Simplified Approach for Structural Evaluation of Flexible Pavements at the Network Level

Currently, there is no simple procedure available to identify structurally weak pavement sections using Falling Weight Deflectometer (FWD) data at the network level (e.g., city, state or province). A simple method is needed to determine the structural condition of pavement sections that can be directly implemented and automated in the current pavement databases. The method needs to be simple enough to be used with a network level FWD database for the purpose of numerically ranking pavement sections at the network level from good to poor. Backcalculation has been utilized to obtain layer moduli and determine overlay (new added surface pavement layer) thickness at the project level. However, the use of the backcalculation technique at the network level is complicated and time consuming, which makes it not practical for network level pavement sections assessment. The objective of this research study is to develop a simple analysis method to determine the structural condition of pavements using currently available non-destructive testing (NDT) deflection measurement devices at the network level that can be directly implemented and automated in the database of a typical transportation agency (such as TxDOT). In addition, this proposed study aims to run an advanced 3D-Move simulation analyses to mimic the FWD deflection bowl obtained from the field in an effort, for the first time, to reduce the need to run extensive FWD testing on the network level. The proposed deflection and area ratio parameters will serve as indicators of the pavement structure’s capacity to carry heavy traffic. In addition, deflection and area ratio parameters will help with the overall evaluation of the health of the road network and the determination of the remaining life of individual road segments. This will allow transportation officials to obtain a clearer view of the state of the network. Therefore, they can have more accurate estimation of the required funds to maintain the highway network at a certain desired level. With this approach, more informed decisions about the most suitable maintenance and rehabilitation strategies can be made. Since the deflection data that are commonly collected by the agency will be utilized in this approach, the approach will be economically feasible. The developed single and overall parameter, CAr’ was well related to the number of load repetitions to fatigue failure, Nf, with a coefficient of determination, R2 of 0.96. The single parameter can be easily implemented in the PMS databases and thus, CAr’ will help the South-Central state DOTs and local highway agency officials to make more informed decisions about the most suitable maintenance and rehabilitation strategies

Prediction of average annual surface temperature for both flexible and rigid pavements

The surface temperature of pavements is a critical attribute during pavement design. Surface temperature must be measured at locations of interest based on time-consuming field tests. The key idea of this study is to develop a temperature profile model to predict the surface temperature of flexible and rigid pavements based on weather parameters. Determination of surface temperature with traditional techniques and sensors are replaced by a newly developed method. The method includes the development of a regression model to predict the average annual surface temperature based on weather parameters such as ambient air temperature, relative humidity, wind speed, and precipitation. Detailed information about temperature and other parameters are extracted from the Federal Highway Administration's (FHWA) Long Term Pavement Performance (LTPP) online database. The study was conducted on 61 pavement sections in the state of Alabama for a 10-year period. The developed model would predict the average annual surface temperature based on the known weather parameters. The predicted surface temperature model for asphalt pavements was very reliable and can be utilized while designing a pavement. The study was also conducted on seven rigid pavement sections in Alabama to predict their surface temperature, in which a successful model was developed. The outcome of this study would help the transportation agencies by saving time and effort invested in expensive field tests to measure the surface temperature of pavements

Development of Deflection Parameters to Evaluate the Structural Capacity of Flexible Pavements at the Network Level: Case Study for the State of Texas

Pavement deflection has been used widely as a nondestructive technique to evaluate the structural capacity of pavements at both network and project levels. Various transportation agencies use several evaluation methods to evaluate the integrity of the pavement layers. Most of these up-to-date developed indices are exclusively based on either central deflections or one deflection point along FWD deflection bowl. However, no standardized method that utilizes the full FWD deflection bowl is available. This study aims to introduce new comprehensive pavement layer deflection and deflection bowl area parameters that are based on the entire FWD deflection bowl rather than one single deflection point and to relate the developed parameters to the field measured distress data. Thirty-five different pavement sections in the State of Texas were utilized in the study. Two comprehensive deflection parameters and a ranking scale were developed that may be utilized for the overall pavement structural condition evaluation

Analysis of a Cashew Shell and Fly Ash Rich Brake Liner Composite Material

Hybrid materials collected from organic and inorganic sources, which are traditionally used as brake lining mate- rials, generally include fly ash, cashew shell powder, phenolic resins, aluminium wool, barites, lime powder, car- bon powder and copper powder. The present research focuses on the specific effects produced by fly ash and aims to provide useful indications for the replacement of asbestos due to the health hazards caused by the related fibers. Furthermore, the financial implications related to the use of large-volume use of fly ash, lime stone and cashew shell powder, readily available in most countries in the world, are also discussed. It is shown that many manu- facturing and automotive industries, which are currently experiencing difficulties in meeting the increasing demand for brake lining material, may take advantage from the proposed solution

A novel homozygous TPM1 mutation in familial pediatric hypertrophic cardiomyopathy and in silico screening of potential targeting drugs.

Familial hypertrophic cardiomyopathy (HCM) is the most common genetic cardiac disease. While sarcomeric gene mutations explain many HCM cases, the genetic basis of about half of HCM cases remains elusive. Here we aimed to identify the gene causing HCM in a non-consanguineous Saudi Arabian family with affected family members and a history of sudden death. The impact of the identified mutation on protein structure and potential drug targets were evaluated in silico. Triplets (two HCM subjects and one patent ductus arteriosus (PDA) case) and unaffected parents were screened by targeted next-generation sequencing (NGS) for 181 candidate cardiomyopathy genes. In silico structural and functional analyses, including protein modeling, structure prediction, drug screening, drug binding, and dynamic simulations were performed to explore the potential pathogenicity of the variant and to identify candidate drugs. A homozygous missense mutation in exon 1 of TMP1 (assembly GRCh37-chr15: 63340781; G>A) was identified in the triplets [two HCM and one patent ductus arteriosus (PDA)] that substituted glycine for arginine at codon 3 (p.Gly3Arg). The parents were heterozygous for the variant. The mutation was predicted to cause a significant and deleterious change in the TPM1 protein structure that slightly affected drug binding, stability, and conformation. In addition, we identified several putative TPM1-targeting drugs through structure-based in silico screening. TPM1 mutations are a common cause of HCM and other congenital heart defects. To date, TPM1 has not been associated with isolated PDA; to our knowledge, this is the first report of the homozygous missense variation p.Gly3Arg in TPM1 associated with familial autosomal recessive pediatric HCM and PDA. The identified candidate TPM1 inhibitors warrant further prospective investigation.This research was supported by the Strategic Technologies Programs of the National Plan for Science, Technology and Innovation (MAARIFAH), Kingdom of Saudi Arabia. Project No: 12-MED3174-05, through the Science and Technology Unit (STU), Taibah University, Al Madinah Al Munawwarah, Kingdom of Saudi Arabia

Environmental Emission of Pharmaceuticals from Wastewater Treatment Plants in the USA

The residual drugs, drug bioconjugates, and their metabolites, mostly from human and veterinary usage, are routinely flushed down the drain, and enter wastewater treatment plants (WWTP). Increasing population, excessive use of allopathic medicine, continual introduction of novel drugs, and existing inefficient wastewater treatment processes result in the discharge of large volumes of pharmaceuticals and their metabolites from the WWTPs into the environment. The effluent from the WWTPs globally contaminate ~25% of rivers and the lakes. Pharmaceuticals in the environment, as contaminants of emerging concerns, behave as pseudo-persistent despite their relatively short environmental half-lives in the environment. Therefore, residual levels of pharmaceuticals in the environment not only pose a threat to the wildlife but also affect human health through contaminated food and drinking water. This chapter highlights WWTPs as point-sources of their environmental emissions and various effects on the aquatic and terrestrial ecosystem

Machining studies on Monel K − 500 using TiAlN coated tungsten carbide inserts under Ag nanoparticles incorporated modified pongamia pinnata oil lubrication

Research investigations conducted in the past has shown that conventional petroleum based lubricants can be replaced with vegetable lubricants. Vegetable oil lubricants do not pollute the environment, as they are biodegradable. In this investigation, pongamia pinnata oil was used as lubricant, to during turning experiments. The physico chemical properties of modified pongamia pinnata oil were evaluated. Ag Nanoparticles were incorporated into the modified pongamia pinnata oil and it was subjected to tribological investigations. In this investigation, the effect of Ag nanoparticles in improving the lubricating aspects of the modified pongamia pinnata oil was studied. The aim of this investigation is to identify the effect of the nanoparticle incorporated bio- lubricant coolant on Monel K 500. In this study, using TiAlN coated triangular tungsten carbide inserts, Monel K 500 was subjected to turning under three conditions such as dry, minimum quantity lubrication and Ag nanoparticles incorporated vegetable oil lubrication. It was observed that the properties of the bio lubricant affected the turning output responses to such as cutting force, machining temperature, tool wear and surface roughness of the workpiece (Monel K 500). Machined surface was evaluated using scanning electron microscope, electron back scatter diffraction analysis and x-ray diffraction analysis. Turning operation conducted with 2% Ag nanoparticles incorporated modified pongamia pinnata oil lubrication was better than turning conducted under dry and lubricated conditions. Industrial wastes and toxic effluents can be minimised by switching over to bio lubricants and coolants

Analyzing the factors affecting construction project schedules amidst COVID-19 pandemic

The global health crisis caused by the COVID-19 pandemic led to disruptions and challenges across many business sectors, including the construction industry. A serious ramification of the pandemic on the construction industry was an increase in the number of project schedule delays that affected a multitude of projects around the world. Although the current literature explores the factors that cause project schedule delays, little research is available on the impact of variables, such as the size of the industry, type of project, and category of the organization, on the delays. This study used a four-step approach to address this knowledge gap by performing a comprehensive literature search, developing a survey, distributing the survey online, and conducting a quantitative analysis of the responses. The study's findings revealed that the factors contributing to project schedule overruns during the pandemic were diverse and differed with the variables cited above. Distinct differences were observed in areas such as procurement of materials and changes in material specifications and prices. This research sheds light on the multifaceted nature of the variables that impacted construction project schedules during the COVID-19 pandemic and provides valuable insights for industry stakeholders as they seek to establish effective strategies that will minimize risks and enhance project delivery during future periods of crisis

Electrochemical Micromachining of Stainless Steel with Acidified Sodium Nitrate Electrolyte

AbstractThis paper describes Electrochemical Micromachining (EMM) of stainless steel with acidified sodium nitrate. The sulphuric acid of 0.05m/L is added to the standard electrolyte namely sodium nitrate to solubilise the by-products. The foremost characteristics of EMM are researched through scheme of experiments involving various parameters, such as machining voltage, pulse on time and electrolyte concentration. The performance of acidified sodium nitrate and sodium nitrate on EMM are compared. Based on the study, the machining rate and overcut are significantly improved using acidified sodium nitrate as an electrolyte

A Review on Construction Safety: Hazards, Mitigation Strategies, and Impacted Sectors

Hazard identification is a fundamental step in safety management that has the potential to reduce the number and severity of occupational injuries on construction sites. Researchers have identified and evaluated some of the hazards, but few have extensively discussed all of them and none have classified them by sector. The goal of this paper is to fill that research gap by considering hazard identification through an organized synthesis of the existing literature. After a comprehensive literature review, 236 publications were deemed eligible for further analysis. Eighteen safety hazards were identified and then categorized into four groups based on their physiological impacts, ranked based on frequency of citation, and classified by sector. The results revealed that falls from heights, material handling, and heavy machinery were the most frequently cited hazards and the most likely to impact all sectors. Mitigation strategies were also identified, and it was determined that most hazards can be mitigated through the use of personal protective equipment, and effective training and supervision