scholarly journals Basic Experimental Studies on Coconut Shell Charcoal Ash in Modified Bitumen

Abstract. For reducing the cost in bitumen roads and also increasing the efficiency of bituminuous roads, varieties of materials are used for improving the road by using coconut shell charcoal ash as fillers in the flexible pavement. In the literature work, the main descriptive of the work is to compare the results with different percentages of coconut shell charcoal ash in bitumen. The Properties of the coconut shell charcoal possesses are resistance to breaking the materials, absorbing the heat, moisture content of surface, grading, heating and synthetic resin glues which is important for pavement of bitumen roads. Therefore, its stability of Marshall stability test and flow value in Marshall stability and air void ratio are obtained. So that it can be compared with different modified percentage as 4.5%, 5%, 5.5% and 6% in test on Bitumen. From this test we can establish so that it can be useful as a substitute as a coconut shell charcoal ash for improving the strength, quality and durability of bitumnious road. For carrying out these experiments, Marshall stability test is used for obtaining better results for normal mix and modified mix for the bitumen.

During the maintenance or the construction of asphalt pavement the utilization of reclaimed asphalt pavement (RAP) can diminish the cost of the project, time consumption, conservation of natural resources and most importantly no harm to the environment. In this paper we are going to study the performance of pavement containing RAP (20%, 30%, 40% and 50% excluding the RAP aggregates of size 20 mm), anti-stripping agent Zycotherm, 1% of virgin bitumen contain are replaced by bitumen attached on RAP aggregates after the screening process. Tests performed for conventional and modified pavement sample are Marshall Stability and flow. Test for virgin aggregates and RAP aggregates are impact test, crushing test, shape test, specific gravity and bitumen extraction test. Test for virgin bitumen and modified bitumen are softening and penetration test.


Coatings ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 54
Author(s):  
Nicola Baldo ◽  
Matteo Miani ◽  
Fabio Rondinella ◽  
Jan Valentin ◽  
Pavla Vackcová ◽  
...  

This paper presents a study about a Machine Learning approach for modeling the stiffness of different high-modulus asphalt concretes (HMAC) prepared in the laboratory with harder paving grades or polymer-modified bitumen which were designed with or without reclaimed asphalt (RA) content. Notably, the mixtures considered in this study are not part of purposeful experimentation in support of modeling, but practical solutions developed in actual mix design processes. Since Machine Learning models require a careful definition of the network hyperparameters, a Bayesian optimization process was used to identify the neural topology, as well as the transfer function, optimal for the type of modeling needed. By employing different performance metrics, it was possible to compare the optimal models obtained by diversifying the type of inputs. Using variables related to the mix composition, namely bitumen content, air voids, maximum and average bulk density, along with a categorical variable that distinguishes the bitumen type and RAP percentages, successful predictions of the Stiffness have been obtained, with a determination coefficient (R2) value equal to 0.9909. Nevertheless, the use of additional input, namely the Marshall stability or quotient, allows the Stiffness prediction to be further improved, with R2 values equal to 0.9938 or 0.9922, respectively. However, the cost and time involved in the Marshall test may not justify such a slight prediction improvement.


Improvement in transportation system is never been as easy as just providing links for better connection and network but more to do with the pavement quality of the road itself. Modification with agriculture waste is just another approach to enhance the performance of asphaltic concrete. In this study, a non-traditional bitumen modifier from a coconut shell which is the charcoal coconut shell ash (CCSA) was used. Addition of CCSA in bitumen with 0%, 2%, 4%, 6%, and 8% by weight of bitumen were investigated along with the laboratory stimulation of aging was applied in this study. Properties of modified asphalt mixture were determined using resilient modulus, dynamic creep and Marshall Stability test.. Results of samples with CCSA which underwent aging show some improvement in terms of the stability and permanent deformation characteristics. Resilient modulus, dynamic creep and Marshall Stability tests recorded the highest rates when compared to controlled sample. Hence, for more durable asphalt concrete and high serviceability it is recommended to use 2% to 4% of CCSA.


The main objective of this study was to investigate the effect of SBS polymer and warm mix additive on the performance of bituminous concrete mixes. SBS polymer dosage was kept 3%, 5% and 7% and Zycotherm additive dosage was kept 0.1% for all binder mixes. Comparisons were made between Base bitumen, SBS modified bitumen and Zycotherm modified bitumen. For preparation of bituminous mixes, two different types of aggregates were used in this study i.e. Limestone and riverbed aggregate. To evaluate the performance of modified binder; Marshall Stability test, Indirect Tensile Strength (ITS) test and Rheological test were performed on binders and bituminous concrete mixes. From Marshall Stability test, SBS dosage of 5% was found to be optimum polymer content for both aggregate mixes. Maximum tensile strength for both the aggregate bituminous mixes was achieved at 5% SBS content. It was observed that maximum Marshall Stability was achieved when Limestone aggregates were used for preparation of bituminous mixes. Zycotherm additive does not have any significant effect on the properties of bituminous concrete mixes. However Zycotherm additive tends to decrease viscosity of binder at a temperature above 100 ˚C which will result in lower mixing temperature without compromising the performance of bituminous binder. Rheological test on different binders has shown that Zycotherm additive has very less affect on rutting resistance of modified bitumen. It was finally concluded that best results were obtained from Limestone aggregates using 5% of SBS polymer and Zycotherm additive has no significant effect on mechanical properties of mix


Author(s):  
Anna Trautvain ◽  
Andrey Akimov ◽  
V. Chernogil'

the specificity of the construction of roads is the use of a huge amount of various stone materials - sand, gravel, etc. To reduce the cost of road pavements, it is possible to replace stone materials with local soils. Such materials do not need to be transported by road or rail. It is known that most soils cannot be used in the construction of the road bed (sandy loam and loam are light dusty and heavy dusty, clay dusty and oily), as their use leads to the appearance of various deformations of the upper layers of road pavement. This problem can be solved by strengthening the soil with various types of binders, in particular, clinker waste. When conducting experimental studies to assess the effectiveness of the use of waste clinker production to strengthen the soil the following compositions without using: soil and 9% waste; soil and 18% waste; soil and 27% waste were investigated. As a result of the research, the main dependences of the changes in the physical and mechanical parameters of the soil concrete on the amount of waste clinker production introduced into the composition of various types of soils were identified. It was found that the use of waste clinker production to strengthen the loam allowed to obtain a reinforced soil brand M20. Strengthening sand with clinker production without the addition of cement is not practical, as the samples do not gain even minimal strength for 180 days, which allows them to be classified by brand, in addition, such samples have extremely low resistance.


2021 ◽  
Vol 13 (6) ◽  
pp. 3315
Author(s):  
Mansour Fakhri ◽  
Danial Arzjani ◽  
Pooyan Ayar ◽  
Maede Mottaghi ◽  
Nima Arzjani

The use of waste materials has been increasingly conceived as a sustainable alternative to conventional materials in the road construction industry, as concerns have arisen from the uncontrolled exploitation of natural resources in recent years. Re-refined acidic sludge (RAS) obtained from a waste material—acidic sludge—is an alternative source for bitumen. This study’s primary purpose is to evaluate the resistance of warm mix asphalt (WMA) mixtures containing RAS and a polymeric additive against moisture damage and rutting. The modified bitumen studied in this research is a mixture of virgin bitumen 60/70, RAS (10, 20, and 30%), and amorphous poly alpha olefin (APAO) polymer. To this end, Marshall test, moisture susceptibility tests (i.e., tensile strength ratio (TSR), residual Marshall, and Texas boiling water), resilient modulus, and rutting assessment tests (i.e., dynamic creep, Marshall quotient, and Kim) were carried out. The results showed superior values for modified mixtures compared to the control mix considering the Marshall test. Moreover, the probability of a reduction in mixes’ moisture damage was proved by moisture sensitivity tests. The results showed that modified mixtures could improve asphalt mixtures’ permanent deformation resistance and its resilience modulus. Asphalt mixtures containing 20% RAS (substitute for bitumen) showed a better performance in all the experiments among the samples tested.


2000 ◽  
Vol 1712 (1) ◽  
pp. 196-201 ◽  
Author(s):  
Jin-Fang Shr ◽  
Benjamin P. Thompson ◽  
Jeffrey S. Russell ◽  
Bin Ran ◽  
H. Ping Tserng

An increasing number of state highway agencies (SHAs) are using A (cost) + B (time cost) bidding ( A + B bidding) for highway construction. The A + B bidding concept is designed to shorten the total contract time by allowing each contractor to bid the number of days in which the work can be accomplished, in addition to the traditional cost bid. The SHA is then presented with the problem of determining a reasonable range of contract time submitted by the bidders. Most SHAs do not currently restrict the range of B. However, several problems may arise from an unrestricted range of B. First, if no minimum is set for B, a bidder may inflate the cost bid and submit an unreasonably low B, using the excess cost bid to cover the disincentives charged for exceeding the time bid. Second, if no maximum is set for B, then a bidder with a high B and a low-cost bid may be awarded the job and make an unreasonable amount of money from incentive payments. This study develops a quantified model of the price-time bidding contract. A construction cost-versus-time curve is developed from Florida Department of Transportation (DOT) data. The contractor’s price-versus-time curve is then combined with the road-user cost to determine the optimum lower limit to be set on B. Finally, several projects completed by the Florida DOT will be used to illustrate this model.


2021 ◽  
Vol 1038 ◽  
pp. 336-344
Author(s):  
Olena Pinchevska ◽  
Andriy Spirochkin ◽  
Denys Zavialov ◽  
Rostislav Oliynyk

The reasons of white spots appearance in the middle of oak timber are determined. These white spots reduce the cost of the lamina made of oak timbers - the front covering of floorboards. It is proposed to intensify the drying process by using oscillating drying schedules to avoid this defect. A method for calculating the duration of such drying is proposed. This method includes the peculiarities of heating and cooling periods kinetics of oak timbers with 25 mm and 30 mm thickness. The inexpediency of using the oscillation of the drying agent parameters in the range of wood moisture content below 20% has been established. An adequate model for calculating wood temperature and air humidity during wood heating and cooling periods has been developed using heat and mass transfer criteria and experimentally determined oak wood moisture conductivity coefficient. Based on the results of theoretical and experimental studies oscillating drying schedules of different thickness oak timbers are offered. Tests of the proposed schedules in industrial conditions showed no discoloration of the central layers of European oak (Quercus robur) timbers. The drying process duration was reduced by 1.5–2.4 times and energy consumption were reduced by 1.53 times.


2021 ◽  
Vol 2021 (23) ◽  
pp. 20-30
Author(s):  
Taras Pechonchyk ◽  
◽  
Vitaliy Ivanchenko ◽  

AbstractIntroduction. Effective management of road indstry is particularly important in conditions of limited funding, as it is not possible to provide adequate funding of the economic entity that has the functions of a customer service. The cost of the customer service maintenance depends directly on the compliance with applicable regulations for these works cost determination. One of the aspects that form a considerable part of the costs of customer service is the maintenance of service vehicles.Problem Statement. Road services in the regions (hereinafter RSR) are the recipients and managers of the funds from the State Budget of Ukraine that are directed for the development and maintenance of public roads of state importance, being as well the asset holders of these roads. To perform their functions, the RSR have vehicles on their balance, the use of which involves a number of costs, including fuel and lubricants, repair, maintenance, replacement of tires, etc. The most important of the steps involved in setting the costs of vehicle maintenance is the process of cost planning. Planning has to be based on the structure of the vehicle fleet (own or leased), functional responsibilities and scope of road works.Planning is carried out for vehicles on the balance of the RSR, as well as for leased vehicles. In the case of leasing, the costs mentioned above are added by the vehicles leasing costs. These costs must be forecasted, justified and performed within the approved cost estimates of the customer service expenses.Purpose. The purpose of the article is to highlight the theoretical and methodological approaches to the calculation of planned costs for the maintenance of service vehicles of the road works customer.Materials and methods. Dialectical methods of knowledge, such as analysis and synthesis of fleet composition characteristics and approaches to cost planning methods, as well as induction, were used in writing the article to explore some aspects of the process of calculating the planned cost of maintenance of the road works customer's service vehicles.Results. The study highlights and describes the main approaches to the calculation of planned costs for the maintenance of service vehicles of the road works customer. The methodology of calculation of planned costs for the maintenance of service vehicles is explored.Conclusions. The introduction of a clear methodology and analytical toolkit for calculating all necessary expenditure items for the maintenance of the road works customer's vehicles in the cost planning process will establish the implementation of a clear mechanism for calculating the planned costs of maintenance of the road works customer's vehicles. It will also provide an automated information-analytical complex for planning of cost estimates, with information entry and reporting in standard forms and possibility of prompt response to changes in fleet composition, needs for spare parts, repairs or other expenses for the maintenance of service vehicles and making changes in cost estimates.Keywords: motor vehicles, costs, cost planning, customer service, maintenance of service vehicles


2021 ◽  
Vol 2021 (23) ◽  
pp. 31-42
Author(s):  
Anatolii Tsynka ◽  
◽  
Andrii Hrinchuk ◽  
Ivan Rakovych ◽  
◽  
...  

Introduction. In the modern conditions of the pricing system in the construction of Ukraine, the key value have the estimated norms, which are presented in separate collections, the main purpose of which is to determine the standard quantity of resources required to perform a particular type of work as a basis for the transition to the cost indicators. In order to determine the cost of road work objectively and accurately, it is essential that the indicators of estimated norms meet the requirements of regulatory documents and modern methods of execution of road works.Problematics. In connection with the active improvement of the regulatory base of the road construction industry, permanent upgrade of road organizations technique fleet, the introduction of new technologies and materials in construction and operation of roads, improving the methods of work there is a discrepancy between the existing resource element of estimated norms and the actual conditions of work in terms of built-up labor costs, the operation time of machines and mechanisms and the range of materials. Accordingly, it affects the reliability and accuracy of determining the cost of road works.Purpose. Improvement and harmonization with actual working conditions and requirements of regulatory documents of industry regulatory and estimate base of resource elementary estimated norms for work performed during construction, reconstruction, repair and operational maintenance of roads and bridges to ensure reliable and valid technical, economic and estimated calculations.Materials and methods. During work performance the analysis of the regulatory documentation, establishing the requirements to the technology of road works and materials has been carried out. A number of chronometric observations with the measurement of time of road works in full-scale conditions was carried out. The obtained data were summarized, averaged and on their basis the indicators of the resource element of the estimated norms were estimated.Results. A review of the main amendments and additions, which came into force after the approval of Amendment No 2 SOU 42.1-37641918-035:2018 [1] and Amendment No 2 SOU 42.1-37641918-071:2018 [2], which were developed to improve the regulatory-estimate base for the calculation of road works, taking into account the requirements and provisions of existing regulatory documents taking into account the current state of scientific and technological progress in the road sector.Conclusions. The above analysis of the amendments that came into force with the approval of [1]. and [2] will systematize the innovations provided by the requirements of current regulatory documents on the calculation of the cost of road works and the development of relevant documents at all stages of the investment process, planning and organization of road works, as well as the writing-off of material resources. Review and systematization of recent improvements in the estimated regulatory documents for road works will provide an opportunity to optimally plan the use of available material, labor and financial resources, often limited.Keywords: public road, operational maintenance, investment documentation, overhaul and current repairs, machine, mechanism, regulatory document, resource element estimate norm, Standard of Organization of Ukraine.


Sign in / Sign up

Export Citation Format

Share Document