1. Tennis Hall Project Overview
This project is a steel structure space frame of a tennis hall. The main structure is a bolt ball steel space frame, a square quadrangular pyramid type, and the support conditions are the peripheral column point support. The length and width of the steel space frame are 100.5mX91.5m, the projected area is 9196m2, and the maximum thickness of the space frame is 4.05m. The facade is wavy, and the top elevation of the space frame is 20m. In the middle of the stadium is a tennis court, surrounded by spectator seats. The amount of steel used is about 450 tons.
Due to the tight construction period of this space tennis center project, the erection of full scaffolding has a great impact on the construction progress of the project. Therefore, it is considered to adopt the high-altitude bulk method for construction as much as possible, so the project quality and safety production requirements are very high. The installation sequence of the space is carried out from south to north. It is required that the civil construction should reserve a mechanical access channel in the north, and harden the ground in the pavilion to ensure that the car is hoisted on the construction site. Therefore, the construction and deployment principles of the steel structure of this project are (1) overall consideration and reasonable overlap in process arrangement; (2) optimization and balanced allocation in terms of resource assurance; (3) advanced, feasible, economical, and applicable process selection; (4) Comprehensive coordination and careful service in construction management.
2. space frame construction
2.1 Preparation for space frame construction
The construction of the steel space structure project must go through two stages of factory production and on-site installation. It is of great significance to do a good job in the inspection and selection of the steel structure manufacturing unit and the installation unit, which is of great significance to ensure the quality and progress of the steel structure space project.
2.2 space installation sequence and quality control points
(1) Inspection of the process flow: pay-off and inspection → install the lower chord plane space → install the upper chord inverted triangular space → install the lower chord sine triangular space → adjust and tighten → support welding and acceptance.
(2) Key points of quality control for the installation of the lower chord plane space: ① After the support between the first spans is installed, align the axis and center line of the column top, check the elevation with a level, and control the error within the specification requirements. . ②Install the lower chord ball and rod between the first span to form a longitudinal plane space. ③Check the arranged temporary fulcrum to ensure the parallelism of the lower string ball. ④Check the installation quality of the web rod and the upper string ball between the first span, the small unit of one ball and two web rods in place, and the screwing of the lower string ball. ⑤ Install the top chord between the first span to control the size of the space. Note that the pressing depth affects the lower deflection of the entire space, and control and check the size. The height of the temporary fulcrum can be adjusted to control the size of the space.
(3)Quality control points for installing the upper chord inverted triangular space frame: ①The second unit of the space frame is assembled by the continuous installation method. ②Install a lower chord from the support, check the quality of the thread, clean the screw holes and screws, and screw them in after cleaning. At the same time, install a lower chord from the first span of the lower chord to form the first square space frame The first node ball is enclosed, and the first space frame of the lower chord is closed. ③ Install the inverted triangular cone and hoist the small unit with one ball and three rods into the site. Support the lower string ball with the two inclined rods, and tighten the upper string rod separately above, so that the upper string rod is gradually approached the installed string ball and screwed in. ④ Then screw the oblique rod into the lower string ball, tighten it, and the other oblique rod can be temporarily empty. ⑤ Continue to install the lower chord ball and the rod, screw one rod into the original lower chord ball screw hole, one ball is connected with the other inclined rod at the front of the installation and screwed in, and the horizontal lower chord rod is installed in place, and the two ends are screwed into the ball to form a lower chord. The second space frame of balls is closed. ⑥Continue to install a ball and three-bar inverted triangle according to the above process, and install a longitudinal upper chord between the two chamfered cone inverted bodies to connect them into one. Step by step, for each set of inverted triangular cones, install a longitudinal upper chord rod, and the two ends of the upper chord rod are screwed in with bolts so that the upper chord of the space frame also forms a closed square space frame. ⑦ After being gradually installed on the support, a series of vertical inverted triangular pyramid space frames are formed. Check the longitudinal dimension, check the deflection of the space frame, and check the force of each fulcrum.
(4) Key points for quality control of the installation of the lower sine triangular mesh: ① After the space frame is installed with the inverted triangular pyramid, the installation of the regular triangular mesh begins. ②Install the lower chord ball and rod in the form of one ball and one rod, and screw one rod into the screw hole of the support. ③ Install the horizontal lower chord, so that the ball and the rod form a closed square, and check the size. It can also be in the form of one ball and two shots. ④Install one side of the oblique abdominal rod, put the single rod in place, screw it in, and it is convenient to control the sag height of the space frame. ⑤ Continue to install the other side of the oblique belly rod, screw in the lower chord ball and the upper chord ball on both sides to complete a set of regular triangular pyramid space frames. Install gradually to one side until the support is reached. ⑥ After each completion of a regular triangular cone, install and check the size error of the upper chord square space frame, adjust it gradually, and tighten the bolts. When installing the regular triangular pyramid mesh, always pay attention to the stress on the temporary fulcrum.
(5) The key points of the installation, adjustment, and tightening quality control of the rods: ① Measure and check the installation quality of the members at any time when the frame is installed. Check the size and diagonal of the lower chord space frame, check the size and diagonal of the upper chord space frame, and check the longitudinal length, transverse length and space frame sag of the space frame. Make adjustments before each temporary fulcrum is removed. ②When the frame is installed, measure and check the installation quality of the space frame members at any time. Check the size and diagonal of the lower chord, check the size and diagonal of the upper chord , and check the longitudinal length, transverse length and space frame sag of the modular. Make adjustments before each temporary fulcrum is removed. ③ During the installation process of the space frame, the subsidence of each temporary fulcrum should be checked at any time. If there is a drop, reinforce it in time to prevent the phenomenon from falling.
The space frame project of the tennis center adopts an integral segmented roof, which has a large structural span and a tight construction period, which brings a lot of difficulties to the construction. Comprehensive and systematic research and demonstration of the installation technology of the space frame roof has been carried out, which provides a precedent for the installation of similar projects in China. At the same time, the project is completed on time with high quality and high efficiency, which fully proves the technical strength and management level in similar projects.