Search results

WHEN oil refiners have refined about as far as they can, they are left with a residue — bitumen. Its properties and character vary with the crude oil being refined. The bitumen producer blends and treats different raw bitumens to produce three main types for use in industry. In addition, oil company subsidiaries and independents process the bitumens to produce bitumen emulsions, bituminous mastics, and bituminous solutions and in latter years homogeneous blends of bitumen with resins and other materials. Such processed materials can be used as adhesives, sealants, waterproofing materials, flooring and road surfacing binders, insulation accessories, and general waterproofing and building protection coatings, quite apart from their widespread use in industrial processes.

The purpose of this paper is to study the recent work carried out in enhancing the properties of bitumen using nano-additives. Bitumen is a by-product obtained from the refining process of crude oil, therefore making it a diminishing product. It has been used by mankind since ages for various applications like sealants, binders, waterproof coatings and pavement construction material. It is a black viscous substance with adhesive nature.

Bitumen is used as a binding material because of its ability to become liquid when heated and become solid when cooled and thus used largely in construction of roads because of its unique properties. Low softening point of bitumen leads to melting of bitumen during summer and causes rutting of roads, whereas during winter it leads to cracking as bitumen acts brittle in nature during low temperature. Increasing global demand of bitumen has created gap between demand and supply which is increasing with the passage of time. Further modern life has created very high traffic volume and heavy load which makes it essential to improve performance of bitumen.

Research studies have reported that the thermal properties of bitumen are enhanced by using thermoplastic polymers such as styrene-butadiene-styrene, polyethylene and ethylene-vinyl acetate, rubber and bio waste etc.

This paper reviews various types of materials which have been used to improve the properties of bitumen and explores the possibility to synthesise bitumen composite materials with nanoadditives with improved structural, mechanical and thermal properties.

This paper aims to examine the quality of the surface waters of the bitumen deposit area of Nigeria and also to establish the relationship between the deposit and the waters.

Physico-chemical parameters were measured using standard analytical procedures, while the elemental contents were determined using total reflection X-ray fluorescence spectroscopy. Data acquired were interpreted using statistical techniques – charts, t-test, pollution index (PI) and cross-plot analysis.

A river located close to the bitumen well contained the highest concentrations of metals that are known to be associated with hydrocarbon formation. Comparison of the levels of the analyzed parameters in the waters with their standard permissible limits showed that the levels of Cl−, SO₄2-, total alkalinity and Cr, Mn, Fe, Ni, Cu, Zn and Pb in the river very close to the capped bitumen well and big rivers were high and low in the small streams. This was corroborated by their pollution index values. Results of the cross-plot analysis of the waters-river close to bitumen well/bitumen (R2=0.5); small streams/bitumen (R2=0.8) and big rivers/bitumen (R2=0.2) showed moderate; strong and weak positive correlations respectively, suggesting moderate, strong and weak inter-element correlations respectively between the sets of waters and the Nigerian bitumen deposit, and also establishing relationships between the deposit and the surface waters.

The paper provides insight into the potability of the waters; establishment of the inter-element relationship between the bitumen deposit and the waters. These results can serve as a fingerprint for bitumen exploration elsewhere and for similar mineral deposit settings.

Bitumen has long been used as a waterproofing material and as a protective coating for all types of surfaces exposed to the weather. It has been stated that the deliberate use of bitumen for preservation purposes dates back to about 3,800 B.C., so there is nothing novel in the use of this raw material. Bitumen is such a versatile commodity that new applications and modifications are constantly being developed and utilised in the protection of structures of all types.

Construction materials comprise a major part of the total construction cost. Given the importance of bitumen as a fundamental material in construction projects, it is imperative to have an accurate forecast of its consumption in the planning and material sourcing phases on the project. This study aims to introduce a flexible genetic algorithm-fuzzy regression approach for forecasting the future bitumen consumption.

In the proposed approach, the parameter tuning process is performed on all parameters of genetic algorithm (GA), and the finest coefficients with minimum errors are identified. Moreover, the fuzzy regression (FR) model is used for estimation. Analysis of variance (ANOVA) is used for selecting among GA, FR or conventional regression (CR). To show the applicability of the proposed approach, Iran’s bitumen consumption data in the period of 1991-2006 are used as a case study.

Production, import, export, road construction and price are considered as the input data used in the present study. It was concluded that, among all the forecasting methods used in this study, GA was the best method for estimating.

The proposed approach outperforms the conventional forecasting methods for the case of bitumen which is a fundamental economic ingredient in road construction projects. This approach is flexible, in terms of amount and uncertainty of the input data, and can be easily adapted for forecasting other materials and in different construction projects. It can have important implications for the managers and policy makers in the construction market where accurate estimation of the raw material demand is crucial.

This is the first in this field introducing a flexible GA-FR approach for improving bitumen consumption estimation in the construction literature. The proposed approach’s significance has two folds. Firstly, it is completely flexible. Secondly, it uses CRs as an alternative approach for estimation because of its dynamic structure.

Bituminous paints may be divided into two main classes; those of petroleum origin and those of coal tar origin. Although the unqualified term ‘bitumen’ is usually understood to refer specifically to asphaltic bitumen, the word ‘bituminous’ is habitually used to describe both surface coatings deriving from coal tar and those based on bitumen.

The aim of this study is to understand the environmental benefits and economic savings associated with adoption of circular economy in the construction sector. The research findings will support different stakeholders and decision makers to develop business models based on responsible consumption of resources and build sustainable business models.

The research uses mixed methodology wherein inventory for life cycle assessment and life cycle costing for environmental and economic impacts is based on primary data using on-site visits for qualitative and quantitative data.

Different types of land transportation infrastructures are compared for their environmental impacts. It is found that bridges have the highest environmental impacts as compared to tunnels, roads and railways. Further, the results affirm the environmental and economic benefits of adopting circular economy practices.

This is one of a kind research that compares the environmental and economic tradeoffs of adopting circular economy in different types of land transportation infrastructures.

Copolymer resins of peanut skin tannin extract, aldehydes and cashew nut shell liquid were prepared. The resins were blended with bitumen and used in formulating oleoresinous wood varnishes. The film properties of the varnishes were determined and the results showed that the gloss and scratch hardness of the films increased with increase in the quantity of cashew nut shell liquid/tannin‐aldehyde resins incorporated. The results also showed that the resins improved the chemical resistance of the varnish films. Varnish compositions containing 50:50 of bitumen and the resins gave films with satisfactory physical and chemical properties. The study showed that it is possible to formulate excellent oleoresinous wood varnishes using blends of bitumen and cashew nut shell liquid/tannin‐aldehyde resins.

It is on record that asphalt in one form or another was used by the Sumerians about 3800 B.C. and there are numerous references in technical literature crosslinking the terms asphalt and bitumen. The increasing use and success of bituminous substances through the ages as protective coatings or as jointing and fixing compounds are vividly described in Abraham’s fascinating work “Asphalt and Allied Substances” Perhaps the best recommendation which can be given for the efficiency of bitumen as a protective medium is the excellent state of preservation of specimens treated with bitumen still being unearthed by archaeologists.

Natural good-quality sources of aggregates are depleting, whereas large amount of reclaimed asphalt pavement (RAP) is produced annually. Safe disposal and use of RAP in the cold in-place recycling (CIR) using foamed bitumen could be sustainable approach where milling and mixing operations are accomplished simultaneously. This will not only help in minimizing contamination (probability) and transportation cost but also reduces the carbon footprints. Therefore, this study aims to investigate the scope of RAP utilization up to 100% and further its effect on the behavior of reclaimed asphalt foamed bituminous mix.

Reclaimed asphalt foamed bituminous mix (FBM) is still a new technique. The evidence of performance of 100% recycled pavement (CIR) is only anecdotal and lacks in systematic guidelines and literatures. Foam binder coating around the aggregates is also a concern. Therefore, this study is mainly emphasized to investigate the scope of RAP use in the FBM up to 100%. RAP content is varied in each trial, i.e. 70, 85, 100 and 0% (only fresh aggregates), to make the FBM. RAP use and its effect on the behavior of FBM in terms of resilient modulus, variation in resilient modulus with curing, rutting performance and the potential of resistance against the moisture damage are addressed.

Considering the laboratory studies, it can be accomplished that mechanistic properties and performance of FBM are largely influenced by RAP material and portray less susceptible characteristics against the moisture damage. FBM containing 70% RAP content exhibits maximum resilient modulus. However, use of RAP up to 100% in FBM is satisfying the minimum required specification.

Overall, the study may be helpful to highway professionals and could generate another possible option of 100% RAP replacing fresh aggregates in the flexible pavements.