Study on IR Curve Fitting on the Modified Mechanism of Portland Cement

Modified Portland cement prepared by adding phosphoaluminate cement clinker into Portland cement has excellent mechanical performance.-OH asymmetric stretching vibration bands in IR spectra were studied by the method of curve fitting and the comparison was conducted between the modified cement and grade 42.5 Portland cement.Finally the modification mechanism of phosphorus aluminate cement to Portland cement was analysied.The results indicate the modified Portland cement paste,as well as that of Portland cement,have five kinds of states,including Ca-OH,Si(P)-OH,Al-OH/AFt crystal water,Hydrogen bonds in water and coordinated water.But compared Portland cement,water,which exist in OH combined with Si and Al,in the paste of modified cement are more and which exist in OH combined with Ca,hydrogen bonds as well as coordinated water are smaller than those of Portland cement.It therefore shows excellent mechanical properties compared with Portland cement.