动水作用下水泥混凝土桥面防水黏结层的水稳定性研究

Study on Water Stability of Waterproof Bonded Layer of Cement Concrete Bridge Deck Considering Dynamic Water Action

为研究动水作用下水泥混凝土桥面防水黏结层的水稳定性,采用水敏感性测试仪模拟动水作用,对比分析了AMP-100二阶反应型桥面防水黏结剂(二阶反应型)、聚合物改性沥青基纤维增强型防水涂料(聚合物改性沥青型)和SBS热沥青共3种常用防水黏结层材料分别在干燥、真空浸水(长期作用)、动水(短期作用)、动水+浸水(短期+长期作用)和冻融等水损害条件作用下,对桥面防水黏结层拉拔和剪切强度造成的影响。结果表明:考虑短期+长期作用的水损害条件,对防水黏结层的力学性能削弱最大,对试件抗水损害要求最苛严,且其水作用方式最符合路面实际情况,故推荐该水损条件用于防水黏结层的水稳定性评价。对于二阶反应型,动水作用(第3.5 h)对力学强度的削弱约为真空浸泡作用的第45 h和第46 h;对于聚合物改性沥青,动水对力学强度的削弱约为真空浸泡第36 h和第27 h;对于SBS热沥青,动水对拉拔强度的削弱约为真空浸泡第30 h,剪切强度的削弱大于真空浸水;二阶反应型在未受到水损害作用时,其力学性能好于聚合物改性沥青型,然而在受到水损害条件作用后,其力学能力衰减较快,显著低于聚合物改性沥青。此外,SBS热沥青防水黏结层的力学性能差于二阶反应型和聚合物改性沥青。

In order to study the water stability of cement concrete bridge deck waterproof bonding layer under the action of dynamic water,the dynamic water action is simulated by using water sensitivity tester,the influences of 3 commonly used waterproof adhesive layer materials,i.e.,AMP-100 bridge deck waterproof adhesive two-order reactive type),polymer modified asphalt-based fiber reinforced waterproof coating(polymer modified asphalt type)and SBS hot asphalt on the pall-out and shear strengths of the waterproof bonding layer of bridge deck under the water damage conditions of dry,vacuum immersion(long-term action),dynamic water(short-term action),dynamic water+immersion(short-term+long-term action)and freezing-thawing are comparatively analyzed respectively.The result shows that(1)The water damage conditions considering short-term+long-term effect weakens the mechanical properties of the waterproof adhesive layer the most,and has the most stringent requirements for the water damage resistance of the specimen,and its water action mode is most consistent with the actual pavement situation of the,therefore,this water damage condition is recommended for the water stability evaluation of the waterproof adhesive layer.(2)For the two-order reaction type,the weakening of(the 3.5th hour)dynamic water on the mechanical strength is about the 45th hour and the 46th hour of vacuum immersion.For the polymer modified asphalt type,the weakening of dynamic water on the mechanical strength is about the 36th hour and the 27th hour of vacuum immersion.For SBS hot asphalt,the weakening of dynamic water on the drawing strength is about the 30th hour of vacuum immersion,and the weakening of shear strength is greater than that of vacuum immersion.(3)When there is no water damage,the mechanical properties of the two-order reaction type are better than those of the polymer modified asphalt type,but the mechanical properties of the two-order reaction type are decays rapidly after being subjected to water damage,which is significantly poor than those of polymer modified asphalt.(4)The mechanical properties of SBS hot asphalt waterproof bonding layer are poor than those of two-order reaction type and polymer modified asphalt type.