JP2018151198A - Fire resistance performance test piece of floor beam structure and fire resistance performance test method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a test piece and a test method capable of properly obtaining a deformation amount of a floor beam in such a manner not to generate a stress for resisting the deformation of a floor beam in a frame body for supporting a ceiling material, a floor slab and the like on upper and under parts of the floor beam at the time of a load heating test of the floor beam structure by a membrane fire-resisting method.SOLUTION: A frame body 5 provided so as to surround the middle portion of a floor beam 2 includes: a suspension frame 6 arranged above a floor beam 2 and mounted on the floor beam 2; and a floor assembly frame 7 suspended by the suspension frame 6 and arranged on a lateral side of the floor beam 2. A floor slab 4 is mounted between the floor beam 2 and the floor assembly frame 7. A ceiling material 3 is stretched below the floor assembly frame 7, and a whole weight of a frame boy 5, a floor slab 4, and a ceiling material 3 or the like is loaded on the floor beam 2. The suspension frame 6 is connected to the floor beam 2 via a node which permits a displacement in a deflection direction of the floor beam 2. The floor assembly frame 7 is divided at the middle portion in the longitudinal direction so as to be held displaceable by following the distorting variation of the floor beam 2.SELECTED DRAWING: Figure 10

Description

  The present invention relates to a test body used for a fire resistance performance test of a floor beam structure and a fire resistance performance test method using the test body.

  The Building Standard Law and the Ordinance for Enforcement of the Law stipulate necessary technical standards for fire and fire resistance depending on the use, scale, location, etc. of the building. It is stipulated that Of these, buildings that are used for residential purposes are constructed in detached houses of a certain size or larger in the fire prevention area specified by the City Planning Act, and in fire prevention areas or semi-fire prevention areas. It is said that a multi-storey apartment building will be a fireproof building.

  A fire-resistant building under the Building Standard Law is a building whose main structural part is a fire-resistant structure or meets a predetermined technical standard regarding the ability to withstand the fire heat of a fire. And, in order to make the main structure part into a fireproof structure, the structure of the part is made the structural method exemplified in the Building Standards Law-related notice (Ministry of Construction Notification No. 1399 in 2000) or by the Minister of Land, Infrastructure, Transport and Tourism. It is supposed to be a certified specification (generally called a certified specification). In addition, when building a building that requires fireproof performance by a new structure / construction method other than the above-mentioned structural methods or certified specifications, testing that the required performance is satisfied by the performance evaluation organization designated by the Ministry of Land, Infrastructure, Transport and Tourism It is necessary to obtain the approval of the Minister of Land, Infrastructure, Transport and Tourism individually from the results of the above.

  For buildings whose main structural parts are steel structures, fire-resistant coating materials such as rock wool are blown or wrapped around pillars and beams made of steel frames to meet the technical standards required for fire-resistant buildings. The conventional general construction method is to prevent the strength of the steel frame from being reduced during a fire. However, this type of refractory construction method has various problems such as workability when spraying refractory coating, etc., environmental pollution problems due to scattering of refractory coating, and restrictions on the storage of peripheral members caused by the thickness of the refractory coating. there were. Therefore, instead of applying a fireproof coating to individual steel frames, by surrounding the steel frame with a fireproof ceiling material, wall material, floor slab, etc., the entire frame is integrally protected from fire heat, A so-called steel membrane fireproof method has been developed and put into practical use (for example, Patent Documents 1 and 2).

JP 10-325204 A (Sekisui House) JP 2000-282598 A (Sekisui Chemical Co., Ltd.)

  For steel frames that have been individually fire-resistant coated, test methods for evaluating their fire resistance performance have been standardized among performance evaluation organizations. For example, in the test of a steel beam used as a floor beam, as shown in FIGS. 11 and 12, a steel beam (test body) 91 having a fireproof coating on the upper portion of a substantially box-shaped heating furnace 90 having an upper opening is provided. It is bridged and its central part is heated by a burner 92 from below. At this time, both ends of the steel beam 91 are extended to the outside of the heating furnace 90 in a state where no fireproof coating is applied, and are supported via pin roller supports 93 provided outside the furnace. The span between both supports is set to 4,000 mm or more, and the heating range is set to 3,000 mm or more. At the time of heating, a degree of stress corresponding to the long-term allowable stress degree of the steel beam 91 is generated from above at the two intermediate portions of the steel beam 91 through a force device 95 such as a hydraulic jack attached to the reaction force frame 94. The vertical load to be loaded is loaded. The pass condition is that the bending deformation amount of the steel beam 91 falls within the specified value until the specified time elapses after the inside of the heating furnace 90 reaches the specified condition.

  The floor beam structure related to the membrane refractory construction method, in which the steel beam is surrounded by a fireproof ceiling material and floor slab, is basically in accordance with the test method for the steel beam itself as described above. It is required to evaluate the fire resistance performance of the entire floor beam structure including the steel beam by the method of measuring the deformation amount. To do so, prepare a specimen with a ceiling base material such as gypsum board, and a floor slab such as an ALC panel on the upper surface of the steel beam. There is a need to. Those ceiling materials and floor slabs are arranged around the ceiling material via a steel frame provided so as to surround the steel beam. The vicinity of both ends of the steel beam is extended to the outside of the frame body, and the extended portion is supported via a pin roller support provided outside the heating furnace in a state without a fireproof coating. At this time, the steel beam bears the weight of the frame itself and the weight of the ceiling materials and floor slabs assembled via the frame. A vertical load corresponding to the allowable stress level is loaded from above by a force device. In this state, the entire test body including the frame body, ceiling material, floor slab, etc. is heated from below, and the amount of deflection deformation of the steel beam itself is measured under predetermined conditions.

  A problem in carrying out such a test is the structure of the frame structure that holds the ceiling material and the floor slab around the steel beam. In other words, when a part of the vertical load to be loaded on the steel beam is transmitted to the frame body, etc., provided so as to surround the steel beam, and internal stress is generated in the members constituting the frame body, the stress is deflected by the steel beam. It acts to resist deformation. Then, it becomes difficult to accurately measure the deformation amount of the steel beam with respect to the loaded load, and the fire resistance performance of the floor beam structure cannot be properly evaluated.

  The present invention has been made paying attention to such problems, and evaluates the fire resistance performance of the floor beam structure according to the membrane fireproof method in which the floor beam is surrounded by a ceiling material or floor slab having fire resistance by a loading heating test. At the time, the fireproof performance test body capable of appropriately grasping the deformation amount of the floor beam without causing stress to resist the deformation of the floor beam in the frame structure supporting the ceiling material, the floor slab, etc. A fire resistance test method using a test body is provided.

  In order to achieve the above-mentioned object, a fireproof performance test body for a floor beam structure according to the present invention includes a floor beam structure in which a lower side of a floor beam is covered with a ceiling material and an upper side of the floor beam is covered with a floor slab. The fire resistance performance of the floor beam structure is evaluated by measuring the amount of deformation of the floor beam when the floor beam structure is heated from below with a vertical load applied to the floor beam. A frame for assembling a ceiling material and a floor slab respectively on the lower side and upper side of the floor beam so as to surround an intermediate portion excluding the vicinity of both ends of the floor beam, The frame is provided over a rectangular region in plan view with the timber as the long axis, and the frame body is disposed above the floor beam and mounted on the floor beam, and is suspended from the suspension frame. The floor being placed on the side of the floor beam And the floor slab is mounted between the floor beam and the floor frame, and an appropriate ceiling base material and a heat insulating material are interposed inside or below the floor frame. As the ceiling material is stretched, a vertical load including the weight of the frame body, the floor slab, and the ceiling material is loaded on the floor beam, and the suspension frame is placed on the floor beam with respect to the floor beam. It is joined through a node that allows displacement in the deflection direction of the beam, and the floor frame is structurally divided at the middle part in the longitudinal direction so that it can be displaced downward following the deflection deformation of the floor beam. The structure with which it was hold | maintained is employ | adopted.

  According to this configuration, the frame structure surrounding the floor beam and the vertical load including the total weight of the floor slab and ceiling held by the frame structure are all loaded on the floor beam, and the floor beam is deformed by the load. It is possible to avoid the stress that resists the frame from being generated on the frame body, so that the portions near both ends of the floor beam extending to the outside of the frame body are bridged between the fulcrum outside the furnace without the fireproof coating. As a result, it becomes possible to perform a bending test under the load heating condition in the same manner as that for a single beam.

  Further, according to the present invention, as a specific aspect of the fireproof performance test body, the suspension frame is disposed in parallel with the floor beam along both long sides of the rectangular region in plan view and is opposed to each other. A pair of end connection beams that are joined to the lower side of both ends of the suspension rail so as to intersect with the suspension rail and connect both ends of the pair of suspension rails, and intersect the suspension rail A pair of intermediate portion connecting beams that are joined to the lower side of the intermediate portion of the suspension rail and connect the intermediate portions of the pair of suspension rails, and the end portion connection beam has a central portion thereof Is mounted on the floor beam via a pin roller support, and the intermediate portion connection beam is joined to the intermediate portion of the suspension rail in a form allowing downward displacement, Center Joined to the upper surface of the floor beam via a strip-shaped connecting strip arranged in a direction in which the core of the floor beam is in the direction of the weak axis, the floor frame is formed between the floor beam and the top surface of each other A strip having a pair of floor support rails that are arranged directly below the suspension rail with the same height, and that both ends of the floor support rail are arranged in a direction in which the core of the floor beam is in the direction of the weak axis Is suspended from both ends of the end connection beam via a connecting band plate, the center portion of the floor support rail is divided, and the vicinity of the divided portion is connected via a beam link orthogonal to the floor beam. Are connected to the side surfaces of the floor beams and joined to the intermediate connection beams via strip-shaped connection strips arranged in a direction in which the center of the floor beam is a weak axis direction, Between the beam and the two floor support rails, a floor slab having a rectangular shape in plan view has a long side extending along the floor beam. A plurality of pieces are mounted in a direction orthogonal to the material center, and a ceiling support frame member is joined to the lower side of the floor support rail along the four sides of the rectangular region in plan view. A configuration is adopted in which the central part of the long side is divided, a field edge is assembled in the frame of the ceiling support frame material, and the ceiling material is stretched on the lower surface of the field edge.

  According to this structure, the fireproof performance test body which concerns on the above-mentioned structure can be manufactured economically with a simple and rational structure.

  Furthermore, in the above-described configuration aspect, as means for joining the both end portions of the intermediate portion connection beam to the intermediate portion of the suspension rail in a form that allows downward displacement, the intermediate portion connection beam and the suspension rail are vertically moved. A long bolt inserted in the direction can be fastened with a nut.

  Further, the fire resistance test method for a floor beam structure according to the present invention uses the fire resistance test body configured as described above to heat the vicinity of both ends of the floor beam extending to the outside of the frame. The floor beam when the test body is heated from below the fireproof performance test specimen in a state where it is bridged between pin roller supports provided outside the furnace and a predetermined vertical load is loaded on an intermediate portion of the floor beam. By measuring the amount of deflection deformation, the fire resistance performance of the floor beam structure is evaluated.

  This test method makes it possible to evaluate the fire resistance performance of a floor beam structure employing a membrane fireproof coating in the same manner as a single beam.

  The fire resistance performance test body of the floor beam structure of the present invention configured as described above has a vertical load that combines the total weight of the frame surrounding the floor beam and the floor slab and ceiling held by the frame. Since it is configured so that stress that is loaded on the beam and resists deformation of the floor beam caused by the load is not generated in the frame, etc., the amount of deformation of the floor beam with respect to the load loaded on the floor beam is appropriately I can grasp it.

  Further, the fire resistance test method for a floor beam structure according to the present invention uses the above-mentioned fire resistance performance test body to bridge the vicinity of both ends of the floor beam extending to the outside of the frame structure between fulcrums outside the furnace. By doing so, it is possible to perform a floor beam bending test under the load heating condition in the same way as a single beam, so that it becomes possible to appropriately evaluate the fire resistance performance of the membrane fire-resistant floor beam structure .

It is a partially exploded top view of the fireproof performance test body of the floor beam structure according to the embodiment of the present invention. It is a side view by the side of the long side of the test body. It is a side view by the side of the short side of the test body. It is a partially exploded bottom view of the test body. It is AA sectional drawing of the test body. It is BB sectional drawing of the test body. It is a decomposition explanatory view of the main components in the AA section of the test body. It is a decomposition explanatory view of the main components in the BB section of the test body. It is a side view which shows the deformation | transformation state (before a deformation | transformation) at the time of the load heating of the test body, (a) is a floor beam, (b) is a figure which shows the state of the long side part of a frame. It is a side view which shows the deformation | transformation state (after a deformation | transformation) at the time of the load heating of the test body, (a) is a floor beam, (b) is a figure which shows the state of the long side part of a frame. It is longitudinal direction sectional drawing of the test apparatus used for the fireproof performance test of a floor beam. It is a transversal direction sectional view of the test device.

  Embodiments of the present invention will be described below with reference to the drawings.

  1-8 has shown the structure of each part of the fireproof performance test body of the floor beam structure which concerns on embodiment of this invention. The fireproof performance test body (hereinafter simply referred to as “test body”) 1 has a floor beam 2 made of a steel beam covered with a ceiling material 3 having fire resistance, and an upper side of the floor beam 2 is covered. With respect to the steel membrane fireproof floor beam structure covered by the floor slab 4 having fire resistance, the entire floor beam structure is heated from below while a predetermined vertical load is loaded on the floor beam 2, and the floor at that time This is for evaluating the fire resistance performance of the floor beam structure by measuring the deflection amount of the beam 2.

  In the illustrated embodiment, an H-section steel that is not provided with a special fireproof coating is used as the floor beam 2 to be measured for the deflection amount. The cross-sectional dimensions of the H-shaped steel shown are a flange width of 125 mm and a web height of 250 mm. The total length of the floor beam 2 is, for example, about 5,500 mm. This is spanned on the upper part of the heating furnace 90 as shown in FIGS. 11 and 12, and both ends extending to the outside of the heating furnace 90 are outside the furnace. For example, a span of 5,100 mm is supported through the provided pin roller support 93. The pin roller support 93 sandwiches a round steel bar between the base portion and the floor beam 2 to allow the floor beam 2 to rotate in the vertical direction, and the base portion has a plurality of rolling rollers. And a support mechanism configured to allow horizontal movement of the floor beam 2.

  At two locations close to the center of the top surface of the floor beam 2, a pressing jig 21 is attached with a predetermined interval. A predetermined vertical load is loaded on the applying jig 21 from above via an applying device 95 such as a hydraulic jack. The predetermined vertical load is a vertical load that causes a stress level corresponding to the long-term allowable stress level of the floor beam 2 to be generated in the main cross section of the floor beam 2, and the total amount is a frame, ceiling material 3, floor, which will be described later. Calculated including the total weight of plate 4 and other components. And the center part in the length direction of the floor beam 2, the several places including the position of the jig 21 for a force, and the deflection amount at the time of a heating will be measured.

  In addition, a suspension plate 22 for lifting the test body 1 with a crane or the like when the test body 1 is installed in the heating furnace 90 is welded to the top surfaces of both ends of the floor beam 2.

  The floor beam 2 is mounted on the upper opening of the heating furnace 90 in a state where a certain range of the lower side and the upper side thereof is covered with the ceiling material 3 and the floor slab 4. In order to hold the ceiling material 3 and the floor slab 4 around the floor beam 2, the frame 5 made of steel surrounds the middle part except for the vicinity of both ends of the floor beam 2, and the core of the floor beam 2 is The long axis is assembled so as to cover a rectangular area in plan view. The dimensions of the long side and the short side of the region correspond to the size of the upper opening of the heating furnace 90, and are 4,250 mm × 1,900 mm in the illustrated embodiment.

  The frame body 5 is arranged above the floor beam 2 and suspended on the floor beam 2, and the floor assembly suspended on the suspension frame 6 and disposed on the side of the floor beam 2. And a frame 7.

  The suspension frame 6 is disposed in parallel with the floor beam 2 along both long sides of the above-described rectangular area in plan view, and a pair of suspension rails 61 facing each other and the suspension rail 61 so as to intersect the suspension rail 61. A pair of end connection beams 62 that are joined to the lower side of both ends of the pair of suspension rails 61 to connect the ends of the pair of suspension rails 61, and below the intermediate portion of the suspension rail 61 so as to intersect the suspension rail 61. A pair of intermediate part connection beams 63 that are joined and connect the intermediate parts of the pair of suspension rails 61 are combined.

  The suspension rail 61, the end connection beam 62, and the intermediate connection beam 63 are all formed using grooved steel having the same cross section, and bolts and nuts are fastened in the vertical direction by connecting the flanges at the intersecting points. Are joined together. However, as for the joint portion between the both end portions of the intermediate portion connecting beam 63 and the intermediate portion of the suspension rail 61, a dimensioned bolt having a sufficient length is used as a bolt for inserting each flange. By loosening the nut screwed to the dimension bolt 64 at the time of the test, the intermediate portion connecting beam 63 and the suspension rail 61 can be brought into and out of contact within a certain range.

  A central portion of the end connecting beam 62 is placed on the floor beam 2 via a pin roller support 65. The pin roller bearing 65 is a support mechanism configured to allow the rotation and horizontal movement of the nodes as in the case of the outside pin roller bearing 93 that supports both ends of the floor beam 2. The roller bearing 93 is assembled between the floor beam 2 and the end connecting beam 62 in a vertically inverted form. It should be noted that in the preparation stage from the time when the test body 1 is lifted by a crane and installed in the heating furnace 90, appropriate auxiliary members (not shown) or the like are connected to each other so that the end connection beam 62 and the floor beam 2 are not separated. You may connect with.

  The center part of the intermediate part connection beam 63 is joined to the upper surface of the floor beam 2 via a strip-like connection strip A23 made of flat steel. The connection strip A23 is welded so as to rise on the upper surface of the floor beam 2 in a posture orthogonal to the material center of the floor beam 2, and the upper portion thereof is fastened to the web of the intermediate connection beam 63 with bolts and nuts. According to this joining mode, the connecting strip A23 is attached with its weak axis direction (thickness direction of the flat steel) directed toward the material center direction (bending direction) of the floor beam 2, so that the floor beam 2 undergoes bending deformation. When this occurs, the connecting strip A23 will also easily deform without resisting deformation of the floor beam 2.

  The floor assembly frame 7 includes a pair of floor support rails 71 that are arranged directly below the suspension rail 61 with the height of the top surfaces of the floor beam 2 and each other being aligned. The floor support rail 71 is formed using channel steel having a web height comparable to that of the floor beam 2. Both ends of the floor support rail 71 are suspended from both ends of the end connection beam 62 via a strip-shaped connection strip B72 made of flat steel. This connection strip B72 is welded to the end surface of the floor support rail 71 in a posture perpendicular to the core of the floor support rail 71 and extends upward, and the upper part thereof is connected to the web of the end connection beam 62 by bolts and nuts. It is worn.

  The floor support rail 71 is divided at the center in the length direction, and the vicinity of the divided portion is connected to the floor beam 2 and the intermediate portion connection beam 63 of the suspension frame 6. The floor beam 2 is connected to the floor beam 2 via a beam link 73 arranged so as to be orthogonal to the floor beam 2. A lip-shaped channel steel is used for the beam tether 73, and connecting plates 74 attached to both ends of the web are stiffeners 24 attached to the side surfaces of the floor beam 2 and the floor support rail 71, respectively. Bolts and nuts are respectively attached to 75. Further, a strip-shaped connection strip C76 made of flat steel is welded to the intermediate connection beam 63 so as to rise on the upper surface of the floor support rail 71 in a posture orthogonal to the core of the floor support rail 71. The upper part of the intermediate part connecting beam 63 is fastened to the web of the intermediate part connecting beam 63 by bolts and nuts.

  A plurality of floor slabs 4 are mounted between the floor beam 2 and both floor support rails 71. The floor slab 4 according to the exemplary embodiment is an ALC (foamed lightweight concrete) panel. The floor slab 4 has a long rectangular planar shape, and its long side is perpendicular to the material center of the floor beam 2 and is arranged with a slight gap between adjacent portions. Both ends of the floor slab 4 are attached to the floor beam 2 and the floor support rail 71 via, for example, a floor slab mounting bracket 41 that can sandwich the upper flange of the floor beam 2 and the floor support rail 71.

  Below the floor support rail 71, a ceiling support frame member 77 serving as an outer peripheral base for forming a ceiling below the floor beam 2 is joined so as to surround the above-described rectangular region in plan view. The ceiling support frame member 77 is formed using, for example, unequal side angle steel, and the narrow piece is welded to the lower surface of the floor support rail 71 with the wide piece facing downward. Among the long and short four sides constituting the ceiling support frame member 77, the central part of the long side attached along the lower side of the floor support rail 71 is divided at the central part in the length direction, like the floor support rail 71. Yes.

  On the inner side of the area surrounded by the ceiling support frame member 77, there are a ceiling runner 31 attached to the inner side surface of the wide piece of the ceiling support frame member 77, a field edge receiving bracket 32 attached to the beam tether 73, Several field edges 34 are assembled via a field edge receiver 33 attached to the field edge receiving bracket 32 and suspended in parallel with the beam tether 73. Further, a field edge vibration isolating member 35 may be attached to the upper surface of the field edge 34 so as to intersect with the field edges 34. The ceiling runner 31, the field edge receiver 33, the field edge 34, and the field edge vibration isolating member 35 are made of thin lightweight steel materials that can be easily deformed with the deformation of the floor beam 2.

  Then, a heat insulating material 36 (or a sound absorbing material) made of, for example, an inorganic fiber-based heat insulating mat or the like is laid on the entire surface of the rectangular region surrounded by the ceiling support frame material 77 on the field edge 34. In addition, a ceiling material 3 made of a reinforced gypsum board or the like is stretched over the entire surface of the rectangular region with a moisture-proof sheet 37 and the like interposed therebetween.

  According to the test body 1 configured as described above, the weight of the frame body 5 constituted by the suspension frame 6 and the floor frame 7 is such that the end connection beam 62 and the intermediate connection beam 63 of the suspension frame 6 are connected to the floor. It is loaded on the floor beam 2 via each joint with the beam 2. Further, the weight of the floor slab 4 mounted between the floor beam 2 and the floor frame 7 is approximately half directly loaded on the floor beam 2 and the other approximately half is indirectly via the frame 5. In particular, it is loaded on the floor beam 2. The weight of the entire ceiling including the ceiling base material such as the field edge receiver 33 and the field edge 34 assembled below the floor frame 7 and the heat insulating material 36 is also loaded on the floor beam 2 indirectly via the frame 5. Is done. Accordingly, the frame 5 surrounding the floor beam 2 and the vertical load including the total weight of the floor slab 4 and the ceiling held by the frame 5 are all loaded on the floor beam 2 and the outside of the frame 5 By bending the portion near the both ends of the floor beam 2 extended to between the fulcrums outside the furnace without the fireproof coating, the bending test under the loading heating condition can be performed in the same manner as the single beam.

  The state before and after deformation of the floor beam 2 and the frame 5 during loading heating is shown in comparison with FIG. 9 and FIG. In each figure, (a) shows the floor beam 2 and (b) shows the long side portion of the frame 5.

  The floor beam 2 itself is supported at two ends by pin roller supports 93 that allow rotation and horizontal movement of the nodes, and two connecting strips that join the intermediate connecting beam 63 to the intermediate portion thereof. When a predetermined load is loaded via A23 and the two jigs 21 for applying force, downward bending deformation occurs. At this time, since the end connecting beam 62 disposed at the end of the suspension frame 6 is loaded on the floor beam 2 via the pin roller support 65, the end of the suspension frame 6 is bent by the floor beam 2. Does not constrain deformation.

  On the other hand, in the portion along the outer long side of the frame 5, the nuts of the long bolts 64 that connect the both ends of the intermediate connection beam 63 and the suspension rail 61 are loosened, and the intermediate connection beam 63 and the suspension rail are loosened. 61 is connected so that contact and separation are possible. As a result, the intermediate connection beam 63 is held in a state where it can be displaced downward following the bending deformation of the floor beam 2, so that the suspension rail 61 of the suspension frame 6 bears the load loaded on the floor beam 2. Disappear.

  Further, both end portions of the intermediate connection beam 63 are joined to the floor support rail 71 constituting the floor assembly frame 7 via the connection strip B72, but the floor support rail 71 is divided at the central portion. The floor support rail 71 bends in a V shape in a side view as the intermediate portion connecting beam 63 is displaced downward. At this time, the connection strip A23 that joins the center portion of the intermediate connection beam 63 to the floor beam 2, the connection strip C76 that joins both ends of the intermediate connection beam 63 to the floor support rail 71, and the floor support rail 71 Any of the connecting strips B72 that join both ends to the suspension frame 6 does not resist bending deformation of the floor beam 2 or bending of the floor support rail 71, so that the weak axis direction of each strip is the long side of the frame 5 It is attached toward the direction (the direction of the core of the floor beam 2). Therefore, no stress that resists bending deformation of the floor beam 2 is generated in the connecting strips A23, B72, and C76.

  Further, when the floor support rail 71 is bent, the beam joint 73 connecting the floor support rail 71 and the floor beam 2 is also displaced downward together. At this time, the torsional deformation is slightly generated in the connecting plates 74 attached to both ends of the beam joint 73, but the rigidity thereof is far smaller than the bending rigidity of the floor beam 2, so that these connecting plates 74 are connected to the floor. The load borne for the bending deformation of the beam 2 is also very small.

  Further, the floor slab 4 mounted between the floor beam 2 and the floor support rail 71 is also arranged such that its long side is orthogonal to the material center of the floor beam 2 and a slight gap is formed between them. Therefore, no stress that resists bending deformation of the floor beam 2 is generated. Since the base member, the heat insulating material 36, the ceiling material 3 and the like constituting the ceiling do not have rigidity enough to resist bending deformation of the floor beam 2, their load burden can be ignored.

  With these configurations, no stress that resists bending deformation of the floor beam 2 is generated on the frame 5, the floor slab 4, the ceiling, etc. surrounding the floor beam 2, and the floor beam 2 is subjected to simple bending according to the loaded load. Deflection occurs, and it becomes possible to appropriately measure and evaluate the fire resistance performance of the floor beam structure employing the membrane fire resistance method.

  Note that if the floor beam 2 or the frame body 5 is greatly deformed and damaged during the test, or a part of the floor beam 2 or the frame body 5 falls off, the test body 1 may not be safely removed from the furnace. Therefore, when the deformation of the floor frame 7 (bending of the floor support rail 71) exceeds a certain limit, both ends of the intermediate connection beam 63 and the suspension rail 61 are connected so that a load is applied to the suspension frame 6. By adjusting the nut screwing position of the long bolt 64 in advance, the long bolt 64 can act as a stopper against excessive deformation of the floor frame 7.

  The technical scope of the present invention should not be construed as being limited by the illustrated embodiments, but should be conceptually interpreted based on the description of the claims. In carrying out the present invention, it is of course possible to modify the shape and arrangement of the component members and the form of joining of the component members to some extent as long as substantially the same effects as the exemplary embodiments can be obtained. It is.

  The present invention has been conceived mainly for the purpose of evaluating the performance of a floor beam structure according to a so-called steel membrane fireproofing method in which a steel beam is surrounded by a ceiling material 3 and a floor slab 4. Steel beams with fireproof coatings individually, etc., fire-resistant ceiling materials, composite floor beam structures combining floor slabs, fire-resistant wooden beams or composite beams of wood and steel frames It can also be applied to fire resistance test of floor beam structures etc. related to wooden membrane fireproof construction method combining ceiling material and floor slab.

DESCRIPTION OF SYMBOLS 1 Specimen 2 Floor beam 21 Force jig 22 Suspension plate 23 Connection strip A
24 Stiffener 3 Ceiling material 31 Ceiling runner 32 Field edge receiving suspension bracket 33 Field edge receiving 34 Field edge 35 Field edge vibration isolating member 36 Heat insulating material 4 Moisture proof sheet 4 Floor slab 41 Floor slab mounting bracket 5 Frame 6 Suspension frame 61 Suspension rail 62 End Connection Beam 63 Intermediate Connection Beam 64 Long Bolt 65 Pin Roller Bearing 7 Floor Assembly Frame 71 Floor Support Rail 72 Connection Band B
73 Beam connection 74 Connection plate 75 Stiffener 76 Connection strip C
77 Ceiling support frame 90 Heating furnace 91 Steel beam (test body)
92 Burner 93 Pin roller support 94 Reaction force frame 95 Force device

Claims (4)

With respect to a floor beam structure in which a lower side of the floor beam is covered with a ceiling material and an upper side of the floor beam is covered with a floor slab, the floor beam structure is viewed from below in a state where a vertical load is loaded on the floor beam. By measuring the amount of deflection deformation of the floor beam when heated, it is a test body for evaluating the fire resistance performance of the floor beam structure,
A plane for assembling a ceiling material and a floor slab on the lower side and the upper side of the floor beam so as to surround an intermediate portion excluding the vicinity of both ends of the floor beam, and a plane having the longitudinal axis of the core of the floor beam Provided over a rectangular area,
The frame body is a suspension frame disposed above the floor beam and mounted on the floor beam, and a floor assembly frame suspended on the suspension frame and disposed on the side of the floor beam. And comprising
The floor slab is mounted between the floor beam and the floor frame, and a ceiling material is stretched on the inner side or the lower side of the floor frame through an appropriate ceiling base material and heat insulating material. A vertical load including the weight of the frame body, the floor slab and the ceiling material is loaded on the floor beam,
The suspension frame is joined to the floor beam via a node that allows displacement in the deflection direction of the floor beam,
The floor frame structure is structurally divided at the middle part in the longitudinal direction, and is held so that it can be displaced downward following the flexural deformation of the floor beam. Test specimen. In the fireproof performance test body of the floor beam structure according to claim 1,
The suspension frame includes a pair of suspension rails arranged parallel to the floor beam along both long sides of the rectangular region in plan view, and opposite ends of the suspension rail so as to cross the suspension rail. A pair of end connection beams which are joined to the lower side and connect both ends of the pair of suspension rails, and are joined to the lower side of the intermediate portion of the suspension rail so as to intersect the suspension rails. A pair of intermediate part connecting beams for connecting the intermediate parts of the suspension rails,
The center of the end connection beam is mounted on the floor beam via a pin roller support,
The both ends of the intermediate portion connecting beam are joined to the intermediate portion of the suspension rail in a form that allows downward displacement, and the center portion thereof is oriented so that the material center of the floor beam is the weak axis direction. It is joined to the upper surface of the floor beam via a strip-shaped connecting strip disposed,
The floor frame includes a pair of floor support rails arranged directly below the suspension rail with the floor beams and the height of each top surface aligned.
Both ends of the floor support rail are suspended from both ends of the end connection beam via a strip-shaped connection strip arranged in a direction in which the center of the floor beam is a weak axis direction,
The center portion of the floor support rail is divided, and the vicinity of the divided portion is connected to the side surface of the floor beam via a beam link orthogonal to the floor beam, and the center of the floor beam is weakened. Joined to the intermediate connection beam through a strip-shaped connection strip arranged in the axial direction,
Between the floor beam and the both floor support rails, a floor slab having a rectangular shape in plan view is mounted in a plurality of pieces in a direction in which the long side is orthogonal to the material center of the floor beam,
A ceiling support frame member is joined to the lower side of the floor support rail along the four sides of the rectangular region in plan view,
The ceiling support frame material is divided at the center of both long sides,
A field edge is assembled in the frame of the ceiling support frame member,
The flooring structure fireproof performance test body, wherein the ceiling material is stretched on the lower surface of the field edge.
In the fireproof performance test body of the floor beam structure according to claim 2,
Means for joining both ends of the intermediate connection beam to the intermediate portion of the suspension rail in a form that allows downward displacement is a long bolt inserted vertically into the intermediate connection beam and the suspension rail. A fireproof performance test piece for a floor beam structure, characterized by being attached by nuts. A test method for evaluating fire resistance performance of a floor beam structure in which a lower side of a floor beam is covered with a ceiling material and an upper side of the floor beam is covered with a floor slab,
The fireproof performance test body used in the test method is:
A plane for assembling a ceiling material and a floor slab on the lower side and the upper side of the floor beam so as to surround an intermediate portion excluding the vicinity of both ends of the floor beam, and a plane having the longitudinal axis of the core of the floor beam Provided over a rectangular area,
The frame body is a suspension frame disposed above the floor beam and mounted on the floor beam, and a floor assembly frame suspended on the suspension frame and disposed on the side of the floor beam. And comprising
The floor slab is mounted between the floor beam and the floor frame, and a ceiling material is stretched on the inner side or the lower side of the floor frame through an appropriate ceiling base material and heat insulating material. A vertical load including the weight of the frame body, the floor slab and the ceiling material is loaded on the floor beam,
The suspension frame is joined to the floor beam via a node that allows displacement in the deflection direction of the floor beam,
The floor frame is structured to be structurally divided at the middle in the longitudinal direction, and held so that it can be displaced downward following the flexural deformation of the floor beam,
In the state where a portion near the both ends of the floor beam extending to the outside of the frame is bridged between pin roller supports provided outside the heating furnace, and a predetermined vertical load is loaded on the middle portion of the floor beam, The fire resistance performance of the floor beam structure is evaluated by measuring the deflection deformation amount of the floor beam when the test body is heated from below the fire resistance performance test body. Fire resistance test method.

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