免费看无码自慰一区二区,女同另类国产精品视频,天堂草原电视剧在线观看免费,日韩成人片免费永久在线观看网站,欧美国产精品一区久久,欧美一区二区性爱视频,一本无码aⅴ久久久国产,亚洲丁香五月婷婷

The plastic track is composed of polyurethane prepolymer, mixed polyether, rubber, EPDM particles or polyurethane particles, pigments, additives and fillers. The plastic track has the characteristics of good flatness, high compressive strength, moderate hardness and elasticity, and stable physical fitness, which is conducive to the performance of athletes, improve sports performance and reduce sports injuries. At the same time, the plastic track has excellent anti ultraviolet, anti-aging and corrosion resistance functions, and is recognized as an ideal sports ground in the world.

Advantages

1. Low requirements for foundation flatness.

2. The cost is between mixed plastic runway and breathable plastic runway.

3. Low requirements for basic underground water pipeline.

4. More simply, it has been accepted by the World Athletics Federation.

Deficiency

1. The composite runway has poor elasticity.

2. During construction in humid environment, the water vapor of cement concrete foundation may cause plastic foaming and delamination, while asphalt concrete will not cause this problem.

Source: Jiangmen engineering plastics http://www.wcyxs8888.com/