Experimental Investigation Of Grouting Into Rich Water Sand Stratum

Grouting has been widely used construction engineering, the engineersaccumulated rich experience in grouting construction, various grouting methods andcorresponding grouting materials has been developed directed against differentgeological conditions and construction environment. But theoretical study andexperimental study on grouting into complex stratum and rich water sand stratum stillnot enough. In many cases, engineers have to operate depending on their experience,this may lead to material waste and poor result, even cause project accidents.In order to research on grouting into rich water sand stratum, the authordeveloped a water plugging grouting test device and a reinforcement grouting testequipment, and conducted six grouting tests respectively. the main research contentsare as follows:1. Analyzes the groutability of sand stratum. Decide to use phosphoricacid-sodium silicate double grouts and cement grout as the grouting materials in richwater sand stratum after consulting engineering practices.2. By conducting the experiment of gelation time of phosphoric acid-sodiumsilicate double grouts, analyzed the gelation time of the double grouts of different mixmode. Analysis the water plugging effect of the phosphoric acid-sodium silicatedouble grouts by the self developed grouting device.3. Analysis the different influence on the basic properties of cement grout ofdifferent kind of additive, and find out the optimal additive and determine its addingquantity to improve the groutability by laboratory proportioning test; Then conductedreinforcement grouting test with different grout pressure and different earth pressureby the self developed equipment; At last, analysis the reinforcement effect.4. Based on the test results above, chose the optimal ratio of the groutingmaterials and grouting parameters, applied them to a field test in Beijing subway line14and evaluated the grouting effect.