灌浆料养护方法及注意事项(国外英文资料).docVIP

灌浆料养护方法及注意事项(国外英文资料) Maintenance methods of grouting material and matters needing attention Two broad principles of conservation are now discussed, which differ greatly from the actual operation, depending on the site conditions, the size, shape and location of the grouting material. Maintenance methods can be summarized separately for water conservation and membrane maintenance. The first method is to provide moisture for the grouting material. The method needs continuous contact between the surface of the grouting material and water for a certain time, and starts maintenance when the surface of the grouting material is no longer vulnerable. The method can be realized by spraying water or storing water, or covering wet sand or wet soil, sawdust or straw. It should be noted that some maintenance may cause grout to change colour. Maintenance can also be done with regular wet, clean linen or cotton mats (thick and continuous lapped), or water absorbing panels that are in contact with water and placed on grout. Water hoses may be used on sloping or vertical surfaces. Continuous water conservation is more effective than intermittent water conservation, and experts compared the strength development of two kinds of cylindrical grouting specimens that were originally 24h, preserved and covered with wet cloth. When the water cement ratio is below 0.4, the moisture content in the grouting material is not obvious because of drying. Further, the grouting material with low water cement ratio needs water conservation. Attention should be paid to the quality of water conservation, in theory, should be the same as the quality of mixed water. Sea water causes corrosion of steel bars. Similarly, iron or organic matter causes discoloration of the grout, especially when water flows slowly through the surface of the grout. In some cases, discoloration is not important. Whether or not discoloration occurs cannot be determined only by chemical analysis, but should be tested by performan