大足石刻砂岩模拟裂隙灌浆试验

裂隙渗水是导致世界文化遗产大足石刻文物破坏的一个重要因素。将一种无机环保的改性偏高岭土灌浆材料拟用于大足石刻保护工程,为研究该新型材料的可灌性,进行了室内模拟裂隙灌浆试验。通过石刻砂岩岩板控制裂隙的张开度,着重研究此种材料不同水灰比的浆液在不同灌浆压力、灌浆时间下的灌浆过程及浆体进入裂隙的最小宽度。试验表明浆液能进入的裂隙最小宽度值与水灰比、灌浆压力和灌浆时间均有关;水灰比是控制浆液可灌性的首要因素,而压力的提高并不能显著提高灌浆速度;提高水灰比、灌浆压力及灌浆时间均可改善细小裂隙的灌浆效果。

Simulation of Fracture Grouting Test for Sandstones of Dazu Rock Carvings

Seepage from sandstone fractures is an important cause of the deterioration of Dazu rock carvings, a world cultural heritage site. Fractures grouting is a traditional and effective way for the treatment of fracture seepage. A modified inorganic and environmental composite material of Metakaolin has been proposed for the grouting in the fractures of Dazu carvings. In this research, laboratory test with a man-made fracture was conducted to study the groutability of this material. By controlling the opening of fracture through two sandstone slates, the grouting procedure and minimum span of the artificial fracture were recorded to study the influence of water-cement ratio, grouting pressure and grouting duration. Results reveal that the minimum width that the slurry can flow into is controlled by the water-cement ratio, grouting pressure and grouting duration. Among the three factors, water-cement ratio plays a dominant role; while increasing the grouting pressure cannot improve the grouting efficiency obviously; raising the water-cement ratio and pressure or extending the grouting duration could improve the groutability of slurry in small fractures.