主动侧 meaning in Chinese

drive side
driving side
master end

Then it follows that under stable seepage the water pressure outside the foundation pit is reduced with a little change of the total horizontal pressure , while the water pressure inside the foundation pit is increased with a great change of the total horizontal pressure
针对这一情况，利用流网分析了在基坑周围存在稳定渗流时支护结构上水土压力的变化，并对其变化进行了分析与对比计算，得出绕支护结构的稳定渗流减小了主动侧的水压力，但总的水平压力变化不大；被动侧的水压力有所增加，但总的水平压力减小较多。