【正文】 在計(jì)算結(jié)構(gòu)高度時(shí)，突出屋面的小屋可不予考慮。 另外，多層桁架結(jié)構(gòu)的高度應(yīng)取為從curb level到平屋頂?shù)奈菝媪旱淖罡唿c(diǎn)或到坡度大于25%的坡屋面的平均高度處的豎直距離。1螺栓連接及焊縫連接的作用范圍完全受拉的高強(qiáng)度螺栓（ or ）或焊縫可用于下列連接：結(jié)構(gòu)高度大于或等于200英尺（60mm）的柱的拼接； 最小的水平方向尺寸小于40%的結(jié)構(gòu)高度，且結(jié)構(gòu)高度介于100英尺（30mm）到200英尺（60mm）的柱的拼接； 最小的水平方向尺寸小于25%的結(jié)構(gòu)高度，且結(jié)構(gòu)高度小于100英尺（30mm）的柱的拼接； 在高度超過125英尺（38mm）的結(jié)構(gòu)中，梁與柱的連接以及與柱間支撐相連的其他梁的連接； 在安裝有超過5噸（50KN）起重量的起重機(jī)的結(jié)構(gòu)中：屋頂桁架的拼接，桁架與柱的連接，柱的拼接，以及柱間支撐、斜撐、起重機(jī)支座處的連接； 產(chǎn)生沖擊荷載或反向應(yīng)力的活荷載處的支撐連接及活動(dòng)及其支座連接； 設(shè)計(jì)圖中指定的其他連接。在對結(jié)構(gòu)進(jìn)行焊縫加固改造時(shí)，符合滑移破壞連接的已有的鉚釘和高強(qiáng)度螺栓可認(rèn)為能承受部分荷載，而焊縫只需提供所需的另外部分設(shè)計(jì)強(qiáng)度。如果使用焊縫了，則焊縫應(yīng)能承受連接中的全部外力。焊縫和螺栓的布置對于傳遞軸力的構(gòu)件的連接，連接處焊縫群或螺栓群的重心應(yīng)與構(gòu)件的重心重合，除非規(guī)定有偏心情況。如果焊接檢查孔和梁蓋板的切割過渡部分是通過預(yù)先鉆或鋸而成的，則檢查孔或頂面的這部分無需打磨，也不需要通過染色滲透或磁性方法檢查。對于熱軋鋼和組合型鋼的截面，梁蓋板和焊接檢查孔應(yīng)沒有凹槽和尖角，在組合截面中翼緣和腹板間采用角焊縫連接時(shí)，允許檢查孔在與翼緣垂直的地方結(jié)束。檢查孔的高度應(yīng)滿足焊接金屬在相鄰板件間的堆積。例如，翼緣采用部分熔透坡口焊，腹板采用角焊縫拼接、或螺栓拼接、或螺栓和角焊縫混合拼接。當(dāng)用STM A6/A6M第四組和第五組的型鋼或用厚度超過2英寸（50mm）的鋼板焊接而成的組合截面來拼接構(gòu)成一個(gè)截面，且該截面主要為受壓作用時(shí)。當(dāng)上述截面的拉力通過全溶透坡口焊縫的拼接來傳遞時(shí)。重型截面的連接本節(jié)適合于ASTM A6/A6M第四組和第五組的螺紋鋼，厚度超過2英寸（50mm）的鋼板焊接構(gòu)成的組合截面，以及承受由拉伸或彎曲產(chǎn)生的主應(yīng)力的橫截面。當(dāng)除了柱以外的其他受壓構(gòu)件打磨后支撐時(shí)，拼接材料以及連接件的布置應(yīng)保證所有部件在一條線上，而且應(yīng)該能承受百分之五十的構(gòu)件強(qiáng)度。梁端的柔性連接節(jié)點(diǎn)允許簡支梁端轉(zhuǎn)動(dòng)，所以，連接允許出現(xiàn)剛性但自我限制的變形受彎連接設(shè)計(jì)轉(zhuǎn)動(dòng)受限制的梁及桁架的端部連接時(shí)應(yīng)考慮由于連接的剛性引起的彎矩和剪力的組合效應(yīng)。J概述設(shè)計(jì)原則連接包括連接構(gòu)件的受影響部分（例如梁腹板），連接單元（例如節(jié)點(diǎn)板，角鋼，brackets）及連接件（焊縫，螺栓，鉚釘）。 for example partialjointpenetration flange groove welds with filletwelded surfacelap plate splices on the web, bolted lap plate splices, or bination bolted/filletwelded lap plate splices.6. Beam Copes and Weld Access HolesAll weld access holes required to facilitate welding operations shall have a length from the toe of the weld preparation not less than 11 2 times the thickness of the material in which the hole is made. The height of the access hole shall be adequate for deposition of sound weld metal in the adjacent plates and provide clearance for weld tabs for the weld in the material in which the hole is made, but not less than the thickness of the material. In hotrolled shapes and builtup shapes, all beam copes and weld access holes shall be shaped free of notches and sharp reentrant corners,except that when fillet webtoflange welds are used in builtup shapes, access holes are permitted to terminate perpendicular to the flange.For ASTM A6/A6M Group 4 and 5 shapes and builtup shapes of material more than two in. (50 mm) thick, the thermally cut surfaces of beam copes and weld access holes shall be ground to bright metal and inspected by either magnetic particle or dye penetrant methods prior to deposition of splice welds. If the curved transition portion of weld access holes and beam copes are formed by predrilled orsawed holes, that portion of the access hole or cope need not be access holes and beam copes in other shapes need not be ground nor inspected by dye penetrant or magnetic particle methods.7. Minimum Strength of ConnectionsConnections providing design strength shall be designed to support a factored load not less than 10 kips (44 kN), except for lacing, sag rods, or girts.8. Placement of Welds and BoltsGroups of welds or bolts at the ends of any member which transmit axial force into that member shall be sized so that the center of gravity of the group coincides with the center of gravity of the member, unless provision is made for the foregoing provision is not applicable to end connections of staticallyloaded single angle, double angle, and similar members.9. Bolts in Combination with WeldsIn new work, A307 bolts or highstrength bolts proportioned as bearingtypeconnections shall not be considered as sharing the load in bination with welds.Welds, if used, shall be proportioned for the entire force in the connection. Inslipcritical connections, highstrength bolts are permitted to be considered as sharing the load with the welds. These calculations shall be made at factored loads.In making welded alterations to structures, existing rivets and highstrength bolts tightened to the requirements for slipcritical connections are permitted to beutilized for carrying loads present at the time of alteration and the welding needonly provide the additional design strength required.10. HighStrength Bolts in Combination with RivetsIn both new work and alterations, in connections designed as slipcritical connections in accordance with the provisions of Section J3, highstrength bolts arepermitted to be considered as sharing the load with rivets.11. Limitations on Bolted and Welded ConnectionsFully pretensioned highstrength bolts (see Table or ) or welds shall be used for the following connections:Column splices in all tier structures 200 ft (60 m) or more in height.Column splices in tier structures 100 (30 m) to 200 ft (60 m) in height, if the least horizontal dimension is less than 40 percent of the height.Column splices in tier structures less than 100 ft (30 m) in height, if the least horizontal dimension is less than 25 percent of the height.Connections of all beams and girders to columns and of any other beams andgirders on which the bracing of columns is dependent, in structures over 125 ft (38 m) in height.In all structures carrying cranes of over fiveton (50 kN) capacity: rooftrusssplices and connections of trusses to colum