In the European Union, more than 140 million tonnes of municipal solid waste is incinerated annually. It generates about 30–40 million tonnes of residues known as municipal solid waste incinerator bottom ash, which is typically landfilled. To deal with growing landfills, there is a need to utilize municipal solid waste incinerator bottom ash as a building material. It has been known that municipal solid waste incinerator bottom ash properties strongly depend on waste composition, which is directly influenced by people’s habits, economic policy, and technologies for metals recovery of bottom ash. Thus, municipal solid waste incinerator bottom ash produced in a specific country or region has primarily to be tested to determine its physical and mechanical properties. The main aim of this study is to determine municipal solid waste incinerator bottom ash physical and mechanical properties (aggregate particle size distribution, water content, oven-dried particle density, loose bulk density, Proctor density, optimal water content, California Bearing Ratio after and before soaking, permeability, Flakiness Index, Shape Index, percentage of crushed and broken surfaces, resistance to fragmentation (Los Angeles coefficient), water absorption and resistance to freezing and thawing). Municipal solid waste in-cinerator bottom ash produced in the waste-to-energy plant in Klaipėda (Lithuania) was used in this research. Ferrous and non-ferrous metals were separated after more than three months of municipal solid waste incinerator bottom ash ageing in the atmosphere. The study showed promising results from considering municipal solid waste incinerator bottom ash as possible aggregates for road building materials.
14 August 2020 in The Baltic Journal of Road and Bridge Engineering
The study of ancient stone pavements represents the necessary premise for planning and execution of treatments that considers the necessity of conservation. The approach to the integrated management of information derived through H-BIM has been applied to Via del Vesuvio, one of the main roads in the archaeological site of Pompeii in Naples, Italy. The digital terrain model was carried out using Autodesk Infraworks software. Then, using Autodesk Civil 3D and Revit software, the road was digitalized creating the 3D model that included road geometric information resulting from an on-site survey, material characteristics for each pavement layer, construction period and related construction cost information. Finally, based on the existing research works available in the literature review, using Autodesk Naviswork software, it was possible to implement in the 3D model the BIM fourth dimension, namely, the time related to the construction of Via Del Vesuvio in different eras. The interoperability between the adopted BIM authoring software was exploited. The adopted procedure can be considered a benchmark case in the technical literature of H-BIM for stone pavements, highlighting the advantages in the design field.
A key factor for safe and comfortable driving on roads are properly reflective and well visible pavement surfaces at night. The brightness of the road pavement surface depends on the amount of light falling on it and the reflection properties of the road pavement surface at any point. The luminance of the pavement depends on its physical condition, age and type of pavement, direction of illumination, and observation conditions. Different pavements can have different reflection characteristics that depend on the surface texture, materials, and binder (type and quantity). Experimental research was carried out on the carriageways and bicycle paths of Vilnius city streets, which differ in color and age. The analysis of the research results showed differences between the surface reflectance characteristics of these pavements depending on the color of the pavement, surface conditions, and age. The reflection properties of red asphalt pavements are better than black ones when the pavement surface is wet or moist. The reduced luminance coefficients of the carriageway (asphalt pavement installed in 2021) are about 12% lower than those of the carriageway pavement installed 10 years ago and about 60% lower for wet and moist pavements. The results obtained from the research are significant for street designers when choosing the type of pavement and designing street lighting.
26 September 2019 in The Baltic Journal of Road and Bridge Engineering
Mechanical properties and slab dimensions of concrete are the major parameters based on which the performance of concrete pavement structures is predicted. Precast concrete pavement, as one of the most common modular pavement type, is the advanced next-generation technology characterised as high quality, durable, quickly built and easily maintained. The service conditions of precast concrete pavement (traffic loading and environmental effects) are similar to the conventional cast-in-place jointed plain concrete pavement. Thus, the precast concrete pavement structural design is similar to that of jointed plain concrete pavement. There are several concepts for the design of concrete pavement structure. However, they are based on different distress evaluation and critical stresses estimation methods assuming the slab dimensions that for jointed plain concrete pavement are within the wide joint spacing range from 3.5−6.0 m. The objective of this paper is to analytically evaluate the effect of concrete mixture mechanical properties on the thickness and dimensions of precast concrete pavement slab. Also, define the minimal thickness of precast concrete slab dependent on slab dimensions and concrete mixture mechanical properties elastic modulus and tensile splitting strength. The analysis is based on bearing capacity, performance and fatigue boundary conditions as reported by semi-probabilistic pavement design method Richtlinien für die rechnerische Dimensionierung von Betondecken im Oberbau von Verkehrsflächen RDO Beton 09. Considering that, concrete mixture has significant effects on pavement performance; the composition of concrete was also discussed in this paper. The optimal slab dimensions, concrete layer thickness, and base layer type is suggested in this paper. The outcomes of this analysis apply to the production of precast concrete pavement slabs.
27 June 2019 in The Baltic Journal of Road and Bridge Engineering
Road traffic noise is a widespread problem, especially in the densely populated cities of Europe. Exposure to high levels of (traffic) noise leads to health problems, such as stress, sleep disturbance and even heart diseases. Noise-reducing asphalt pavements are more frequently developed and selected as a first noise abatement solution. Performance of noise-reducing asphalt pavement depends on the composition and properties of asphalt mixture components, and pavement properties such as layer thickness, voids in pavement, texture. Design of asphalt mixture for the noise-reducing asphalt pavements is even more complicated for severe and cold climate regions where significant temperature fluctuations and many of frost-thaw cycles occur. Thus, the balance between mechanical and acoustical durability depends on the proper selection of asphalt mixture components. Components of these asphalt mixtures have primarily to be tested to determine their physical and mechanical properties. The main aim of this research is to evaluate properties of local aggregates, bituminous binders, and regarding test results, select the most suitable materials for the design of high-quality, durable asphalt mixture for noise-reducing asphalt pavements. The research showed that Granite A is the most suitable aggregate for the design of asphalt mixtures for noise-reducing asphalt pavement. Short-term and particularly long-term ageing of polymer modified bituminous binder PMB 45/80-65 and PMB 25/55-60 decreases the number of aromatics and increases the amount of resins. Based on Multiple Stress Creep and Recovery test results, it is assumed that all bituminous binders selected for research are suitable for the asphalt mixture design of noise-reducing asphalt pavement in terms of resistance to rutting. However, considering all tests results, bituminous binder PMB 45/80-65 (1) showed the best performance and was the most suitable for the asphalt mixture design of noise-reducing asphalt pavement.
Increased traffic flow on low-volume gravel roads and deficiencies of national road infrastructure, are increasingly apparent in Lithuania. Gravel roads do not comply with requirements, resulting in low driving comfort, longer travelling time, faster vehicle amortization, and dustiness. The control of dustiness is one of the most important road maintenance activities on gravel roads. Another important issue is the assurance of required driving comfort and safety. Soft asphalt and Otta Seal technologies were proposed as a sustainable solution for the improvement of low-volume roads in Lithuania. Five gravel roads were constructed with soft asphalt, and 13 gravel roads were sealed with double Otta Seal, in 2012. The main aim of this research was to check soft asphalt and double Otta Seal’s ability to self-heal, on the basis of the results of the qualitative visual assessment of pavement defects and distress. The qualitative visual assessment was carried out twice a year following the opening of the rehabilitated road sections. The results confirmed soft asphalt and double Otta Seal’s ability to self-heal. The healing effect was more than 13% and 19% on roads with soft asphalt and double Otta Seal, respectively. In addition, on some roads, all cracks observed in spring self-healed during summer.