英语翻译The bridge’s orginal abutments were modified two-column bents with rock masonry retaining walls holding back the roadway fill.The retrofit required abutments that would be very strong and stiff during seismic events while allowing free

英语翻译The bridge’s orginal abutments were modified two-column bents with rock masonry retaining walls holding back the roadway fill.The retrofit required abutments that would be very strong and stiff during seismic events while allowing free
英语翻译
The bridge’s orginal abutments were modified two-column bents with rock masonry retaining walls holding back the roadway fill.The retrofit required abutments that would be very strong and stiff during seismic events while allowing free thermal movements during the sevicelife of the bridge.Consequently,floating slabs 4 to 6 ft(1 to 2 m) deep were made continuous with the deck and serve as the anchrage blocks for the main deck prestrssing .Each slab floats atop a keyed pile cap.with six 72 in.(1,829 mm)dianmeter CIDH piles extending 35 ft (11 m)into the ground .Seismic loads are transferred between the deck element and the foundation piles by heavily reinforced shear keys that lock the floating slab to the pile cap .Small gaps of 0.5 to 1.25 in .(12.7 to 31.75 mm) in the key system allow both transverse and longitudinal movements in reponse to thermal loading without imposing extra stress on the bridge .Reinforced elastomeric pads expanded polyrene between the fixed and floating elements faxilitate these small movements.
The magnitude of the seismic loads and the stiffnesses necessary to resist them are reflected in the sizes of the piles .Because of the large fixed-end moments form the piles,the pile caps were prestressed in both horizontal directions.
The floating slab key system also solved another design issue facing the engineers.The shortening of the bridge during posttensioning had to be accommodated at the abutments.The use of a single monolithic abutment block would have forced the pile group to deflect and would have sucked up a good portion of the prestress force.The two-piece floating slab and pile cap system,with keys uncast,allowed the deck to contract freely during the posttensioning operations.The keys were then finished,locking up the seismic load path.

英语翻译The bridge’s orginal abutments were modified two-column bents with rock masonry retaining walls holding back the roadway fill.The retrofit required abutments that would be very strong and stiff during seismic events while allowing free
桥的 orginal 邻接被修正二-专栏弯曲以岩石 masonry 保有墙壁握住车道填充的背面.当在 bridge.Consequently 的 sevicelife 期间允许自由的热运动的时候 ,式样翻新需要了邻接以会在地震的事件期间非常强壮的和强烈,深的漂浮平板 4 到 6 ft(1 到 2 m) 为主要的甲板 prestrssing 由于甲板和服务被做连续如 anchrage 区段.每平板漂流物在顶上一键入堆起 cap.with 六 72 在.(1,829 毫米) dianmeter CIDH 堆扩充 35 ft(11 m) 进地面之内.地震的负荷在甲板元素和基础堆之间被很重地加强的修剪锁对堆无边帽的漂浮平板的钥匙转移.0.5 到 1.25个的小缝隙在.(12.7 到 31.75 毫米) 在主要系统中不强迫在桥上的额外压迫力而允许对热的载入在 reponse 的横和纵观的运动.加强人造橡胶的填补扩大了在固定的和漂浮的元素 faxilitate 之间的 polyrene 这些小的运动.
对抵抗他们是必需的地震负荷的大小和坚硬在堆的大小方面被反映.因为那大的修理-结束片刻形成堆,堆无边帽在两者的水平方向中被预力.
漂浮的平板钥匙系统也解决了另外的一个设计议题面对工程师.桥的弄短在 posttensioning 期间必须在邻接被适应.单一独石的邻接区段的使用会压迫堆团体使会在预力力量的好部分上面吸偏斜并且.上下两件的漂浮平板和堆无边帽系统,藉由钥匙不投,允许了甲板在 posttensioning 操作期间自由地缩短.钥匙然后被完成,锁定提高地震的负荷路径.