钢板-超薄UHPC-TPO组合桥面静力和疲劳试验研究

为探明钢-超薄UHPC （Ultra-high Performance Concrete）-TPO （Thin Polymer Overlay）组合桥面基本力学性能,设计5块钢-超薄UHPC-TPO组合板进行抗弯静力试验及疲劳试验。静力试验结果表明：在负弯矩作用下,UHPC层的开裂强度为22.1～24.3MPa;TPO先于UHPC进入非线性阶段。疲劳试验结果表明：若将此方案应用于虎门大桥悬索桥,则UHPC层在设计应力幅下疲劳开裂寿命可达925.7万次,TPO层将不会因疲劳而开裂;疲劳加载后,组合板剩余弯拉强度均值为26.9kN,整体抗弯刚度与静力试验结果相比仅下降13%。研究表明,钢桥面-超薄UHPC-TPO组合桥面具有优良的抗弯拉性能。

Static and fatigue tests on composite deck with steel and ultra-thin UHPC-TPO

In order to investigate the basic mechanical performances of a composite deck with Steel and ultra-thin UHPC (Ultra-high Performance Concrete)-TPO (Thin Polymer Overlay), 5 pieces of steel- UHPC-TPO composite plate were designed, and the static bending and fatigue bending tests were carried. The static tests show that the cracking strengths of UHPC layers are between 22.1 and 24.3MPa. Under the action of negative moments, TPO enters the nonlinear phase prior to the UHPC. The fatigue tests show that for the new composite deck applied to the Humen suspension bridge, the fatigue life of the UHPC can be up to 925.7 million times, and no fatigue cracking appears in TPO under the design stress. After the fatigue loading, the residual flexural strength of the composite plates are about 26.9kN, and the bending stiffness of the composite plates is only decreased by 13% compared with the static test results. The research results indicate that the steel-ultra thin UHPC-TPO composite deck has excellent flexural performances.