弱化作用 meaning in English

attenuation

Some retarders permanently weaken the concrete .
某些缓凝剂对混凝土起长期的弱化作用。
Due to hazard zone with many migrations , disaster of daheba landslide is serious , so , prevention and treatment to daheba landslide is very urgent . 2 . based on gensis analyse of landslide , human ' s engineering activity and water is main factor of landslide
2 .大河坝滑坡灾害性有其特殊性，通过分析自然条件、地质环境及人类工程活动影响的分析，并进行极限平衡定性分析，大河坝滑坡的产生其主要因素是人类工程活动加载及水对岩土体的弱化作用。