A detailed method is introduced
The construction methods and technical measures2.1 construction processTo measure the slope, slope protection, Boulder rolling, processing or drainage construction, earthwork excavation, slope protection, inverted arch and side wall foundation construction, liming cave mould, steel banding, liming mould, pouring concrete, concrete outside the health to release, waterproof layer construction, backfilling and protection engineering construction.2.2 construction methods1) Myongdong and a complete portal excavation, excavation with full width transverse dredging method once formed, the first slopes, put the line before the excavation, then drain.2) with earthwork excavating, the small rock blasting method, drill hole, millisecond electric detonator, mucking loaders, dump truck transport, blasting near the slopes, with smooth blasting, in order to ensure the stability of slope. Excavation from top to bottom, side of the construction side slope excavation and slope into the face of the protection works.3) the first tunnel excavation after 10 ~ 20m, and then open cut tunnel lining. When construction, pay attention to Myeongdong and at the joint of the dark hole, from the inside out.4, before entering the cave, complete all slope reinforcement and protection measures.
5) the construction of open cut tunnel reinforced concrete structure construction is divided into two parts: first, the construction of inverted arch and wall foundation of reinforced concrete, to be part of the concrete reaches certain strength, stripping, cutting hair construction joints, and construction of the upper side wall and arch of reinforced concrete. The inverted arch and wall part of the composite steel formwork, artificial pouring, side wall and arch concrete construction formwork for the internal mold, and molded with combined steel formwork, formwork and external bracing to ensure stable, symmetrical pouring concrete, steel processing plant in processing molding, binding site. The concrete is produced by the automatic metering concrete mixing station, the concrete transport vehicle transportation, the concrete pump into the mold, the insertion type tamping device is compacted, and the arch wall concrete is completed once.6) water proof construction, laying waterproof layer, tunnel construction on the surface of concrete repair chisel flat uneven place to prevent damage of waterproof board. The weld quality of the waterproof board shall meet the requirements. If there is any defect, corrective action must be taken to meet the requirements.7) arch backfilling: Myeongdong vault above maximum backfill height 2m, compaction degree '93% fill in the top-level clay layer of water, the backfill surface of turf.Back fill both sides of the symmetry at the same time, the bottom of the wall filled with 0.5m ~ 1m thick gravel and compacted, and then the use of artificial layered backfill, layer by layer compaction. Careful protection of the waterproof layer during backfilling is not destroyed.The water layer of clay and the side, the slope of the lap is good, close to prevent surface water leakage.
1 overall construction planUsing the new Austrian tunneling method, the construction principle is "less disturbance, early spray anchor, ground measurement, tight closure". The rock excavation method of construction; rock class micro bench excavation, pre splitting blasting; IV surrounding rock by construction method (Section IV surrounding rock under the partial, the construction step method), smooth blasting technique; fault fracture zone by middle wall construction method.The ballast is unloaded by the side unloading loader.Two lining the rail trolley, concrete mixing truck to transport concrete, pumping concrete, lining after decoration engineering construction.It is necessary to strengthen the geological prediction in the fault fracture zone and water rich zone, and provide the basis for the construction.
