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Sustainable Infrastructure: Climate Changes and Carbon Dioxide
Issue:
Volume 5, Issue 5, September 2017
Pages:
254-267
Received:
13 August 2017
Published:
14 August 2017
Abstract: Civil infrastructure provides the physical backbone of all societies. Water supply, wastewater treatment, transportation systems, and civil structures must be sustainable over multiple decades (e.g. 20, 30, 50 years) for human populations to survive and flourish. Over such a long time-period, climate changes are inevitable. The global atmospheric system is dynamic. Weather and climates are constantly adjusting. To date the effects of carbon dioxide have been evaluated almost exclusively using a global reference frame. However, civil infrastructure is stationary and local in nature. A locational reference frame is introduced here as an alternative framework for evaluating the effect of carbon dioxide on civil infrastructure. Temperature data from the City of Riverside, California from 1901 to 2017 are analyzed to illustrate application of a local reference frame. No evidence of significant climate change beyond natural variability was observed in this temperature record. Using a Climate Sensitivity best estimate of 2°C, the increase in temperature resulting from a doubling of atmospheric CO2 is estimated at approximately 0.009°C/yr which is insignificant compared to natural variability.
Abstract: Civil infrastructure provides the physical backbone of all societies. Water supply, wastewater treatment, transportation systems, and civil structures must be sustainable over multiple decades (e.g. 20, 30, 50 years) for human populations to survive and flourish. Over such a long time-period, climate changes are inevitable. The global atmospheric s...
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Telecommunication Cell Tower Most Common Alternatives Overview
Al-jassani Azhar Abdulkareem Majeed,
Al-suraifi Inam Jabbar Hraba
Issue:
Volume 5, Issue 5, September 2017
Pages:
268-281
Received:
24 June 2017
Accepted:
3 August 2017
Published:
25 August 2017
Abstract: The main goal of this review is to decide which alternatives could be the most proper structural system type for 36 m tower height and practical specified deflection limit “Torsional Effect” at the tower top less than 0.5 degree to be used in a rural zone near of Budapest City, Hungary based on the most common control aspects (Aesthetical, Economical and Statical aspect) which influences the decision making and the selection process. According to that purpose a different tower types have been reviewed in detail (Lattice towers, Monopole and Guyed mast) in order to decide which alternatives could be selected for further investigations based on the limitations and requirements of the present case of study, where every alternative has it features, benefits and Specific limits of application. The resulted decision based on the presented study was that the most proper alternatives according to the specified information are the lattice towers (Square & Triangular) and the Monopole which deserve to be selected for further investigations.
Abstract: The main goal of this review is to decide which alternatives could be the most proper structural system type for 36 m tower height and practical specified deflection limit “Torsional Effect” at the tower top less than 0.5 degree to be used in a rural zone near of Budapest City, Hungary based on the most common control aspects (Aesthetical, Economic...
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Pedestrian Flow Characteristics Under Heterogeneous Traffic Conditions
A. M. Tahsin Emtenan,
Showkat Ibne Shahid
Issue:
Volume 5, Issue 5, September 2017
Pages:
282-292
Received:
3 July 2017
Accepted:
16 August 2017
Published:
28 August 2017
Abstract: Pedestrians are an important element of the traffic stream especially in a country like Bangladesh. Dhaka is the biggest metropolitan city of Bangladesh and thus people from different parts of the country are relocating to Dhaka. This has rendered Dhaka one of the most densely populated cities in the World. With the resource restraint and crumbling infrastructure, the transportation facilities can’t cope up with the ever growing population. A major proportion of the population are the urban slum dwellers and low income people who are left with the only option of walking. Pedestrians are the most vulnerable roadway users. Ironically they are not given due consideration in the design of roadway features. However, the alarming growths of pedestrians, inadequate sidewalks and their haphazard movement have forced them to share the carriageway with the vehicles. This has led to a shocking number of accidents in the past as well as contributed to further increasing the congestion on the carriageway. This study has attempted to present flow characteristics of pedestrians on exclusive sidewalks in three important urban areas of Dhaka namely Farmgate, Shahbag and Shukrabad. Pedestrian flow, density and walking speed are considered as the three primary parameters on which the flow characteristics depend. These are essential tools for determining the sidewalk capacity which will help in sidewalk design improvements required. The relationships between the three parameters were expressed in terms of three equations which makes it easy to comprehend the situations in these three locations. The level of service (LOS) has been determined at each location also. On the basis of flow rate, Farmgate has a LOS C and Shukrabad and Shahbag both have a LOS B. The average free-flow speed from three locations is about 1.18 m/s. This might help create an idea about the rate at which pedestrians might clear out from facilities.
Abstract: Pedestrians are an important element of the traffic stream especially in a country like Bangladesh. Dhaka is the biggest metropolitan city of Bangladesh and thus people from different parts of the country are relocating to Dhaka. This has rendered Dhaka one of the most densely populated cities in the World. With the resource restraint and crumbling...
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Incorporation of “Risk Factor” in Design Flood Review of Existing Dams
Ravi Kumar Pillai,
Om Prakash Gupta
Issue:
Volume 5, Issue 5, September 2017
Pages:
293-306
Received:
31 July 2017
Accepted:
21 August 2017
Published:
8 September 2017
Abstract: At present there are about 4877 completed large dams in India. More than 75% of Indian dams are at least two decades old and for these dams the original design floods call for revisions. Examination of revised design flood studies carried out for a set of 118 dams under ‘Dam Rehabilitation and Improvement Project (DRIP)’ reveal that the design flood values have increased substantially with trends indicating that percentage increases in the revised design flood values are greater for lower dams and also for older dams. Paper illustrates that the upward revision in the design flood estimate of existing dam in no way leads to amplification of the actual risk associated with that dam, and it only underlines the gap between the acceptable risk level and existing risk level. The paper shows that flood related risk mitigation of existing dams is a challenging task often facing constraints of technical and economical viabilities. With the substantial data set of design flood revisions of DRIP dams, the paper brings out the skew observed in distribution of revised design floods on account of present-day norms related to computation of design floods, as contained in the Indian Standard IS: 11223 – 1985 (reaffirmed 1995). Paper also proposes amendments in this Standard in respect of existing large dams with an alternative recourse of formulating a new Standard for revision of design floods incorporating the risk factor associated with these large dam structures.
Abstract: At present there are about 4877 completed large dams in India. More than 75% of Indian dams are at least two decades old and for these dams the original design floods call for revisions. Examination of revised design flood studies carried out for a set of 118 dams under ‘Dam Rehabilitation and Improvement Project (DRIP)’ reveal that the design floo...
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Study on Landslide Mechanism and Treatment Technology in Tunnel of Sandy Cobble Stratum
Li Borong,
Yao Hongzhi,
Gong Juan
Issue:
Volume 5, Issue 5, September 2017
Pages:
307-314
Received:
21 September 2017
Published:
22 September 2017
Abstract: The steady ability of sandy pebble stratum is poor, during the tunnel construction, landslides occur frequently. In order to clarify the mechanism of landslide in sand gravel tunnel and put forward effective treatment technology, the paper takes the Gongboxia tunnel, which located in Qinghai Province, as the engineering background. In view of the landslide in tunnel, the influence factors and formation instability model are analyzed, also the comprehensive treatment technology of landslide is put forward. The results show that the geological factors are the main factors of tunnel collapse, design factors and construction factors contributed to the collapse of the tunnel collapse to a certain extent, the interaction of multiple factors; sand gravel stratum collapse mechanism belongs to loose medium caving, the instability mode is gravity collapse; based on the analysis of tunnel collapse mechanism. Put forward the "dense row of short pipe shed, three bench reservation core soil + locking anchor pipe, grouting backfill, the temporary support" comprehensive treatment technology, through on-site data reflect, have very strong practicability and pertinence. The research results can provide the material of engineering analogy for the design and construction of similar projects, and have important reference significance.
Abstract: The steady ability of sandy pebble stratum is poor, during the tunnel construction, landslides occur frequently. In order to clarify the mechanism of landslide in sand gravel tunnel and put forward effective treatment technology, the paper takes the Gongboxia tunnel, which located in Qinghai Province, as the engineering background. In view of the l...
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