The China steel structure components production of steel and steel castings varieties, specifications, performance

Quality of imported steel products should meet the requirements of the standards of design and contract provisions. Variety of welding materials, specifications, and performance should be consistent with the current national standards and design requirements. Steel connection connected with high strength large hexagon head bolts Vice torsional shear type high strength bolts connecting Vice steel grid with a high-strength bolts, common bolts, rivets, self-tapping screws, pop rivets, Nailing, riveting bolt (mechanical type and the formula dosage forms), foot riveting bolt fastening standard parts and nuts, washers and other standard accessories, varieties, specifications, performance should be consistent with the current national standards and design requirements. High strength large hexagon head bolts connection deputy China steel structure and torsional shear type high strength bolts connecting the factory should be, respectively, with the box with torque coefficient and fastening axial force (pre-tension) inspection reports.

The welders must, pass an examination and obtain a certificate of competency. The permittee the welder must in passing the examination of the project and its scope of accreditation welding. Design requirements for full penetration of the two weld ultrasonic inspection for internal defects inspection, ultrasonic inspection can not make judgments on the defects, should be used ray detection the internal defect classification and testing methods should be consistent with the current national standard "ultrasonic testing of steel weld by hand methods and classification of testing results Act "GB1135" steel melt welded butt joints radiographic inspection and classification of "GB3323 requirement.

Steel columns, steel girder webs material should pay attention to the cross-sectional dimensions of change, allowance should be left at both ends the beam weld using automatic submerged arc welding, welding sequence according to the welding process requirements of the order. Hole, all connecting plate, gusset plate must be paired drilling hole on accuracy should meet the specification requirements. The anticorrosion coating: shot blasting reach ST2 level. The surface of the component should not China steel structure mistaken coated friction connection (especially face), drain coating, the coating should not be peeling back to rust. The coating should be uniform, no obvious creasing flow fall, such as pinholes and bubbles. Steel structure components factory inspection and No. No. generally marked the axis of the column number, overweight super long the components sometimes also marked the position of the center of gravity of the weight and lifting. The difference of the light steel and heavy steel truss steel structure construction process

China steel structure the altitude assembly method according to the structure type and construction conditions

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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

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Rise steel engineering cranes installed

Rise steel major mechanical installation of tower cranes. The selection should be based on the structure of planar geometry and dimensions, components, weight, etc.. Tower crane choose the general case, as far as possible outside with cranes, easy disassembly. Elected tower crane attached to the outer, Taki optional in the basement or another Taki; elected with climbing tower, tower cranes generally located at the elevator shaft. The position and performance of the choice of the position and performance of the tower crane tower crane should be able to meet the following requirements:
1) To make the length of the arm has enough surface coverage (buildings);
2) have sufficient crane capacity, to meet the requirements of the different location component lifting weight;
3) tower crane wire rope capacity to meet the requirements of the lifting height and lifting capacity; the steel engineering  speed have the grades to meet installation requires;

4) multi-machine operation, should be considered: When the tower crane is horizontal arm, the arm must have enough height difference, not collision should be adequate safety distance between each tower crane capable of safe operation to ensure the interoperability of the arm with the tower collision; crane jacking jacking, anchoring, or climb the tower crane, anchor or climb should consider the following questions: 1 attached to the outside of tower crane hook height shall meet the requirements of the height difference between the mounting height and tower crane, and in accordance with the tower crane tower body to allow the free height to determine the anchoring number of times. The anchor point of the tower crane should be conducive to the strengthening of steel structures, and the first to form the framework of the overall structure conducive to the curtain wall installation site. Anchorage points should be calculated. Within the climbing tower crane tower crane climb the position should meet the the tower free height and steel structure of each section of the column unit installation height requirement. Should be calculated to determine the inner climbing tower crane base with steel beam - column connection method. Climbing tower crane location within the steel structure, should climb before welding is completed, to form a whole.
Li, dismantle the tower crane Notes

1) selection of tower crane legislation to consider the construction site, the demolition of the condition of the tower crane.
2) legislation tower.steel engineering  attached tower crane in deep foundation pit slope established tower, Taki can choose according to the specific circumstances of stationary or walking base, but to consider the foundation pit slope stability, to consider the value of the maximum wheel pressure and appropriate safety measures . Within the climbing tower stand tower can be used inside buildings and steel on the platform.
3) The demolition of the tower. Externally attached tower crane, the main consideration should be given to the impact of the construction of high-rise buildings housing the demolition of the tower. Within the climbing tower demolition to rely on the the roof crane disintegration, so to be considered buried shall not be greater than the carrying capacity of the steel structure of the roof hanging maximum the wheel pressure value and track.
4) Where the legislation, dismantle the tower crane caused the pit, the additional load of the steel structure, shall require the prior structure checking.

The Comparison of the Series of the light steel structure workshop

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light steel structure CAD software functions and applications of the STS

Construction steel has the advantage of also becoming more prominent. The improvement of the quality of steel, the type of the rich, the perfection of the design theory for the development of the steel structure to lay the foundation, steel, up especially light light steel structure in China's rapid development. CAD technology development and to promote the success to complete the steel structure of the computer analysis by means of computer-aided design software to optimize the design and drawing work, on the one hand, can provide accurate calculations and drawing tools to the engineering design and improve design efficiency, safer design economic,
The other hand, will also play a significant role in promoting the further development of the steel structure. PKPM Series software is the most widely set of integrated CAD software, won the National Science and Technology Progress Award, is the only independent platform for the computer-aided design system, has now become a including architectural design, structural design, equipment design, integrated CAD system, including the multi-storey and high-rise, industrial plants and civil construction, superstructure and all kinds of basic structural design, and are to the development of integrated and intelligent direction. In this case, the China Academy of Building Research PKPMCAD engineering department from May 1995 to organize forces to study the STS steel structure CAD software to develop their own copyright, independent development of the software development to PKPMCAD Engineering Department of CFG Chinese graphics support system as a platform, to PKPM Series software PMCAD PK based. The functional requirements of the STS: the integration of CAD software, features include input from the steel building model, the cross-section optimization, structural analysis, component strength and stability checking, node design, draw until the construction details; software is applicable to multi- , high-level framework, plane frame, continuous beam, light steel portal frame, bent frame, frame - bent,
Steel truss and other structural forms; software requires simple operation, high degree of automation, user-friendly, easy to learn and use; construction drawings detailing standard drawings shall prevail, and provides convenient editing tools; software module PKPM series can interface with other modules; first STS become mainstream domestic steel CAD software, and then expand the foreign version of the specification, the international software market. 2STS software technical conditions as a professional steel structure engineering design software, must comply with the existing national norms, rules and standards. The STS software development based primarily on: the cold-formed steel design specification of the design of steel structures (GBJ17-88) (GBJ18-87) "Tall Buildings steel structure technical regulations" (JGJ99-98) "door frame light house steel structure technical regulations (CECS102: 98) light steel structure design point of order "(DBJ08-68-97) In addition, STS software follow the commonly used steel structures design manual, the provisions of the standard map. The About 3STS software function 31 model input STS model inputs can be used three-dimensional and two-dimensional methods.
The use of interactive three-dimensional modeling, guiding the user layer by layer the layout layers plane and floors, and then enter storey establish a description of the overall structure of the building data, three-dimensional modeling program has strong load statistics and conduction calculation function, in addition to the calculated weight, also done automatically calculated from the floor to the light steel structure beam, secondary beam to the main beam, main beam to the load-bearing columns, walls, and then spread from the upper structure based plus part of the applied load, can be easily established throughout the building load data. Section type of three-dimensional modeling of China and the world standard section steel composite section, welded H-beam (including a wedge-shaped cross-section), custom cross-section of the tube, box-shaped, Z-shaped, grooved steel pipe, concrete, steel reinforced cross-section in the form of concrete section, applicable to the needs of the various structural forms. Two-dimensional modeling data that can be generated by the three-dimensional modeling of the data plane frame, continuous beam data file automatically generated can also employing machine interaction to generate convenient to establish the model of the plane frame structure. Two-dimensional human-computer interaction modeling framework, portal frame, bent frame bent, continuous beams, trusses, brackets, continuous beam, a variety of structural forms of model can create various types of plane frame gantry frame, frames, trusses, curved axis also provides fast input wizard to quickly enter, you can enter a variety of roles in the form dead load, live load, wind load (can automatic layout), crane load (including pumping pillar crane load) parameters calculated and seismic.
Section type in addition to the type of cross-section of the three-dimensional modeling, two-dimensional modeling to provide the type of cold-formed steel composite section, solid web composite section, lattice composite section, composite beams, arbitrary cross-section. 32 the section optimization-section optimization is to meet the specification requirements, looking for the smallest amount of steel section size. STS software can light steel portal frame and steel truss section optimization. Gabled frames are often used in the variable cross-section member, so the constraint variables are optimized big endian, the height of the small end, the upper and lower flange width, thickness, web thickness, seven factors, STS software can be in the range of variation of the automatic or manual definition inner and quickly find the smallest cross-sectional dimension of the amount of steel. The truss optimization can be carried out lever member packet, divided into a group of the lever member has the same cross section after optimization. The optimization procedure is faster and better applicability. The 33 structure analysis and member checking STS three-dimensional, two-dimensional modeling data can interface three-dimensional analysis procedures and plane frame analysis program for structural analysis and member checking.

light steel structure Engineering and the Built Environment

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New technology -steel structure warehouse following the concrete technology

The new technology of concrete in the steel structure of the building in the traditional, most concrete technology. In the building now, concrete technology has been rare. More and more steel structure warehouse  in the construction of a wide range of application. It is understood that in summing up the past major construction process in the experiences and lessons of the technical issues,

Steel structure engineering of new materials, manufacturing process, the installation program, application technology research is currently under construction, face new challenges and new challenges, learn new construction techniques and construction methods. Steel structure housing construction technology compared with other concrete technology, design technology is not important, relatively speaking, material, theory in the design of the research phase is well engaged in the construction aspect is concerned with the concrete as well as other aspects of construction difficulty and problems encountered in a little more

Many areas to re-examine the new understanding, especially since the recent situation of many of the new steel structure warehouse in the country generally build up a lot of new construction. Toward highly integrated building technology, many industries need a lot of technical, need to combine, under the present conditions, and energy conservation, the environment, the combination of this seminar is from more structural technology, construction and installation, welding, etc. discuss, which is the most basic and fundamental essence, throughout construction science, construction environment far not to these areas, the steel structure is also combined with the built environment. The environment created, this is a big premise can not be changed.

Superfinishing surface quality influencing factors and control measures

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To detectsteel structure steelwork content and method

steel structure engineering major test content: scantlings and flatness detection; component surface defect detection; detection of the connection (welded, bolted); steel corrosion detection; the fire coating thickness detection. If the steel factory certification, or have doubts about its quality, should increase the mechanical properties of the steel test necessary to detect its chemical composition. Keywords: detection Steel Engineering steel structure used in the member is generally from steel mills mass production, and the need for compliance certification, and therefore, the strength and the chemical composition of the material is a good guarantee. Engineering detected focus quality problems generated in the installation, splicing process.
A major test content, steel works: scantlings and flatness detection; component surface defect detection; detection of the connection (welded, bolted); steel corrosion detection; the fire coating thickness detection. If the steel factory certification, or have doubts about its quality, should increase the mechanical properties of the steel test necessary to detect its chemical composition.
Second, the steel structure of the application of the test specification range of knowledge
Third, each size of the detection of the component size and flatness in the three parts of the member measured, taking the average of the three as a representative value of that size. The steel member the size of the deviation should be calculated on the basis of a predetermined size of the design drawings the the size deviation; deviation allowable value should be consistent with its product standards requirements. The beam vertical steel structureplane deformation and plane lateral deformation and the deformation of the truss members, so you want to detect both directions flatness. Deformation of the column tilt and deflection of the pillar. First visual check, anomalies or doubt on the beam, truss member fulcrum tensioning a wire or thin wire, and then measuring the vertical deviation of the points; theodolite column tilt available or lead vertical measurement. The column flexural member fulcrum tighten a wire or thin wire measuring four components detection of surface defects - Magnetic Particle Testing 1, the basic principles of magnetic particle inspection applied magnetic field on the magnetization of the workpiece (only ferromagnetic material), If there is defect, the magnetization of the workpiece after its various parts of the basic magnetic properties, while the presence of defects such as cracks, pores, or a nonmetallic substance slag, since they will be on the workpiece caused by the air gap or non-magnetic gap, so that the reluctance of the defective portion is greatly increased, the normal propagation of the magnetic lines of force in the workpiece has been the barrier, in accordance with the principles of the magnetic continuity, then the lines of magnetic force of the magnetizing field to be forced to change the path of escaping the workpiece, and the leakage magnetic field is formed in the surface of the workpiece . 2, the leakage magnetic field strength depends mainly on the degree of influence of the magnetic field strength and defects for the vertical section of the magnetizing field. The use of magnetic leakage magnetic field given show or measured, to analyze the presence or absence of defects judge its position and size. The ferromagnetic material powder is sprinkled on the workpiece, is adsorbed on a position of the leakage magnetic field of the magnetic powder, thereby forming the shape of the display defect of the magnetic marks, the detected defects can be more intuitive. This method is the application of the first and most widely destructive testing methods. Magnetic Particle general industrial pure iron or iron oxide production, is usually made of iron oxide (Fe3O4) powder of fine particles as magnetic particle. Magnetic particle fluorescent magnetic particle can be divided into two categories of non-fluorescent magnetic particle, fluorescent magnetic particle in ordinary magnetic powder particles coated with a layer of fluorescent material, so that it can emit fluorescence under UV irradiation, the main role is to enhance the contrast easy observation.
Magnetic particle testing is divided into two kinds of dry and wet: dry - the magnetic powder directly sown in the workpiece surface. For ease of powder particles to roll to the leakage magnetic field, the magnetic powder particles used in the dry assay usually larger, so the detection sensitivity is low. However, when wet with water or oil contact, the test piece, such as a higher temperature, then only the wet method is not allowed in the workpiece. Wet - magnetic particle suspended in a carrier liquid (water or kerosene, etc.) formed among the magnetic suspension is sprayed to the surface of the workpiece, when the magnetic powder by means of the good characteristics of liquid flow, and can be relatively easily to weak The leakage magnetic field while moving the wet good fluidity and can be employed than the dry method is more fine magnetic powder, so that the magnetic powder and slight leak magnetic field easier by the adsorbent, and thus a steel structure detection sensitivity of the method of the wet Bigan. 3, applied to the general magnetic particle inspection program (pretreatment - magnetization - magnetic particle - Observation records) · pretreatment component surface grease, paint and rust removed, so as not to affect the magnetic particle attached to the defect. · Magnetized choice of appropriate magnetization method and the magnetization current, power, the magnetization is performed on the member.
Vibration Stress Relief equipment on the benefits of casting, welding and other components：http://structureworkshop.blogspot.com/2012/12/vibration-stress-relief-equipment-on.html

Steel structure design to solve structural problems of common problems to solve other problems.

One, if there is a gutter, tied not to cling to the top part, or may lead to installation of the water pipe.In addition the gutter downspouts and tied and the column brace position must consider well, otherwise either tied or meet, meet braces between columns.

In two, steel structure warehouse strength bolt position must be reasonable, steel structure engineering should consider twisting device and a torque wrench construction space, not at the time of installation, because the space is too small, twisting device and a torque wrench can not in place, resulting in high strength bolts plum head to break or to tighten high strength bolts.Once met some design and the position of the sleeve will not give.Three, the party's "load data" must understand its true meaning, because the party often do not understand these things too specialized.We should accomplish transposition thinking, preliminary work done, follow-up is well developed.In four, high strength bolt connecting plate if possible, steel structure housing as a symmetrical upper and lower bolt layout method.Once in contact above 4 to below 6, shop workers take part installed do not care to be reversed, at the site of sorry to.Five, wind-resistant column and steel beam connection as a spring board connection, because the middle cross beam after the installation of deflection is bigger, Liang Ruo of bolts and wind-resistant column connection, will cause the roof.

Six, do not one-sidedly in purlin brace hole on account of "tension side pressure side," and other factors, hit the top and bottom margins ranged from the hole, because the installation is easily reversed, but the results of adverse.

In seven, a horizontal support a flower basket bolt location arrangement must be reasonable, do not stray too far from a girder, should consider convenient installation.Otherwise, workers in the installation must be bent to tighten the screw bolt or ladder up, or after the purlins mounted climb purlin tightening screw bolt which is not safe.In addition to consider brace layout position, not in the layout of horizontal strut and bracket.

Eight, windows and doors of angle plates can lump together in construction, because you could not guarantee that plate in the pressure plate crest or trough.

Nine, do bar window apron plate stiffener toward the window direction, so the bar window to the floor, do not go past.In the bar the purlins mounted window to use countersunk head screws.

In ten, the anchor bolts are steel structure warehousegenerally buried civil unit, manufacturer of steel structures of a map, they can sometimes turn bolt location turned 90 degrees, and reexamination, it was too late; and size deviation give you an offset of 50~100mm is not strange.So in the former construction must be reminded, preferably clarification on the basis of language (self protection).In eleven, large project, deepen the figure number must take into account the production, delivery, installation convenience.

Twelve, roof purlin layout and steel detailing should check seriously, often found roof purlin layout and steel detailing the purlin number disagreement.

In thirteen, the node board without stiffening ribs, some designers are not designed for, leading to subsequent welding, node plate deformation.

Fourteen, beam column do tie connecting plate, no holes extended in some places appropriate, because the tie-bar connecting plate on too long, resulting in too small space, tied too long to fit inside.Some secondary beam structures often have this case.In fifteen, light steel structure if maintenance brick wall, must advance with the construction unit and construction unit butt good, because it relates to the construction of steel structure and the problem of two respects, because civil brick probably do not straight, but the color steel plate flashing and could not do suddenly large and small, the result is the color steel and brick wall crack suddenly large and small, color steel plate and the brick wall water treatment is very difficult to do well, make construction unit of a prepared mind.

In sixteen, the upper bar window and door frame too close, no room for Hupon.

In seventeen, the window frame adjacent purlin distances without brace layout, bar end head and the window frame conflict.
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