中文摘要：

对用户在突发事件情境下的行为、构成和各类用户特征进行分析，结果显示有关突发事件的提问与回答几乎同步，当天提问当天即有人回答；突发事件吸引了大量匿名用户和沉寂用户参与在线问答，活跃用户在回答问题满意度和参与回答数量上都远远高于前两类用户；如果用户为权威用户，其回答被采纳率更高。最后提出一些改善突发事件网络沟通效果的建议。

英文摘要：

This paper analyzes the user types and their behavior in Q＆A community at the time of public emergency. The results show that the questions and answerers are almost synchronous appeared on the Q＆A community during the public emergency. Someone just posted the question on the community. They got the answers at the same day. Anti the publie emergency can attract a lot of anonymous users and dormancy users to participate in Q＆A community. The satisfaction rate and answer quantity of active users are obviously higher than other users. The adopted rate of answers from authority is higher than others. At last, some suggestions are proposed.