1. The coarse aggregate should be continuously graded and the fine aggregate should be medium sand.

2、外加劑宜采用緩凝劑、減水劑；摻合料宜采用粉煤灰、礦渣粉等。

2. Retarder and water reducer should be used as additives; Fly ash and slag powder should be used as admixture.

3、機場道面商品混凝土在保證商品混凝土強度及坍落度要求的前提下，應提高摻合料及骨料的含量，以降低商品混凝土的水泥用量。

3. On the premise of ensuring the strength and slump of commercial concrete, the content of admixture and aggregate should be increased to reduce the cement consumption of commercial concrete.

4、水泥應盡量選用水化熱低、凝時間長的水泥，優先采用中熱硅酸鹽水泥、低熱礦渣硅酸鹽水泥、大壩水泥、礦渣硅酸鹽水泥、粉煤灰硅酸鹽水泥、火山灰質硅酸鹽水泥等。

4. Cement with low hydration heat and long setting time shall be selected as far as possible, and medium heat Portland cement, low heat slag Portland cement, dam cement, slag Portland cement, fly ash Portland cement, pozzolanic Portland cement, etc. shall be preferred.

但是，水化熱低的礦渣水泥的析水性比其它水泥大，在澆筑層外表有少量水析出。這種泌水現象，不只影響施工速度，同時影響施工質量。因析出的水聚集在上下兩澆筑層外表間，使商品混凝土水灰比改動，而在掏水時又帶走了一些砂漿，這樣便構成了一層含水量多的夾層，破壞了商品混凝土的粘結力和整體性。

However, the slag cement with low hydration heat has higher water evolution property than other cement, and there is a small amount of water precipitation on the surface of pouring layer. This kind of bleeding not only affects the construction speed, but also affects the construction quality. Due to the precipitation of water gathered between the surface of the upper and lower pouring layers, the water cement ratio of commercial concrete is changed, and some mortar is taken away when water is extracted, thus forming a layer of interlayer with more water content, which destroys the cohesive force and integrity of commercial concrete.

商品混凝土泌水性的大小與用水量有關，用水量多，泌水性大；且與溫度高低有關，水完全析出的時間隨溫度的提高而延長；此外，還與水泥的成分和細度有關。所以，在選用礦渣水泥時應盡量選擇泌水性的種類，并應在商品混凝土中摻入減水劑，以降低用水量。在施工中，應及時排出析水或拌制一些干硬性商品混凝土平均澆筑在析水處，用振搗器振實后，再繼續澆筑上一層商品混凝土。

The amount of bleeding of commercial concrete is related to the water consumption, which is more than water consumption; The time of complete precipitation of water increases with the increase of temperature; In addition, it is also related to the composition and fineness of cement. Therefore, in the selection of slag cement, the type of bleeding should be selected as far as possible, and water reducing agent should be added into commercial concrete to reduce water consumption. During the construction, it is necessary to drain the water or mix some dry and hard commercial concrete in time, and pour it evenly at the water drainage place, and then continue to pour the upper layer of commercial concrete after vibrating with vibrator.