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Bridge bearings perform the dual function of transferring reaction forces from the super-structure to the sub-structure and facilitating the venting of possible extra stresses that may generate due to restrained deformations. In the present study, the seismic performance of the girder bridges has been investigated as per the provision IRC:6-2017, IS:456-2000, IS 1893 Part (III) 2016, and IRC: SP:114-2019. Two types of bearings have been considered in the study, viz. Elastomeric bearing (EB) and POT PTFE bearings. The design and efficiency of bridges are greatly influenced by the type of bearing adopted and the serviceability of bearings. In past studies, the efficacies of the bearings have not been investigated under the different seismic zone of India. The study presented here focused on parameters that may affect the selection of a particular bearing class and attempted to find the optimum range within which a particular bearing could perform better. Parametric studies have been done by varying span length and pier height under India's different seismic zone. The comparison of seismic performances of POT PTFE and Elastomeric bearings was carried out vis-à-vis the variation in span length, seismic zones and pier height. The provisions of IRC:6-2017, IS:456-2000, and IRC: SP:114-2019 were incorporated to analyze seismic variation for medium-span bridges. It was observed that, the POT PTFE bearings are found better as compared to elastomeric bearing by considering span variation, pier height and seismic zone.

The agricultural pesticide poisoning is currently the most thrust area of human health concern. Pesticide-induced cytotoxicity and the corresponding reproductive toxicity in today's scenario is not a concealed reality that has to be considered for the continuation of respective race. Here, the transmission electron microscopy (TEM) technique was employed to investigate the adverse impact of glyphosate (GLY) and its mitigation by N-acetyl-L-cysteine (NAC) in goat testicular germ cells under in vitro conditions. The ultrastructural observations of testicular tissue from GLY-treated groups at different concentrations (0.1 and 4 mg/ml) and exposure durations (8 and 12 h) revealed that this organophosphate herbicide induced different apoptotic characteristics in testicular germ cells in a time- and dose-dependent manner. However, NAC (10 mM), being a potent antioxidant, was found to mitigate GLY-induced cytotoxicity in testicular cells as evidenced by fewer apoptotic characteristics in GLY plus NAC-treated groups, suggesting its beneficial potential in alleviating the GLY-induced gonadotoxicity in males.Abbreviations: GLY (Glyphosate), NAC (N-acetyl-L-cysteine), TEM (Transmission electron microscopic), GE (genetic engineered), Organophosphate (OPs).

Bituminous pavements are greatly vulnerable to moisture damage. Most of the studies all over the world conclude that presence of moisture on road surface contributes significantly to pavement failures. Sustainable bituminous pavement needs high quality bitumen material. In roadway design, the tensile strength of bituminous pavements is an important engineering property. Indirect tensile strength (ITS) tests are performed on bituminous mixes for evaluating tensile strength ratio (TSR). Knowledge of TSR is helpful in determining the moisture susceptibility of bituminous concrete (BC) mixes for highway pavements. In the past different modelling techniques were developed to predict the TSR of bituminous mixes. In this study, support vector machines (SVM), M5 model tree and regression-based technique were used to estimate the TSR value of BC mixes. Two kernel functions, i.e. polynomial and radial-based kernel function were used with SVM model. Cross validation technique with 10-fold analysis was used for testing the models. SVM model with radial basis function (RBF) outclasses M5P model all in terms of correlation coefficient and R2 values. This paper proposes a simple linear equation for the prediction of the TSR, which is based on ITS tests performed on different types of bituminous mixes.

Due to increased industrialization, large amount of industrial by-products are produced every year in all parts of the world. Disposal of these often toxic wastes is the major problem faced and can potentially be solved by their use in the construction industry. The main aim of this study was to utilize the argon oxygen decarburization (AOD) steel slag (a waste product from the stainless steel industry) in the concrete mix for construction of rigid pavements. The present study evaluated various properties of concrete mixes containing 0–25% of AOD steel slag as a partial replacement of ordinary portland cement and further curing the mixes for 28, 90, 180 and 365 days. Thus, the study investigated the compressive and flexural strengths, abrasion resistance, resistance to acid attack and resistance to sulfate attack of concrete mixes. Further, scanning electron microscope, energy-dispersive X-ray spectroscopy and toxicity characteristic leaching potential (TCLP) analyses were also conducted to study the micro-structural properties and leaching characteristics of steel slag mixed concrete. Compressive and flexural strength showed the positive results as the curing period of the specimens increased. Durability properties were less affected by the addition of AOD steel slag. TCLP analysis revealed that the toxicity of steel slag concrete was found within the permissible limits as compared to the raw steel slag. Further, to approximate the underlying relationship existing between the input–output data, a Legendre functional link neural network has been implemented for the prediction of compressive and flexural strengths.

This study emphasis on determining the tensile strength ratio (TSR) of bituminous concrete (BC) mixes to check their moisture susceptibility. Two types of bitumen VG30 and CRMB55 were used for preparing the BC mixes. Indirect tensile strength (ITS) test was performed as per AASHTO T283 standard on BC mixes. BC mixes were subjected to multiple freeze-thaw cycles to examine the effect of increased adverse conditions. It was noticed that BC mixes prepared with VG30 bitumen failed to meet the 80% TSR value criteria. However, BC mixes prepared with CRMB55 bitumen exhibited superior resistance to moisture damage. Hydrated lime and organosilane based adhesion promoter (OSAP) has been used as anti-stripping agents (ASAs) to increase the resistance of BC mixes to moisture damage in this study. The results show that hydrated lime and organosilane based adhesion promoter enhances the performance of BC mixes for multiple freeze-thaw cycles also. The potential of data mining techniques like regression technique for predicting the tensile strength ratio (TSR) have also been explored for developing model for the same.

In this paper, an attempt has been made to apply and compare the prediction capability of two variants of Artificial Neural Networks: feed-forward neural network (FFNN) and the radial basis functio...

In the present study, we have used feed-forward neural network (FFNN) for the prediction of compressive and flexural strength of steel slag mixed concrete for pavements. The compressive and flexural strength of the specimens were examined experimentally for the specimens consisting of 0, 10, 15, 20 and 25% Argon Oxygen Decarburization (AOD) steel slag as a partial replacement of cement in M40 concrete mix. The curing of specimens was done for 3, 7, 28, 90, 180 and 365 days and thus accounting for the total of 90 observations. Both the output parameters were dependent upon 8 input parameters. To evaluate the performance of the FFNN model, we have used Mean Squared Error (MSE) and Mean Average Error (MAE) as the performance indicators.

In the present paper, we have applied a Legendre Functional Link Neural Network (LeFLNN) to predict the compressive and flexural strength of jarosite added concrete for pavements. The cement is replaced partially by the jarosite in different percentages like 0, 10, 15, 20, and 25%. The specimens prepared using various proportions of jarosite were subjected to curing for 3, 7, 28, 90, 180, and 365 days. The proposed model parameters are trained using the back-propagation (BP) method. Total of 90 experimental observations (input–output data) is obtained from which 70 observations are used for the training and the rest 20 observations are used for validating the trained LeFLNN model. The results obtained in the simulation study show the efficacy of the proposed method.

The purpose of the present study is to deal with the potential application of jarosite, a waste material produced during the extraction of zinc ore concentrate using the hydro metallurgy operation, in the production of the concrete. The method involves a total of five mixes including the control mix which was prepared by partially replacing the cement by the jarosite varying from 10, 15, 20 and 25%. It was noticed that incorporation of jarosite did not much alter the fresh concrete properties, as it was well within the desired range. The present laboratory investigation results also confirmed that as the percentage of jarosite in the concrete mix was increased, the mechanical properties of the concrete tend to decrease gradually but can be improved further by adding mineral and chemical admixtures. Further, the water absorption properties were also got improved. Other durability properties like acid attack, chlorine resistance and abrasion loss were found to decrease as the percentage of the jarosite in the concrete mix was increased. From the study, it can be concluded that, up to 15% of jarosite can be used as the replacement of the cement in the construction of the highways. Higher percentage of the jarosite can be used for low traffic volume or village roads for the safe disposal and reuse of the industrial waste.

Pavement construction tends to be relatively expensive in areas where subgrade soil is poor. Improvement in soil properties by replacement of the poor subgrade soil may not always be an economical solution. Keeping this into consideration, an experimental study was carried out on three types of fine-grained soil to demonstrate an economical solution by mechanical stabilization of the subgrade soil with stabilizers such as coarse aggregate of 10 mm size and stone dust. The effect of mechanical stabilization on Maximum Dry Density (MDD), Optimum Moisture Content (OMC) and California Bearing Ratio (CBR) was investigated. The study revealed that on the addition of the stabilizers with subgrade soil, the CBR value and MDD increased while OMC decreased. IRC: 37-2012, the standard for the thickness design of flexible pavements in India, specifies the use of select soil of minimum CBR 8.0% when traffic on the road is 450 commercial vehicles per day or higher. This desired value of CBR under soaked condition was obtained by the addition of 30% stone dust, or 20% of 10 mm size coarse aggregate, or 10% stone dust + 10% coarse aggregate of 10 mm size by mass of dry soil. This mechanical stabilization resulted in increase in soaked CBR value by 32.4%–194.7% for three types of fine-grained soils considered in the study. The mechanical stabilization with coarse aggregate or stone dust is also found to be more economical as compared to replacement of the soil with good soil of desired CBR value by more than 50%.

This work examines the application of M5 model tree and conventionally used fixed/random effect negative binomial (FENB/RENB) regression models for accident prediction on non-urban sections of highway in Haryana (India). Road accident data for a period of 2-6 years on different sections of 8 National and State Highways in Haryana was collected from police records. Data related to road geometry, traffic and road environment related variables was collected through field studies. Total two hundred and twenty two data points were gathered by dividing highways into sections with certain uniform geometric characteristics. For prediction of accident frequencies using fifteen input parameters, two modeling approaches: FENB/RENB regression and M5 model tree were used. Results suggest that both models perform comparably well in terms of correlation coefficient and root mean square error values. M5 model tree provides simple linear equations that are easy to interpret and provide better insight, indicating that this approach can effectively be used as an alternative to RENB approach if the sole purpose is to predict motor vehicle crashes. Sensitivity analysis using M5 model tree also suggests that its results reflect the physical conditions. Both models clearly indicate that to improve safety on Indian highways minor accesses to the highways need to be properly designed and controlled, the service roads to be made functional and dispersion of speeds is to be brought down.

It is generally believed that increase in subgrade strength leads to decrease in the thickness of a rigid pavement which helps in reducing the cost of pavement. The guidelines of Indian Roads Congress (IRC) for the design of rigid pavements also recommend the use of select soil of minimum CBR 8% in the subgrade for design of cement concrete pavement for roads having traffic greater than 450 CVPD. An attempt has been made in this paper to study the effect of variation in subgrade strength on thickness and cost of a rigid pavement. It is found that the thickness and cost of pavement may not decrease with an increase in the strength of subgrade soil. The provision of using select soil of minimum CBR 8% in the subgrade of the road as recommended by IRC, therefore, needs to be applied carefully.

The main objective of the present study was to investigate the utilization of zinc industry waste (jarosite) in the production of concrete by replacing it with the cement. The properties of the jarosite mixed concrete, in which the jarosite had partially replaced (0, 10, 15, 20 and 25%) the Ordinary Portland Cement (OPC), were also studied. Compressive and flexural strengths, abrasion resistance, air permeability and sorptivity of concrete mixes were also investigated after the curing periods of 28, 90, 180 and 365 days. Further, SEM, EDS and TCLP analysis were conducted to study the micro-structural properties and leaching characteristics of jarosite mixed concrete. From the experimental results it was found that the compressive and flexural strengths showed significant improvement when the curing period of the specimens was increased. Air permeability and sorptivity tests had given best results when the cement was replaced by 25% of jarosite. Further, the TCLP analysis revealed that toxicity of the jarosite concrete was found within permissible limits as compared to the raw jarosite.

Roads play a vital role in the development of a country. A good network of highways is important as it helps in the development of trade, commerce and other activities that characterise a vibrant and forward-looking nation. As from the recent past years, India is shifting toward the construction of rigid pavements, and it is high time that all the factors that affect the economy of its construction should be taken into consideration. One of the main factors is the type of shoulders provided. Even a small decrease in the thickness of pavement leads to an appreciable saving of the material used in its construction, thereby affecting the economy of the project. Therefore, an attempt has been made to design a two-lane two-way National Highway proposed to be laid in Haryana by considering various types of shoulders, viz., tied concrete shoulders and earthen shoulders. It is observed that by providing tied concrete shoulder, there is an appreciable reduction in the slab thickness appreciably which affects the economy of project, thereby attaining the goals of sustainable development in an effective manner.

Improper drainage facilities on a road can cause failure of its pavement. Accumulation of water on roads during monsoon/rains causes inconvenient and retarded traffic movement. It can result in loss of adhesive bond between aggregate and bitumen on the road surface resulting into stripping and threatens the durability of roads. Proper drainage system with adequate section of storm water drains can ensure the safety against above aspects. In this paper effect of poor drainage system on road pavement and adequacy of storm water drain on a stretch of NH-1 has been studied. It is found that the size/capacity of drain is sufficient but it is not able to drain the water due to poor maintenance of drains and adverse slope of the ground between drain and the road. It is also found that stripping value of bituminous mix increases with the increase in immersion time of aggregate in water.

Summary The present study deals with the characteristics and trend of road accidents on a selected stretch of NH-1 between RD 98 km and 148 km. Four year road accident data from 2007 to 2010 of 50 km long stretch was collected which includes the period when construction of 6-laning project started on NH-1. The paper also brings forth the result of widening project on road accidents. The data was analyzed to identify cause of accidents, nature of accidents and type of injury, type of vehicles involved and time of accidents. The widening project has resulted in tremendous increase in number of accidents on the road. Maximum accidents fall in the category of non-injury type (49%). Serious injury type accidents are found to be more than fatal accidents. Findings show that head on/rear end collisions, caused mainly due to overspeeding/driver's fault account for 46% of the accidents. It is seen that trucks/canter/buses are found involved in maximum number of accidents (42%). The day time accidents are found to be more than night time accidents. This paper presents the data analysis, improvement measures and conclusions recommendations to reduce road accidents on NH-1.

With an increased industrialisation, production of industrial by-products has risen significantly. Numerous types of waste materials are generated from the manufacturing processes. Jarosite is one of the by-products generated from the zinc manufacturing industry and its disposal is of major concern because it contains various toxic elements like oxide of iron, nickel, arsenic and lead. The construction industry needs to be transformed into a sustainable and environmental friendly from being consumption-based. Therefore, jarosite is very useful in the design and development of the cement concrete and other composites. This paper presents a detailed and comprehensive review about the physical, chemical and geotechnical properties of the jarosite waste. It also covers properties of the fresh concrete containing jarosite, its compressive and flexural strength, leachate characteristics, chloride resistance and water absorption of the cement concrete mixed with the jarosite.

The present study emphasizes the potential use of Argon Oxygen Decarburization (AOD) steel slag in concrete production. Five mixes along with the control mix were made by partially replacing cement with AOD steel slag varying from 10%, 15%, 20%, and 25%. The different properties of all the concrete mixes were evaluated by assessing slump, compressive strength, flexural strength and other durability properties. The air permeability index and sorptivity index showed positive results with an increased percentage of AOD steel slag in the mixes. From the study, it is concluded that AOD steel slag can easily be replaced by cement in the construction of rigid pavements. Further, we have also constructed a Feed-Forward Neural Network (FFNN) to predict the compressive and the flexural strengths of steel slag mixed cement concrete for pavements.

Accumulation of rainwater on roads due to lack of proper drainage causes loss of adhesive bond between bitumen and aggregate which results into stripping and severe damage to the pavement. Indian Standard (IS 6241-1971: method of test for determination of stripping value of road aggregate. Laboratory test, 1971) [1] prescribes the stripping test in which aggregate coated with bitumen is kept immersed in water for 24 h at 40 °C. After the test, the retained coating of bitumen should be minimum 95% for the aggregate to be suitable for road construction. Most of the time, the aggregate exhibits no stripping under laboratory conditions, whereas it fails in stripping under field conditions. To understand this problem, a laboratory investigation was conducted on the aggregate of Haryana taking into consideration some of the prevailing field conditions like acidic/alkaline nature of water and the presence of traffic on the roads. The test results indicated that the pH of water and application of external pressure affected the stripping considerably.