Study On The Cement-soil Mixing Piles And It Detection Methods Of Soft Ground In Pearl River Delta

Pearl River Delta Economic Zone is located in South Central Guangdong Province, near the South China Sea, adjacent to Hong Kong and Macao, administrative jurisdiction over domains including Guangzhou, Shenzhen, Zhuhai, Dongguan, Zhongshan, Jiangmen, Foshan, Hui District, Hui Yang District, Hui East County, Boluo, Zhaoqing City, Gaoyao, the four cities, the total land area of 41698km2.Distribution of sizes, from the soft soil, the Pearl River Delta economic zone, plain were 7969.28,6554.88 km2, each corresponding total land area of 18.98% and 58.11%. Because of its unique geological, geographical and thus formed into a significant regional, makes the Pearl River Delta reported in the soft soil into the country over the project met the softest of soft soil with low bearing capacity, deformation under load after the big time effects were significant and strong interaction with the buildings and other features.Pearl River Delta now mainly drainage consolidation soft (including preloading method or vacuum preloading method), cement mixing method and the small number of works dealing with soft composite foundation.For cement deep mixing method, the soft soil organic matter would obviously affect the strength of cement. Also, the present cement mixing pile on the detection methods do not improve and standardize the testing did not recommend a unified approach and evaluation indicators, is not conducive to engineering applications. Therefore, combination of practical experience in engineering, the first in-depth analysis of organic matter content on soil cement mixing pile strength, pointed out the impact of organic matter in soil strength of the main components of cement and cement from the cement hydration process and the structure of soil micro-perspective of its impact mechanism, and proposed project feasible approach.According to the characteristics of soil cement mixing pile and engineering practice, comprehensive assessment of various current methods of soil cement mixing pile test the advantages and disadvantages. Should be detected for the cement mixing pile shaft strength, uniformity and length of pile to be fully evaluate mixing quality, this thesis proposes standard penetration test or coring test supplemented by laboratory strength testing as cement mixing pile test specification method; the same time reasonable response to the real shaft strength, this paper suggested that in future core samples should standardize sampling, production, conservation and make a uniform intensity value technical requirements; of combined engineering experience, the more reasonable given core sample test methods. Finally, the author of a combination of cement mixing pile test engineering example, shows that the thesis proposal is reasonable.