نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشگاه صنعتی مالک اشتر
2 مدیر مرکز پژوهشی علوم و فناوری مهندسی زمین امن
3 سایر/سایر
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Bridges are one of the key elements in a country’s transportation network; thus, they are the first targets of exsplosive
attacks on transport infrastructure. Destruction of bridges in a network leads to a significant reduction in access and
latency in the transmission. In order to counteract and mitigate the consequences of these types of threats, it is essential
to meet the requirements for designing and constructing optimal structures resistant to explosive waves. Despite the rising
number of such threats every day around the world, there has been very limited research on the risk assessment of the
bridge. In this research, along with a review of a variety of risk assessment methods, the method proposed in the FEMA452 instruction
was selected due to its rationale, comprehensiveness and ease of use. In order to determine the importance
of vulnerable bridges, a questionnaire was developed based on FEMA criteria and was made available to experts. In this
questionnaire, network threats were first identified and ranked, and then, the value of bridge assets was investigated and
the probable vulnerability was calculated in each threat scenario. In order to evaluate the results, one of the bridges of
Dorood-Khorramabad railway route was selected as the case study and risk calculations were made on its components.
The results of the analyses revealed the risk number of 250 as the threshold for identifying assets of high and ultra high
risks. Accordingly, the deck and column introduced the highest risk number by applying the coefficient of threat, asset
value, and vulnerability. In order to analyze the breakdown of the bridge due to the explosion, version 15 of ANSYS software was used. In this
regard, the bridge was modeled and the assets with a higher risk than the specified value were subjected to the loads
of explosion of different values of the TNT. Then, the bridge behavior of the overall stability and concrete damage was
noticed. By reviewing the results of modeling, solutions to reduce the risk of explosive threats have been presented, which
will help to continue the service of the bridge in the time of crises.
کلیدواژهها [English]
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