New technology and loading tests of horizontal jet grouting arch

Based on the equipment performance and construction problems of horizontal jet grouting technique in China, a new construction method for rotary high pressure horizontal jet grouting and new equipments are developed based on field technology and loading tests by China Jingye Engineering Corporation Limited. In field tests, the seal equipment achieves good results. The excavation shows that jet grouting piles lap joints are close and have no cracks after 28 days' maintenance; and the construction effect is good. After cleaning out the overlaying soil, it can be seen that the texture of the jet grouting piles is uniform, the lateral and vertical lap joints are good, and the occlusion size is about 0.2 m. The compressive strength is of returning fluid sample blocks is about 60% of coring blocks. Based on the full scale tests, the Q-s curves are relatively stable. The cracks occur and are constantly extended, resulting in collapse of the jet grouting arch by cracks perforated. Numerical simulations and tests show that vertical and horizontal displacements of the jet grouting arch increase with the increase of load, and the maximum displacements occur at vault.