On Optimized Construction Technology Of Waterproofing Concrete In Ran Jiaba Tunnel

Aiming at the tunnel construction method and waterproofing criterion in our country, the mix-proportion and construction technology of waterproofing concrete were optimized in present paper, combining with the research project demands of Ran Jiaba tunnel waterproof or drainage in Chongqing. The theoretic gist of tunnel waterproofing technology was discussed deeply, the waterproof methods , integer waterproofing ways associated part waterproofing ways, economy and rationality of waterproofing system , etc were also analyzed and summarized, which is the basis of future tunnel waterproofing or drainage design.Basing on the reconnaissance and project data, the hydrometeorology and geology of tunnel building site which are the basic data to ensure the penetrate pressure were investigated deeply, and tunnel waterproofing scheme were confirmed, according to practice requests.The mix proportion and construction scheme of waterproofing concrete were carried through optimal design, in terms of requests of project design for secondary line and optimal waterproofing schemes, raw materials, and construction cast. The site experimentations indicate that W/C ratio is reduced, workability is increased, and interior capillaries are decreased, by using of pumping agents in concrete. Adding fly ash in concrete can modify workability of mixture, reduce heat of hydration, thin the structure of pores and enhance long-term strength. The use of expansion agents can reduce or avoid volume shrinkage of concrete, improve crack resistance property of concrete, especially adding FDN-P compound agent, which is economical, can more effectively increase self waterproofing capacity of concrete, consequently comprehensively enhance self anti-penetration of concrete.Basing on practice measures of underground tunnel construction joints and function mechanism of water-sealing stripes, the different waterproofing measures were took in tunnel construction joints and areas between joints, which is in the person of waterproofing or drainage principle-main in drainage, waterproofing ways associated drainage. And in this foundation, water-sealing stripes were designed and adopted, which ensured the effect of construction joints and optimize the schemes of waterproofing concrete. The local water-sealing stripes were carried in site experiments, the results show that water-sealing stripes bring into play as long as water-sealing...