The project of this 6,000 square meters was originally negotiated on the October of 2019, after 2 months of negotiation, the order was confirmed. 20 days of manufacturing, the goods were delivered to Vietnam in January 2020.
Since the covid-19, the installation began last month, and with 30 days of installation, the warehouse was done under the guidance of Dorian engineer last week.
Hereby are some notes and FAQ about the warehouse assembly and experience about the this project.
Column bottom evaluation and vertical detection
1. The calibration of column generally include three points:plane position,elevation and verticality.
2. It is one-time alignment when the steel column is hoisted in place,and generally no plane recalibration is required.About evaluation part,since the evaluation has been accurately controlled with φ30 pre-buried”medium tendons”before hoisting,generally only the inspection needed,and no further correction is required.Therefore,steel column correction is mainly calibrate the verticality and review the elevation.
3. Column calibration work need to be performed simultaneously with the professional measure tool.Two theodolites are used to calibrate the column from vertical direction.
First step, set up the theodolite on the side of column,align the longitudinal center line with the baseline of column, then fix all the screws on the horizontal plate.
Measure the center line of pillar from top to bottom.
2*25 tons cranes(crane size determined by the different construction capacity) works parallel as flow. Steel column is hoisted by the single screw method, and manual lifting to assist if necessary. Crane routes indicated as below sketch:
Point of screw hoisting method:Hooking and rotating around the column leg in the mean time called Screw Hoisting like picture#B indicated as below. In order to improve the working efficiency,when placing the column to the construction sit, three points of binding point,center point of column foot and center point of foundation base should be centered around the crane stopping point; Distance of stopping point to binding point is on on arc with a radius.
Use a crane to place the purlins between the beams. The purlins are perpendicular to the roof ridges to ensure that the roof purlins are in a plane. Purlins are aligned with holes in the beam, fixing bolts. If the hole fixed bolt. If the holes on one of the beams are not aligned with the holes on the purlin, you can gently pull the beam with a rope until the holes on both sides are aligned.
This process is also the process of secondary correction of the steel frame. If the wind at the installation site is greater than Grade 5, the installation cannot be performed, otherwise accuracy will be affected and worker safety cannot be guaranteed.
Roof and wall panel installation
Plate type selection: According to the roof slope and drainage, choose different types of steel plates. Large slope and large displacement, generally use 820 type, 760 type. Type 760 corrugation is larger than type 820, which can better meet the requirements of rapid drainage.
If there is no drainage and other special needs, for the convenience of transportation, color steel plates are usually 840 type and 900 type. The sandwich panel adopts 950 type, 960 type and 980 type. If have special needs, change the version according to specific conditions. Panels should be scattered and stacked for easy handling. When handling, handle it gently to prevent deformation, breakage and rain leakage.
Usually the roof panel is installed first, followed by the wall panel. The panels are connected with self-tapping screws and wall-roof purlins. When tapping the self-tapping screws, use ink lines to align each row of nails.