Equipment World Digital Magazine
Issue link: http://read.dmtmag.com/i/506694
EquipmentWorld.com | April 2015 45 4 Use of Rocket Traction Method to Span Pilot Rope for Long Span Suspension Bridge Construction in Mountainous Area[s], by Dajin Guo and Xiao Li, National Engineering Laboratory For Surface Transportation Weather Impacts Prevention, Tuodong Rd., China; Wenhuan Zhou and Mingfang Hu, Re- search Institute of Highway, Ministry of Transport, Beijing; Zhengfu Yu and Guobang Xia , Puxuan Highway Project Headquarters of Yunnan Province; Wei Liu, Beijing Zhongjiao Ruida Technology Co., Ltd., Beijing; and Biyu Yang, Department of Transport of Yunnan Province, Kunming. topconpositioning.com TOPCON EXCAVATOR CONTROL SYSTEMS The enhanced productivity of 3-D control is a well-known fact. But what's often overlooked is the beauty of its precision. Get the confidence to tackle any job with ease, and the most demanding ones with a smile. THE EARTH IS YOUR CANVAS s 4HE CONlNING PRESSURE EXERTED BY PRESTRESSING STRANDS IS AD- EQUATE FOR SHEAR TRANSFER BETWEEN THE STEEL JACKETING AND COLUMN NO ADHESIVE EPOXY OR DOWEL REINFORCEMENT IS REQUIRED s 3HEET METAL PROVIDES THE RE- QUIRED BEARING STRENGTH AND PREVENTS COVER CONCRETE SPALLING AND PENETRATION OF THE PRESTRESS- ING CABLES s 0RESTRESSING CABLES COULD SUSTAIN THE ACTIVE CONlNING PRESSURE UP TO PERCENT LATERAL DRIFT WITH NO SIGNIlCANT PRESTRESSING FORCE LOSS Build remote suspension bridges using rocket-powered cables #HINAS CENTURIESOLD PROWESS IN GUNPOWDER AND lREWORKS NOW HAS A NEW APPLICATION THE USE OF ROCKETS TO lRE THE hPILOTv OR INITIAL GUIDE ROPES FOR SUSPENSION BRIDGES ACROSS VOIDS IN REMOTE MOUNTAINOUS AREAS ACCORD- ING TO A 42" PAPER FROM #HINA 4 4HERE ARE MANY PILOT ROPE ERECTION METHODS AS PART OF THE SUSPENSION BRIDGE CONSTRUCTION THESE INCLUDE WATER TOWING MANUAL HAULING AND AIR TRACTION THE AUTHORS SAY "UT THESE ALL MAY NOT BE AVAILABLE FOR CONSTRUC- TION OF SUSPENSION BRIDGES IN RUGGED REMOTE AREAS NOW BEING REACHED BY #HINAS GROWING HIGHWAY SYSTEM h&OR CONSTRUCTING LONGSPAN SUSPENSION BRIDGE;S= ERECTION OF ;A= PILOT ROPE IS THE lRST STEP OF THE SUPERSTRUCTURE CONSTRUCTION WHICH PROVIDES THE FOUNDATION FOR THE LOADBEARING CABLE CATWALK TRACTION SYSTEM TO BE CONSTRUCTED ;FOLLOW- ING= THE PILOT ROPEv THE AUTHORS NOTE h(OWEVER ERECTION OF PILOT ROPE UNDER CERTAIN MOUNTAINOUS TERRAIN CONDITIONS CAN BE EXTREMELY CHALLENGINGv 4HE 9UNNAN 0ULI LONG SPAN BRIDGE IS A FOOT SUSPENSION BRIDGE IN THE +ARST REGION OF #HINA CROSS- ING A CANYON MORE THAN FEET AND EXTREMELY STEEP ON BOTH SIDES %VERCHANGING WEATHER AND THICK VEGETATION COVERING THE GROUND MADE IT DIFlCULT TO ERECT THE PILOT ROPE USING THE TRADITIONAL METHODS !FTER COMPARING THREE TYPES OF ERECTION METHODS THE RESEARCHERS EXPERIMENTED WITH THE ROCKET TRAC- TION METHOD FOR ERECTING THE PILOT ROPE 4HE PROJECT DEMONSTRATED THAT THE ROCKET TRACTION METHOD HAS BENElTS INCLUDING EASY PREPARA- TION FAST ERECTION IS COSTEFFECTIVE AND ENVIRONMENTALLY FRIENDLY AND IS PARTICULARLY SUITED FOR USE IN THE MOUNTAINOUS REGION