沥青的发泡特性：沥青在高温（一般为160℃左右）条件下，加入少量（2%左右)的水，由于水的急速气化，使沥青剧烈膨胀，发生“爆炸”产生大量泡沫，同时沥青表面积迅速提升，体积膨胀数倍至数十倍，但在很短的时间内（约1s）沥青又恢复原状。

The foaming characteristics of asphalt: when the asphalt is added at a high temperature (generally around 160 degrees Celsius), a small amount (2% or so) of water is added. Due to the rapid gasification of water, the asphalt expands drastically, and a large number of bubbles are generated by the "explosion". At the same time, the asphalt surface area rapidly increases and the volume expands several times to tens of times, but in a very short period of time (about 1s) the asphalt is restored to its original state.

泡沫沥青发泡性能的评价指标：

Evaluation index of foaming properties of foamed asphalt:

◆膨胀率：泡沫沥青的大体积／初始沥青的体积。本工程的膨胀率为20倍。

Expansion rate: the maximum volume of the foamed asphalt / the volume of the initial asphalt. The expansion rate of the project is 20 times.

◆半衰期：泡沫沥青的大体积缩减至1/2大体积时，所用的时间（秒）。本工程的半衰期为20秒。

Half life: the time (seconds) when the maximum volume of foamed asphalt is reduced to the maximum volume of 1/2. The half-life of the project is 20 seconds.

膨胀率越大、半衰期越长的泡沫沥青拌和效果越好，泡沫沥青混合料的质量越好。

The greater the expansion rate and the longer the half life, the better the mixing effect of the foamed asphalt, the better the quality of the foamed asphalt mixture.

影响沥青发泡特性的主要因素：

Main factors affecting asphalt foaming characteristics:

◆沥青的品种、组分及等级

◆ type, composition and grade of asphalt

◆沥青发泡时的温度

◆ temperature during asphalt foaming

◆发泡用水量

◆ foaming water consumption

◆沥青和水的喷射压力

◆ spray pressure of asphalt and water

◆加入的表面活性物（发泡剂）

◆ added surfactant (foaming agent)