Study On Construction Technology And Empirical Of Large-diameter And Long-distance Water-transport Steel Pipe As A Whole Immersed Pipe

In the field of urban pipeline construction,some facilities need to cross rivers,roads,railways,bridges,etc.,which brings some difficulties to the construction.This paper combines the relocation of water intake structures of Rongqi and Guizhou Waterworks and the Xingtan section of the original water pipeline project.Large-diameter long-distance water conveyance steel pipe is used to study the construction process of submerged pipe under the river.The thesis adopts PDCA cycle,system theory,numerical statistics,finite element and drone photography technology to the overall lifting technology,Structural system,resource allocation,schedule control,quality control,safety management,environmental protection and economic benefits.The research results show that:(1)In terms of technology,the large-diameter long-distance water conveyance steel pipe integral hoisting and immersed pipe construction technology principle is used as "integrally welded steel pipes on the embankment,hoisting and launching as a whole",fixed lifting points,lifting in steps,each step Lifting height is controlled in the range of 20 cm ? 25 cm,and the circumferential deformation rate of the steel pipe is controlled in the range of 1% ? 2%,which can prevent the stress concentration of the welded steel pipe,and can effectively control the welding seam and the base material from being pulled when the whole zigzag steel pipe is hoisted into the water Cracking,buckling or flexing;(2)In terms of resource allocation,the application of large-diameter long-distance water pipe integral hoisting and immersed tube construction technology in multiple ship hoisting and integral hoisting and immersed tube construction technology is adopted,and the cost margin of large crane ships 9.74%,is the key equipment to implement the cost control of the overall hoisting;(3)In terms of schedule control,through network optimization,the overall welding of the steel pipe is synchronized with the underwater trench excavation,and the key of the overall hoisting sinking and solid pipe back filling The actual progress of the pipeline operation of the construction process is 20d-30 d ahead of the contract progress,and the key construction period is saved by 25%;(4)In terms of quality control,combined with PDCA cycle quality management The system and quality QC activities were carried out to effectively solve the key problems of the overall welding of steel pipes and the hoop deformation rate of the overall hoisting steel pipes.The qualified rate of the pressure water test after the steel pipe hoisting installation is in place reaches 100%,which meets the design and specification requirements;(5)The large-diameter long-distance water conveying steel pipe integral hoisting and immersed pipe construction technology has been proved by engineering practice to save actual cost by about 1% of the construction budget cost,and has significant economic and social benefits.