Concerning the rare study on mechanical properties of phosphogypsum

the relationship of strength with confining pressure is investigated by the triaxial compression experiments with high confining pressure. From the experiment results

it is found that the strength will increase with the increasingly confining pressure and the tendency is very obvious. It is dangerous to use the strength parameters obtained from the conventional triaxial compression experiments to analyze the stability of high phosphogypsum dam. Taking a high phosphogypsum dam for example

the stability of the dam is analyzed

And the results indicate that the safety factor would obviously decrease if the strength reduction of phosphogypsum in high confining pressure were taken into account. A conclusion is drawn that the strength reduction of phosphogypsum in high confining pressure is evident

and it is necessary to consider the strength reduction of phosphogypsum when analyzing the stability of high strength reduction of phosphogypsum dam.