Accidents of civil engineering happen a lot during construction and operation.The traditional method of monitoring and pre-warning cannot get feedback in time and directly;it often misses the best opportunity to prevent disasters.In order to solve this problem

this paper presents a new monitoring and pre-warning method of risk visualization

which receives measuring information with sensors

analyzes the information with microcomputers to get the risk level of the project

and then changes the color of LED（Light-Emitting Diode）to represent the pre-warning information and ensure the safety of engineering.This paper introduces the concept

the basic principle of risk visualization

and its application in each areas of civil engineering.A prototype of risk visualization system has been developed

and indoor demonstration has been performed.