“倍数表达” 属于数词用法。用于比较句只是其中一个用法。

The box is three times the size of that one. （倍数用于名词尺寸大小）

The box is three times as big as that one.（倍数用于形容词比较）

This figure is five times the original estimate.  

这个数据是最初估算的5倍。

来自柯林斯例句

This figure is five times the original estimate.  

这个数据是最初估算的5倍。

来自柯林斯例句

 The soil contains 30 times the acceptable level of radioactivity.  

这片土壤受到了高于标准30倍的辐射。

来自《简明英汉词典》