工程建设标准强制性条文CPECSB5房屋建筑部分（英文版）.doc

Section V Structure Design1. Basic Provisions1.1 Safety Grades for StructuresUnified Standard for Architectural Structure Design GBJ 68 841.0.5 Different safety grades shall be applied in the design of architectural structures according to the seriousness of possible consequences (endangering the lives of people, causing economic losses, producing social impact, etc.) that might be resulted from damage to structure. The classification of safety grades for architectural structures shall comply with the requirements in Table 1.0.5.Safety grades for architectural structures Table 1.0.5Safety gradeConsequence of damageType of buildingsIIIIIIVery seriousSeriousNot seriousImportant industrial and civilian buildingsOrdinary industrial and civilian buildingsSecondary buildingsNotes: The safety grade for special buildings shall be determined separately according to actual conditions; When the design is performed according to anti-seismic requirements, the safety grade of architectural structures shall comply with the provisions in “Specification for anti-seismic design for buildings”1.2 Structure Load and CombinationsSpecification on Loading for Architectural Structures GBJ 9 872.2.1 In the architectural structure design, load effect combinations shall be taken on the basis of the loads that might occur simultaneously on the structure during the application according to bearing capacity limit status and normal application limit status, and the most unfavorable combination in each case shall be taken.2.2.2 For the bearing capacity limit status, design shall be made with the basic combination and accidental combination of load effects, and the following design expressions shall be adopted:g0SR(2.2.2)Whereg 0Importance coefficient of structure, and can be taken respectively as 1.1, 1.0 and 0.9 for structural members with safety grades I, II and III; the safety grade of structural members shall be determined according to the provisions in relevant design specifications for architectural structures;SDesign value of load effect combination;RDesign value of resistance of structural members, and shall be determined according to the provisions in relevant design specifications for architectural structures;2.2.5 For normal application limit status, design shall be made respectively with the short term effect combination and long term effect combination of the load on the basis of different design requirements.2.2.6 The partial safety factor of the load shall be adopted according to the following provisions:I. Partial safety factor for permanent load:It shall be taken as 1.2 when its effect is unfavorable to the structure;It shall be taken as 1.0 when its effect is favorable to the structure.II. Partial safety factor for variable load:It is taken as 1.4 under normal conditions;It is taken as 1.3 for floor structure when the standard value of live load is not less than 4kN/m2.Note: In the proof calculation of tipping and sliding displacement, the partial safety factor of permanent load favorable to tipping and sliding displacement can be taken as 0.9; for some special cases, it shall be determined according to the provisions in relevant design specifications for architectural structures.2.2.7 Under normal conditions, the load combination value coefficient is taken as 0.6 when the wind load is included in the combination, and as 1.0 when no wind load is included in the combination.For ordinary bent and frame structures, the load combination coefficient is taken as 0.85 when two or more variable loads, including wind load, are included in the combination; and as 1.0 in all other cases.3.1.1 The standard values and quasi-permanent value coefficient for evenly distributed live load on flooring of civilian buildings shall be taken as per provisions in Table 3.1.1.Standard values and quasi-permanent value coefficient for evenlydistributed live load on flooring of civilian buildings Table 3.1.1No.TypeStandard value(kN/m2)Quasi-permanent value coefficient yq1Resident, dormitory, hotel, office building, hospital wards, nursery, kindergarten1.50.42Classroom, laboratory, reading room, conference room2.00.53Canteen and archive room for ordinary document in office building2.50.54Auditorium, theater, cinema and stadium stand:(1) with fixed seats(2) without fixed seats2.5 3.50.35Exhibition hall3.00.56Store3.50.57Station hall, waiting room, stage and gymnastic room3.50.58Library, archive library5.00.89Parking lot:(1) Single oriented flooring (with span no less than 2m)(2) Bidirectional flooring and flooring without beam (pillar grid dimension no less than 6m6m) 4.02.50.610Kitchen2.00.511Bathroom, WC and toilet:(1) for civilian buildings in item 1(2) for other civilian buildings2.012Corridor, lobby and stairs:(1) residence, nursery and kindergarten(2) dormitory, hotel, hospital and office building(3) classroom and canteen(4) auditorium, theater, cinema, stand and exhibition hall1.52.013Extended veranda2.50.5Notes: The various live load given in this table apply to general application conditions, when the application load is larger, they shall be applied according to actual conditions. The live load in Item 9 is only applicable to parking lot for cars. When the single directional slab span is less than 2m, the wheel local load is converted into equivalent evenly distributed load and the local load value is taken as 4.5kN, spaced of 1.5m and distributed over an area of 0.2m0.2m. For the live load of stair in Item 12, proof calculation shall be done as for an 1.5kN concentrated load for the step plates of fabricated stairs. For the load of extended veranda in Item 13, it can be taken as 3.5kN/m2 when there might be a dense flow of people. All loads in this table do not include the self-weight of the partition walls.3.3.1 For house roofing, the evenly distributed live load on the roofing in the horizontal projection plane shall be taken according to Table 3.3.1.The evenly distributed live load on the roofing shall not be taken into account concurrently with snow load.Evenly distributed live load on the roofing Table 3.3.1No.TypeStandard value(kN/m2)Quasi-permanent value coefficient yq1Unmanned roof:Light roofing of asbestos and corrugated iron sheets and tiled roofsLight roofing of wire reinforced cement or other cement products and reinforced concrete roofing supported by thin structural steelReinforced concrete roofing supported by structural steel or reinforced concrete structures, including cornice and canopy0002Manned roofing1.50.4Notes: For unmanned roofing, the values shall be taken according to actual conditions if the construction load is high. For manned roofing, they shall be taken as for corresponding roofing live loads when it is also used for other purposes.3.5.1 In the design of roofing plates, purlins, reinforced concrete cornices, canopies and fabricated minor beams, proof calculation shall be performed as follows for the cases when construction load or concentrated maintenance load (self weight of people and small tools) appear at the most unfavorable positions:I. It is taken as 0.8kN for roofing plates, purlins, reinforced concrete cornices and fabricated minor beams;II. It is taken as 1.0kN for reinforced concrete canopies.Notes: For light members or members with large breadth, when the construction load might exceed the above load, proof calculation shall be performed according to actual conditions, or temporary supports and padding plates shall be provided. In the calculation of the strength of cornices and canopies, one concentrated load shall be taken into account for every 1.0m along the width of the plate; in the proof calculation of tipping of cornices and canopies, one concentrated load shall be taken into account for every 2.53.0m along the width of the plate.3.5.2 The horizontal load on the top of rails for stairs, stands, verandas and manned roofing shall be taken according to the following provisions:I. It shall be taken as 0.5kN/m for residence, dormitory, office building, hotel, hospital, nursery and kindergarten;II. It shall be taken as 1.0kN/m for schools, canteen, theater, cinema, station, auditorium, exhibition hall or stadium.3.6.1 For the dynamic calculation in the design of architectural structures, it can be performed as for static calculation by multiplying the weight or equipment load with a dynamic coefficient when there is sufficient basis.5.1.1 The standard value of snow load on the horizontal projection plane of roofing shall be calculated according to the following formula:sk=m rs0(5.1.1)Where skStandard value of snow load, kN/m2;mrDistribution coefficient of snow on roof;S0Basic snow pressure, kN/m The basic snow pressure shall be determined as the self weight of the maximum accumulated snow once in 30 years on empty and flat ground in the local area.5.2.2 In the design of load bearing members of building structures and roofing, the distribution of accumulated snow shall be taken into consideration according to the following provisions:I. The most unfavorable condition of uneven distribution of accumulated snow for roofing plates and purlins;II. The even distribution of accumulated snow over the whole or half span respectively for trusses;III. The even distribution of accumulated snow over the whole span for frames and columns.6.1.1 The standard value of wind load vertical to the surface of a building shall be calculated according to the following formula:wk=b zmzw0(6.1.1)Where wkStandard value of wind load, kN/m2;bzWind vibration coefficient at height of z;msWind load body shape coefficient;mzWind pressure variation coefficient with height;w0Basic wind pressure, kN/m The basic wind pressure shall be determined on the basis of maximum wind speed averaged in 10 min. v0 (m/s) at 10m above ground once in 30 years on a fairly empty and flat ground in the local area, at a value of w0=v02/1600.The basic wind pressure shall not be less than 0.25 kN/m2.For high-rise buildings, the basic wind pressure shall be taken as the basic wind pressure value multiplied by a coefficient of 1.1; for high-rise buildings of particularly importance and with special requirements, the basic wind pressure shall be taken as the basic wind pressure value multiplied by a coefficient of 1.2.2. Design of Concrete Structures2.1 Reinforced Concrete StructuresDesign specification for reinforced concrete structures GBJ 10 892.1.3 The standard values of concrete strength shall be taken from Table 2.1.3.Standard values of concrete strength (N/mm2) Table 2.1.3Type of strengthSignConcrete strength gradeC7.5C10C15C20C25C30C35C40C45C50C55C60Axial center compressionBending compressionTensilefckfcmkftk55.50.710111.213.5151.51718.51.752022223.5262.252729.52.4529.532.52.632352.753437.52.853639.52.952.1.4 The design values of concrete strength shall be taken from Table 2.1.4.Design values of concrete strength (N/mm2)Table 2.1.4Type of strengthSignConcrete strength gradeC7.5C10C15C20C25C30C35C40C45C50C55C60Axial center compressionBending compressionTensilefcfcmft555.50.610111.112.513.51.31516.51.517.5191.6519.521.51.821.523.51.923.526225292.2Note: In calculation of cast-in-situ reinforced concrete members compressed at axial center or eccentrically, if the long side or main machine of the section is less than 300mm, the design values of the concrete strength in the table shall be multiplied by a coefficient of .2 The strength standard value of reinforcement shall have a guarantee rate no less than 95%.The strength standard value of reinforcement shall be taken from Table 2.2.2-1, and the strength standard value of steel wires and strand steel wires shall be taken from Table 2.2.2-2.Strength standard values of reinforcement (N/mm2)Table 2.2.2-1Typefyk or fpyk or fatk or fptkHot rolled reinforcementGrade I(Q235)235Grade II(20MnSi,20MnNb(b)335Grade III(20MnSiV,20MnTi,K20MnSi)400Grade IV(40Si2MnV,45SiMnV,45Si2MnTi540Cold drawn reinforcementGrade I (d12)280Grade II d25 d=2840450430Grade III500Grade IV700Cold rolled reinforcement with ribLL550 (d=412)550LL650(d=4,5,6)650LL800(d=5)800Heat treated reinforcement40Si2Mn(d=6)48Si2Mn(d=8.2)45Si2Cr(d=10)1470Strength standard values of steel wires and strand steel wires (N/mm2)Table 2.2.2-2Typefatk or fptkCarbon wire4,51770,1670,1570,147061670,15707,8,91570,1470Indented wire5,71570,1470Cold drawn low carbon wireGrade A:45Group I700650Group II650600Grade B: 35550Strand steel wire2 wired=10.0d=12.017203 wiresd=10.8d=12.917207 wiresd=9.5d=11.1d=12.7d=15.21860186018601860,1820,1720(d=9.0)(1770,1670)(d=12.0)(1670,1570)(d=15.0)(1470,1470)Note: The strength standard value of Grade A cold drawn low carbon wire used as prestressed reinforcement shall reduce by 50N/mm2 after mechanical straightening.2.2.3 The tensile strength design values of reinforcement fy or fpy and the compression strength design values of reinforcement fy or fpy shall be taken from Table 2.2.3-1, and the tensile strength design values of steel wires and strand steel wires fy or fpy and the compression strength design values of steel wires and strand steel wires fy or fpy shall be taken from Table 2.2.3-2.Tensile strength design values of reinforcement (N/mm2) Table 2.2.3-1Typefy or fpyfy or fpyHot rolled reinforcementGrade I(Q235)210210Grade II(20MnSi,20MnNb(b)310310Grade III(20MnSiV,20MnTi,K20MnSi)360360Grade IV(40Si2MnV,45SiMnV,45Si2MnTi500400Cold drawn reinforcementGrade I (d12)250210Grade IId25380310d=2840360310Grade III420360Grade IV580400Cold rolled reinforcement with ribLL550 (d=412)360360LL650 (d=4,5,6)430380LL800 (d=5)530380Heat treated reinforcement40Si2Mn(d=6)48Si2Mn(d=8.2)45Si2Cr(d=10)1000400Notes: In reinforced concrete structures, the tensile strength design value of reinforcement in members subject to axial center tensile and minor eccentric tensile shall still be taken as 310N/mm2 when it is greater than 310N/mm2, and the tensile strength design value of reinforcement in other members shall still be taken as 360N/mm2 when it is greater than 360N/mm2; for Grade I reinforcement with a diameter greater than 12mm, the strength after cold drawing must not be used if it is cold drawn; When the concrete strength grade of the reinforced concrete structure is C10, the strength design value of smooth bars shall be taken as 190 N/mm2, and that of deformed bars as 230 N/mm2; The tensile strength design value of Grade LL550 cold drawn reinforcement with ribs supplied in coils shall reduce by 20 N/mm2 after mechanical straightening, and the compression strength design value shall not be greater than the corresponding tensile strength design value; When there are different types of reinforced bars in a member, their respective strength design values shall be taken for different types of bars according to their condition under load.Compression strength design values of steel wires and strand steel wires (N/mm2) Table 2.2.3-2Typefy or fpyfy or fpyCarbon wire49fptkptk=16701130fptk=15701070fptk=14701000Indented wire5,7fptk=1570107060fptk=14701000Cold drawn low carbon wireGrade AGroupGroup IGroup II40044604305430400Grade BFor welding skeleton and welding mesh320320For binding skeleton and binding mesh250250Strand steel wire2 wirefptk=172011703603 wiresfptk=172011703607 wiresfptkptk=18201240(fptk=1770)(1200)fptk=17201170(fptk=1670)(1130)(fptk=1570)(1070)(fptk=1470)(1000)Notes: When cold drawn low carbon wires are used as Prestressed reinforcement, inspection shall be made coil by coil according to the wire strength standard values specified in Table 2.2.2-2, and the strength design values for Grade A shall be taken; Grade B cold drawn low carbon wires can be inspected by batches, and should be used for welded skeletons, welded meshes, erecting stand bars, stirrups and structural reinforcement; The tensile strength design value of Grade A cold drawn low carbon wires used as Prestressed reinforcement shall reduce by 30 N/mm2 after mechanical straightening, and the compression strength design value shall not be greater than the corresponding tensile strength design value; When the strength standard values of carbon steel wires, indented steel wires and strand steel wires do not comply with the provisions in Table 2.2.2-2, proof calculation shall be performed for their strength design values; Values in brackets in the table are the strength standard values and design values of strand steel wires produced according to National Standard GB 5224-85 and now in use for an extended period.3.1.4 The load design values shall be used for the bearing capacity (including loss of stability under compression yield) calculation and tipping and sliding displacement proof calculation of structural members