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    葛其榮¹  鄭子祥²  高  翔³  李秋生⁴  盧安琪⁵  朱  強(qiáng)⁶

（1 寧波市白溪水庫(kù)建設(shè)指揮部 315606； 2 國(guó)家電力公司華東勘測(cè)設(shè)計(jì)研究院； 3 上海勘測(cè)設(shè)計(jì)研究院； 4 水利水電第十二工程局第一分局； 5 水利部南京水利科學(xué)研究院； 6 甘肅省水科所）

 

[提要]  白溪水庫(kù)二期面板工作條件比較嚴(yán)酷，為了提高面板的質(zhì)量和耐久性，進(jìn)行了二期面板聚丙烯纖維混凝土的試驗(yàn)研究。研究表明，混凝土加入0. 9kg/m3的聚丙烯纖維后，可以明顯改善混凝土的變形性能，表現(xiàn)為減少混凝土干縮和抑制裂縫發(fā)生，增加極限拉伸率，降低彈性模量，大大提高了彎曲韌性，混凝土的耐久性顯著提高，抗凍標(biāo)號(hào)從Fl00提高到F200。加速老化試驗(yàn)證明，紫外線照射對(duì)混凝土內(nèi)部的纖維影響僅發(fā)生在淺表層3～4mm內(nèi)，對(duì)混凝土整體性能沒有影響。聚丙烯纖維混凝土施工工藝與普通混凝土基本相同。采用適當(dāng)?shù)陌韬头椒?、控制適宜的坍落度、加強(qiáng)振搗和收面工序，可以保證面板的施工質(zhì)量?；炷猎靸r(jià)僅增加約50元/ffl3。與取得的效益相比，是十分經(jīng)濟(jì)的。
[關(guān)鍵詞]  聚丙烯  纖維  混凝土  變形性能  耐久性

The working condition of second stage deck of the Baixi Reservoir is very adverse. To enhance the quality and durability of the deck, an experimental study on the polypropylene fiber reinforced concrete( PPFRC) for the deck of second stage is made. The study shows that with 0.9kg/m3 fiber, the deformation performance of the concrete can be improved significantly. The dry shrinkage and cracking of concrete are reduced, the maximum tension strain is increased, the elastic modulus is lowered and the bend toughness is raised. The durability of the concrete is also improved. The frost-resistance label increases from Fl00 to F200. Accelerated aging test proves that the effect of ultraviolent radiation on the performance of fibers inside the concrete is valid only at a thin layer with thickness of 3 to 4mm. There is no influence on the integrated performance of the concrete. The construction method of PPFRC is basically the same with that of the conventional concrete. The construction quality can be ensured if adopting proper mixing procedure, controlling the concrete slump to an appropriate level and improving the vibration and finishing. The added cost for PPFRC is only 50 yuan/m3. Comparing to the benefit,it is a quite economic solution.
Keywords:  polypropylene; fiber; concrete; deformation performance; durability