Application and development of the grid steel structure report

The grid structure of the spatial structure of the most widely used type, medium and small span are applicable. steel structure called the grid structure that is flat grid. Surface grid that reticulated shells. The three types of single, double and multi-layer network structure. The most commonly used is a double, rarely used monolayer, when the span is large (e.g. 100 meters) can be used three grids. The grid structure has unique advantages over other spatial structure, the first in our applications, so far applications are most widely used up to the fast pace, large scale, the sheer number, called the world grid large country. The grid structure development began in the 1960s, first built in Shanghai a leaf node grid, followed by a 1965 study successfully welded hollow spherical joints grid. Welded hollow spherical joints is simple, has many advantages, grid structure soon in our country to promote them bolted spherical joints grid over time. Both node has its own advantages, neck and neck have been widely adopted.

Grid provisions in China's "network structure design and construction rules in the form of 13, depending on the span, flat shape and purpose and the use of different forms of grid. Square or rectangular plane is the most commonly used is a positive square pyramid, is put to find time PYRAMIDIC and the diagonal square pyramid grid, sometimes two of orthogonal and two the orthogonal diagonal mesh frame; circular or hexagonal plane, commonly used three-way triangular pyramid and taking the time to triangular pyramid grid. The other two diagonal Bias, checkerboard, star PYRAMIDIC, honeycomb grid is not commonly used on the plane for the long and narrow one-way mansard more economical and reasonable.

In addition to the double-grid three grid more applications in large span. Three grid stiffness segment uniform internal force, and reduce the internal force peak, short rod and mesh the advantages of small capital airport hangar, Changsha Huanghua Airport hangar and Guixi Power Plant dry coal shed three-tier grid. The double grid winding instead of the concrete slab, and the combination node instead of winding node is a combination of network structure, and many buildings have been built in our country.

First is the design of the grid in Wangjiagongcheng grid is calculated according to the span size, grid type and Engineering require precise calculation method (the space trusses displacement method) or the simplified calculation method (such as differential method, sandwich plate method imaginary moment method) to calculate the internal forces and displacements simplified calculation method has also published some form for the look-up table to calculate. Later, the rapid development due to a computer, the Computer technical strength and growth, basically accurate method without approximation. Computer not only theoretical analysis but also to optimize and construction plans drawn. Computer software applications has become popular in the various units of the country. Zhejiang University, Tongji University, Tianjin University, Shanghai Jiaotong University, the best software today also unveiled.

With good design after grid construction is very important. The grid construction combined with China's specific situation many earth approach, as well Tuyangjiehe way, bolt ball node grid use more high-altitude bulk method (full house steel structure node grid of solder balls to use more artificial winch pull lever lifting the overall law, small and medium-sized span of 2 to 4 uprooted rod can be used, a larger span of 13 uprooted lever can be used, the Shanghai Hongkou Stadium 17 uprooted rod, while up to 27 uprooted Terra-Cotta Warrior Museum II Museum rod are using artificial twist, these indigenous methods both effort and smooth, low-cost construction, in line with China's national conditions. Other lifting methods of summed up over the years more mature 7 has adopted specification: altitude bulk method - small fight unit or rod assembled directly at high altitude; slitting or block installation method - grid divided into the strip unit or block unit integrally connected at high altitude; sliding method - a single slip gradually accumulated slip and carriage law; overall lifting method - single or uprooted rod lifting, can also be used a one or more cranes lifting; the overall upgrade method - lifting equipment installed in a structure to enhance grid, while improving the grid can also be conducting column slipform construction, the structure can be used as the operating platform; overall jacking Law; overall fold l law - the like the internationally famous climb up to the dome Act (Pantadome).

Grid ability to promote the use of mainly rely on what node in the grid structure engineering grid node is the most critical component. Of the most common node is welded hollow spherical joints and bolted spherical joints, other board node specification has been satisfied with, but not actual engineering using; intersecting node in the grid is not very suitable, suitable for triangle space truss. China has built the grid of the various forms of thousands of seats, many worth mentioning the typical Wangjiagongcheng, industrial plants, aircraft hangars, terminal, railway stations and other types of representative works include: the FAW the Volkswagen PQ35 project final assembly workshop Yunnan Yuxi Cigarette Factory, the capital airport bit steel structure, Capital Airport Terminal T3A, Shenyang Expo Center are more successful grid structure engineering, and to some extent, promote technological progress of China's grid structure engineering .

Fireproof coatings use of countermeasures

http://structureworkshop.blogspot.com/2012/12/fireproof-coatings-use-of.html