大比尺钢衬钢筋混凝土马蹄形压力管道改性试验研究

Experimental research on large-scale horseshoe section steel liner modified reinforced concrete penstock

为从根本上解决常规钢衬钢筋混凝土压力管道因运行期的裂缝过宽而带来的结构耐久性问题,采取将常规混凝土改性为高性能的钢纤维混凝土或钢纤维自应力混凝土的方法。以某水电站全背坝面管为原型,以1:10缩尺制作了钢衬钢筋钢纤维混凝土压力管道模型和钢衬钢筋钢纤维自应力混凝土压力管道模型。试验结果表明,改性为钢纤维混凝土的压力管道表现出很好的限裂能力,其初裂荷载有一定的提高,管道裂缝宽度显著下降;改性为钢纤维自应力混凝土的压力管道表现出很好的抗裂能力,管道的初裂荷载有了大幅度的提高,钢材的性能也得到了较充分的利用。模型试验的结果显示了改性钢衬钢筋混凝土压力管道良好的应用前景。

For purpose of solving the problem of durability for conventional steel lined reinforced concrete penstock,steel fiber concrete and steel fiber reinforced self-stressing concrete were adopted to control crack width of out packed reinforced concrete. Based the prototype of penstocks of a hydropower station,two 1：10 reduced scale test members were produced to investigate the structural behavior of steel lined reinforced concrete penstock.Test results show that steel fiber reinforced concrete penstock presented very excellent properties of crack resistance,the initial cracking loads of penstocks increased and the concrete cracking significantly decreased.For steel fiber reinforced self-stressing concrete penstock,the initial cracking loads remarkably improved and the strength of steel material was fully used.The test results also show that both high-performance concrete provided good future in application of steel lined reinforced concrete penstock.