Effect of Surface Blasting on Subway Tunnels- A Parametric Study

نوع مقاله: مقاله پژوهشی

نویسندگان

Dept. of Civil, Yazd University, Iran

چکیده

During wars and crises, the underground tunnels are used as a safe space. Therefore, the stability and safety of them under a blast is of particular importance. In this paper, the Finite Difference Method has been used to study the influence of the change in geotechnical parameters and depth on surface blasting on subway tunnels. Results showed that increasing the internal friction angle, modulus of elasticity and cohesion of the soil reduced the effects of blast loads on the vertical displacement and bending moment in the center of tunnel crown. Furthermore, the results showed that increasing the depth of the tunnel reduced the effects of blast loading. Comparing all parameters collectively showed that the increase in the modulus of elasticity of the soil and depth of the tunnel is the most effective in reducing the influence of the blast loads on the vertical displacement and bending moment of the tunnel crown, respectively.

کلیدواژه‌ها


عنوان مقاله [English]

Effect of Surface Blasting on Subway Tunnels- A Parametric Study

نویسندگان [English]

  • Hossein Entezari Zarch
  • Kazem Barkhordari
Dept. of Civil, Yazd University, Iran
چکیده [English]

During wars and crises, the underground tunnels are used as a safe space. Therefore, the stability and safety of them under a blast is of particular importance. In this paper, the Finite Difference Method has been used to study the influence of the change in geotechnical parameters and depth on surface blasting on subway tunnels. Results showed that increasing the internal friction angle, modulus of elasticity and cohesion of the soil reduced the effects of blast loads on the vertical displacement and bending moment in the center of tunnel crown. Furthermore, the results showed that increasing the depth of the tunnel reduced the effects of blast loading. Comparing all parameters collectively showed that the increase in the modulus of elasticity of the soil and depth of the tunnel is the most effective in reducing the influence of the blast loads on the vertical displacement and bending moment of the tunnel crown, respectively.

کلیدواژه‌ها [English]

  • Blast Loading
  • Subway Tunnels
  • finite difference method
  • dynamic analysis
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