College】 【weak electrical design and construction of buildings and structures in discussion related to China's weak --- Power By House 【Network】..

<br> Summary: this article for electrical building design and construction and structure-related issues are discussed and proposed design construction should be aware of the problems and solutions for the design, construction, for reference. <br> Keyword: construction electrical structure of .lightning protection <br> <br> In engineering design, many designers are present recognition: construction electrical professional involved pipe's diameter is small, the number of small, simple, and the laying of the lightning protection measures requested are not high, so the electrical .structure of professional and professional plus often neglected, not necessarily. With modern electronic industry and massive rise of intelligent buildings, electrical design of the pipeline will be more and more, lightning protection, anti-electromagnetic pulse and other protection measures have an increasingly higher demand .and, therefore, as part of the equipment design, electrical design with other disciplines in particular coordination between structural professional, support should be given appropriate weight. For this reason, this article will be divided into several areas on the electrical design, construction and construction .-related problems to be addressed. I. use of building structure reinforced for lightning protection and grounding in the architectural lighting design code (GB50057-94), numerous references in the lightning protection design, should give priority to the use of building their own structure .reinforced or natural metal steel structure, as part of the lightning protection equipment, makes security and reliability of balanced economy. Therefore, how to use the building's metal conductor is lightning protection design of important issues. 1, roof structure and jieshan modern architecture in addition .to the pursuit of elevation on a variety of lines, on top of a building also seeks to change shape. Due to the innovative thin-shell, double surface mesh, extensive use of the roof can no longer simply divided into flat roof and pitched roof ., this gives a certain difficulty for lightning protection design. In addition to the design of the architectural lighting design code (GB50057-94) in Appendix II, required on the roof, and highlighting the parts etc. along vulnerable to lightning lightning is set at .the band, directly into the roof structure reinforced as part of the lightning network is also very necessary. Crack for waterproofing, roof structure generally use cast in place concrete slab, reinforced by the upper and lower reinforcement bars, reinforced more dense, more connection points ., and plate reinforced with beams reinforced fastening and connection formation pathways. Highlight the roof of the Tower, staircase, are constructed of reinforced concrete column or columns are connected to the underlying structure. Therefore, when using the building itself reinforced as jieshan Qi, in .structural steel connect key parts of the body such as a column in steel bars and beams reinforced fastening point welding, meets the requirements of electrical pathway formation, is also a section 3.3.5 GB50057-94 articles noted in the description: "in the path .of lightning current flows, some binding points in parallel, it will be safe. This section describes observed: "use of roof bars as jieshan its premise is allowed when concrete roof Lightning has some debris disengaged and a small piece of waterproofing, insulation damage" .. This damage to the roof structure, does not affect the safety of buildings. There are some noteworthy is that highlight the roofing metal such as metal frame, billboards, flagpoles, solar water heaters, cooling towers, aviation obstacle lights, etc., in .addition to its size should be consistent with section 4.4.1 GB50057-94 and section 4.1.2, these metal usually by expansion bolts fixed on the roof, or fixed to concrete bases, they need reliable electrical connections to form the electrical pathway. Highlight .the roof of non-metallic material, according to section 3.3.2 GB50057-94 provides should install jieshan Qi and roof lightning protection device connection. 2. use of concrete columns, wall main bars as mine down lead different structure of various buildings are equipped .with a certain number of reinforced concrete column, as in the masonry of the structure column in the set, in concrete structure set frame columns and shear walls, columns reinforced diameter according to the building seismic design code GB50011-2001, section 7.3.2 masonry .structure column longitudinal reinforcement minimal as 4q> 12, in frame structure frame columns reinforced usually qbl4 above twisted steel can meet GB50057-94, in section 3 and 4.2.1 requirements 3.5. Pillar reinforcement in the form of connection is usually used fastening and .connection, welding and mechanical connections, in accordance with the electrical equipment installation engineering grounding equipment construction and acceptance (GB50169-92) provides that the lightning down lead connection to lap welding, lap length is 6 times the diameter of round bar, therefore, not .allowed to use threaded steel instead of round bar steel for lap. In addition, as a down lead primary steel in civil right in if you are using touch welding (in project commonly used welding form of Flash butt welding and electroslag welding, belong to the .right touch welding), should touch the welding Department according to the specification for welding and lap steel. 3. use beam as grounding building Foundation forms can be divided into no gluten extended base and extended base, post the following Bar Foundation, raft, box .Foundation, as well as composite Foundation pile. Article by GB50057-94, section 3.2.4: 3.3.5, 3.4.3, section 4.4.3, grounding: ground should be in the following section 4.3.5 50cm also States: securing .the "ray of artificial grounding from building out a population or sidewalk should not be less than 3m, when less than 3m horizontally grounding partial depth should not be less than 1m or take insulation protection measures. Building base depth typically consists of the Foundation's own height ., ground embedded pipelines corrosion depth height and antifreeze, and other factors that generally greater than 0.5m. But in masonry, wall Bar Foundation owing to the building waterproof, Foundation ring beam is typically set to elevation-0.060 Office, to replace moisture-proof .coating, therefore cannot be used as a grounding device. While the Bar Foundation under column and raft, box Foundation in basic bottom with rib beams, columns of the independent Foundation and various types of pile foundation are equipped with basic drawing beams or beam, above .all to meet as a basic grounding device. 2. electric pipeline embedded and structural layout of the electrical pipeline laying clear enough and concealed. The downleadPipe installation in walls, ceiling surface, have little effect on the structure of, and concealed is entirely different. .Concealed, electrical line of embedded is the construction and installation engineering. Electrical characteristics of embedded pipelines are elements, floor complex, especially in the wall of the vertical embedded pipelines and in floor level embedded in the pipeline due to weakened structural members section, a certain .impact on the structure, the following will be discussed several aspects of 1, vertical embedded pipelines in structural wall laying when vertical embedded pipelines laid in reinforced concrete columns or reinforced concrete shear walls, laying method is relatively simple, only need to change the line pipe .and steel pipe and structural steel lashing, prevent the placement of vibrating concrete time deviation. Because electric pipeline diameter smaller, on concrete wall, pillar has little effect on flexible layout options as necessary. However, when the pipeline laying vertically to masonry wall, laying .way relatively complex, this is the electric installation works and civil engineering contradiction in more places. Structural wall there are mainly in the form of masonry structures of bearing walls and concrete structures in non-load-bearing walls, below the two cases discussed separately ( .1) in the masonry wall on the laying of masonry structures including brick masonry, concrete, masonry, stone masonry, etc. First of all, in masonry structure does not allow the creation of horizontal and inclined to pass trough, level embedded pipelines usually planted .on each floor beam. Buried into the body of the vertical pipe before are embedded directly in the wall laid on tick Groove, but this approach will cause injury on wall, especially when the parallel laying of the pipeline more, on the whole wall section of .carrying capacity. According to the brick structure design code (GB50003-2001), no. 6.2.14 "should not be in the section on the long side less than 500 mm of bearing wall, independent column in the laying of the pipeline; not .in the wall through the dark lines or reserved, dug trench, cannot avoid should take the necessary measures or weakened after the section checking wall carrying capacity ". Currently feasible method is left in the masonry brick wall 120 deep notches, width according to the number .of parallel pipeline adopts a brick or a half-brick, pipeline embedded after C20 fine stone concrete fill it. When you use Hollow bricks or concrete hollow blocks, one approach is to use the holes in masonry laid pipelines, 2001 by GB50003-section 6.2 ..14 bar note in the "to force a smaller or not filling holes in masonry, wall vertical holes 1 and set the pipeline. But in fact commonly used KPl-brick aperture approximately 20mm, DMl-brick aperture approximately 18mm, smaller, and block .the heavier, group require masonry joints staggered ash, the method of construction. When the wall is a half-brick, in accordance with the specifications, in half-brick walls not concealed in the pipeline, such as the inevitable, the local provision of .concrete structure column, the pipeline laying in the column. (2) in the concrete structure fills the wall embedded concrete structure wall only bear the weight of the wall itself, commonly used with aerated concrete block, fly-ash concrete hollow blocks, and so .on, such material is characterized by low strength, light weight, even in the event of damage to the main structure has no effect. Therefore, fill the holes in the wall just needed to consider cracking resistance, noise and other factors, in fill wall .slotted should not be more than half of the wall thickness. 2. horizontal embedded pipelines in structure floor laying of floor structure mainly on prefabricated slabs, as well as in-situ concrete floor slab, ribbed slabs, laminated slabs, etc., because the .first two forms of the more common, here only needle precast and cast-in-place concrete floor buildings-Kun in two forms. (1) horizontal tube in prefabricated floor laying of prefabricated prestressed precast concrete slabs including large floor and bi-directional precast .prestressed hollow slab, typically using prestressed concrete hollow core slabs. Although the press plate of steel bars with different types of cold-drawn steel wire, cold rolled ribbed bar, and other differences, but the Board's section and bar arrangement is basically the same as .the form. In prefabricated floor layout pipelines need beforehand to understand the structure of professional layout of the module so that the pipeline along a circular hole in the module or Panel joints. It should be noted that, in the round hole layout pipeline, leads to .pick holes to avoid loading the main reinforcement plate. Common with a circular hole in the section and the main bar location. When the pipeline layout along the seams, as is usually the Board width 20-30mm, embedded pipelines cause filling hard dense, discuss .it with the structure of the profession to take 40-50mm seams, joints in a root q> 12 bars to be addressed. (2) horizontal embedded pipelines in situ concrete floor laying with concrete materials and construction technology advances, cast concrete floor? .Kun to gradually reduce the cost of the construction process step by step to simplify the application scope, more and more widely. Electric pipeline in cast slab floor way more flexible, but it should be noted that it will be a pipeline in cast plate cross or .side-by-side arrangement, at the same time as the national civil construction engineering technology measures the electrical part of section 5.1.9 points out: laying in reinforced concrete cast in place concrete floor of wire and pipe outside diameter of not more than the .maximum thickness of 1 / 3. This is because the slab thickness generally 80-150mm, pipeline on concrete cross sections of relatively large, and pass a long pipeline would result in a concrete plate, weak belt will cause processing accidentally? Kun concrete slab cracking ., or leave a project risk. In cast slab laying horizontal embedded tube should also take measures to prevent mechanical damage, laying in the cast of pipeline bending radius not less than 10 times the outer diameter..