modern concepts in bridge construction bridges are not only a functional part of transportation but also an identity of the place where it is built we can see numerous examples of smart bridge construction around us golden gate bridge california tower bridge london sydney harbour bridge brooklyn bridges are some of the examples all those bridges are constructed during a time of limited technologies and machinery hello i am amin ossif we are going to watch latest construction technology in today's context from the design to construction the entire concepts of bridges has been changed and it's mainly because of the advancement in technology and availability of new construction materials nowadays designers are always eager to introduce a symbolic aesthetic architecture or a unique touch to the bridge design to get people an emotional touch with it in light of advanced technology the concepts of bridge design got evolved so far we are discussing china's bridge construction technologies a video clip of chinese engineers connecting two rotating flyover sections as part of the beijing zhangjiago high-speed railway recently went viral online the amazing moment offered a glimpse into china's bridge building capabilities the work was carried out on early morning of september 17th after each section made a 31 degree turn the two elevated railways slowly swung towards each other until they met the newly connected section of railway now spans above da tonkin huango railway that has been running for years the 3503.48 meter long flyover between the tuma township and guantan reservoir in huawei county north china's hebei province crosses over datunkin huangdo railway beijing baotou railway and beijing tibet highway the dotonkin huango railway is one of the busiest lines in operation in china china is also home to seven of the world's top ten cable state bridges a monster-sized bridge building machine in action two feats of engineering the bridge that the machine is building in the machine itself this is the 580 ton 91.8 meter 301 feet long 7.4 meter 24 feet wide slj 900-32 bridge girder erection machine by the beijing wow joint machinery company this bridge building process may appear complicated but it is in fact brilliantly simple it begins when the machine picks up a new beam from the casting yard the machine drives to the side of the bridge where the pillars have already been erected it lowers a pneumatic support structure which stabilizes the machine as it extends out to the first pillar some distance away a second support structure is lowered onto the pillar at which point the first one is slid along the machine's length to the join the second at the pillar with both support structures in place the machine has a solid foundation for laying down the new beam the machine drives to the side of the bridge where the pillars have already been erected it lowers a pneumatic support structure which stabilizes the machine as it extends out to the first pillar some distance away a second support structure is lowered onto the pillar at which point the first one is slid along the machine's length to the join the second at the pillar with both support structures in place the machine has a solid foundation for laying down the new beam the machine now drives further forward carrying the beam with it the beam is lowered into place between the bridge's starting point and the first column with the beam secured the machine drives backwards taking the two portable support structures with it when it returns with another beam it drives along the first installed segment and the process is repeated to place the next beam between the first and second columns different methods of bridge construction are applied using modern gigantic machines one cast in situ method of bridge construction this method is a flexible method of bridge construction where complex and unusual geometrical shapes of dams can be constructed easily situations when it is hard to transport pre-fabricated elements either due to size or unreachability too balanced cantilever method of bridge construction this method is used for constructing bridges with span 50 to 250 meters 3 precast method of bridge construction in this method the bridge is constructed with the help of precast concrete elements the prefabrication is performed in different methods the precast elements include precast beams precast decks precast segmental decks for span by span casting method of bridge construction this method is associated with cantilever construction method but with many advancements in the technique it is considered as most economic and rapid in construction for long bridges five incremental launching method of bridge construction the incremental launching method ilm method of bridge construction is employed mainly for the construction of continuous concrete bridges or steel girder bridges the method performs the procedure in increments with this method of construction the bridge deck is built in sections by pushing the structure outwards from an abutment towards the pier method can be used for bridge decks with a length greater than 250m six cable state method of bridge construction in the cable state method of construction cables are used to carry the bridge deck from one or both sides of the supporting tower the cables carry and transfer all the loads to the foundations state method of construction is used for constructing bridges that span more than 300 meters seven arch method for bridge construction arch-shaped bridge construction is one of the most economical choices seven arch method for bridge construction arch-shaped bridge construction is one of the most economical choices when the bridge under consideration is required to cross over landscapes that are inaccessible many modern arch construction methods have made the arch construction more economical the arch construction can be built with concrete or precast concrete the cast incitive free cantilever method and slip form sections are two main construction techniques coming under arch methods thanks to watch be in touch with learners in don't hesitate to subscribe our channel for future upcomings see you next time take care thank you
2022-09-16