国产精品日日夜夜_特级丰满少妇一级aaa爱毛片_中文字幕精品一区二区精品_中文字幕人成乱码在线观看_亚洲国产成人91porn_寡妇喂奶挤奶水在线播放

In the construction of sliding form method, the effect of adding retarder in cement concrete is to adjust the setting time of concrete, so that it matches the time of concrete pouring and sliding formwork upward. If the concrete is too fast, the formwork may not move, or the concrete wall may be pulled apart.

In the process of Slipform construction, strict construction organization and design must be carried out, strict construction scheme must be formulated, problems that may be encountered in the construction process should be formulated in advance, so as to ensure the smooth progress of the construction process under special climatic conditions without any quality problems.

In summer construction, because the daytime temperature is generally above 30 C, the cement hydration speed is very fast. For some large volume concrete projects or concrete projects with special requirements, there are specific requirements for the setting time of concrete, retarder is indispensable in the construction process of these projects. Therefore, a large number of tests must be done before construction. According to the local raw materials, climate and construction conditions, reasonable selection of additives, especially the variety and content of Retarder in additives, has a great impact on the performance of concrete. It should be determined by experiments and adjusted continuously with the change of climate so as to ensure the smooth construction of the project.