Full-scale Trials Research Articles

Preliminary development of a tactical athlete nutrition score

Tactical athletes are at high risk for numerous conditions that are susceptible to nutritional intake. However, nutrition risk assessments in tactical athletes are not routinely implemented. The purpose of this paper was to describe preliminary development of the Tactical Athlete Nutrition Score (TANS). A cross-sectional study was conducted in a convenience sample of career firefighters (N = 150, all males) in southern California. Participants completed a 3-Day Food Record and other health-related questionnaires, and anthropometric measurements. The TANS was developed through best available evidence, observations, and an expert judgment exercise. The TANS include five variables: total energy, protein, omega-3 fatty acids, total sugar, and fruit and vegetable consumption. Risk levels were quantified according to data from these categories and analyzed accordingly. The TANS appeared to effectively differentiate individuals based on nutrition risk, with separation observed among the TANS risk levels – low risk (n = 7), moderate risk (n = 77), high risk (n = 66). One-way analysis of variance revealed significant difference among the risk categories for the five nutrition variables and TANS total (p < 0.001). The observed risk categories are plausible based on knowledge of this population. This study suggests the TANS is feasible to proceed to full-scale validation research trials. If validity is established, TANS will contribute to assessing nutrition risk level and improving nutrition interventions among tactical athletes.

Three Generations Micro-Allying Steel Processing: Thirty Years of Successive Work at CMRDI

The present article presents cumulative works, which were carried out in the field of micro-alloying steel processing at Central Metallurgical R&D Institute (CMRDI) and/or full scale trials in collaboration with the Egyptian steel industry.It was agreed upon defining three main generations of processing micro-alloying steel. The 1stgeneration starts officially on 1975 and continues up to 1995, where it deals with using Ti and V as micro-alloying elements for steel long products. On the year 1985, Central Metallurgical R&D Institute (CMRDI) succeeded to implement of HSLA V-micro-alloyed rebar steel grades at Delta steel mills instead of conventional rebar grades.The 2nd generation was starting on late 1995 and continued to 2005. It was dealing mainly with low carbon content steel (0.04-0.08 %) for flat products (plate and sheet). The most successfully used micro-alloying element was Nb. Beside its precipitate forming effect, Nb is working as substitution solid solution strengthener. Moreover, it raises the recrystallization temperature (Tr). Mainly, micro-alloyed flat steels were developed to fulfill the requirements of the American Petroleum Institute (API) specifications 5L- Product Specification Levels (PSL1) and (PSL2) for manufacturing oil and natural gas pipelines. Meanwhile, a newly born Compact Slab Processing (CSP)-hot strip direct rolling technology was created. On years 2002, the metal forming department in CMRDI succeeded to implement controlled rolling of hot strip Nb-steel sheet at the Compact Slab Process (CSP) Machine in Alexandria National Iron and Steel (ANSDK) Company. Controlled hot rolling schedules were used and followed by early and late cooling at the run out table (ROT). Both contracts were fruitfully succeeded to introduce the API X52 grade at ANSDK Company, followed by X60, and X70 steel grades at Ezz Flat Steel (EFS) Company. The essential mechanical properties of the processed API steel sheets were matched with the API 5L-PSL2 specifications.The 3rd generation was initially developed after 2005 and continued up to day. It deals with micro-alloying with special functional elements like Boron (B). Boron was favored as a micro-alloying element for bilateral effects. Boron carbide (B4C) precipitates are the hardest after diamond, which would be reflected on raising the mechanical properties of the steel. Moreover, Boron was favorably used because it delays the temper embrittlement phenomena. On year 2014, the National for Military Industrialization authority requested from CMRDI to collaborate with Military Factory 100 to develop a technology package for processing armor steel plates. Trials were started with a 3rd generation B-micro-alloyed steel alloy. Many other alloying elements were used beside Boron to develop extra high strength 6.0 mm thickness plates. Finish hot rolled plates were then subjected to a subsequent water quenching from 900 °C and followed by tempering at 250 °C for 20 min. Representation 50X50 cm2 steel plates were successfully passed after 3 bullets in front and 3 bullets rear shooting.

선수 스러스터를 이용한 실선스케일 조종시험에 관한 연구

This study aims to investigate the bow thruster performance of the research vessel “NARA” by full-scale maneuvering trials. The thruster test method refers to ITTC’s recommended procedures and guidelines. Turning tests with the bow thruster are performed at speed conditions of 0, 2, and 4 knots. The test results indicate that the Rate of Turn (ROT) increased when the ship is in a higher speed condition. Due to the position of the propeller and the housing of the bow thruster, there is difference in the efficiency of the bow thruster according to the turning direction. Zigzag tests with the bow thruster were conducted at speed conditions of 2 and 4 knots. At speeds above 4 knots, it seems difficult to change the course only with the bow thruster.

Towards a Realistic Estimation of the Powering Performance of a Ship with a Gate Rudder System

This paper presents an investigation on the scale effects associated with the powering performance of a Gate Rudder System (GRS) which was recently introduced as a novel energy-saving propulsion and maneuvring device. This new system was applied for the first time on a 2400 GT domestic container ship, and full-scale sea trials were conducted successfully in Japan, in 2017. The trials confirmed the superior powering and maneuvring performance of this novel system. However, a significant discrepancy was also noticed between the model test-based performance predictions and the full-scale measurements. The discrepancy was in the power-speed data and also in the maneuvring test data when these data were compared with the data of her sister container ship which was equipped with a conventional flap rudder. Twelve months after the delivery of the vessel with the gate rudder system, the voyage data revealed a surprisingly more significant difference in the powering performance based on the voyage data. The aim of this paper, therefore, is to take a further step towards an improved estimation of the powering performance of ships with a GRS with a specific emphasis on the scale effect issues associated with a GRS. More specifically, this study investigated the scale effects on the powering performance of a gate rudder system based on the analyses of the data from two tank tests and full-scale trials with the above-mentioned sister ships. The study focused on the corrections for the scale effects, which were believed to be associated with the drag and lift characteristics of the gate rudder blades due to the low Reynolds number experienced in model tests combined with the unique arrangement of this rudder and propulsion system. Based on the appropriate semi-empirical approaches that support model test and full-scale data, this study verified the scale effect phenomenon and presented the associated correction procedure. Also, this study presented an enhanced methodology for the powering performance prediction of a ship driven by a GRS implementing the proposed scale effect correction. The predicted powering performance of the subject container vessel with the GRS presented an excellent agreement with the full-scale trials data justifying the claimed scale effect and associated correction procedure, as well as the proposed enhanced methodology for the practical way of predicting the powering performance of a ship with the GRS.

A comparative review of the resistance of a 37,000 dwt Chemical Tanker based on experimental tests and calculations

The evaluation of ship resistance is of paramount importance having a decisive impact on the economic performances and efficiency depending on mission. If new IMO requirements through the Energy Efficiency Design Index (EEDI) are taken into account the necessity to have more and more accurate tools capable to consider the influences of different parameters became mandatory. The availability of towing tank facilities and the full scale trials are the practical means in order to be able to confirm the accuracy of theoretical formulations and to define the limits of CFD applications. Based on the results of the towing tank tests, a direct comparison with the results provided by classical methods and CFD computations can be systematically can be performed. On the other hand, the influences of the modifications operated on the fore part of the ship aretheoretically evaluated and compared with the towing tank results. Consequently, the paper is focused on the comparison of the results evaluated using different tools which have been carried out for a Chemical Tanker built by Constanta Shipyard Romania.
 

A MEG Study of Acute Arbaclofen (STX-209) Administration.

Several electrophysiological parameters, including the auditory evoked response component M50/M100 latencies and the phase synchrony of transient and steady-state gamma-band oscillations have been implicated as atypical (to various extents) in autism spectrum disorder (ASD). Furthermore, some hypotheses suggest that an underlying neurobiological mechanism for these observations might be atypical local circuit function indexed by atypical levels of inhibitory neurotransmitter, GABA. This study was a randomized, placebo-controlled, double-blind, escalating-dose, acute investigation conducted in 25 14–18 year-old adolescents with ASD. The study assessed the sensitivity of magnetoencephalography (MEG) and MEGAPRESS “GABA” magnetic resonance spectroscopy (MRS) to monitor dose-dependent acute effects, as well as seeking to define properties of the pre-drug “baseline” electrophysiological and GABA signatures that might predict responsiveness to the GABA-B agonist, arbaclofen (STX-209). Overall, GABA levels and gamma-band oscillatory activity showed no acute changes at either low (15 mg) or high (30 mg) dose. Evoked M50 response latency measures tended to shorten (normalize), but there was heterogeneity across the group in M50 latency response, with only a subset of participants (n = 6) showing significant M50 latency shortening, and only at the 15 mg dose. Findings thus suggest that MEG M50 latency measures show acute effects of arbaclofen administration in select individuals, perhaps reflecting effective target engagement. Whether these subjects have a greater trend towards clinical benefit remains to be established. Finally, findings also provide preliminary support for the use of objective electrophysiological measures upon which to base inclusion for optimal enrichment of populations to be included in full-scale clinical trials of arbaclofen.

Wadi gravel – a new concrete aggregate in Qatar: Part 1 – investigation, processing and trials

In hot desert regions, attention is turning to local sources of aggregate that were previously regarded as ‘too difficult' to exploit. This paper describes an investigation of such a deposit in Qatar. The material, known as Wadi gravel, is a gravelly sand of Tertiary age cemented by gypsum. A field survey found the gravel content to be in the range of 10 to 20%. As-dug samples had excessively high sulfate content, which could not be removed with conventional aggregate operations. However, intensive treatment in a local sand-processing plant using multi-stage crushing, screening and washing reduced the sulfate to acceptable levels. Petrographic analysis was carried out to identify rock types potentially susceptible to Alkali Silica Reaction (ASR). Trial concrete mixes using the processed Wadi gravel were found to produce satisfactory C40 and C60 concrete. Full-scale building trials were constructed to demonstrate the practicality of using the gravel and assess in-service performance. The smooth surface and rounded particles of Wadi gravel improved the concrete workability and strength, and durability-related properties were similar to concrete made with imported gabbro. Strata similar to Wadi gravel occur widely in hot desert regions and could be useful sources of coarse and fine aggregate for concrete.

The Analysis of Modified of Cakar Ayam (CAM) Designed with Concrete Plate Thickness Variation in Soft Soil

Modified of Cakar Ayam System (CAM) is a system that uses galvanized steel pipes as stiffener plate. This system had been implemented on the trial road of Pamanukan-Indramayu, Indonesia. Many advantages are obtained from the use of this system, for example reduction on deflection, durability, and application on road pavement. Full scale trials had been conducted in Indonesia, for the examples, the Waru-Surabaya Highway and Section IV Highway, Makassar. Despite this system is widely used but there are still many problems occur such as deflection and crack due to less plate thickness. This research will discuss about the deflection, moment and shear force of plate model on soft base ground using Finite Element Method (FEM). The system configurations for concrete plate applied in this research were 7.25 m in width and 14.0 m in length with thickness was varied by 0.15 m, 0.18 m and 0.22 m using 21 cakars. The loads represented semi-trailer truck loading with the weight of each axle propagated into 2 equal uniform loads. The position of test loading points were made in several variations to determine the largest deflection value. If the plate got thicker then, its stiffness value would increase and the deflection accorded smaller result. By using CAM System, cakar could function as a load restraint and plate grip. The stiffness of the plate would increase when the plate was applied with the CAM System and could reduce deflection by 2.74% to 39.77%. On the effect on the moment and shear force, it was found that the thicker the plate, the greater the moment and shear force value obtained. The difference in the value of the moment obtained from the comparison between the plate using the CAM System and the plate without the CAM System was 0.23% to 1.60%, while for shear force values, the difference was 7.56% to 11.19%.

A Systematic Review of Church-Based Health Interventions Among Latinos.

Latinos face healthcare access barriers and are highly religious. Church-based health interventions could help address these disparities. We conducted a systematic review of church-based health interventions among Latinos using multiple search terms and databases. The 21 articles reviewed represented 19 interventions. Only six were tested through full-scale randomized controlled trials and five had statistically significant improvements in health-related outcomes. Most (16) utilized groups classes, eight promoted screening or preventive services, and three provided these on-site. Few intervened at multiple levels (e.g., individual, group, and community) and only three utilized pastors' sermons to deliver health-related messages. Church-based health interventions among Latinos are nascent, with only a handful of full-scale trials. Various pilot studies demonstrating feasibility across diverse health conditions suggest model adaptability. Larger studies with objectively measured outcomes and interventions that address multiple levels and structural issues are needed to ensure improvements in Latinos' access and health.

Cooling characteristics of warm mix asphalt for multi-lift pavement repair and resurfacing

ABSTRACT Warm mix asphalt is gaining increasing acceptance in pavement construction due to their advantages in energy saving, reduced emissions and improved worker comfort. This paper highlights another benefit of warm mix asphalt (WMA) in allowing shorter road closure time window for pavement repair or resurfacing works as compared with the conventional hot mix asphalt (HMA) construction. This is of good practical value to busy roads where closure time windows as short as 4–5 h are common. A finite-element simulation model for predicting temperature cooling of WMA and HMA was developed to study the potential benefits of WMA in allowing shorter time windows for pavement repairs and resurfacing operations. Full-scale field trials were conducted to compare the temperature cooling characteristics of multi-lift construction of WMA and HMA, and provide the necessary data to calibrate and validate the simulation model developed. The validated simulation model was employed to analyse the cooling characteristics of HMA and WMA resurfacings under different environmental conditions and resurfaced layer thicknesses. These analyses provide useful information on the length of cooling time needed before the resurfaced layer is sufficiently stable to receive traffic. It was found that, compared with HMA, the use of WMA shortened the night-time cooling time needed by 5–35 min when the resurfacing thickness increased from 75 to 150 mm. The corresponding cooling time reductions for day-time paving were 19–79 min.

A religiously-tailored, multilevel intervention in African American churches to increase HIV testing: Rationale and design of the Taking It to the Pews cluster randomized trial

HIV continues to disproportionately impact African American (AA) communities. Due to delayed HIV diagnosis, AAs tend to enter HIV treatment at advanced stages. There is great need for increased access to regular HIV testing and linkage to care services for AAs. AA faith institutions are highly influential and have potential to increase the reach of HIV testing in AA communities. However, well-controlled full-scale trials have not been conducted in the AA church context. We describe the rationale and design of a 2-arm cluster randomized trial to test a religiously-tailored HIV testing intervention (Taking It to the Pews [TIPS]) against a standard information arm on HIV testing rates among AA church members and community members they serve. Using a community-engaged approach, TIPS intervention components are delivered by trained church leaders via existing multilevel church outlets using religiously-tailored HIV Tool Kit materials and activities (e.g., sermons, responsive readings, video/print testimonials, HIV educational games, text messages) to encourage testing. Church-based HIV testing events and linkage to care services are conducted by health agency partners. Control churches receive standard, non-tailored HIV information via multilevel church outlets. Secondarily, HIV risk/protective behaviors and process measures on feasibility, fidelity, and dose/exposure are assessed. This novel study is the first to fully test an HIV testing intervention in AA churches – a setting with great reach and influence in AA communities. It could provide a faith-community engagement model for delivering scalable, wide-reaching HIV prevention interventions by supporting AA faith leaders with religiously-appropriate HIV toolkits and health agency partners.

Inverse modeling approach for transformation of propeller shaft angular deformation and velocity to propeller torque load

In full-scale trials or model-scale tests, the propeller torque load is typically measured indirectly on the propeller shaft. Due to structural flexibility and mass of the propeller and propeller shaft, the measured propeller shaft torque response includes a time delay and amplitude difference compare to the propeller load. These differences are usually small during propeller operation, but may be significant during transient states (i. e. starting of the engine, rough sea, or operation in ice-covered waters). In this paper, an inverse model is used to calculate propeller load based on the propeller shaft response. The results indicate that the inverse model can be less complex than the complete propulsion machinery model and consider only the propeller and propeller shaft. Several modeling approaches are tested based on four proposed measuring setups and three forms of system discretization. Out of five inverse modeling approaches, two approaches showed the ability to transform measured propeller shaft angular deformation and velocity responses, colored with noise, into the corresponding rule-based propeller torque load with acceptable accuracy. Furthermore, the robustness of the inverse approaches to the random ice-propeller interaction, sampling frequency, measuring location along the propeller shaft and starting time (before and during ice-propeller interaction), is discussed.

Speed trial analysis method eliminating the need for external disturbance data

ABSTRACTShip speed performance is typically evaluated in the absence of external disturbances. Therefore, speed performance data obtained in full-scale trials are corrected to obtain speed performance with no external disturbances by eliminating disturbance effects due to wind, waves and current. This correction is called the speed trial analysis of ships. In this paper, a speed trial analysis method named as the power-based Taylor expansion method (PTEM) is presented, in which added resistance caused by an external disturbance and current velocity are not required. To verify this method, virtual speed trial data are generated theoretically for various current velocity conditions with constant wind, and the PTEM is applied to eliminate external disturbance effects from virtual speed trial data. Correction results are compared with known true results. The correction accuracy using the PTEM is sufficient even for varying current velocities with short periods. Furthermore, the PTEM is applied to the speed trial analysis of four full-scale tankers of the same hull form. The scatter of the correction results using the PTEM is smaller than that using other existing methods. The PTEM is useful as a speed trial analysis tool because it does not require external disturbance data.

Reduced Carbon Consumption and CO2 Emission at the Blast Furnace by Use of Briquettes Containing Torrefied Sawdust

Lowering the carbon consumption and fossil CO2 emissions is a priority in blast furnace (BF) ironmaking. Renewable biomass is one option that can play an important role in future low-carbon ironmaking particularly in the countries rich in biomass resources. In this study, full-scale trials to investigate the impact of briquettes containing torrefied sawdust on the BF efficiency and process stability have been conducted. Briquettes containing 1.8% of torrefied pelletized sawdust (TPS), 86.2% of steel mill residues, and 12% cement with sufficient mechanical strength have been produced on industrial scale. The bio-briquettes were charged at two different rates: 37% ( ~ 39 kg/tHM) and 55% ( ~ 64 kg/tHM) bio-briquettes to the SSAB BF No. 4 in Oxelösund. The gas utilization was higher during bio-briquette-charging periods without change in pressure drop up to 55% bio-briquettes, indicating sustained shaft permeability. BF dust generation or properties did not change significantly. Measurements of the top gas composition using mass spectrometry did not indicate release of hydrocarbon from TPS in connection to the charging of bio-briquettes. Evaluation of process data has been carried out using a heat and mass balance model. The evaluation of operational data in the model indicated lowering of thermal reserve zone temperature by 45 °C and reduction in carbon consumption by ~ 10 kg/tHM when charging 55% bio-briquettes compared to the reference case. The total CO2 emission was reduced by about 33–40 kg/tHM when using 55% bio-briquettes.

High-Speed Wave-Piercing Catamaran Global Loads Determined by FEA and Sea Trials

Wave-piercing catamaran hull forms are widely used for high-speed ferry applications due to the hull slenderness, suitable for achieving high speeds. The global loads acting on these craft are of great interest as there is limited knowledge on determining the magnitude of the loads, in particular when operating in random sea conditions. Longitudinal and transverse bending moments as well as pitch connecting moments and hull torsion loads act on the hull simultaneously. This paper investigates the estimation of these global loads from full-scale catamaran sea trials strain gauge data using finite element methods. Det Norske Veritas (DNV) load cases are applied to a finite element model in order to determine the conversion between local strain values observed during sea trials and prevailing global loads. Comparisons are thus made of global loads determined from strain data collected from sea trials with DNV global load cases. The results show that this method is relatively reliable for the prediction of hull global loads in the absence of slamming. Comparisons have been made for different heading angles. The quasi-static design loads are important during the ship design stage, as they are good proxies in wavelengths comparable to the hull length for rationally determined loads obtained from a first-principles dynamic analysis. The broad aims here are to demonstrate the use of strain sensor data obtained during sea trials for determination of global sea loads, to reconcile the loads thus determined with DNV load cases and thereby to improve the accuracy of the predicted loads used in design to increase the structural efficiency of vessel design.

Exploration of a systems and control approach to reduce propeller cavitation in a seaway

Dramatic increases in the underwater acoustic signature of ships have been observed during full scale trials in a seaway, compared to calm water conditions. The observed behaviour can be explained by the interaction of waves, wake field and ship propulsion system dynamics in combination with rudder action and ship motions. This paper explores whether a propulsion control system can increase the cavitation free time when sailing a straight course in a seaway. While in the past non-linear simulation tools have been used to analyse propeller cavitation in a seaway, the original contribution of this paper is that it considers the problem from a systems and control point of view. It is shown that the objective of significantly increasing the cavitation free time while simultaneously preventing thermal overloading of the diesel engine cannot simply be met by adjusting engine speed governor settings. It is however concluded that the developed plant and disturbance model are promising tools for advanced controller development and tuning aiming to reduce underwater acoustic signature.

FULL SCALE PERFORMANCE OF GATE RUDDER

This paper introduces full scale performance results obtained from voyage data taken from two 2400 dwt container ships, one equipped with the world’s first GATE RUDDER®. This is an innovative design, which is not seen as a conventional energy saving device and which has not been fully explored so far. The recent full-scale trials with this coastal container vessel have confirmed the superior performance of the GATE RUDDER® system which has shown 14% reduction in fuel consumption when compared with it’s sister vessel having a conventional rudder system. After 12 months from delivery, the voyage data from both vessels revealed that in some situations the gain could be much larger at abt. 27%. In this paper, the full scale operational performance differences from not only the model test but also the sea trial result are presented.

An extended ice failure model to improve the fidelity of icebreaking pattern in numerical simulation of ship performance in level ice

The modelling of the ice failure including icebreaking pattern and ice bearing capacity is an important issue in numerical simulations of ships going through level ice, in order to predict ship performance and ice loads. Previous studies model the shape of ice cusps assuming a simplified geometry, e.g. circular or triangular. According to the observations during full-scale ship trials, the geometry of the ice cusps is more elliptical rather than circular, with larger breaking length at the edges than that at the center. In this paper, a new ice failure model is developed which results in more realistic cusp shapes compared to existing approaches. The model is based on an analytically-derived differential equation, which is solved numerically via the Finite Difference Method (FDM). The predictions of ice cusps geometry are validated against full-scale measurement of ice cusps, obtained with an on-board stereo camera system. Satisfying agreement is shown. The ice failure model is incorporated into a numerical model for the prediction of ship performance in level ice. The predictions are compared with ship speed record obtained from a full-scale trial. It is shown that the model gives reasonable results for ship speed.

Impacts of seasonal variation and operating parameters on double-stage trommel performance

The high-level objective of this research was to quantify and assess impact of uncertainties of trommel screening with respect to feed-rate variation, clogging of screen apertures, and seasonal variation in waste characteristics, including particle size distribution (PSD) and composition using full-scale trials. A two-stage trommel screen which is operated at a municipal solid waste processing facility located in a cold region (Edmonton, Canada) was evaluated. The waste processed was co-mingled refuse with the recyclable material removed. The variation of size separation mass balance and recovery with respect to total and overs loading feed rate, season and operation time were monitored. The characteristics of the feedstock and separated waste streams were determined by sieve and compositional analyses. Separation and recovery results verified that the performance of the first stage where <5 cm of organic-rich waste was screened out, varied seasonally. Further, a strong linear correlation was obtained between recovery results and corresponding overs loading rate that varied between seasons. This correlation also varied within operation cycle during the winter trials due to clogging of screens. An equation is proposed to quantify clogging formation according to operation uptime and feed rate. Waste characterization results indicated the waste generated in the winter, spring, and summer had three distinct PSDs, especially the compostable fraction, contributing to the seasonality in trommel performance. In contrast, the PSD of the combustible fraction remained consistent in all seasons. This research successfully quantified the impact of uncertainties of full trommel operations in different seasons and during the operation cycle.

Performance of geosynthetic-reinforced flexible pavements in full-scale field trials

The paper presents the results of a series of full-scale trials carried out in Thailand examining the performance of geosynthetics as reinforcement for flexible pavements. The geosynthetics were embedded at different pavement depths and the structural response was monitored across four test sections by means of strain gauges, pressure sensors, deflection points and deflection plates. The results show that all reinforcement configurations helped reduce the vertical static stresses developed at the base of the pavement by up to 66% and by up to 72% for dynamic stresses. The performance enhancement expected to prolong the lifespan of the base layers. The reinforcement layers closer to the base experienced the highest lateral strains of up to 0.13%, providing evidence that geosynthetics can also effectively reduce lateral spreading. All reinforcement configurations helped enhance rut resistance with maximum traffic benefit ratio (TBR) of 13.70, effectiveness ratio (EF) of 12.70 and minimum rutting reduction ratio (RRR) of 0.74. The best configuration included a geotextile within the asphalt concrete layer and a geogrid under the base layer. Non-linear finite element analyses of the test sections predicted very well the strains and stresses in the pavement. The study provides a benchmark for future studies in this field and concludes that geosynthetics can help increase maintenance periods and extend the lifetime of flexible pavements.