Bituminous Emulsion Mixtures Research Articles

Investigating the Impact of Polymer and Portland Cement on the Crack Resistance of Half-Warm Bituminous Emulsion Mixtures

Cold mix asphalt (CMA) is emerging as an environmentally friendly alternative to traditional hot mix asphalt (HMA). It offers advantages such as lower costs, reduced energy demands, decreased environmental impacts, and improved safety aspects. Among the various types of CMA, the cold bitumen emulsion mixture (CBEM) stands out. The CBEM involves diluting bitumen through emulsification, resulting in lower bitumen viscosity. However, this process has certain drawbacks, including extended setting (curing) times, lower early strength, increased porosity, and susceptibility to moisture. This study focuses on enhancing CBEM properties through the utilization of low-energy heat techniques, such as microwave technology, and the incorporation of a polymeric additive, specifically acrylic. These innovations led to the development of a novel paving technology known as a half-warm bitumen emulsion mixture (HWBEM). The research was conducted in two phases. First, the study assessed the impact of low-energy heating on the CBEM. Subsequently, it explored the combined effects of low-energy heating and the addition of an acrylic polymer. CBEM samples containing ordinary Portland cement (OPC) as an active filler were utilized in the sample manufacturing process. The effectiveness of these techniques in enhancing crack resistance was evaluated by analysing the results of the indirect tensile strength test. Notably, CBEM samples containing an amount of 2.5% of acrylic polymer and OPC exhibited the highest resistance to cracking. Furthermore, significant improvements were observed in their volumetric and mechanical properties, comparable to those of HMA.

Microstructure Analysis of Cold Bituminous Emulsion Mixture Using Different Filler Type

Abstract In today’s scenario, the environmental impact of the transport sector plays a major role in net carbon emission generation and global warming. Seeing the emerging environmental issue, it has been mandatory to adopt sustainable technologies in every sector. The use of bitumen emulsion in the construction of pavement has been rapidly enhanced in the last decade. This technology eliminates the heating of aggregate and binder, resulting in a reduction of greenhouse gas emissions and energy consumption, which is also termed as cold mix technology. Filler has a major role in the formation of bonds between bitumen emulsion and aggregate. In the present study, cement, lime, and fly ash have been considered as filler materials along with stone dust and the required optimum emulsion content and water content were determined. The impact of filler on the breaking of bitumen emulsion is studied through scanning electron microscope image analysis. The impact of filler on pH of bitumen emulsion mastic is also evaluated. The optimum emulsion content in cold bituminous emulsion mixtures (CBEMs) depends on the particle size of the filler. The required water content for lime is less compared to other filler materials. The results show that cement and fly ash are pozzolanic in nature, form hydration products in the presence of water in CBEM, and result in higher density and stability. The study depicts the role of filler material in CBEM at the microlevel.

Recycled concrete aggregate incorporated cold bituminous emulsion mixture: Mechanical, environmental and economic evaluation

The present study aims at exploring the effect of partially replacing virgin aggregates with recycled concrete aggregate (RCA) in cold bituminous emulsion mixture (CBEM). In the study different CBEM samples were prepared by replacing 10–50% virgin aggregates with RCA. These samples were tested for mechanical properties and moisture susceptibility parameters such as Marshall Stability, Marshall Quotient (MQ), Indirect Tensile Strength (ITS), Retained Stability (RS) and Tensile Strength Ratio (TSR). In order to deal with CBEM's inherent issues like lower strength, higher air voids, higher moisture susceptibility, apart from conventional stone dust filler two additional fillers lime and cement were also used. Environmental and economic analysis of all the samples were also carried out by calculating the cost and CO2-eq of the mixtures. Test results showed that RCA incorporation in CBEM has positive impact on the properties like Marshall Stability, MQ and ITS while it has negative impact on the moisture susceptibility. Inclusion of lime and cement fillers solved the issues related with moisture susceptibility. Further based upon the economic and environmental analysis it was found that RCA incorporated CBEM has significant economic and environmental benefits. Cement and lime fillers increased cost and CO2-eq of the mixtures but it was still lower than conventional HMA.

A Sustainable Cold Mix Asphalt Mixture Comprising Paper Sludge Ash and Cement Kiln Dust

Concerns about the environment, the cost of energy, and safety mean that low-energy cold-mix asphalt materials are very interesting as a potential replacement for present-day hot mix asphalt. The main disadvantage of cold bituminous emulsion mixtures is their poor early life strength, meaning they require a long time to achieve mature strength. This research work aims to study the protentional utilization of waste and by-product materials as a filler in cold emulsion mixtures with mechanical properties comparable to those of traditional hot mix asphalt. Accordingly, cold mix asphalt was prepared to utilize paper sludge ash (PSA) and cement kiln dust (CKD) as a substitution for conventional mineral filler with percentages ranging from 0–6% and 0–4%, respectively. Test results have shown that the incorporation of such waste materials reflected a significant improvement in the mixture’s stiffness and strength evolution. The cementitious reactivity of PSA produces bonding inside the mixtures, while CKD is used as an additive to activate the hydration process of PSA. Therefore, based on the results, it will be easier to build cold mixtures by shortening the amount of time needed to reach full curing conditions.

Developing a sustainable, post treated, half warm mix asphalt for structural surface layer

Sustainability and materials recycling have increasingly acquired importance in various aspects of life. It has well known that95% of roads are paved with hot mix asphalt (HMA),theirrawmaterials require a lot of energy to prepare and lead to the releaseof a considerableamount of CO2 into the environment. As a result, developing new technologies to prepare a new sustainable asphaltic mixture that consumes less energyand is eco-friendly becomes a necessity. This research aims to develop a sustainable half-warm asphalt mix by exposing the cold bituminous emulsion mixture (CBEM) to a post treatment using microwave energy technique, as well as utilising crushed glass waste as fine aggregate. The newly developed mix (half warm bituminous emulsion mixture, or HWBEM) is evaluated in terms of two main failure distress (cracking and rutting) using wheel track (WTT) and indirect tensile tolerance index, or cracking tolerance index (CT-index), in addition to the volumetric and durability evaluation in term of air voids content (AV) and retained Marshall stability test (RMS). Tests results regarding mechanical, volumetric, and durability properties indicated that the developed mixture was relatively comparable in some of the properties with referenced CBEM and superior in one aspect. Moreover, the sustainability aspect was achieved successfully by replacing a significant amount of virgin fine aggregate with the crushed waste glass. Based on the results of the test program, it can be said that the newly developed HWBEM incorporated waste glass can work as a structural surface layer.

Evaluating Water Damage in Acrylic Polymer–Modified Cold Bituminous Emulsion Mixtures

Currently, there is a global increase in the use of sustainable technologies in the construction of pavement systems. Cold bituminous emulsion mixture (CBEM) is a promising alternative to hot mix asphalt (HMA) that offers economic, environmental, and energy-saving advantages. However, CBEMs have high water content because of the requirement for prewetting water, in addition to water within the bitumen emulsion. This additional water content causes low early strength and reduces resistance to water damage. To address this, the current study aims to evaluate the influence of water on CBEMs which have been modified with ordinary portland cement (OPC) and an acrylic (AR) polymer, evaluating them in comparison with HMAs. Marshall stability and durability, assessed by means of water damage tests, will thus be used to evaluate the influence of water content for each mix. The acrylic polymer was incorporated into the bitumen emulsion prior to the preparation of CBEMs at various percentages ranging from 0% to 5% of residual bitumen weight. The results indicate that the introduction of OPC and AR generally improves water damage resistance. The CBEM with a mix of OPC and 1.25% AR gave the best performance, showing a 12% increase in resistance compared with HMA with conventional mineral filler (CMF) and a striking 109% increase in resistance compared with CBEM with OPC only.

Characterisation of Cold Bituminous Emulsion Mixtures Using Microwave Heating Process

A previous study conducted by the authors proved that the inferiority of the mechanical properties of Cold Bituminous Emulsion Mixtures (CBEMs) could be overcome by incorporating a waste or by-product material, namely Paper Sludge Ash (PSA). The new CBEMs have demonstrated comparative mechanical and durability properties compared to conventional Hot Mix Asphalt (HMA). Furthermore, the new CBEMs have less impact on the economy, environment, and safety. However, the air void content of the new CBEMs is still high – to a stage unacceptable by pavement engineers. Thus, this study introduces a treatment method to reduce the air void without affecting the improvement achieved in mechanical properties and other environmental and economic issues. This study presents microwave energy treatment as a unique post-mix treatment method to overcome high air void content in CBEMs. Test results showed that microwave energy improves the stiffness modulus and air void content. However, new post-mix microwave treatment CBEMs still have comparative mechanical, volumetric, economic, and environmental characteristics to HMA.

Cold Asphalt Mixtures Characteristics with Cement and Sugar Industry Waste Material as Mineral Filler

Cold mix asphalt is bituminous material that produced at ambient temperatures. Many advantages can be obtained from cold mix asphalt especially, economic and environmental aspects this come from no need to heat of aggregate and bitumen for purpose the production and laying mix which are remain necessary demand to hot mix asphalt production. However, cold mix asphalt show inferior performance at early life and high porosity. This lab investigation focuses on improving the Cold Bitumen Emulsion Mixtures (CBEMs) containing 2% ordinary Portland cement (OPC) by adding Sugar industry Waste (SW) with different percentages i.e. 2, 4, 6 by total mass of aggregate. The optimum SW content was selected based on Indirect Tensile Strength (ITS) test which was 4%. ITS for the modified mix increased significantly to more than 55% and 32% in comparison with the untreated mixtures and CAEM with 2% OPC, respectively. On the other hand, the results of tests for Marshall Stability (MS), Marshall flow (MF) and index of retained strength (IRS) tests were encouraged. The value of MS and MF for mixtures with 4% SW increased about 140% and 38% respectively while, IRS improved about 45% in comparison with untreated mix. Finally, this research has gave highly improved cold bituminous emulsion mixtures (CBEMs) with SW in addition to environmental and economic benefits.

Evaluating the rutting resistance for half warm bituminous emulsion mixtures comprising ordinary portland cement and polymer

Comparison of Cold Mix Asphalt (CMA) technology to traditional Hot Mix Asphalt (HMA) technology, reveals that the first has several advantages in terms of economic, eco-friendly, safety and sustainability. A promising development of CMA technology is Cold Bituminous Emulsion Mixtures (CBEMs). Unfortunately, some characteristics of this technology are still in development need; namely high porosity, long curing time and low early strength. Half Warm Bitumen Emulsion Mixture (HWBEM) was introduced in previous attempt, as a treated CBEMs with optimum heating temperature being less than 100 °C. This work focuses on treating the CBEMs with low heat energy technique (i.e., microwave heating), plus two types of admixtures; Ordinary Portland Cement (OPC) and acrylic (AR) polymer. The effect of low energy heating (i.e., microwave heating) on developed CBEMs characteristics is tested. Acrylic (AR) polymer was utilized in percentages of 1.25, 2.5, 3.75 and 5% of the residual bitumen. The developed mixtures of HWBEM is tested statically by Marshall and dynamically by Wheel track parameters. The results reveal that the HWBEM with OPC and 1.25% AR, showed better deformation resistance roundly 81 times with vital development in its mechanical and volumetric properties comparable to traditional HMA. Therefore, low energy heating and polymer treatment sustain the new promising paving technology called HWBEM.

An evaluation of the effect of crushed waste glass on the performance of cold bituminous emulsion mixtures

Large quantities of waste glass are generated each year, as municipal solid waste, and disposed of. There are industries who could make use of this product, specifically road pavement manufacturers. The current technology for paving roads will soon become financially unsustainable because of the rapid and continuous growth of community transportation. To address this issue, this study aims to evaluate the effect of replacing local virgin aggregates with crushed waste glass has similar gradation of virgin fine aggregate with 2.36 mm Nominal Maximum Aggregate Size (NMAZ). Four replacement percentages were assessed, namely 25%, 50%, 75% and 100% from virgin fine limestone aggregates content in Cold Bituminous Emulsion Mixtures (CBEM), as CBEM technology has several environmental, sustainable and economic advantages over HMA. The test protocol involved the evaluation of the mechanical properties of CBEM’s in terms of the Marshall Test, Indirect tensile strength (ITS), wheel track test (WTT) and dynamic stability (DS) properties. Moisture damage, in respect of Retained Marshall Stability (RMS), was also evaluated for the modified mixes. The test results show that the addition of crushed glass (up to 100%) as a fine aggregate, resulted in a new CBEM with mechanical and durability properties higher than traditional HMA. While slight reductions in mechanical and durability properties were noted when compared with untreated CBEM, it was still within local specification limits of the Iraqi General Specifications for Roads and Bridges, (GSRB). In term of mechanical and durability performance, it was concluded that the new mixture (CBEM-100%FGA) can be used as a structural surface layer for heavily trafficked loading conditions. It is necessary however, to note that the new mix still has high air void contents.

Characterizing Cold Bituminous Emulsion Mixtures Comprised of Palm Leaf Ash

AbstractCold bitumen emulsion mixtures (CBEMs) are a promising substitute for hot mix asphalt (HMA) due to their low environmental impact, cost effectiveness, and low energy production costs. Never...

Performance Analysis of a Cold Asphalt Concrete Binder Course Containing High-Calcium Fly Ash Utilizing Waste Material

It has been established that cold bituminous emulsion mixtures (CBEMs) have a comparatively low initial strength in comparison to hot mix asphalt (HMA), however its superior performance with regard to carbon emissions, is a significant driver regarding its manufacture. In this research, high calcium fly ash (HCFA) together with a fluid catalytic cracking catalyst (FCC) - a rich silica-alumina waste material - have been incorporated to develop a new cold asphalt concrete binder course (CACB) bituminous emulsion mixture. HCFA was used as a substitute for traditional limestone filler while FCC was the additive used to activate the HCFA. The mixtures’ performance was assessed using the indirect tensile stiffness modulus test (ITSM), assessment of resistance against permanent deformation, temperature and water sensitivity tests. Surface morphology was tested using a scanning electron microscopy (SEM). A considerable improvement was identified by the ITSM test in addition to a substantial enhancement in rutting resistance, temperature susceptibility and water sensitivity. It was also established that the addition of FCC to CACB mixtures was found to improve early strength as well as long-term strength, rutting resistance, temperature sensitivity and durability.

New developments with cold asphalt concrete binder course mixtures containing binary blended cementitious filler (BBCF)

A weakness in early strength and the need for longer curing times in the case of cold bituminous emulsion mixtures (CBEMs) compared to hot mix asphalt have been cited as barriers to the wider utilization of these mixtures. A binary blended filler material produced from high calcium fly ash (HCFA) and a fluid catalytic cracking catalyst (FC3R) was found to be very effective in providing microstructural integrity with a novel fast-curing cold asphalt concrete for the binder course (CACB) mixture. Balanced oxide compositions within the novel filler were identified as responsible for an enhanced hydration reaction, resulting in a very high early strength and a significant improvement in permanent deformation and fatigue resistance. Improved water sensitivity for progressive hydration with the new binary filler was also established while SEM analysis confirmed the formation of hydration products after various curing ages.

Rutting Prediction of a Reinforced Cold Bituminous Emulsion Mixture Using Finite Element Modelling

A three-dimensional (3D) finite element (FE) model of a reinforced cold bituminous emulsion mixture (CBEM) was built in order to investigate the effect of static wheel load on rutting formation and flexible pavement response. This model was developed to represent a four-layer pavement structure with elastic responses and to simulate the mechanical behaviour and pavement performance under static load condition. Also, it is focused on the prediction of the contribution of glass fibre (as a reinforcement material) in the surface course to the development of the tensile and shear strength of flexible pavements. The preparation and validation of the model were carried out in the pavement laboratory using experimental data. In this research, finite element analyses have been conducted using ABAQUS software, in which model dimensions, element types and meshing strategies are employed to achieve the desired degree of accuracy and convergence of the developed model. In addition, this developed model has been applied to CBEMs to investigate the effects of glass fibre on the performance of a reinforced pavement surface layer, as well as to study the effects of this fibre in terms of minimizing the vertical surface deflection, and horizontal and vertical displacements for the various courses. Finally, the FE model is capable of predicting surface damage to flexible pavements and their partial recovery following the application of the load. The results demonstrate the capability of the model to simulate the effect of fibre on vertical surface deflection (rutting), horizontal and vertical displacements in CBEM.

Investigating Filler Characteristics in Upgrading Cold Bituminous Emulsion Mixtures

Abstract Cold Bituminous Emulsion Mixtures (CBEMs) could offer significant advantages in contrast to traditional Hot Mix Asphalt (HMA). These advantages are redaction of energy consumption, reduction of emission of pollutants, and reduction of total costs. To date, researchers have attempted, intensively, to upgrade CBEMs’ engineering characteristics to gain their whole advantages. Adding active filler materials such as Ordinary Portland Cement (OPC) develop these characteristics. In this paper, selected waste or by-product materials are investigated as alternatives to OPC. Although OPC alone or with activator has proven successful in improving curing time and mechanical properties, the successful use of waste or by-product alternatives could represent a unique environmental and economic achievement. Thus, for the first time, waste or by-product materials (PFA, PSA, GGBFS, APC, and BFA) were investigated individually and not as Supplementary Cementitious Material (SCM) for improving the curing and strength of CBEM. However, some of these filler showed significant improvement in CBEMs characteristics.

Enhancing the Mechanical Properties of Gap Graded Cold Asphalt Containing Cement Utilising By-Product Material

The little stiffness modulus, high voidage and long curing time has limited the use of CBEM's (cold bituminous emulsion mixtures) in road and highways to pavement experiencing low traffic. The aim of this study is to improve the properties of gap graded CRA (cold rolled asphalt) containing OPC (ordinary portland cement) as filler by addition of a by-product material as an activator. OPC was added to the CRA as a replacement to the conventional mineral filler (0%-100%), while LJMUA (Liverpool John Moores University Activator) was added as an additive in the range from 0%-3% by total mass of aggregate. Laboratory tests included stiffness modulus and uniaxial creep test to assess the mechanical properties. The results have shown a considerable improvement in the mechanical properties from the addition of LJMUA to the CRA containing OPC especially for the early life stiffness modulus that is the main disadvantage of the cold mixtures.

A comparative study for improving the mechanical properties of cold bituminous emulsion mixtures with cement and waste materials

This paper reports the experimental test results of a research project aimed at developing a new cold bituminous emulsion mixtures (CBEM’s) containing fly ash from incinerated domestic and industrial by-products compared with those results of traditional control cold containing OPC and hot mix asphalt.The main objectives of the experiments were to investigate the improvement in mechanical properties of CBEM’s due to incorporating OPC, and detect the possibility of replacing the OPC with waste fly ash materials. The mixtures mechanical properties investigated were; ITSM, creep stiffness. Durability in term of water sensitivity was investigated too.The results have shown comparative mechanical properties of CBEM’s to HMA. Furthermore, the new CBEM’s with fly ash used as a replacement of filler achieved outstanding results compared with traditional CBEM with and without addition of OPC. Therefore, this paper introduces a new CBEM’s having outstanding mechanical characteristics, cost effective, and environmental friendly.

Mechanical Properties of an Upgrading Cold-Mix Asphalt Using Waste Materials

AbstractConsiderable advantages could be achieved if the cold bituminous emulsion mixtures (CBEMs) show comparable engineering properties to hot-mix asphalt (HMA), particularly because CBEMs require no heat within the manufacture and laying process. As a result, such pavement produces less environmental impact, is more cost effective, and requires less energy consumption. This paper focuses on upgrading the CBEMs to a stage whereby their mechanical properties are comparable to traditional HMA. Waste or by-product materials were used within the CBEMs to improve the mechanical properties, namely indirect tensile stiffness modulus and creep stiffness. Five percentages from 0 to 5.5% of aggregate mass in the mixture of the LJMU-FA1 that is waste or by-product material was incorporated in the CBEMs. The results have illustrated a comparative enhancement in the mechanical properties of the new cold mixtures attributable to the use of the specific waste materials. Thus, new CBEMs having superior mechanical prope...

Green Bituminous Asphalt relevant for highway and airfield pavement

As no heat is required for the manufacturing and laying of Cold Bituminous Emulsion Mixtures (CBEMs), significant advantages could be gained if these mixtures have mechanical properties equivalent to those of the traditional hot mixtures. Consequently, production of Green Bituminous Asphalt relevant for highway and airfield pavement constructions creates less environmental impact. This means that the use of CBEM could achieve many advantages such as, reduction of energy consumption, emission of pollutants and total costs.The purpose of this paper is to compare the mechanical properties of traditional hot mix and modified cold bituminous emulsion mixtures incorporated with waste materials. The waste or by-product materials were used as a modifier of the CBEM’s. The comparison was made through evaluating the modification gained in the mechanical properties, namely indirect tensile stiffness modulus and creep stiffness.The LJMU-FA1 (which is a waste material) was incorporated in the CBEM’s with different dosages ranging from 0% to 5.5% of aggregate weight in the mixture. The results have shown a significant improvement in terms of the mechanical properties of the new cold mixtures due to the use of the waste materials in contrast with the properties of traditional hot mixtures.