南沙港淤泥固化前后物理力学性能和微观结构变化

为找出广州南沙港某油罐仓储区工程淤泥加固时固化剂的最优配比,取该工程区典型淤泥,以水泥、石灰、石膏、水玻璃和减水剂作为固化剂,对淤泥进行加固试验研究,以无侧限抗压强度来检验加固效果,找到最佳的固化剂掺量,并进行固化淤泥与原状淤泥力学性能和微观结构变化的对比研究。试验结果表明,水泥、减水剂、水玻璃、石膏和石灰掺量分别为20%,1.5%,10%,6%和16%时淤泥的固化效果最佳;影响固化土强度的5个因素中,水泥掺量影响最大,石膏掺量影响最小。相比原状土样,最优配比固化淤泥试样的渗透系数和孔隙率分别减小81.0%和59.8%,三轴不固结不排水试验的黏聚力和内摩擦角分别是原状土样的3.8和4.9倍,固化淤泥的物理力学性能得到明显改善。

Physico-mechanical properties and changes in microstructure of silt before and after solidification in Nansha port

In order to find out the best additive portion of soft foundation treatment for a petroleum storage project located in Guangzhou Nansha harbor area, the typical soft sludge was selected and solidified experiment was conducted with the additive agent of cement, lime, gypsum, sodium silicate and water-reducer, and the treatment result and the best additive portion were got, the changes of the mechanical properties and microstructure of the soft sludge before and after consolidated were compared and studied based on the unconfined compressive strength. Test results show that 20%, 1.5%, 10%, 6% and 16% of cement, lime, gypsum sodium silicate and water-reducer are the best proportion, and among these 5 factors affecting the strength of the solidified soft sludge, the cement addition has become a most important influence factor and the gypsum addition is the minimum. Comparing with unconsolidated sludge soft sample, the penetration coefficients and void ratio of the best additive portion solidified sample are reduced by 81.0% and 59.8%, and C and φ of UU shear tests are of 3.8 and 4.9 times. The physico mechanical properties of the solidified soft sludge are enhanced obviously.