.

Texture deterioration of meat products upon high-temperature sterilization is a pressing issue in the meat industry. This study evaluated the effect of different thermal sterilization temperatures on the textural and juiciness of ready-to-eat (RTE) chicken breast. In this study, by dynamically monitoring the texture and juiciness of chicken meat products during the process of thermal sterilization, it has been observed that excessively high sterilization temperatures (above 100°C) significantly diminish the shear force, springiness and water-holding capacity of the products. Furthermore, from the perspective of myofibrillar protein degradation, molecular mechanisms have been elucidated, unveiling that the thermal sterilization treatment at 121°C/10 min triggers the degradation of myosin heavy chains and F-actin, disrupting the lattice arrangement of myofilaments, compromising the integrity of sarcomeres, and resulting in an increase of approximately 40.66% in the myofibrillar fragmentation index, thus diminishing the quality characteristics of the products. This study unravels the underlying mechanisms governing the dynamic changes in quality of chicken meat products during the process of thermal sterilization, thereby providing theoretical guidance for the development of high-quality chicken products.

Experimental investigation of the shear force capacity of prismatic cross laminated timber beams

Experimental tests of Cross Laminated Timber (CLT) under in-plane beam loading conditions are presented. The influence of the element layup, the individual lamination width, and the beam overhang at the supports on the shear force capacity was investigated. All the CLT beams had the same gross cross section, and a 4-point-bending test setup was used. The experimentally determined load-bearing capacities are compared with the load-bearing capacities resulting from analytical methods proposed for structural design, focusing on shear failure in the crossing areas of flatwise bonded laminations (shear failure mode III). The test results indicate no or very small influence of the element layup and the lamination width on the shear force capacity. These results partly contradict the predictions of the proposed design methods. Of the three studied beam geometry parameters, the beam overhang at the support had the greatest influence on the load-bearing capacity.

Perbandingan Kapasitas Kolom Beton Bertulang Berdasarkan Variasi Bentuk Sengkang dengan Analisis Finite Element Method

Columns are one of the structural elements that greatly influence the behaviour of the structure. Columns are capable of holding axial compression loads and transmitting them to the structural elements below. Column capacity can be increased by the confinement of lateral reinforcement/stirrup. The stirrups function to maintain the compressive strength capacity of the concrete column before and after spalling. Advances in software technology have had a very significant impact on the development of structural element analysis methods, including software based on the Finite Element Method (FEM), Abaqus/CAE Student Edition. It can also simplify several laboratory research of Civil Engineering into a simulation. However, in simulation practice, parameters in the form of material data are needed as input. To get the same behaviour between the test object and the simulation, convergent parameters are needed. The parameters to be analyzed are CDP (Concrete Damage Plasticity) plastic parameters. While the simulation for loading, shape of the test object, and placement refers to the results of previous studies. The reinforced concrete column test model used consists of 5 (five) different variations of stirrups. The results of the simulation show that reinforced concrete columns with stirrups provide support in the form of shear force capacity that can maintain the value of the axial compressive strength capacity. From the five existing test models, it was obtained that the increase in the value of the axial compressive strength capacity of the column due to the variation of stirrups for column B, column C, column D, and column E to column A (without stirrups) were 115%, 120%, 121%, and 119% consecutively. The output values from the analysis include the diagrams of axial force and displacement, column interaction diagrams, and material stress-strain diagrams

Shear Behaviour of RC Beams: A Numerical Study

A two-dimensional (2D) nonlinear finite element (FE) model created for reinforced concrete (RC) beams is presented in this paper. The FE model was verified in order to perform further parametric studies on RC beams with and without existing steel shear links. The parameters were tension reinforcement ratio, concrete compression strength, and beam size. Moreover, the accuracy of “Turkish Standards 500: Requirements for design and construction of reinforced concrete structures (TS500)” in terms of predicting the total shear force capacity of RC beams was examined. The FE model properly captured the experimental load capacity, with a mean value of 1.04. The increase in overall shear force capacity caused by the increasing tension reinforcement ratio from 1.79 to 3.33% was 18.3% for RC beams with existing steel shear links, whereas it was 10.6% for RC beams without existing steel shear links. The total shear force capacities of RC beams with and without steel shear links increased once concrete compression was increased from 30 to 70 MPa. An increasing beam size resulted in a reduction in shear stress at failure of 33.8% and 32.7% for RC beams with and without shear links, respectively. TS500 design code gave conservative results in calculating the overall shear force capacity of RC beams.

Effects on meat quality of Yerba mate (Ilex paraguariensis) in the diet of chickens

The objective is to evaluate the effects of the inclusion of yerba mate in the diet on the yield and quality of chicken meat stored frozen for 120 days after slaughter. The birds were distributed in a completely randomized design, with four treatments, and eight replications with 25 birds each. The treatments consisted of providing a basal diet with 1, 2, 4, and 6 g kg-1 of ground dehydrated Yerba mate. At slaughter, temperature, pH, and carcass yield were measured. 120 days after meat freezing, measurements of pH, colorimetry, cooking weight loss (CWL), shear force, and water retention capacity were estimated. The parameters evaluated after slaughter showed regression effects on breast and drumstick temperature. Breast temperature showed a decreasing linear effect (R2=0.61). For the variable thigh temperature, there was a negative quadratic effect (R2=0.66). The quality characteristics of breast and drumstick evaluated 120 days after freezing showed an increasing linear effect of drumstick CWL (R2=0.38). Yerba mate can be included in up to 6 g kg-1 in chicken feed without changing pH, color, and meat tenderness after 120 days of freezing, maintaining carcass and cut yields.

Novel Use of Scanning Methods to Investigate the Performance of Screw Connections in Timber-Concrete Composite Structures

This paper investigates the shear force capacity, stiffness, and effective length of the connection screws in timber-concrete composite structures. Ten samples (six hardwood and four softwood) were fabricated with the connection screws installed at different angles through the interface. The shear force capacities and the global stiffness characteristics of the connections were determined directly from double shear tests. The local characteristics of the screw connections were investigated by scanning the final residual screw shapes at the end of the tests for softwood specimens. Using the 2D digital scans of the screws, the screw curvatures were determined. From the curvatures, the local distribution of moment along the screw embedded within the concrete at the conclusion of the test was estimated. The distance of the plastic hinge in the screw within the concrete from the interface between the concrete and timber (the effective length) was obtained from the maximum bending moment location calculated via this image scanning method. Empirical equations of effective screw length were developed from the test data and applied in a shear force capacity model for softwood. These new equations of effective length of inclined screws in connections predicted the shear force capacity of the connection better on the softwood specimens. In hardwood specimens, the screw failed in snapping. An equation of shear force capacity was developed based on the influence of the inclination angle of the screw with the reduction factors and can predict the shear capacity of the connection in hardwood specimens.

Experimental Investigation of Ultimate Shear Force Capacity of Glulam Reinforced with Glued-in Threaded Rods

Background: Glued-in threaded (GIT) rods have been considered an effective timber connection method having several advantages, such as high load-carrying capacity, great stiffness, and good fire resistance. This type of connection has widely been utilized in newly built modern timber structures and for reinforcing the existing ones. Objective: The purpose of this experimental research is to investigate how the ultimate shear force capacity (USFC) of glulam is affected if it is reinforced with GIT rods and to study the interaction between the glulam and GIT rods. The results of this research can help researchers and engineers to select a suitable method of reinforcing the glulam with GIT rods at a superior inclination angle (IA) to the fiber direction in order to achieve higher USFCs. Methods and Experimental Tests: A total of forty glulam samples were tested for failure. The experimental tests consisted of five different series of samples with eight samples in each series. Sample series 1 were unreinforced glulam. Sample series 2 and 4 were glulam reinforced with the GIT rods at two different IAs of 45° and 90° to the fiber direction, respectively. Sample series 3 and 5 were glulam reinforced in the same way as sample series 2 and 4, but they were split in the middle. The samples were tested for failure using a standard testing machine. The machine was connected to a computer that recorded all the values obtained from the tests. Results: The results of the study were obtained as force-displacement graphs. The stiffness of the samples and interaction between the glulam and GIT rods were also calculated. The results achieved from the experimental tests of different series were compared and discussed. Conclusion: The experimental tests resulted in a 12.5% increase in the average USFC of sample series 2. However, the average USFC of sample series 4 was not enhanced significantly. The interaction between the glulam and GIT rods was obtained as 31.8% for the samples with reinforcing at the IA of 45° to the fiber direction and 3.8% for the samples with reinforcing at the IA of 90° to the fiber direction. Reinforcing the glulam with the GIT rods demonstrated the potential of enhancing its USFC. However, reinforcing the glulam with the GIT rods at the IA of 45° to the fiber direction was found to be superior to reinforcing the glulam with the GIT rods at the IA of 90° to the fiber direction.

Physics-based probabilistic capacity models and fragility estimates for light wood frame shear walls

Light wood frame buildings are common in the United States, and due to their prevalence, there has been significant damage to this type of building in previous earthquakes. For this building type, shear walls (typically sheathed with oriented strand board) are the main lateral force-resisting element. Probabilistic models and fragility estimates incorporating the prevailing uncertainties for shear walls are needed to make accurate predictions of the effects of future earthquakes on buildings of this type. This paper uses experimental data to develop probabilistic capacity models for the shear force and drift of light wood frame shear walls at the yield, peak, and ultimate performance levels. The proposed models are applicable to shear walls in low-rise buildings where the shear deformation is dominant. Moreover, the proposed models are applicable to walls that are similar to walls in the dataset. The probabilistic models are constructed starting from deterministic models. For the shear force, a new deterministic model is proposed. This model predicts the shear force capacity of the wall based on the capacity of individual nails. For drift, existing deterministic drift limits are used. The deterministic models are then improved by incorporating the effect of additional physical characteristics through explanatory basis functions that are shown to be significant in a probabilistic model selection procedure. Finally, fragility estimates are constructed for an example shear wall using the proposed capacity models and conditioning on the shear force and drift demands.

Shear Force Capacities of H-Type Furniture Joints Constructed of Various Heat-Treated Wood Species

The aim of this study was to investigate the effect of wood species, heat treatment, adhesive type and joint technique on shear force capacity of H-type furniture joints. For this purpose, an experimental design that consisted of 3 wood species, 2 treatment processes (untreated, heat-treated), 2 adhesive types (polyurethane (PUR), polyvinyl acetate (PVAc)) and 2 joint techniques (dowel, mortise-tenon (MT)) and 5 replications for each group were prepared, and accordingly, a total of 120 specimens were tested under static shear loads. Siberian pine (Pinus sibirica), Iroko (Chlorophora excelsa), and common ash (Fraxinus excelsior), which are commonly used in furniture constructions, were used as wood species. In general, iroko showed the highest shear force capacity between the wood species. The specimens constructed of heat-treated wood species showed lower shear force capacity by approximately 15 % in comparison to the same untreated specimens. MT joints showed better performance than dowel joints higher by approximately 21 %. PVAc adhesive gave higher values than PU adhesive by around 5 %. According to the results of four-way interactions, highest shear force capacities of H-type joints were obtained from “Common ash-PVAc-MT” combination in groups of untreated specimens and from “Iroko-PU-MT” combination in groups of heat-treated specimens.

A comparative study of the novel externally-attached precast SRC braced-frames for seismic retrofitting under near-field spectrum-compatible non-stationary stochastic earthquake

Seismic retrofitting is a hot issue in the field of earthquake engineering, and the externally-attached substructure approach is a well-known solution due to its no-disturbing construction and high-efficiency improvement. In this paper, a comparative study of a novel externally-attached precast steel-reinforced-concrete (SRC) braced-frames for seismic retrofitting is performed, and the near-field spectrum-compatible non-stationary stochastic earthquakes are generated as the excitation to reflect the input uncertainty. The construction and simulation approaches of the novel substructure are first introduced, and then the generation theories of near-field spectrum-compatible non-stationary stochastic earthquake are explained. The comparative study of five scenarios is conducted, via a 3-span-5-story existing reinforced concrete frame, and a series of performance indices are adopted for analysis, including the inter-story deformation, inter-story shear force, section-mechanical performance, and energy-consumption capacity. In general, the comparison study verifies the effectiveness of the novel externally-attached SRC braced-frames for retrofitting, and the external frame obviously reduces the axial force of the existing beams and columns, which indicates that the shear demand is transferred to the external substructures and the damage accumulation is well controlled after retrofitting. Although the inter-story performance and energy-dissipation capacity of the external substructures are not as direct as the bare brace scenarios, the external frames alleviate the potential premature damage of the existing joints and avoid the infills or facades of the existing building to place external braces, which provides a practical reference for the engineering application and future research.

Macroscale Superlubricity with Ultralow Wear and Ultrashort Running-In Period (∼1 s) through Phytic Acid-Based Complex Green Liquid Lubricants.

Liquid superlubricity has attracted much attention, due to its ability to significantly reduce friction on the macroscale. However, the severe wear caused by the long running-in period is still one of the bottlenecks restricting the practical application of liquid superlubricating materials. In this work, the obtained polyethylene glycol-phytic acid (PEG-PA) composite liquid lubricants showed outstanding superlubricating properties (μ ≈ 0.006) for Si3N4/glass friction pairs with an ultrashort running-in period (∼1 s) under high Hertzian contact pressure of ∼758 MPa. More importantly, even after up to 12 h (∼700 m of travel), only about 100 nm deep wear scars were found on the surface of the glass sheet (wear rate = 2.51× 10-9 mm3 N-1 m-1). From the molecular point of view, the water molecules anchored between the two friction pairs have extremely low shear force during the friction process, and the strong hydrogen bond interaction between PEG and PA greatly improves the bearing capacity of the lubricant. This work addresses the challenge of liquid superlubricant simultaneously exhibiting low shear force and high load-carrying capacity and makes it possible to obtain liquid superlubrication performance with an extremely short running-in time.

Effects of Dietary Supplementation of Chinese Yam Polysaccharide on Carcass Composition, Meat Quality, and Antioxidant Capacity in Broilers.

The study aimed to evaluate the influences of the dietary supplementation of Chinese yam polysaccharide (CYP) on the carcass performance, antioxidant capacity, and meat quality of broilers. Three hundred and sixty healthy 1-day-old broilers with similar body weight (39 ± 1 g, gender balanced) were randomly divided into four groups (control, CYP1, CYP2, and CYP3 groups). In the control group, broilers were fed a basal diet with CYP, and the CYP1, CYP2, and CYP3 groups were fed diets supplemented with 250, 500, and 1000 mg/kg CYP, respectively. There were three replicates in each group, 30 birds in each replicate, and the feeding trial lasted for 48 days. Statistical analysis was performed using SPSS 17.0 (SPSS Inc., Chicago, IL, USA) by one-way analysis of variance. The results showed that compared with the control group, dietary supplementation with 500 mg/kg CYP can improve live weight, half-eviscerated carcass percentage, eviscerated carcass percentage, and thigh muscle percentage. Moreover, dietary supplementation with 500 mg/kg CYP can improve the contents of total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD), glutathione peroxidase (GPX), and glutathione s-transferase (GST) in serum (p < 0.05). Meanwhile, the mRNA expression levels of nuclear factor-erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), quinone oxidoreductase (NQO1), superoxide dismutase 1 (SOD1), glutathione peroxidase 1 (GPX1), and catalase (CAT) in the liver; the mRNA expression levels of HO-1, NQO1, GPX1, and CAT in the breast muscle; and the mRNA expression levels of NQO1, SOD1, and CAT in the thigh muscle of broilers in the CYP2 group were significantly increased (p < 0.05). In addition, the yellowness and shear force of the thigh and breast muscles and the content of malondialdehyde (MDA) in the serum of broilers in the control group were higher than that in the CYP2 groups (p < 0.05). The results demonstrated that the CYP2 group had the best effect on improving meat quality. In conclusion, dietary supplementation with 500 mg/kg CYP can improve the meat quality of broilers by improving carcass quality, meat color, shear force, and antioxidant capacity.

A Numerical Investigation to Calculate Ultimate Limit State Capacity of Cable Bolts Subjected to Impact Loading

As rock bursts are unavoidable in deep mines and excavations with high in-situ stresses, ground support systems are implemented to manage and mitigate rock bursts. Cable bolts are commonly used as reinforcing elements in ground support systems, which are subject to dynamic loads in burst-prone excavations. To design an efficient cable bolt in burst-prone conditions, shear and energy absorption capacity must be considered. Numerical modelling is an advantageous method of repeatable testing and it is inexpensive and non-destructive. This study develops a statically and dynamically loaded numerical model of a double shear test in ABAQUS/Explicit. A total of 36 static and 576 dynamic tests are carried out, which examine the influence of bolt diameter, steel yield and ultimate strength, dynamic load velocity and dynamic load mass on the displacement, shear force and energy absorption capacity of cable bolts. As bolt diameter and steel yield strength increases, the maximum shear force resisted and bolt displacement increases. Similarly, as the mass and velocity of the dynamic load increases, the amount of energy absorbed by the cable bolt increases. The main novelty of the current research is to suggest a reliable computational tool to investigate the influence of the different key parameters in the cable bolts on the ultimate capacity. The suggested method is a significantly cost-effective technique compared with the experimental investigations.

Experimental study on the seismic behavior of RC columns with high axial compression ratios retrofitted by large rupture strain fiber-reinforced polymer

Fiber-reinforced polymer (FRP) composites being utilized to retrofit reinforced concrete (RC) columns has been well documented. However, the axial compression load of the FRP retrofitting RC columns was relatively limited. Aiming to analyze the applicability of FRP retrofitting RC columns with higher axial compression loads, this paper presents an experimental study on the seismic performance of RC columns retrofitted by the Polyethylene Terephthalate (PET) FRP composites. A total of twelve 1/3 scale RC columns were fabricated, including four control specimens and eight PET FRP retrofitting columns with two retrofit schemes. All the columns were tested under combined high axial compression load and cyclic lateral displacement excursions, and the maximum axial compression ratio reaches 1.1. The seismic performance of RC columns retrofitted by PET FRP was analyzed detailedly from the failure mode, shear force and deformation capacity, energy dissipation and ductility. The test results showed that PET FRP retrofitting changed the failure mode of RC columns from brittle to more ductile. The post-peak strength degradation of the columns was more rapid with the increase of axial compression ratio, but the strength degradation of the PET FRP retrofitting columns was more gradual. PET FRP retrofitting significantly improved the ductility and lateral deformation capacity of the columns even under the high axial compression ratio. PET FRP retrofitting can be applied for the RC columns with serous demand of deformation capacity due to the lighter change of shear-loading capacity and stiffness. Contrastively, the improvement of the seismic capacity of the RC columns retrofitted by the laterally wrapped scheme is higher than that of the striped wrapped scheme. Conclusions from this study provide useful references for the seismic retrofitting of RC structures.

Comparison of Various Types of Seismic Hazard Assessment and their Influence on Structural Vulnerability

This work sought at enhancing techniques for the assessment of seismic risk in order to understand displacement effects and impacts of different seismic hazard estimation techniques on structural vulnerability. The analysis is useful because the number of earthquakes around the world is on the rise, and there is a necessity to eliminate the potential threat. Weighted Average of Ground Motion intensities was used to determine hazard parameters, along with PSHA and DSHA. The information regarding seismicity was collected from the regional networks and catalogs with the help of geotechnical investigation for site characteristics. An assessment of structural resilience was accomplished with building inventories and retrofit projects data with the help of FEA for computational modeling. The degree of earthquake was recorded to be from 4. 5 to 7. 5 Mw, with PGA ranging from 0 to 0. 2 to 0. 3g. During preliminary screening, Sites were ranked into high PSA and low PSA divides as well as Low Seismic Hazard and Medium to High Seismic Hazard. These retrofitting measures such as base isolation and strengthening further improved performance of buildings, in that they reduced peak drift ratios by up to 50% and, base shear force capacity by 30% of average value. The Effectiveness Index of retrofitting work varied from 0. 732 to 0. 912, from which one can draw the conclusion concerning appreciable enhancements of earthquake resistance. The study thereby laid a foundation to prove that it is possible to reduce the seismic risk by using the advanced hazard analysis methods and based on these analyses, some systematic retrofit interventions are effective enough in achieving the objective of sustainable urban development. The conclusions derived in this paper present quantitative information relevant for understanding actions toward earthquake prevention in vulnerable territories.

Effect of Elastomeric Bearings in Bridge Piers

In this paper, the influence of elastomeric bearings is investigated in terms of seismic responses and presented under effects of severe ground motions. For this purpose, seismic performance of an isolated pier system is analytically studied by using time history analyses. The isolation system is assembled by elastomeric bearings composed of rubber layers and steel-shims. The bearings are located between pier-top ends and box-girder of the bridge deck. Seismic solutions are obtained for isolated system and non-isolated pier system known as rigid connection. Time-dependent response quantities are obtained in transverse direction for two strong quakes. Additionally, nonlinear static procedure is carried out to obtain lateral seismic capacity. Thus, the displacement and shear force capacity are determined for the considered pier systems. Seismic responses are comparatively presented in terms of superstructure and base response values. Thanks to the isolation system, the bearings have yielded lower peak displacements and base responses with seismic demand as well. On the other hand, higher seismic capacity has been obtained in case of isolation system and the results are presented by computed lateral capacity curves. The results show that the elastomeric bearing is an effective tool in lateral strength and modal behavior of the pier system as well.

Effects of different intermittent illumination patterns on production performance of slow growing type Yellow chickens

Abstract The objective of this study was to investigate the effects of intermittent illumination around noontime on the F line of slow growing line of Yellow chickens. The chickens were randomly divided into three groups of 70 roosters and 100 hens kept under three different illumination patterns. Group I was the control group (16 h of illumination at 10 lux). After day 21, in group II the light was additionally turned off during noon from 12:00–13:00 and in group III from 12:00–14:00 based on the lighting schedule of group I. The results showed that there was no significant difference in body weight (BW) between the three groups during the first 21 days ( p> 0.05). On day 42, BW of roosters and hens in group II was 35.2 g/21.7 g and 39.7 g/27.3 g higher than that of those in groups I and III ( p< 0.05), but there were no significant differences between group I and III ( p> 0.05). Oblique body length and shank length of group II were significantly higher than in groups I and III (p<0.05). After day 43, feed conversion ratio of group II was significantly higher than in groups I and III (p < 0.05). Comb perimeter, area and vertical area of group I were significantly higher than in groups II and III, and in group II these parameters were significantly higher than in group III (p<0.05). Slaughtering weight and breast muscle percentage of group II were significantly higher than in groups I and III, leg muscle percentage was significantly lower in group III ( p< 0.05) compared with the other groups. On day 84, there were no significant differences in blood indices (IGF-1, growth hormone, testosterone) or meat quality indices (flesh colour, shear force, PH, and water-holding capacity) between the three groups ( p> 0.05), but some indicators in group II showed an increasing trend. Based on these results, the intermittent light pattern of group II not only saved electrical energy and diet resources but also improved some indices of production performance.

EVALUATION OF THE DESIGN OF RETAINING WALLS ON THE ROAD SUKABUMI (BAROS) - SAGARANTEN KM BDG 115+200

&lt;p&gt;The Sukabumi (Baros) – Sagaranten Km Bdg 115+200 road section which is located in Sukabumi Regency is a road section for the province of West Java. Because the road is always damaged due to being eroded by water infiltration in the rice fields that seeps into the road body area at that location and the soil at that location tends to be unstable based on the results of lab tests having a shear angle value of 4.99ᵒ and having a specific gravity of 17.45, then it is carried out analysis of the existing damaged retaining wall and the design of a new gabion-type retaining wall at that location. The gabion retaining wall building will be designed with 3 designs, the first using a stone volume of 13 m3, the second using a stone volume of 8 m3 and the third using a stone volume of 6.5 m3. Based on the results of the calculation analysis using Rankine theory, it was found that the existing retaining wall was unable to withstand the shearing force which got a check value of 1.18 which should have a value of SF &amp;gt; 1.5, while the 3 gabion plan buildings got the appropriate SF value, namely against the overturning force, shear force and soil bearing capacity.&lt;/p&gt;