The acoustic climate of spaces located under overpasses in the context of adapting them for outdoor public events – a pilot case study

Due to the current shortage of traditional public space because of its privatization, commercialization, and securitization, there is an urgent need to reclaim areas affected by motorized traffic in the urbanized areas. On the other hand, the process of adapting them for new purposes should be carefully carried out, addressing several issues, among them environmental acoustics. This study is meant to contribute to our understanding of acoustic conditions of a general model of the bridge underspace. Therefore, the aim of the research was to examine the existing acoustic climate by measuring noise levels and comparing them with equivalent acceptable noise levels for the expected type of space development and Noise Rating curves. In this research, a pilot case study approach was used, as measurements were taken for a chosen space located under an elevated road that represents certain criteria set by the researchers. The results allowed us to: (1) verify the relationship between the geometry of the bridge underspace and the noise levels, (2) assess the initial acoustic conditions in terms of possibilities of acoustic adaptation of the examined space for outdoor public events, and (3) formulate hypotheses and preliminary assumptions for the planned further and broader studies of the issues raised in this article. The presented results and their analysis show that it is possible to bring the acoustic conditions in the studied space to the state required for public or cultural meeting spaces. In comparison with earlier findings, the research undertaken appears to be pioneering and the results can be used as valuable input for further research on this topic.

Structural Optimization of Road Fully Enclosed Sound Barrier Based on Three-Dimensional Finite Element Analysis

With the help of the finite element analysis software ANSYS, this paper establishes a finite element model of a fully enclosed sound barrier of elevated road, calculating and analyzing the stress of supporting structure under different working conditions, checking the strength, stiffness and stability of the structure under the most unfavorable working condition. Finally we optimize the structure according to its characteristics.

Penggunaan CSS-Mortar Busa Sebagai Alternatif Pemilihan Tipe Konstruksi Jalan Layang terhadap Biaya Konstruksi

The elevated road construction which is originally intended to overcome congestion at the intersection of the highway/train, actually sometimes worsen the congestion that exists during the construction period. Therefore, a new construction method and technology is needed to minimize the congestion and provide a short construction period. CSS-Mortar Foam is a new technology introduced by the Research Center of the Ministry of PUPR (Pusjatan) in 2016 which has been applied to the construction of the Antapani flyover in Bandung. A study is needed to compare the construction cost of this technology with the technology of the overpass structure which is commonly used, namely PCI-Girder. Data collection process in this study are planning and DED data, inventory of work items and volumes, and the unit price. The next step is the construction-costs calculation process of the proposed alternative-construction types. The calculation of construction costs was carried out using the Work Unit Price Analysis (AHSP) which is developed by the Directorate General of Highways based on the third revision of 2010 General Specifications. The results showed that the alternative CSS-Mortar Foam construction types was able to reduce the construction costs of flyovers by 44.7% compared to the PCI-Girder construction type. Thus, CSS-Mortar Foam construction can be used as a more efficient alternative for flyovers/bridges construction.

Assessing the tsunami mitigation effectiveness of the planned Banda Aceh Outer Ring Road (BORR), Indonesia

This research aimed to assess the tsunami flow velocity and height reduction produced by a planned elevated road parallel to the coast of Banda Aceh, called the Banda Aceh Outer Ring Road (BORR). The road will transect several lagoons, settlements, and bare land around the coast of Banda Aceh. Beside its main function to reduce traffic congestion in the city, the BORR is also proposed to reduce the impacts of future tsunamis. The Cornell Multi-grid Coupled Tsunami Model (COMCOT) was used to simulate eight scenarios of the tsunami. One of them was based on the 2004 Indian Ocean tsunami. Two magnitudes of earthquake were used, that is, 8.5 and 9.15 Mw. Both the earthquakes were generated from the same source location as in the 2004 case, around the Andaman Sea. Land use data of the innermost layer of the simulation area were adopted based on the 2004 condition and the land use planning of the city for 2029. The results of this study reveal that the tsunami inundation area can be reduced by about 9 % by using the elevated road for the earthquake of magnitude 9.15 Mw and about 22 % for the earthquake of magnitude 8.5 Mw. Combined with the land use planning 2029, the elevated road could reduce the maximum flow velocities behind the road by about 72 %. Notably, the proposed land use for 2029 will not be sufficient to deliver any effects on the tsunami mitigation without the elevated road structures. We recommend the city to construct the elevated road as this could be part of the co-benefit structures for tsunami mitigation. The proposed BORR appears to deliver a significant reduction of impacts of the smaller intensity tsunamis compared to the 2004 Indian Ocean tsunami.

Assessing the tsunami mitigation effectiveness of a planned Banda Aceh Outer Ring Road (BORR), Indonesia

This research aimed to assess the tsunami flow velocity and height reduction produced by a planned elevated road spanned parallel to the coast of Banda Aceh called Banda Aceh Outer Ring Road (BORR). Cornell Multi-Grid Coupled Tsunami Model (COMCOT) was used to simulate eight scenarios of the tsunami. One of them was based on the 2004 Indian Ocean tsunami. Two magnitudes of earthquake were used, that is, 8.5 and 9.15 Mw. Both the earthquakes were generated from the same source location as in the 2004 case, around the Andaman Sea. Land use data of the innermost layer of the simulation area were adopted based on the 2004 condition and the land use planning of the city for 2029. The results of this study reveal that the tsunami flow depths and flow velocities can be reduced by about 9 % by using the elevated road for earthquake magnitude 9.15 Mw and about 22 % for earthquake magnitude 8.5 Mw. Combined with the land use planning 2029, the elevated road could reduce the maximum flow velocities behind the road by about 72 %. Notably, the proposed land use for 2029 will not be sufficient to deliver any effects on the tsunami mitigation without the elevated road structures. We recommend the city to construct the elevated road as this could be part of the co-benefit structures for tsunami mitigation. The proposed BORR appears to deliver significant reduction of impacts in the smaller intensity tsunamis compared to the 2004 Indian Ocean tsunami.

Prediction of Daily Entrance and Exit Passenger Flow of Rail Transit Stations by Deep Learning Method

The prediction of entrance and exit passenger flow of rail transit stations is one of key research focuses in the area of intelligent transportation. Based on the big data of rail transit IC card (Public Transportation Card), this paper analyzes the data of major dynamic factors having effect on entrance passenger flow and exit passenger flow of rail transit stations: weather data, atmospheric temperature data, holiday and festival data, ground index data, and elevated road data and calculates the daily entrance passenger flow and daily exit passenger flow of individual rail transit stations with data reduction. Furthermore, based on the history data of passenger flow of rail transit stations and relevant influence factors, it applies the deep learning method to choose the relatively optimal hidden layer node by means of the cut-and-try method, set up input data and labeled data, select the activation function and loss function, and use the Adam Gradient Descent Optimization Algorithm for iterative global convergence. The results verify that this method accurately predicts the daily entrance passenger flow and daily exit passenger flow of rail transit stations with the prediction error of less than 4.1%. Finally, the proposed model is compared with the linear regression model.

Challenges in Design & Construction of Elevated Grade Separators with Wide Deck & Single Central Pier, in urban areas.

<p>India’s transport sector is large and diverse; it caters to the needs of 1.25 billion people. Roads are the dominant mode of transportation in India today. They carry almost 90 percent of the country’s passenger traffic and 65 percent of its freight. Cognizant of the need to create an adequate road network to cater to the increased traffic and movement of goods, Government of India has recently allotted Rs 640 billion (US$ 9.55 billion) to National Highway Authority of India (NHAI) for roads and highways and Rs 270 billion (US$ 4.03 billion) for rural roads under PMGSY scheme (as on 20th April 2017). One of the impediment in the fast progress of road infrastructure is acquisition of land &amp; related regulatory hurdles. Completion of as many as 112 projects of NHAI is delayed on account of such factors. There is a restriction of the available width and to spread the road horizontally. Therefore, present trend in urban areas is to go for elevated grade separators, wherein both surface level as well as elevated road can be fully utilised for traffic movement. By avoiding costly land acquisition, it results in reduction in cost of the project and certainly segregate local and fast moving traffic, thereby further increasing speed of movement. Design and Construction of such elevated corridors however poses many challenges to structural engineers. Restricted work space during construction adds to the challenge and brings out many innovative solutions to the problems. This paper discusses case studies of number of such projects for which the authors are presently associated in design and construction planning. These projects are in various stages of construction.</p>