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  ______     ___      ____     _    _    _    _   
 /_   _//   / _ \\   |  _ \\  | || | || | |  | || 
 `-| |,-   | / \ ||  | |_| || | || | || | |/\| || 
   | ||    | \_/ ||  | .  //  | \\_/ || |  /\  || 
   |_||     \___//   |_|\_\\   \____//  |_// \_|| 
   `-`'     `---`    `-` --`    `---`   `-`   `-`

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發送短信 : Effect of braced excavation on tunnels in clay