Premature Distress Research Articles

Engineering properties-based parameters used for moisture damage evaluation of asphalt mixtures: a review

Moisture-induced damage has been known as a major premature distresses in asphalt pavement. Numerous review papers have been made to provide the progression in study on moisture damage of asphalt pavement. However, mechanical properties of asphalt mixtures used as a parameter for moisture susceptibility evaluation were not reviewed in detail. To make the review of moisture-induced damage in asphalt pavement more comprehensive, this paper reviews research studies on moisture damage of asphalt pavement in view of mechanical properties as a parameter during the past 50 years. These parameters include tensile strength ratio (TSR), cohesion ratio (CR), dynamic modulus ratio (DMR), resilient modulus ratio (RMR), and shear strength ratio (SSR). TSR and CR are only relevant at bottom of asphalt concrete (AC), while SSR can be used to describe moisture damage at different AC depths. DMR and RMR are concentrated on the impact of moisture damage via performance characteristics of asphalt mixtures.

Fracture Performance of Asphalt Concrete under Long-Term Vapor Exposure

Long-term vapor exposure generates persistent moisture gradients across asphalt pavement sections, driving moisture diffusion into asphalt concrete (AC). Moisture in AC weakens the materials and exacerbates the action of load, causing premature distress such as cracking in pavement. However, few investigations have focused on the effects of long-term vapor exposure on AC’s fracture performance. We approached this issue by simulating the fracture process of AC experiencing long-term vapor exposure under an indirect tensile load. The cohesive zone model (CZM) was introduced to depict the fracture process. We calibrated the CZM model by minimizing the difference between simulation and laboratory measurements. The results showed that long-term vapor exposure lowered the bonding strength in AC, accelerating the cracking initiation and propagation. The damage distribution showed that the interface between aggregates and mortar was more prone to damage since it bore more stress than the bulk of the asphalt mortar. This study reveals the fracture performance of AC under long-term vapor exposure, which helps develop measures to prevent premature cracking in the pavement and prolong the service life.

Stabilization of Soil in Road Construction Using Lime and Fly Ash

Abstract: Currently, inefficient soil properties are a crucial concern in engineering projects. In some cases, enhancing the characteristics of unsuitable soil is a necessary step to facilitate construction. Pavement structures built on weak soil sub grades exhibit premature distress, which leads to the early failure of the pavement. Silty soil often exhibits undesirable engineering behaviour, such as low bearing capacity, and high moisture susceptibility. Therefore, stabilizing these soils is a common practice to improve their strength.

Optimization of stone matrix asphalt mixture design based on fracture mechanics approach

Low-temperature cracking is one of the most common pavement distresses that occurred in a short period of service life and is known as premature distress. Stone matrix asphalt (SMA) with gap gradation, which has high strength and rutting performance, should also perform well against low-temperature cracking. So in this research, the criteria of SMA mixture design based on the National Cooperative Highway Research Program (NCHRP) 9–8 were optimized in a way so that SMA has the best performance against low-temperature cracking. Therefore, the optimization process was carried out using the response surface method (RSM) considering the combined effect of compaction energy (Ndesign) and binder content as mixture design factors. The fracture evaluation was done based on stress and energy. So critical stress intensity factor (KIC) and critical fracture energy (Gf) were used as fracture evaluation parameters. After conducting the tests and analyzing the results, it was found that 6.09 % binder with Ndesign = 78 leads to a design with a desirability of 0.869, which passed all the NCHRP 9–8 criteria of the mixture design in line with the maximum fracture performance.

Finite Element Modeling of Direct Transition from Concrete Pavement to Asphalt Pavement

The origin of premature distress in direct transitions from Portland cement concrete pavement (PCCP) to asphalt concrete pavement (ACP) constructed as part of TransMilenio pavement repairs has not been investigated and the related literature is limited, therefore, a three-dimensional finite element (FE) model was used to determine the mechanical responses of a direct ACP-PCCP transition under moving vehicular loading in order to identify failure mechanisms. In this sense, a PCCP model was validated with a falling-weight deflectometer (FWD) test, field measurements, and analytical solutions, then a concrete slab (CS) was replaced with flowable fill and asphalt concrete (AC) to create the direct ACP-PCCP transition. The direct transition model considered: 1) the viscoelastic nature of the AC; 2) non-uniform tire-pavement contact pressure; and 3) the bonding variation of the AC-concrete interface of the transition joint using different coefficients of friction (COF) and the Coulomb-type friction model. The results showed 1) relatively high near-surface shear strain of the AC, primarily at the joint and extending 122 mm from the joint; 2) relatively high compressive vertical strain on the subgrade top; and 3) high vertical differential displacement of the joint surface. It is concluded that the AC may prematurely experience near-surface cracking at the vicinity of the joint and rutting from the subgrade, however, increasing the AC-concrete interface bonding may be conservative for fatigue cracking and vertical differential displacement.

Statistical Validation of a New Tensile Creep Test for Asphalt Mastics

Abstract Currently, the increasing traffic level and climatic change are exacerbating the premature distress of pavement infrastructures. In order to assess this problem, the proposed research activity aims to statistically evaluate the parameters of a new mastic tensile creep test, which is based on a uniaxial tensile configuration. This allows the material deformation to be kept in the small-strain domain and the mechanical behavior to be considered as linear viscoelastic (LVE). Particularly, the main tasks of the study herein were the statistical analysis of the proper testing temperature and load. Moreover, the storage period of the samples was also analyzed, comparing four storage durations (1, 2, 4, and 12 h). The proposed analysis was performed using three fillers (one pure limestone and two limestone-based fillers) and two asphalt binders, neat and 3.5 % Styrene-butadiene-styrene (SBS) modified, respectively. The validation of the testing protocol also involved the analysis of the operator sensitivity using the one-way ANOVA statistical test. The results showed that the testing protocol is not operator-sensitive and allows the LVE behavior to be kept in the small-strain domain. The results also indicated that the m-value seems to interpret the accumulation of the permanent deformation for the mastic materials, which may be used as the property of materials, well.

Clinical analysis of 2860 cases of diabetes in pregnancy: a single-center retrospective study

BackgroundTo investigate the epidemiological, clinical characteristics and outcomes of diabetes in pregnancy (DIP).MethodsThis single-center, retrospective study included 16,974 pregnant women hospitalized during 2018–2019. Among them, 2860 DIP patients were grouped according to diabetes type, glycemic status, and insulin use. Multivariate logistic regression analysis was conducted.ResultsThe incidence of DIP [17.10%; pregestational diabetes mellitus (PGDM), 2.00% (type I, 0.08%; type 2, 1.92%); gestational diabetes mellitus (GDM), 14.85% (GDM A1, 13.58%; GDM A2, 1.27%)] increased annually. Premature birth, congenital anomalies, large for gestational age (LGA), neonatal asphyxia, neonatal intensive care unit transfer, hypertension, and puerperal infection were more common in DIP than in healthy pregnancies. The most common comorbidities/complications were hypertension, thyroid dysfunction, cervical incompetence, intrahepatic cholestasis, premature membrane rupture, oligo/polyhydramnios, and fetal distress. GDM incidence at ages ≥35 and ≥ 45 years was 1.91 and 3.26 times that at age < 35 years, respectively. If only women with high-risk factors were screened, 34.8% GDM cases would be missed. The proportion of insulin use was 14.06% (PGDM, 55%; GDM, 8.53%). Mean gestational age at peak insulin dose in DIP was 32.87 ± 5.46 weeks. Peak insulin doses in PGDM and GDM were 3.67 and 2 times the initial doses, respectively. The risks of LGA, premature birth, cesarean section, and neonatal hypoglycemia in PGDM were 1.845, 1.533, 1.797, and 1.368 times of those in GDM, respectively. The risks of premature birth and neonatal hypoglycemia in women with poor glycemic control were 1.504 and 1.558 times of those in women with good control, respectively.ConclusionsThe incidence of adverse outcomes in DIP is high.

Hydrophobic Effect of Soil Stabilization for a Sustainable Subgrade Soil Improvement.

The chemical process of using additives to stabilize soils is to improve soil that lacks strong engineering properties. In particular, the moisture susceptibility of subgrade soil through seasonal rains is still questionable. The presence of water in the construction is the cause of deterioration and premature distress of pavements and their supporting geotechnical structures. In this work, the chemical use of hydrophobic caltite (HC) in various amounts (ranging from 3%, 5%, to 7%) and 5% of cement to enhance laterite soils is investigated. The investigation includes the evaluation of soil properties, such as, unconfined compressive strength (UCS) by curing in air and under water, flexural strength (FS), and California Bearing Ratio (CBR) soaked and unsoaked. The addition of caltite with cement increases the strength characteristics with the UCS values of 2078–2853 kPa during the early curing stages (7th day), and 4688–4876 kPa after 90 days of curing. The added caltite in the cement soil samples shows a reduction index of strength loss underwater with the UCS values of 3196, 3334, and 3751 kPa for caltite cemented soil when compared with cement soil alone. FS results suggest that the inclusion of caltite in cement means that post-peak behavior can be enhanced, reducing the brittleness and increasing the ductility. The successful reaction with soil additives occurred in the curing period of 7 days. In terms of the microstructural analysis, results show that HC with cement reduces the porosity, voids, and cracking of laterite soils. Furthermore, new polymer globules, products from the reaction, appeared on the clay particle surfaces, thereby reducing the water absorption. The addition of hydrophobic-caltite to the soil–cement mixture results in increased strength and reduced water absorption in a soil–cement mix, thus achieving a given strength value.

Correlating strength and durability to time-temperature profiles of high-performance mass concrete

The temperature rise in mass concrete usually leads to premature distresses and early-age cracking. This paper correlates the time-temperature profiles to the mechanical properties and durability of high-performance mass concrete (HPMC). Five types of cement having different specific surface areas (SSA) and granulated blast furnace slag (GBFS) replacement rates are tested. Thirteen thermocouples were inserted at various locations inside a 1-m3 formwork to record the rate of concrete temperature rise, maximum temperature (Tmax), and time needed to attain Tmax. The mechanical properties were characterized by the compressive and flexural strengths, while the durability was evaluated using the drying shrinkage, water permeability, and chloride migration. Experimental results showed that concrete containing fine cement exhibited better strength and durability, yet increased tendency to thermal cracks and drying shrinkage. The partial cement replacement by GBFS reduced the concrete rate of temperature rise and Tmax, which led to reduced shrinkage. Analytical correlations and multivariable linear regression models were developed to predict the effect of SSA, GBFS replacement rate, and 28-day heat of cement hydration on the time-temperature characteristics and durability of HPMC.

Use of COVID-19 single-use face masks to improve the rutting resistance of asphalt pavement

Today, the world faces an enormous increase in plastic waste pollution caused by the emergence of the COVID-19 pandemic. Plastic pollution has been already one of the greatest threats to our planet before the Coronavirus outbreak. The disposal of millions of personal protective equipment (PPE) in the form of face masks has significantly contributed to the generation of plastic waste and has exacerbated plastic pollution. In an attempt to mitigate pollution caused by the excess PPE waste, an innovative way was developed in this research to reduce pandemic-generated wastes by using the shredded face mask (SFM) fibers as an additive to hot mix asphalt (HMA) to enhance rutting resistance. Rutting or permanent deformation is one of the major distresses of asphalt pavement. Since the SFM behaves as a semi-liquid between 115.5 and 160 °C, which is in the range of HMA mixing and paving temperature, it can function as a binding agent to glue the aggregates. When the pavement is cooled down to ambient temperature, the hardened SFM can provide stability and stiffness to HMA. Based on the results of this study, the modified mixes exhibited excellent resistance to permanent deformation under the Asphalt Pavement Analyzer (APA), as rutting depth values were reduced from 3.0 mm to 0.93 mm by increasing the SFM content from 0% to 1.5%. From the rutting test results and premature distress mechanism study, the appropriate addition of SFM modifiers could improve the high-temperature properties of HMA that can be used to strengthen high-compression and shearing zones in the pavement structure.

Investigating the properties of cement grouted bituminous mix with alternative grout compositions

Pavements mainly found in urban areas do not last as long as desired and are subject to premature distress. An emerging solution is cementitious material grouted bituminous mix having characteristics in between rigidity and flexibility. This study aims to investigate the properties of cement grouted bituminous mixes with alternative grout compositions. Two alternative grouts are considered where one is composed of ordinary Portland cement, fine sand, silica fume, and water, while the other is composed of ordinary Portland cement, fine sand, fly ash, silica fume, and water. The air void content was kept in the range of 20 to 30% based on compaction effort. Using the Marshall Stability test, the optimum bitumen content of the open graded bituminous mix was determined. Grouting is done manually in a skeleton, allowing the grout to penetrate underneath. It is then cured for three days, seven days, and twenty-eight days at room temperature. To study the detailed behaviour of open-graded cement grouted bituminous mix, Marshall Stability tests, compressive strength tests, indirect tensile strength tests, moisture susceptibility tests, and wheel tracking tests were performed. Results showed that the grouted bituminous mix provided better Marshall Stability, compressive strength, crack resistance, rut resistance, and moisture susceptibility than the conventional mix. It was observed that grouted bituminous mix showed marginal differences in its properties among both grout compositions.

FEATURES OF THE CLINICAL COURSE OF PREGNANCY, CHILDBIRTH IN WOMEN WITH COVID-19 AT DIFFERENT PERIODS OF GESTATION

The study of the features of the clinical course of pregnancy, childbirth in women who have had COVID-19 at different periods of gestation is relevant, especially in the context of a modern pandemic. Purpose of work. To determine the features of the clinical course of pregnancy, childbirth in women with COVID-19 at different periods of gestation. Materials and methods. 57 women who were ill with Covid-19 at different stages of pregnancy were examined. Results and discussion. The peculiarities of the clinical course of pregnancy, childbirth in women who have undergone Covid-19 diseases in the 1st trimesterinclude the syndrome of threatened abortion (73.6 %), placental dysfunction (100%), fetal growth retardation syndrome (42.9 %); in the second trimester - syndrome of threatened premature birth (55.6 %), placental dysfunction (100 %), amniotic fluid pathology (63.2 %); in the third trimester - anemia - in 100 %, antenatal fetal distress - in 42.1 %, pareclampsia - in 47.4 %, pathological blood loss - in 26.3 %. Conclusions. The course of pregnancy and childbirth in women who have undergone COVID-19 diseases in different trimesters of gestation have certain clinical features. Gestational complications in women who were ill in the early stages of the first trimester include the syndrome of threatened abortion, spontaneous abortion, missed abortion, premature birth in the second trimester, fetal growth retardation syndrome in the second and third trimesters. The gestational complications in women who were ill in the second trimester include the syndrome of threatened abortion, premature birth, pathology of amniotic fluid (amniotic fluid of «black» color), the phenomenon of angiitis in the abdominal cavity, placental dysfunction, fetal growth retardation syndrome, distress fetus, antenatal fetal death. The gestational complications in women who were ill in the third trimester include the syndrome of threatened premature birth, placental dysfunction, and fetal distress.

Prediction of Fatigue and Rutting Premature Distress in Linear layered Flexible Pavements for Different Loading Condition using the Mechanistic-Empirical Method

The research aims to study and analyze the damage to asphalt roads and load change based on (KENPAVE) program by evaluating the performance of flexible pavement using the Mechanistic-Empirical Method (M-E). A multi-layered structure for flexible pavement was assumed with load ratios of 50%, 100%, 150%, and 200% of the standard load according to Iraqi specifications. Depend on horizontal tensile strain at the bottom of asphalt layers to estimate the fatigue failure and on the vertical compressive strain above soil layers to estimate the rutting failure. Analysis of the results showed that the highest values of vertical stress were on the single axle in the wearing layer with a value of (639.753 KPa) for standard load, and the raising of load increased the pressure distributed by the vehicle to the pavement so that the tensile and compressive strain was higher. However, the lower tensile and compressive strain values increased both (Nf and Nr). The highest tensile strain values among the layers occurred at asphalt stabilized base coarse of the single axle of (-1.5*10-4) for the standard load. While the highest compressive strain values exist at the top of the subbase layer of the single axle with dual tires of (4.761*10-4) for the standard load. It was also observed that the increasing of axle loads produces an increase in the vertical displacement of the pavement, where the deformation value on the wearing layer of the tandem axle is (0. 8998 mm) for standard load, and that (84%) of this deformation was in the subgrade layer. However, the highest value of damage ratio was existing at the asphalt stabilized base coarse with a value of (0.04426) at standard load. It was also found that the design life decreases by 9 times when increasing the load twice the standard load, which in turn reduces the paving efficiency.

PECULIARITIES OF PREGNANCY COURSE IN WOMEN WITH CONCOMITANT OBESITY WHO TAKE THERAPEUTIC AND PROPHYLACTIC COMPLEX AIMED TO PREVENT PREECLAMPSIA

The rapid growth in the incidence of overweight and obesity among women of childbearing age is posing specific issues related to their pregnancy, thereupon choosing adequate and effective tactics for the prevention of preeclampsia in women with concomitant obesity who are at high risk group for this complication is of undoubted relevance. The aim of this study is to assess the occurrence and characteristic of obstetric and prenatal complications in women with concomitant obesity, who receive therapeutic and prophylactic complex designed to prevent the development of preeclampsia. We studied the course of pregnancy of 255 women, who were divided into 3 groups according to the class of obesity, and then, in turn, were subdivided into subgroups taking into account the presence of preeclampsia and the therapeutic and prophylactic complex course. The high efficiency of the therapeutic and prophylactic complex including L-arginine and diosmin for obese women enables to reduce the manifestations of endothelial dysfunction, the occurrence of preeclampsia and its severe forms; to lower down the occurrence of other complications during the pregnancy (risks of premature birth, placental insufficiency, distress and foetal growth retardation); to avoid perinatal mortality and improve the condition of the foetus. Applying this pathogenetically grounded therapeutic and prophylactic complex we elaborated (acetylsalicylic acid, L-arginine, calcium supplements and semisynthetic diosmin) to prevent the occurrence of preeclampsia in pregnant women with concomitant obesity, who are at high-risk group, promotes the reduction of occurrence and intensity of obstetric and prenatal complications resulted from endothelial dysfunction. We can suggest the therapeutic and prophylactic complex for pregnant women with concomitant obesity as effective therapy because no cases of severe and early preeclampsia have been registered.

Innovative application of waste polyethylene terephthalate (PET) derived additive as an antistripping agent for asphalt mixture: Experimental investigation and molecular dynamics simulation

Moisture-induced damage represents one of the major challenges to the durability of asphalt pavement, which may lead to various premature distresses, such as cracking, ravelling and potholes. To reduce the moisture-induced damages, antistripping agents have been commonly used in asphalt mixtures. On the other hand, the fast-growing waste polyethylene terephthalate (PET) from the end-of-life plastic products poses a serious problem to the environment. How to recycle and reuse the waste PET is becoming a major concern. This study aims to develop a value-added recycling approach of reusing waste PET as an antistripping agent for asphalt mixture. To achieve this objective, waste PET was first collected and went through an aminolysis reaction to yield the amine-based PET additive, which was used to modify bitumen. The infrared spectrum of the PET additive was then characterized, followed by the evaluation of moisture susceptibility through the boiling test and indirect tensile strength (ITS) test. In addition, molecular dynamics (MD) simulation was conducted to analyze the effect of the PET additive on the density and the cohesive energy density (CED) of the binder, and the interface bonding between binder and aggregate at the molecular level. The results from both experiments and MD simulation consistently indicate that the waste PET derived additive can effectively increase the resistance to moisture-induced damage of asphalt mixture.

Experimental study of biopolymer in corrosion resistance for industrial exposure condition

Abstract Many RCC structures have been built in the last century but these structures are in need of repair within 10–20 years of its construction. The reason for this premature distress and deterioration points towards corrosion of steel reinforcement bars used in these structures due to weakening of concrete. The enormous number of structures that needs immediate repair and renovation opens up a huge potential for research in this area. The repair work done in a conventional way using normal cement composite did not work. Whereas repair work done with scientific approach using high and technically competent materials (like epoxies) leads to uneconomical solutions and not durable to withstand our tropical climatic conditions. India being a flourished nation with infinite resources giving us a numerous number of bio-polymers that were used in ancient times in ancient construction, if these bio polymers are identified experimentally for their benefits it would give way to eco-friendly economical and long-lasting structures. The use of corrosion inhibitor is one of the most widely used countermeasures, because of their simplicity in applications and is relatively less expensive. The natural bio polymers are organic materials available from selected plants, seeds, fruit extracts. Plant extracts corrosion inhibitors are cheap, non-toxic and environmental friendly. Organic inhibitors offer protection by adsorbing and forming a protective film on the steel surface. Turmeric, Neem extracts in concrete as corrosion inhibitor in different ratio and as a combination are to be studied at depth, as they are commonly available and there is no constraint in getting these resources throughout the year. An eco-friendly, economical, Non-Toxic and user-friendly corrosion inhibitor can be given from this experimental study. The feasibility study has been made and phytochemical analysis results give positive results for a better result giving corrosion inhibitor.

EVALUATION OF RUTTING PERFORMANCE OF HOT MIX ASPHALT CONTAINING POLYMER ADDITIVES

In recent decades, escalating traffic volumes initiate asphalt pavements revealed to larger stresses, which can create premature distresses. To enhance the resistance to distresses, modification of the asphalt mixtures has been studied extensively. The objective of this paper is to evaluate the performance of asphalt pavement made with various bitumen types and also different thicknesses. The bitumen types used were conventional asphalt (Ac 60-70) and polymer modified asphalt (PG 76-22). The thickness of asphalt samples tested was 70, 80, and 90 mm. In this study, Accelerated Pavement Testing (APT) was conducted to evaluate the rut depth in the surface of the pavement. The experiment was run up to 20,000 cycles. The results revealed polymer has a significant effect on pavement resistance to rutting. The resistance can be increased by up to 30%. In addition, the rutting occurred rapidly for the first 3,000 cycles. Beyond 3,000, the deformation is increased slowly. On the other side, the results showed that as the HMA thickness increases as the resistance to deformation increases. We, therefore, can conclude that adding particles of polymer to HMA could improve the structural performance of pavement i.e. rutting resistance and reduce the thickness of the surface

Effect of centrifuged latex on moisture damage of hot-mix asphalt with brick aggregate

First-class bricks and waste (i.e. overburnt) bricks can be used as a substitute for stone aggregates in asphalt concrete. However, the high porosity of brick aggregate can result in moisture damage, which results in premature distresses in asphalt pavements. In this study, the effect of centrifuged latex (Cenex) on the moisture susceptibility of asphalt mixtures made with overburnt bricks and first-class bricks as aggregate was investigated. Moisture damage tests, such as tensile strength ratio, resilient modulus ratio, retained Marshall stability, boiling water and wheel-tracking tests, were conducted. It was found that the addition of Cenex to the virgin binder improved the mixture resistance against moisture damage for both aggregate mix types. Besides the improvement of moisture damage, the addition of latex also enhanced the rutting resistance and stability of a plain asphalt concrete mix. The work shows that Cenex enhances the performance of brick aggregate asphalt concrete against moisture damage and is an efficient substitution in pavement structures.

Rheological properties of bitumen containing nanoclay and organic warm-mix asphalt additives

In recent years, utilization of warm mix asphalt (WMA) proven to be an environmental way for reducing carbon dioxide emissions in the production and laying process of asphalt mixtures by decreasing the mixing and compaction temperatures. On the other hand, increasing traffic volumes cause asphalt pavements exposed to higher stresses, which could lead to premature distresses. In order to improve the resistance to distresses and alleviate the drawback of WMA mixtures, modification of the bituminous material has grown significantly. In this research, Sasobit as a warm mix asphalt additive and nano-montmorillonite k10 as a bitumen modifier used to modify the 60/70 and 40/50 pen-grade bitumen. The contents of Sasobit were selected are 0%, 2.5%, 3.5% and 4%, while for nano-montmorillonite k10 these percentages are 0%, 2.5%, 3.5% and 5% (by weight of pure bitumen). The objective of this study is to investigate the effect of additives on the conventional and rheological properties of bitumen. To achieve this goal, conventional tests, rotational viscosity (RV), dynamic shear rheometer (DSR), bending beam rheometer (BBR), and direct tension tests were conducted to characterize the properties of pure and modified bitumen. The results indicated that Sasobit has a negligible effect on fatigue and low temperature cracking resistance. Conversely, when increasing the amount of nano-montmorillonite k10, these properties were improved. The results showed that nano-montmorillonite k10 improves the rheological properties of bitumen and reduced drawback effect of Sasobit, especially in low temperature cracking performance.

Fatigue and Rutting Analysis of Asphaltic Pavement Using “KENLAYER” Software

Abstract Rutting and Fatigue are taken as main premature failures among all distresses, as these distresses have wide effect on performance of pavement. Sudden variation of heavy axle loaded vehicles, improper mix design and traditional design methodologies used in pavement design industries are major factors behind these failures. For proper performance and good serviceability, these premature distresses should be resisted. Thus, there is a need of using a Mechanistic based design methodology like KENPAVE software, so that traditional design errors should be overcome. KENLAYER is a part of KENPAVE software. KENLYER software tool is utilized to calculated accurately stresses and strains in asphaltic pavement that are ultimately used in calculating allowance for rutting and fatigue failure utilizing Asphalt Institute design models or formulas. Resistance to Rutting failure is checked by calculating vertical compressive stress at the top of soil sub-grade layer, while resistance to fatigue failure is checked by calculating horizontal tensile strain at the bottom of asphaltic layer using KENLAYER software tool. Thus, the object of this research study is to analyze a flexible pavement with respect to rutting and fatigue distresses using KENLAYER software tool. For achieving that objective NHA (N-55) section of road in Sehwan Pakistan was taken as a reference pavement. Pavement was analyzed by altering the thicknesses of bituminous courses by ± 25 percent. From that we obtained total 20 cross-sections to be analyzed using KENLAYER software in terms of Rutting and Fatigue premature failures.