3、Space frame assembly
Use construction tower cranes to carry out vertical transportation of materials, and the rods are tied at two points, which should ensure safe lifting, stable air transportation, and slow descent; small materials such as space frame bearings, ball joints, and bolts are installed in special hanging cages for hoisting and transportation. The materials on the operating platform should be hoisted in an appropriate amount, as much as possible, and the materials should not be piled up in one place. After being hoisted to the platform, the operator should spread the materials around in time to prevent local rods from being overloaded. Deformation causes the platform to sink, causing danger. The procedure for space frame assembly is: install the lower chord plane space frame → install the upper chord inverted triangular space frame→ install the lower chord regular triangular space frame → adjust and fasten.
3.1、Install the lower string plane space frame
(1) Assemble from the space frame at the end, place the supports on both sides of the end on the starting point, pay attention that the center of the support should be aligned with the cross line at the starting point, measure the elevation with a level, adjust it if there is an error, and then Draw a through line between the A and B shafts as the alignment of the middle ball node and the rod at the installation end. Next, install the temporary support frame according to the space frame’s vertical bottom string ball node spacing. The height of the temporary support frame should be strictly controlled according to the space frame slope to ensure the parallelism of the bottom string balls, and ensure that the space frame at the support frame is evenly stressed and the rods The force is consistent to prevent uneven force and partial support frame sinking.
(2) Install the first (end) lower chord ball and lower chord (note that the length of the high-strength bolts at both ends of all rods extending into the ball joint should be 1.1d to 1.2d (d is the diameter of the bolt), and the bolt ball must not be Penetration) to form a longitudinal plane space frame; then install the first (end) web bar and the upper string ball, after the small unit of one ball and two web bar is in place, screw the web bar into the lower string ball for fixation; then install The first chord (end) is the upper chord, and the depth of the upper chord screwed into the bolt ball should be adjusted to control the size of the space frame and adjust the lower deflection of the space frame.
(3) After the first installation is completed, check the space frame size, the longitudinal size of the space frame and the height of the space frame. If there is any deviation, you can adjust the height of the temporary support frame to correct it.
3.2、Install the upper chord inverted triangular space frame
(1) Start continuous assembly from the 2nd chord, install 1 lower chord ball and 1 lower chord rod from the support, and install 1 horizontal lower chord rod correspondingly from the 1st chord (end) of the lower chord to form the 1st square space frame.
(2) Install the inverted triangular cone, assemble the first upper string ball node from the support on the adjacent operating platform and the corresponding two webs of the current one and one web of the previous one. Together, form a triangular cone, and then use the rope to lift the triangular cone upwards. When the height of the installed lower string ball is reached, compare the design drawings and screw the web bar of the first bar and the web bar near the support of this bar into their respective In the hole of the lower string ball belonging to, fasten, and the web bar of this truss away from the support is suspended in the air temporarily.
(3) Then install the bottom string ball and the longitudinal bottom string rod. One end of the rod is screwed into the screw hole of the installed bottom string ball, and the other end is screwed into the newly installed bottom string ball. At the same time, the original suspended web rod and the newly installed bottom string ball connected.
(4) Then install the horizontal lower chord between the front and the main chord to become the second space frame closure of the lower chord.
(5) Then install the upper chord between the support and the first inverted triangular cone.
(6) Continue to install the inverted triangular cone with one ball and three rods in the same process. During installation, every time a set of inverted triangular cones is installed, a vertical upper chord rod is installed synchronously to connect the inverted triangular cones into a whole, so that the upper chords of the space frame also form a closed square space frame.
(7) After gradually installing to the support at the other end, check and adjust the longitudinal dimension and deflection of the space frame.
3.3、Install lower chord triangular space frame
(1) After installing this inverted triangular pyramid space frame, start to install the regular triangular pyramid space frame.
(2) Install the horizontal upper chord between the front pole and the main pole, so that the ball and the pole form a closed square space frame, install the remaining web pole of the front pole, place it in place with a single pole, screw in and fasten it, and then install the main pole 1 web rod of the tree, the bottom string ball and the top string ball are screwed into both sides to complete a set of regular triangular pyramid space frame.
(3) After each regular triangular pyramid is completed, check the size error of the square space frame on the upper chord, adjust and tighten the bolts.