Hasil untuk "Highway engineering. Roads and pavements"

Filippo Giammaria Praticò, Gianfranco Pellicano

Knowledge of the dynamic modulus of bituminous mixtures is practical and theoretically meaningful in pavement design, construction, and monitoring. The tests in the laboratory for the determination of asphalt concrete (AC) moduli include the resilient modulus through the indirect tensile test (EN 12697-26), the complex modulus through the four point bending beam (EN 12697-26), the asphalt mixture performance tester (AMPT) and the simple performance tester (SPT) (AASHTO T342). Unfortunately, the tests above are time-consuming and quite expensive. On the other hand, the standard ASTM E1876 for resonant tests applies only to very thin (stocky) cylindrical samples (with a thickness-to-radius ratio, t/r, lower than 0.5) while the typical AC samples produced in the laboratory do not satisfy the ASTM E1876 requirements. Consequently, the main objective of this study is to set up and implement a tentative method to extend the range of applicability of the standard ASTM E1876 to common AC samples. The methodology was to carry out resonant tests on slender samples and to cut each of them into stocky samples (these latter complying with ASTM E1876 requirements in terms of t/r), deriving the master curve per material. These master curves allowed for deriving the value of the dynamic modulus for the given selected sample under its particular test conditions during the resonant test (i.e., temperature and frequency). Consequently, simplified formulae were provided for AC samples. Results were compared to Witczak's estimates. These formulae provide an approximate tool to carry out low-cost and high-speed inferences at the laboratory stage on common AC samples, whatever their thickness is. Additional studies are needed to investigate the reliability of the method further and reduce uncertainties.

Andrzej Ambroziak, Maciej Malinowski

A 120-year-old railway truss bridge over the Bóbr River, Poland, is investigated in this paper from the mechanical and chemical properties of the materials by testing of old steel samples in a lab – through geodetic measurements, bathymetric measurements of the riverbed and dynamic measurements of bridge spans under service load – to the analysis of structural behaviour by finite-element modelling. The mechanical and chemical properties of the structural old steel are investigated by testing steel elements extracted from the old bridge. Structural analysis shows that the bridge is eligible for renovation or replacement for a new one due to unfulfilled today’s load requirements in terms of bearing capacity. The paper begins with a survey of chosen literature carried out on the investigation of the old steel railway bridge's subject matter. This paper can provide scientists, engineers, and designers with an experimental and structural basis in the field of old steel riveted railway truss bridges.

Serhii Illiash, Volodymyr Kaskiv, Yuliya Bibyk

Introduction. As a result of a large-scale armed attack on the sovereign territory of Ukraine and active hostilities, most of the military, civilian and infrastructure facilities have been significantly destroyed or damaged. In such circumstances, it is important to have methodological approaches to determining the amount of damage caused by hostilities and further economic assessment of the damage. Problem Statement. Consideration of this topic is the need to clearly define methodological approaches to determining the amount of damage and losses caused to roads as a result of active hostilities. Purpose. To formulate methodological approaches to determining the amount of damage caused by hostilities and further economic assessment of the damage caused. The accuracy and validity of the methodological approach determines the admissibility of the reliability of the calculation and determination of the amount of funds. To accomplish this task, it is necessary to establish definitions of the concepts of "damage" and "losses", since these are different concepts and should be clearly understood by all professionals who will assess the amount of damage. Materials and methods. The article uses a systematic approach, which is a set of general scientific methodological principles (requirements) based on the consideration of objects as systems. The priority of this process is to ensure an adequate level of data objectivity, timeliness and relevance of the processed information.

Nataliia Shliun, Valerii Gulyayev

Introduction. Thermomechanical effects arising in heterogeneous composite materials under the influence of temperature significantly affect the strength and durability of structures made of them. These effects have a special influence on the thermal deformation of bridge and road structures under conditions of seasonal and daily changes in ambient temperature. They are caused by non-uniformity of the thermomechanical parameters of its fractions and fittings. Until now, the phenomenon of thermomechanical deformation of reinforced structures has not been sufficiently studied, therefore the tasks of their research are urgent. Problem Statement. The problem of the performed research is to establish the laws of thermomechanical deformation of composite materials (including cement concrete and asphalt concrete), which are reinforced with reinforcing rods, in the fields of variable temperatures. Purpose. The purpose of the work is to derive mathematical ratios that determine intrastructural thermal stresses in composites caused by variable temperature fields and heterogeneity of materials.

Chaohui Wang, Shuai Huang, Qian Chen et al.

With the rapid development of asphalt pavement technology, it has attracted considerable attention to improving the durability of asphalt pavement. An effective action is to use modified asphalt with high performance and durability. Polyurethane (PU) has been used in asphalt pavement engineering to enhance the durability and service life of asphalt pavement because of its excellent high-temperature performance, toughness, wear resistance, aging resistance and oil resistance. However, PU modified asphalt technology is still in the exploratory stage. The preparation, modification mechanism and working performances of PU modified asphalt need to be further clarified. Therefore, this paper summarized the research progress of PU modified asphalt and its mixture. The composition of PU modified asphalt was introduced. The addition methods of PU materials and preparation process parameters of the PU modified asphalt were determined. The modification mechanism of PU on asphalt was discussed. The effects of polyurethane on asphalt were analyzed and the road performances of its mixture were evaluated. Finally, the development tendency towards PU modified asphalt and its mixture were forecasted.

Monika Natalia, Jajang Atmaja, Mafriyal et al.

Pemilihan metode penyambungan tulangan untuk perkuatan struktur kolom merupakan suatu keputusan yang penting karena mempengaruhi biaya, waktu dan kualitas konstruksi. Ada beberapa macam metode yang telah berkembang dari metode konvensional diantaranya metode coupler dan welding. Metode coupler adalah penyambungan mechanical splice yang menyambungkan kedua ujung tulangan dengan pembuatan ulir atau pengepresan ujung tulangan, sedangkan welding adalah proses menyatukan dua logam atau lebih menjadi bentuk sambungan menggunakan proses panas, pencairan dengan elekroda atau filler. Penelitian ini dilakukan pada Proyek Revitalisasi Pusat Kesenian Jakarta Taman Ismail Marzuki. Proyek ini memiliki permasalahan pada metode penyambungan tulangan kolom pada basement 1 ke lantai 1 karena adanya strutting dinding penahan tanah. Jadi dibutuhkan metode tambahan untuk penyambungan tulangan kolomnya. Metode yang digunakan pada pelaksanaan proyek adalah metode coupler, pada penelitian ini akan dihitung berapa biaya dan waktu jika digunakan metode welding. Tujuan penelitian ini adalah menghitung biaya dan waktu dengan penerapan metode coupler dan welding pada Proyek Revitalisasi Pusat Kesenian Jakarta Taman Ismail Marzuki. Dari hasil penelitian, didapatkan bahwa biaya pekerjaan kolom dengan metode coupler sebesar Rp. 2.496.157.849,00 dengan waktu pelaksanaan 81 hari. Sedangkan biaya metode welding sebesar Rp. 2.529.332.648,00 dengan waktu 83 hari. Penerapan metode coupler 3,8 % lebih murah dan 2 hari lebih cepat dibandingkan dengan metode welding.

Sulwan Permana, Ari Asmedi Candra

Pembangkit Listrik Tenaga Minihidro (PLTM) Cisanggiri adalah pembangkit listrik yang terletak di Kecamatan Cihurip Kabupaten Garut Jawa Barat. Pembangkit Listrik Tenaga Minihidro ini merupakan energi potensial yang berasal dari air kemudian diubah menjadi energi listrik dengan daya 100 Kv sampai dengan 10 MegaWatt. Sungai Cisanggiri ini dalam pemanfaatannya memiliki beda tinggi head elevasi kontur tanah ± 114 m sehingga layak digunakan untuk membangun pembangkit listrik. Hal ini terbukti dengan dibangunnya PLTM Cisanggiri yang memiliki kapasitas daya listrik 1.5x2 MegaWatt, namun kapasitas keluaran daya listrik ini belum maksimal, sehingga PLTM Cisanggiri ini perlu di evaluasi kembali untuk mengetahui keluaran daya listrik maksimalnya. Evaluasi perhitungan ini dilakukan berdasarkan layout design existing yang telah dibangun sebelumnya serta data klimatologi yang terdapat di area sekitar DAS Cisanggiri. Kemudian dievaluasi untuk mengetahui apakah permasalahan yang membuat PLTM Cisanggiri ini tidak maksimal. Debit yang dihitung merupakan debit andalan atau debit ketersediaan yang dihitung berdasarkan metode FJ Mock dengan probabilitas Q85% menggunakan data hujan 10 tahun. Kemudian perhitungan selanjutnya mencari kehilangan energi (headlosses) pada sistem bangunan PLTM Cisanggiri dan daya listrik yang dihasilkan. Hasil dari perhitungan didapat debit ketersediaan pada sungai Cisanggiri sebesar 7.82 m³/s, dengan kehilangan energi (headlosses) yang telah dihitung berdasarkan kehilangan energi pada gesekan penampang saluran, headrace, pembesaran dan pengecilan penampang, trashrack dan penstock sebesar 1.45452 m. Kemudian setelah itu dievaluasi perhitungan daya keluaran listrik maksimal yang dapat dihasilkan PLTM Cisanggiri ini yakni sebesar 5.7 MegaWatt.

Dhita Agustin, Ketut Aswatama Wiswamitra, Dwi Nurtanto

Material styrofoam dapat digunakan sebagai alternatif untuk mengurangi beban mati pada struktur bangunan. Selain itu, penggunaan beton geopolymer dapat digunakan sebagai solusi untuk mengurangi penggunaan semen yang tidak ramah lingkungan karena proses produksi semen menghasilkan gas CO2. Penelitian ini dilakukan untuk mengetahui bagaimana sifat mekanik beton ringan menggunakan geopolymer dengan styrofoam sebagai substitusi agregat kasar. Diameter yang digunakan pada penelitian yaitu 1-2 mm dan 3-5 mm, kemudian persentase styrofoam yang digunakan yaitu 25%, 50%, 75%, dan 100%. Pengujian sifat mekanik beton teridi dari pengujian kuat tekan umur 28 hari dan kuat tarik belah umur 28 hari. Hasil yang diperoleh adalah berdasarkan perbandingan diameter styrofoam 1-2 mm memiliki kuat tekan dan kuat tarik belah lebih tinggi daripada diameter styrofoam 3-5 mm. Selain itu, kuat tekan dan kuat tarik belah mengalami penurunan seiring bertambahnya persentase styrofoam. Persentase yang sesuai dengan standar beton ringan struktural adalah 75% untuk diameter 1-2 mm dimana diperoleh kuat tekan dan kuat tarik belah berturut-turut 21,16 MPa dan 6,357 MPa. Selain itu, untuk diameter 3-5 diperoleh kuat tekan dan kuat tarik belah berturut-turut 21,72 MPa dan 4,124 MPa.

Randhi Saily, Ulfa Jusi

Daerah irigasi Bunga Raya mengairi area pertanian dan persawahan di kecamatan Bunga Raya dengan total panjang saluran 10,19 kilometer. Pada tahun 2019 lahan sawit dikembalikan menjadi lahan pertanian seluas 200 hektar sehingga perlu diketahui perubahan kebutuhan air akibat perubahan tata guna lahan dan dimensi saluran yang efisien untuk memenuhi dan mencukupi kebutuhan air di daerah irigasi Bunga Raya. Analisa yang digunakan adalah analisa hidrologi dengan distribusi frekuensi metode log person III. Perhitungan alternatif pola tanam padi-padi-palawija dimulai periode September mendeskripsikan bahwa kebutuhan air terbesar terjadi pada Periode II bulan Februari sebesar 1,705 ltr/dt/Ha dengan luas sawah yang bertambah semula 200 Ha maka debit aliran rencana saluran primer sebesar 2,788 m3/dtk. Dimensi ekonomis saluran primer daerah irigasi Bunga Raya dengan bentuk trapezium adalah lebar atas permukaan (Ts) = 10,015 m , lebar permukaan air (Ta) = 9,765 m, lebar dasar (b) = 7,397 m, tinggi (y) = 4,739 m dan tinggi jagaan 0,50 m

Teresė Leonavičienė, Saugirdas Pukalskas, Vidmantas Pumputis et al.

The purpose of this paper is to analyse the possibility for predicting the outcome of a road traffic accident concerning the traffic environment, personal traits of the traffic participant and the vehicle, i.e. aiming to answer the question whether specific values of the factors analysed to increase the likelihood of a fatal accident. The logistic regression model that allows identifying the relationship between the dependent and independent variables were used in the research. Other methods for describing and analysing categorical variables were also used alongside the logistic regression. When analysing the results, it was recognised that the odds ratio above 1 shows a higher likelihood for a representative of the category in question to be involved in a fatal accident compared to a representative of the base category. Odds ratios of likelihoods for calculation of the road traffic accident types show that the likelihood of a fatal accident is statistically significant affected by rollovers or driving into obstacles, compared to vehicular collisions. When summarising the results, it was stated that most of the factors researched have an impact on the outcome of a road traffic accident. The influence of some factors has a higher probability of resulting in a fatal accident as compared to other factors.

Paola Di Mascio, Laura Moretti, Americo Capannolo

Mustafa Nur Istanbuly, Bahman Jabbarian Amiri, Amir Hossein Hamidian

There are different pollution sources, which affect soil including transportation, especially in highways. These effects can be assessed by Environmental Impact Assessment. In this study, seven sampling stations were selected in different distances (0, 10, 20, 50, 100 meter) along Tehran- Karaj highway. Samples were collected and their concentrations of Pb were measured using a FAAS after dry acid digestion. It was observed that the highway had a negative impact on the peripheral soil. These impacts were higher in Tehran with average lead concentrations, and declined by moving toward Karaj. Moreover, the average concentration of lead in soil significantly decreased by increasing distance from the roadside.
 Highest lead concentration was in station (E) in the middle of the road with an average of 160.50 mg/kg. The highest average concentrations were observed in soils of the roadside with an average of 115.25 mg/kg. The highest concentration was also observed in station (B) and in the roadside, with a concentration of 302 mg/kg, which was above the international allowable limits. Tehran- Karaj highway is in the list of the most polluted roads in the world and it must be concerned for its lead pollution, especially in the roadside. Essential steps for controlling the negative impacts must be taken including the expansion of green-space along the highway.

Ali Ghorbani, Maysam Salimzadehshooiili, Jurgis Medzvieckas et al.

In this paper, stress-strain behaviour of sand-clay mixture stabilised with different cement and rice husk ash percentages, and reinforced with different polypropylene fibre lengths are evaluated. Mixtures are widely used in road construction for soil stabilisation. It is observed that replacing half of the cement percentage (in high cement contents) with rice husk ash will result in a higher unconfined compressive strength. In addition, the presence of 6 mm polypropylene fibres will help to increase the unconfined compressive strength of stabilised samples, while larger fibres cause reverse behaviour. In addition, introducing a new index for assessing the effect of curing days. Curing Improvement Index it is obtained that larger fibres show higher Curing Improvement Index values. Results gained for the effects of curing days, and fibre lengths are further discussed and interpreted using Scanning Electron Microscopy photos. Based on the conducted Unconfined Compressive Strength, Indirect Tensile Strength, and Flexural Strength tests and using evolutionary polynomial regression modelling, some simple relations for prediction of unconfined compressive strength, indirect tensile strength, and flexural strength of cement-rice husk ash stabilised, and fibre reinforced samples are presented. High coefficients of determination of developed equations with experimental data show the accuracy of proposed relationships. Moreover, using a sensitivity analysis based on Cosine Amplitude Method, cement percentage and the length of polypropylene fibres used to reinforce the stabilised samples are respectively reported as the most and the least effective parameters on the unconfined compressive strength of specimens.

Rajan Choudhary, Dibyatonu Chattopadhyay, Abhinay Kumar et al.

For a fast developing economy like India, expansion, rehabilitation, and maintenance of transportation infrastructure is crucial and require huge quantities of high quality natural aggregates. Meanwhile, vast amounts of industrial wastes accumulating in the country pose problems related to safe and sustainable disposal. The present study investigated possible utilisation of marble dust, a waste from stone industry, and fly ash, a waste from thermal power stations, as filler materials in open-graded friction course mixes. Open-graded friction course mixes incorporating fly ash, marble dust, and two sources of stone dust as filler fractions were designed and evaluated for mix design properties including draindown, abrasion loss, air void content, and permeability. Morphology of each filler was characterised through scanning electron microscopy. Physicochemical properties of fillers were examined through Rigden voids, German filler test, methylene blue, and hydrometer analysis. Analysis of variance using Fisher multiple comparison procedure was performed to evaluate the effect of filler type on design properties of open-graded friction course mixes. Regression analysis using forward selection technique was performed to identify significant filler characteristics influencing open-graded friction course properties. Results showed that filler type affected open-graded friction course design parameters significantly. Open-graded friction course mixes with marble dust showed promising performance with lowest draindown, and highest durability, air voids, and permeability. Regression analysis identified Rigden void content of filler materials as a major filler characteristic affecting the mix design parameters of open-graded friction course mixes.

Takaaki Kawanaka, Masanobu Matsumaru, Shuichi Rokugawa et al.

Developed countries like Germany and Japan, and many of their municipalities currently have large debts that will likely increase over time. These debts may never be repaid because debt repayment per capita will increase as a result of decreasing populations. It has become difficult for them to maintain many of their existing bridges because of large debts. Given the challenges faced with maintaining these bridges, it is necessary to formulate plans that may include discontinuing the maintenance on certain bridges. Therefore, this study proposes the use of a triage methodology for managing bridges (e.g., highway bridges) much like the triage methodology used by medical institutions to handle large numbers of patients after a severe disaster. More specifically, the proposed methodology makes decisions based on whether or not to build a new bridge after an existing bridge has reached the end of its lifespan and is decommissioned by evaluating factors such as cost and convenience. This is done by establishing a virtual network comprising of links made up of bridges that span across towns. This study proposes models and simulates this social problem by virtual networks and virtual bridge data, which can then be used to derive an optimal solution.

Hendri Rahmat, Fadrizal Lubis

Pada dari tahun 2011 – 2015 terjadi 21 perkara kecelakaan lalulintas dengan korban meninggal dunia sebanyak 14 orang, luka 568.770,000 (sumber : Polres Pelalawan). Banyak faktor yang menyebabkan terjadinya kecelakaan salah satunya  faktor geometrik jalan. Hasil yang diperoleh alinyemen horizontal pada tikungan terjadi perbedaan antara as jalan existing dengan as jalan hasil perhitungan yang mengacu ke standar Bina Marga. Dari hasil perhitungan superelevasi terlihat bahwa superelevasi existing di tikungan tidak sesuai dengan standar Bina Marga. Maka dapat disimpulkan bahwa geometrik jalan merupakan faktor penyebab terjadinya kecelakaan di tikungan STA 40+100 ruas jalan Simpang Lago – Sekijang Mati

Ali Ghorbani, Hadi Hasanzadehshooiili, Antanas Šapalas et al.

Designing a suitable, applicable and efficient support system for underground road structures have always been one of the most important engineering tasks for tunnel engineers. There are some different support systems applied to making underground structures safe against overburden and lateral pressures. Among these systems, permanent or temporary steel frames, wire meshes, rock bolts and shotcretes have been commonly used for suffering the exerted burdens and making the structure a safe place. This paper proposes a numerical analysis of the geometrical instability of steel-arch shells as one of the main bodies of underground road structure liners by means of calculating their buckling load and utilizing the finite element method. In this regard, a considerable number of structures (84) having different geometrical parameters have been modelled and their buckling loads have been calculated. For this purpose, the thickness, internal angle and radius of the periphery cylinder of the arch-shell system were considered taking into account geometrical parameters. Moreover, to accurately model the buckling load using the proposed algorithm, the weight of the structure has also been included in the made calculations. Finally, as the main scope is based on the Cosine Amplitude Method, sensitivity analysis is carried out to investigate the strength of the relationship between each input geometrical parameter and their buckling load. Based on the obtained relationships, the thickness of the structure is reported as the most affective geometrical parameter on buckling steel arch-shell support systems. In addition, the internal angle of arch supports is the least influential parameter.

Donatas Čygas, Darjušas Mučinis, Henrikas Sivilevičius et al.

Due to destructive factors (traffic loads, climatic and weather conditions, improper exploitation materials), bitumen properties irreversibly change in unservicable asphalt concrete. Due to irreversible processes of oxidation the aged bitumen stiffens, its physiochemical properties, ductility, adhesion and cohesion as well as sectional composition (relative amounts of asphaltenes, oils and resins) change. Bitumen in the reclaimed asphalt pavement (RAP) may be restored to properties approximate to those of the virgin bitumen by adding the following rejuvenators: softening or rejuvenating agents as well as soft bitumen. The article presents the experimental data on RAP obtained from laboratory tests conducted with Marshall specimens without additives when RAP was supplemented by different types of virgin road bitumen, the paving grade of which was 50/70, 70/100, 100/150, 160/220, respectively. The content of newly added binder of all types to RAP was 0.5%, 1.0%, 1.5%, 2.0%, and 50/70 in addition and 4.0% and 6.0% of RAP mass. The total bitumen content increased by the same percentage amount in the reclaimed asphalt, which was not always optimal. Marshall specimens were formed with these bitumen contents, the tests of which enabled to identify stability (S), flow (F), Marshall quotient (S/F), air voids content (Vm), bulk density (SDD – ρb SD) of asphalt concrete samples and the maximum density of asphalt. Having extracted all RAP and reclaimed asphalt samples according to the differential method, the factual content of soluble binder in them and its penetration, softening point, Fraass breaking point, ductility and penetration index Ip were calculated. The dependences of the reclaimed asphalt physical and mechanical parameters on the virgin rejuvenating bitumen grade and its added percentage amount were obtained. Data analysis and their generalization was conducted.

Manuel Moya, Eutiquio Gallego, Ana Isabel García et al.

Low-volume roads play an essential role in the development of rural areas in Spain, yet most are in a poor condition since hardly any money is designated for their upkeep. This work proposes a management system for the Spanish low-volume road system based on an analysis of the present management of the country’s road and low-volume road networks, the methodologies used in the inspection and evaluation of the latter’s condition (designed by the authors), and on data from other countries. The proposed plan involves the stages of implantation, execution and monitoring, each one with its own objectives. The possible sources of funding for such a management system – vital if its future is to be ensured – are also discussed.

Filippo Giammaria Praticò, Antonino Moro, Rachele Ammendola

It is well known that the implementation of contractor quality control/agency quality assurance (QC/QA) can support quality improvements in hot mix asphalt (HMA) pavements, both for porous European mixes (PEMs) and dense-graded friction courses (DGFCs). On the other hand, many reasons and reports highlight the importance of proper in situ air voids content, due to major influence on service properties (rate of rutting, fatigue life, structural strength, permeability, ravelling, etc.). Another relevant standpoint is that in-lab determinations of density, though often reliable and accurate, are low-speed tests. All these facts outline the potential role of field measurement of density through non-nuclear density gauges. In the light of the above facts, the main object of the paper was confined as the study of factors affecting variance and bias of non-nuclear density gauges both for PEMs and DGFCs. Bias, variance and parameters’ dependence resulted to be appreciably affected by mix typology and characteristics. In particular, when related to mix type, monovariate regressions with low-speed methods resulted able to provide a useful tool in QC/QA procedures and road asset management. Further practical applications have been outlined.