現(xiàn)澆板厚度選取Thicknessselectionofcast-in-placeslab

1、現(xiàn)澆板厚度選取( Thickness selection of cast-in-place slab)The thickness of the one-way plate is not less than 1/30L, the two-way plate is not less than 1/35L, and the minimumthickness of the floor panel is not less than 90mm, and the minimum thickness of the roof plate is not less than 100mm. The slab thic

2、kness of adjacent cast in place shall not be more than 30mmProvisions for reinforcement of cast-in-place slabs:(1) the reinforcement of cast-in-place slab shall be designed according to the principle of fine reinforcement.(2) the cast-in-place slab shall be controlled with a minimum reinforcement ra

3、tio greater than 0.25%.(3) the plate near the gable should be equipped with double layers of reinforcing steelmesh. Adding radial reinforcementat the corner of the wall. In the region where the temperature and shrinkage stress are greater, a double layer steel mesh should be installed.(4) double rei

4、nforcement shall be adopted for roof bar reinforcement.(5) double deck two-way steel bars shall be installed in cast-in-place slabs with a thickness of more than 120mm.Residential construction expansion joints and concrete components, protective layer thickness should be strictly in accordance with

5、the provisions of the corresponding norms.Longitudinal length of longer (generally more than 40m) of the building can be used after the treatment of the casting belt,or can be in the house every 20mor so on the plate on the support (sub households, partitions) to sew.The cast-in-place concrete plate

6、 can compensate the shrinkage of concrete by adding a proper amount of admixture.Whenthe strength grade of cast-in-place concrete slab is more than C30, priority should be given to the use of high performance concrete.The crack control of cast-in-place slab should be based on the characteristics of

7、its structure and structure, and should be strengthened by the principle of structure strengthening and releasing stress when necessary.In the design of cast-in-place slab, crack control should be carried out, and the width of crack should be controlled less than 0.2mm.The length of the negative rei

8、nforcement of the plate should be determined according to the negative momentenvelope diagram of the plate.How to determine the cast-in-place plate thicknessThe elevation of floor beam and slab and the determination of cast-in-place slab thicknessScope: according to the practice of building ground a

9、nd pipeline to determine floor beam and slab elevation and slabthickness; according to the floor elevation, surface layer thickness, the height of the window height determination of lintels.Outline: 1, in the process of engineering services, many construction units proposed: in the surface treatment

10、 process, in order to ensure the windowsill height, and meet the requirements of professional pipe laying, it is very difficult. In the design process, the structural designer how to determine the floor top elevation with the building and plumbing designers; it is important to determine the floor th

11、ickness according to the direction of the electrical designers. 2, how to make the door and window highly conform to the modulus, so that both construction convenience, and reduce cost, and let users in the use of engineering can feel comfortable.Coordinate the lintels height and surface layer thick

12、ness is very necessary.This paper takes residential buildings for example:For residential buildings, the floor can be divided into two ways: the pipeline, the cushion and the non cushion. Without the cushion floor, the surface layer method is simple, the floor weight is small, and the cost can be sa

13、ved. From the bottom up can be divided into:Cast-in-place slabPlain mudCombined with leveling layer 30mmTile 8mm10mmThe total thickness is 40mm.Residential buildings nowrequire plumbing, household metering, if the pipe is not buried, cushion will have to take the ceiling, the residential floor heigh

14、t, and impossible ceiling, exposure will affect the appearance of the pipe. There are few ways that the pipeline does not take the cushion, and most of them are treated by the form of cushion and buried pipe. Whenthe cushion in the tap water pipe and the heating pipe intersection, combined with laye

15、r 80mm,the total thickness will increase to 100mm.See the details of a specific practice. In order to reserve accurate surface layer thickness during the design process, the installation of the water heating pipe is guaranteed, and the dead load of the building panel is not increased because the sur

16、face layer is too thick. This requires the construction unit in the design tasks assigned to determine the various heating methods and piping forms; plumbing designers in the building after the proposed conditions, as soon as possible to determine the direction of the pipeline.For a room with only a

17、 heating tube. The surface thickness is desirable 70mm.Meet the one-way walking tube and the thickness of the furring brick. See detail two.As masonry residential buildings, the floor height is mostly 2900mm and 3000mm, and we are now 2900mm storey analysis. Thedoorway height is 2100mm, 2200mm, 2400

18、mm, 2700mm in the standard drawing. The window has 1200mm,1400mm,1500mm,1800mm, 2100mm in the height of the standard drawing. The window high 900mm high ledge also with 2100mm, 2300mm, 2400mm module, unless the elevation effect of special requirements, the upper elevation of the doors and windows we

19、 can design according to the same elevation. So we can choose 2100mm and2400mm two, if you choose the door to door high 2100mm, upper floor top elevation is 700 to 800mm, more than 600mm height can not be used together with two lintel lintel, some waste and superfluous. So I suggest building designe

20、rs in high degree to choose when Windows 2400mm high gate (residentialbuildings).As the height (2900mm)- (2400mm)- high surface layer thickness (about 90mm) = H (= 410mm) lintel. For high 2400mm gate, the user if you want good lighting in the upper door is added on the panel,If you think the lightin

21、g has been used, you can directly do 2400m high door. I think the height of 2400mm2500mm is the right size for all the lights, leaving room for the user to decorate himself. The window lintel (H = 350mm450mmto) remove the plate thickness of 100, the remaining part of the lighting and installation of

22、 curtain box is more appropriate. In the range of over beam height (H = 350mm to 450mm), the minimum reinforcement ratio is calculated for the force calculation. It's also the most economical height. Masonry structure reinforcement concrete lintel see detail three. This will leave room for futur

23、e users, and reduce the construction cost of the construction of the main part of the project.For the frame residential buildings, because residential buildings are not too large size of the room into the depth, mostly between 3000mm4800mmA.ccording to the design practice experience, the overall hei

24、ght of the cast-in-place frame beam is generally H (1 / 101 / 12) L, and the height of the fabricated and assembled integral frame beam is the best between (1 / 81 / 10) L. Nowadays, residential buildings are seldom constructed in the form of assembly and assembly. The span of the cast-in-place inte

25、gral frame 3000mm 4800mm (1 / 101 / 12) is also between (350mm 450mm). In full compliance with the aforementioned surface layer, doors and windows, high beam coordination. This is not required in the beamunder the hanging plate (see detail four) and the other with precast lintel. Can meet the ideal

26、requirements. The beamspan ratio of beamsection is too large can not only reduce the reinforcement, but because of the stiffness and increase the minimum reinforcement ratio in order to meet the requirements of increasing reinforcement, if will form a short beam (span 5) would be more reasonable.The

27、refore, the beam has a reasonable span to depth ratio is a reasonable structure, reducing the cost of an important factor.The high-rise shear wall structure form of residential buildings with brick lintels form of high-rise residential buildings. Because of multiple layers, the thickness and surface

28、 layer approach should be more accurate control, a design of the heart, or convenience. It will cause each layer is poor, the total number of layers can add up to big difference.Previously mentioned doors and windows height, for doors and windows work and craft, our architectural design personnel ca

29、n not have a deep understanding, so still try to follow the atlasrequirements of the standard size more appropriate. Changethe original size, the amount of material used is difficult to grasp. Many cases are to take the upper limit of the material (such as 1600 high windows, we choose the practice w

30、ill be 1800 high window as the basis of selection), resulting in construction difficulties and waste of materials.For the kitchen, bathroom, waterproof and soundproof floorCast-in-place slabLightweight aggregate concrete insulation layer 60mmPlain cement mortarLeveling of cement mortar 20mmThe base

31、treatment agent together1.5 thick waterproof coatingCombined with leveling layer 30mm:Tiles 8mm to 10mmPlus the 20mmfloor drop of the building whenthe water is wrong. The structural elevation needs to fall by 140mmabove the normal floor height. The structure design personnel can adjust the door lint

32、el height or top elevation beam to ensure the door height unchanged.Board whenthreading pipe (Electrical), especially in the tube wire lead source, the thickness should be equal to or greater than 120, should not be used with thin cushion (cushion for plumbing practice reserved space). The top eleva

33、tion is different at the same time,The upper ribs of the plate shall be separated or obliquely passed (detail five).Residential buildings basically have no large width, the cast-in-place slab thickness generally take 80140. For multi-storey residential small hall room with 80 thick plate, can reduce

34、 the minimum reinforcement ratio; in the premise of the crack and deflection of the big room with a thin plate, can save steel consumption or increase the height of the room). For high-rise residential buildings, the slab thickness should not be less than 100mm in order to satisfy the assumption tha

35、t the in-plane stiffness of the floor is infinite and the in-plane stiffness is zero. But in order to increase the floor height (the height of certain height decreasing of thickness increase) and reduce the self weight of buildings (floor thickness and weight reduction), slab thickness meet the stif

36、fness and crack deflection requirements can be assumed(the basement roof, and embeddedlayer requirements of the board except). According to the laboratory test data, the calculation of the cast-in-place slab is very conservative, and our use of PKPM to generate reinforcement has been able to fully m

37、eet the safety requirements. There is no need for artificial and conservative calculations. The thickness of the floor and the surface should be strictly controlled in the design process, as far as possible, that is reasonable and economic.The stress bar spacing is not greater than 200mm, in order to facilitate the construction of control, reinforcement spacing as far as possible the use of 200mm;