A fall-prevention concrete floor slab, connection joint and its construction method

Abstract

A fall-prevention concrete floor slab, its connection nodes, and their construction method are disclosed. The slab includes a precast section, which comprises a lower concrete base plate and precast steel components. The precast steel components include a steel truss, lower transverse reinforcing bars, and lower steel strand anchors. The steel truss includes longitudinal upper and lower reinforcing bars and web bars connecting the two. The lower steel strand anchors are located on both longitudinal sides of the concrete base plate and connected to the lower reinforcing mesh. The outer ends of the lower steel strand anchors extend beyond the longitudinal ends of the concrete base plate. This invention innovatively designs steel strand anchors and integrates them into existing composite floor slab and foundation floor slab structures, significantly improving the stress and connection methods of existing floor slab structures. It offers advantages such as high load-bearing capacity, facilitates floor slab construction, and improves the construction speed and quality of concrete slabs, thus meeting the load-bearing requirements of floor slabs.

Description

Technical Field

[0001] This invention pertains to precast concrete components, specifically a prestressed concrete floor slab, connection joint, and construction method thereof. Background Technology

[0002] Currently, precast truss reinforced concrete composite floor slabs are the mainstream technology for precast floor slabs. However, in the end stage of the precast concrete slab, when connecting to beams, the bottom reinforcement is generally connected to the beams or walls using additional reinforcement. Although this technology is convenient for construction, it greatly reduces the effective height at the slab ends, resulting in a significant decrease in the flexural strength of the slab ends, making them prone to cracking, and even potentially causing failure at the joint area, posing a risk of collapse.

[0003] Meanwhile, if the existing precast floor slabs have pre-reserved reinforcing bars at the ends, it is extremely inconvenient to transport them. The option is to cut the reinforcing bars before transportation and then carry out secondary processing on site to add additional reinforcing bars, which is time-consuming and labor-intensive.

[0004] Therefore, finding a precast floor slab that can achieve good load-bearing performance while being easy to construct and transport is a major challenge for the project. Summary of the Invention

[0005] The purpose of this invention is to provide a fall-prevention concrete floor slab, connection nodes, and their construction method. It addresses the technical problems of precast truss reinforced concrete composite floor slabs where the use of additional reinforcing bars in the lower reinforcement reduces the effective height at the slab ends, leading to decreased bending resistance and cracking at the slab ends, and posing a risk of collapse if the connection area is damaged.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A fall-prevention concrete floor slab includes a slab body, the slab body comprising a precast section, the precast section including a lower concrete base plate and precast steel components, the precast steel components including a steel truss, lower transverse reinforcing bars, and lower steel strand anchors.

[0008] The steel truss includes longitudinal top bars, longitudinal bottom bars, and web bars connecting the two. The bottom bars are located within the concrete slab, and the lower transverse bars are fixedly connected to the bottom bars to form a lower steel mesh.

[0009] The top reinforcement bars of the truss are parallel to the bottom reinforcement bars of the truss and are located above the concrete base plate. The top reinforcement bars and the bottom reinforcement bars of the truss are connected by truss web reinforcement bars. The bottom of the truss web reinforcement bars is embedded in the concrete base plate, and the upper part of the truss web reinforcement bars extends out of the concrete base plate.

[0010] The lower steel strand anchor is installed on both sides of the concrete substrate and connected to the lower steel mesh. The outer end of the lower steel strand anchor extends out of the longitudinal end of the concrete substrate.

[0011] The lower steel strand anchor is a section of steel strand set at the end along the longitudinal direction of the floor slab.

[0012] The lower steel strand anchor is a whole steel strand installed along the longitudinal length of the floor slab, and the steel strand is a prestressed steel strand.

[0013] The portion of the lower steel strand anchor extending out of the concrete substrate can be one or more of the following: straight type, straight type with end anchoring reinforcement, curved type, curved type with end anchoring reinforcement, and collar type.

[0014] The lower steel strand anchor is connected to the lower steel mesh by lap splicing, welding or sleeve connection, and the lower steel strand anchor is close to the side of the lower truss reinforcement.

[0015] The truss reinforcement is made of steel bars or structural steel components.

[0016] A fall-prevention concrete floor slab includes a precast section and a composite cast-in-place section. The composite cast-in-place section includes cast-in-place reinforcement bars and cast-in-place concrete. The cast-in-place reinforcement bars include upper transverse reinforcement bars and upper steel strand anchors.

[0017] The upper transverse reinforcing bars are connected to the truss top reinforcing bars to form an upper reinforcing mesh. The cast-in-place concrete is poured to the upper side of the concrete base plate and covers the cast-in-place reinforcing bars and the precast steel components. The exposed portions of the precast steel components on the upper side of the concrete base plate form a concrete composite slab to prevent falls.

[0018] The upper steel strand anchor is installed on both sides of the cast-in-place concrete and connected to the upper steel mesh. The outer end of the upper steel strand anchor extends out of the longitudinal end of the cast-in-place concrete.

[0019] The upper steel strand anchor is a section of steel strand set at the end along the longitudinal direction of the floor slab.

[0020] The upper steel strand anchor is a whole steel strand installed along the longitudinal length of the floor slab, and the steel strand is a prestressed steel strand.

[0021] The portion of the upper steel strand anchor extending out of the concrete substrate can be one or more of the following: straight type, straight type with end anchoring reinforcement, curved type, curved type with end anchoring reinforcement, and collar type.

[0022] The connection between the upper steel strand anchor and the upper steel mesh is by lap splicing, welding or sleeve connection, and the upper steel strand anchor is close to the side of the upper reinforcement of the truss.

[0023] A fall-prevention concrete floor slab includes a slab body comprising a lower precast slab, an upper precast slab, a central connecting rib, and a central hollow hole. The lower precast slab includes a lower slab reinforcing mesh and lower slab concrete. The lower slab reinforcing mesh includes lower slab longitudinal bars and lower slab transverse bars. Lower steel strand anchors are fixedly connected to the longitudinal ends of the lower slab reinforcing mesh. The lower slab concrete covers the lower slab reinforcing mesh and the lower steel strand anchors, with both ends of the lower steel strand anchors extending beyond the longitudinal ends of the lower slab concrete.

[0024] The upper precast slab includes an upper slab steel mesh and upper slab concrete. The upper slab steel mesh includes upper slab longitudinal bars and upper slab transverse bars. The longitudinal ends of the upper slab steel mesh are also fixedly connected to upper steel strand anchors. The upper slab concrete covers the upper slab steel mesh and upper steel strand anchors. The two ends of the upper steel strand anchors extend beyond the longitudinal ends of the upper slab concrete.

[0025] The central connecting ribs and central hollow holes are alternately arranged between the upper precast slab and the lower precast slab. The central connecting ribs are longitudinally spaced ribs that connect the upper precast slab and the lower precast slab.

[0026] The hollow hole in the middle is filled with a filler, which is plastic, rubber, sponge, or a combination thereof.

[0027] The upper steel strand anchor is a section of steel strand set at the end along the longitudinal direction of the floor slab or a whole steel strand set along the longitudinal direction of the floor slab. The whole steel strand is a prestressed steel strand. The part of the upper steel strand anchor extending out of the concrete substrate is straight and / or forms a collar. The connection between the upper steel strand anchor and the upper slab reinforcement mesh is lapped, welded or sleeved. The upper steel strand anchor is close to the side of the upper slab longitudinal reinforcement.

[0028] The lower steel strand anchor is a section of steel strand set at the end along the longitudinal direction of the floor slab or a whole steel strand set along the longitudinal direction of the floor slab. The whole steel strand is a prestressed steel strand. The part of the lower steel strand anchor extending out of the concrete substrate can be one or more of the following: straight type, straight type with end anchoring reinforcement, curved type, curved type with end anchoring reinforcement, and collar type. The connection between the lower steel strand anchor and the lower slab reinforcement mesh is lapped, welded, or sleeved. The lower steel strand anchor is close to the side of the lower slab longitudinal reinforcement.

[0029] A connection node for a fall-prevention concrete floor slab includes the aforementioned slab body and a vertical member fixedly connected to the slab body. The portion of the lower steel strand anchor extending out of the slab body is anchored into the vertical member, and the portion of the upper steel strand anchor extending out of the slab body is embedded in the vertical member. The vertical member is a beam and / or a wall, and the extended steel strands are integrally formed with the concrete or grout in the node area.

[0030] A construction method for fall-prevention concrete floor slabs, the construction steps are as follows:

[0031] Step 1: Prefabricate the steel components in the factory;

[0032] Step 2: Erect the formwork for the floor slab;

[0033] Step 3: Lay the steel truss, lower steel strand anchors, and lower layer of transverse reinforcement;

[0034] Step 4: Pour concrete to form a concrete base plate;

[0035] Step 5: Cure the concrete to the predetermined strength.

[0036] After step three, add: tensioning the steel strand anchors and applying prestress;

[0037] Add the following step after step five: cut off the lower steel strand anchor.

[0038] A construction method for fall-prevention concrete floor slabs, the construction steps are as follows:

[0039] Step 1: Prefabricate the steel components in the factory;

[0040] Step 2: Erect the formwork for the floor slab;

[0041] Step 3: Lay the steel truss, lower steel strand anchors, and lower layer of transverse reinforcement;

[0042] Step 4: Pour concrete to form a concrete base plate;

[0043] Step 5: Cure the concrete to the predetermined strength;

[0044] Step six: After the prefabricated components are transported to the site, they are hoisted into place;

[0045] Step 7: Lay the upper layer of transverse reinforcing bars and upper steel strand anchors;

[0046] Step 8: Erect the formwork for the cast-in-place section;

[0047] Step nine: Constructing composite floor slabs by pouring in-situ concrete;

[0048] Step 10: Cure the concrete to the predetermined strength.

[0049] After step three, add: tensioning the steel strand anchors and applying prestress;

[0050] Add the following step after step five: cut off the lower steel strand anchor.

[0051] After step seven, add: tensioning the steel strand anchors and applying prestress;

[0052] Add the following step after step nine: cut the upper steel strand anchor.

[0053] A construction method for fall-prevention concrete floor slabs, the construction steps are as follows:

[0054] Step 1: The factory manufactures the lower slab reinforcement mesh, lower steel strand anchors, upper slab reinforcement mesh, and upper steel strand anchors;

[0055] Step 2: Erect the formwork for the floor slab;

[0056] Step 3: Connect the lower plate steel mesh and lower steel strand anchors, as well as the upper plate steel mesh and upper steel strand anchors, into a whole in sequence. First, lay the lower plate steel mesh and lower steel strand anchors, then add the inner mold with the hollow hole in the middle, and finally lay the upper plate steel mesh and upper steel strand anchors.

[0057] Step 4: Pour concrete to form the slab;

[0058] Step 5: Cure the concrete to the predetermined strength;

[0059] Step 6: Remove the inner mold;

[0060] After step three, add the following steps: tension the lower steel strand anchor and apply prestress; tension the upper steel strand anchor and apply prestress.

[0061] After step five, add: cut off the lower steel strand anchor and cut off the upper steel strand anchor.

[0062] Compared with the prior art, the present invention has the following features and beneficial effects:

[0063] This invention innovatively designs a steel strand anchor and integrates it into existing composite floor slabs and foundation floor slab structures. The length of the steel strand extending out of the slab is similar to that of existing reinforcing bars, and can be limited to a length of 5d. This significantly improves the stress and connection methods of existing floor slab structures, has the advantage of high load-bearing capacity, and facilitates floor slab construction, improving the construction speed and quality of concrete slabs, and can meet the load-bearing capacity requirements of floor slabs.

[0064] This invention improves the force transmission efficiency at the ends of floor slabs, ensuring continuous force transmission:

[0065] 1. The anchoring wire rope and the bottom reinforcement of the truss can work together to significantly improve the bending bearing capacity at the support, by more than 30%.

[0066] Second, improve the bending bearing capacity and overall in-plane bending stiffness of the anti-fall concrete floor slab, so that the entire structure can be deformed as a whole, preventing the structure from being broken apart piecemeal.

[0067] Third, improving the overall integrity of the structure can effectively prevent the collapse of the massive concrete slab at the epicenter.

[0068] IV. Facilitates construction and replacement, effectively improving construction speed;

[0069] Fifth, steel strands are more flexible and easier to transport than steel bars.

[0070] Sixth, it can be produced on a large industrial scale.

[0071] 7. The floor slab can be made into a hollow structure, which reduces the weight of the precast concrete slab.

[0072] 8. Extending the longitudinal steel bars at the top of the precast concrete can enhance the anchoring or continuous force transmission effect at the top. Attached Figure Description

[0073] The present invention will now be described in further detail with reference to the accompanying drawings.

[0074] Figure 1 This is a schematic diagram of the structure of the plate body in Embodiment 1 of the present invention.

[0075] Figure 2 This is a schematic diagram of the structure of the plate body in Embodiment 2 of the present invention.

[0076] Figure 3 yes Figure 1 or Figure 2 A schematic diagram of the cross-sectional structure of the concrete substrate.

[0077] Figure 4 This is a schematic diagram of the structure of the plate body in Embodiment 3 of the present invention.

[0078] Figure 5 This is a schematic diagram of the structure of the plate body in Embodiment 4 of the present invention.

[0079] Figure 6 yes Figure 5 A schematic diagram of the cross-sectional structure of the concrete substrate.

[0080] Figure 7 This is a schematic diagram of the structure of the plate body in Embodiment 5 of the present invention.

[0081] Figure 8 This is a schematic diagram of the structure of the plate body in Embodiment Six of the present invention.

[0082] Figure 9 yes Figure 8 Cross-sectional structural diagram.

[0083] Figure 10 This is a schematic diagram of the structure of embodiment seven of the present invention.

[0084] Figure 11 yes Figure 10 Cross-sectional structural diagram.

[0085] Figure 12 This is a schematic diagram of the structure of embodiment eight of the present invention.

[0086] Figure 13 This is a schematic diagram of the connection node structure of the present invention.

[0087] Figure 14 It is a straight type with an anchoring reinforcement at the end, as described in Embodiment 1 of the present invention.

[0088] Figure 15 In Embodiment 1 of the present invention, the end is curved.

[0089] Figure 16 It is a curved shape with an anchoring reinforcement at the end, as described in Embodiment 1 of the present invention.

[0090] Reference numerals: 1 - Lower transverse reinforcement, 2 - Lower steel strand anchor, 3 - Truss top reinforcement, 4 - Truss bottom reinforcement, 5 - Concrete base plate, 6 - Truss web reinforcement, 7 - Cast-in-place concrete, 8 - Upper transverse reinforcement, 9 - Upper steel strand anchor, 10 - Lower slab concrete, 11 - Lower slab longitudinal reinforcement, 12 - Lower slab transverse reinforcement, 13 - Upper slab concrete, 14 - Upper slab longitudinal reinforcement, 15 - Upper slab transverse reinforcement, 16 - Middle connecting rib, 17 - Middle hollow hole, 18 - Filler, 19 - Vertical member, 20 - Anchorage reinforcement. Detailed Implementation

[0091] See Example 1 Figure 1 and Figure 3 As shown.

[0092] A fall-prevention concrete floor slab includes a slab body, the slab body including a precast section, the precast section including a lower concrete base plate 5 and a precast steel component, the precast steel component including a steel truss, a lower transverse steel bar 1 and a lower steel strand anchor 2.

[0093] The steel truss includes longitudinal upper truss bars 3, longitudinal lower truss bars 4, and truss web bars connecting the two. The lower truss bars 4 are located within the concrete substrate, and the lower transverse steel bars are fixedly connected to the lower truss bars 4 to form a lower steel mesh.

[0094] The upper truss bar 3 is parallel to the lower truss bar 4. The upper truss bar 3 is located above the concrete base plate 5. The upper truss bar 3 and the lower truss bar 4 are connected by the truss web bar 6. The bottom of the truss web bar 6 is embedded in the concrete base plate 5, and the upper part of the truss web bar 6 extends out of the concrete base plate 5.

[0095] The lower steel strand anchor 2 is disposed on both sides of the concrete substrate 5 and connected to the lower steel mesh. The outer end of the lower steel strand anchor 2 extends out of the longitudinal end of the concrete substrate 5.

[0096] The lower steel strand anchor 2 is a section of steel strand set at the end along the longitudinal direction of the floor slab. The number of steel strands is twice the number of the lower truss bars. The steel strands are set in pairs on the left and right and correspond one-to-one with the lower truss bars.

[0097] The portion of the lower steel strand anchor 2 extending out of the concrete substrate 5 can be one or more of the following: straight, straight with end anchoring reinforcement 20, curved, curved with end anchoring reinforcement 20, and collar. In this embodiment, all are straight.

[0098] Anchoring reinforcements are designed to enhance the anchoring and gripping force of steel strands in concrete. They can be fixed to the ends of steel strands in various forms or can be anchors of a general type.

[0099] In other embodiments, it can also be a straight type with an anchoring reinforcement 20 at the end, such as... Figure 14 As shown; or it can be a curved shape, such as Figure 15 As shown; or a curved type with an anchoring reinforcement 20 at the end, such as Figure 16 As shown.

[0100] The lower steel strand anchor 2 is connected to the lower steel mesh by lap splicing, welding or sleeve connection, and the lower steel strand anchor 2 is close to the side of the lower truss bar 4.

[0101] The top reinforcement bar 3 of the truss is a steel bar.

[0102] See Example 2 Figure 2 and Figure 3 As shown.

[0103] Unlike Example 1, the truss top reinforcement 3 in Example 2 is a steel structural member.

[0104] See Figure 4 for Example 3.

[0105] Unlike Embodiment 1, the portion of the lower steel strand anchor 2 extending out of the concrete substrate 5 is a collar, which is a U-shaped steel strand. The two legs of the steel strand are respectively fixedly connected between two adjacent lower truss bars 4, and the opening of the collar faces inward.

[0106] The construction method for fall-prevention concrete floor slabs described in the above embodiments follows these steps:

[0107] Step 1: Prefabricate steel components in the factory.

[0108] Step 2: Erect the formwork for the floor slab.

[0109] Step 3: Lay the steel truss, lower steel strand anchors 2, and lower layer of transverse reinforcing bars.

[0110] Step 4: Pour concrete to form a concrete base plate 5.

[0111] Step 5: Cure the concrete to the predetermined strength.

[0112] Example 4 is shown in 5-6.

[0113] Unlike Embodiment 1, in Embodiment 4, the lower steel strand anchor 2 is a whole steel strand installed along the longitudinal length of the floor slab, and the steel strand is a prestressed steel strand.

[0114] The construction method for this type of fall-resistant concrete floor slab includes the following steps:

[0115] Step 1: Prefabricate steel components in the factory.

[0116] Step 2: Erect the formwork for the floor slab.

[0117] Step 3: Lay the steel truss, lower steel strand anchor 2, and lower transverse reinforcement; tension the lower steel strand anchor 2 and apply prestress.

[0118] Step 4: Pour concrete to form a concrete base plate 5.

[0119] Step 5: Cure the concrete to the predetermined strength. Cut the lower steel strand anchor 2.

[0120] See Example 5 Figure 7 As shown.

[0121] A fall-prevention concrete floor slab includes a precast section and a composite cast-in-place section. The composite cast-in-place section includes cast-in-place reinforcement bars and cast-in-place concrete 7. The cast-in-place reinforcement bars include upper transverse reinforcement bars 8 and upper steel strand anchors 9.

[0122] The upper transverse steel bars 8 are connected to the truss upper steel bars 3 to form an upper steel mesh. The cast-in-place concrete 7 is poured to the upper side of the concrete substrate 5 and covers the cast-in-place steel bars and the precast steel components. The exposed part of the concrete substrate 5 forms a concrete composite slab to prevent falling.

[0123] The upper steel strand anchor 9 is installed on both sides of the longitudinal direction of the cast-in-place concrete 7 and is connected to the upper steel mesh. The outer end of the upper steel strand anchor 9 extends out of the longitudinal direction of the cast-in-place concrete 7.

[0124] The upper steel strand anchor 9 consists of a section of steel strand installed at the end along the longitudinal direction of the floor slab. In other embodiments, a whole steel strand can be installed along the longitudinal direction of the floor slab, and the steel strand can be a prestressed steel strand.

[0125] The portion of the upper steel strand anchor 9 extending out of the concrete substrate 5 is a straight line as in Embodiment 1, but in other embodiments it can also be formed as a collar as in Embodiment 3.

[0126] The connection between the upper steel strand anchor 9 and the upper steel mesh is by lap splicing, welding or sleeve connection, and the upper steel strand anchor 9 is close to the side of the upper truss reinforcement 3.

[0127] The construction method for this type of fall-resistant concrete floor slab includes the following steps:

[0128] Step 1: Prefabricate steel components in the factory.

[0129] Step 2: Erect the formwork for the floor slab.

[0130] Step 3: Lay the steel truss, lower steel strand anchors 2, and lower layer of transverse reinforcing bars.

[0131] Step 4: Pour concrete to form a concrete base plate 5.

[0132] Step 5: Cure the concrete to the predetermined strength.

[0133] Step six: After the prefabricated parts are transported to the site, they are hoisted into place.

[0134] Step 7: Lay the upper layer of transverse reinforcing bars 8 and the upper steel strand anchors 9.

[0135] Step 8: Erect the formwork for the cast-in-place section.

[0136] Step 9: Construct cast-in-place concrete 7 to form a composite floor slab.

[0137] Step 10: Cure the concrete to the predetermined strength.

[0138] When the lower steel strand anchor 2 or the upper steel strand anchor 9 is a single steel strand running longitudinally along the floor slab, the following steps are required after step three: Tensioning the lower steel strand anchor 2 and applying prestress. After step five, the following steps are required: Cutting off the lower steel strand anchor 2. After step seven, the following steps are required: Tensioning the upper steel strand anchor 9 and applying prestress. After step nine, the following steps are required: Cutting off the upper steel strand anchor 9.

[0139] See Example 6 Figure 8-9 As shown.

[0140] A fall-prevention concrete floor slab includes a slab body comprising a lower precast slab, an upper precast slab, a central connecting rib 16, and a central hollow hole 17. The lower precast slab includes a lower slab reinforcing mesh and a lower slab concrete 10. The lower slab reinforcing mesh includes lower slab longitudinal bars 11 and lower slab transverse bars 12. The longitudinal ends of the lower slab reinforcing mesh are also fixedly connected with lower steel strand anchors 2. The lower slab concrete 10 covers the lower slab reinforcing mesh and the lower steel strand anchors 2, with both ends of the lower steel strand anchors 2 extending beyond the longitudinal ends of the lower slab concrete 10.

[0141] The upper precast slab includes an upper slab steel mesh and an upper slab concrete 13. The upper slab steel mesh includes upper slab longitudinal bars 14 and upper slab transverse bars 15. The longitudinal ends of the upper slab steel mesh are also fixedly connected with upper steel strand anchors 9. The upper slab concrete 13 covers the upper slab steel mesh and the upper steel strand anchors 9. The two ends of the upper steel strand anchors 9 extend out of the longitudinal ends of the upper slab concrete 13.

[0142] The central connecting rib 16 and the central hollow hole 17 are alternately arranged between the upper precast slab and the lower precast slab. The central connecting rib 16 is a rib arranged longitudinally at intervals, and the central connecting rib 16 connects the upper precast slab and the lower precast slab.

[0143] The upper steel strand anchor 9 is a section of steel strand installed at the end along the longitudinal direction of the floor slab, as shown in Embodiment 5. In other embodiments, a whole steel strand can be installed along the longitudinal direction of the floor slab, and the whole steel strand is a prestressed steel strand.

[0144] The portion of the upper steel strand anchor 9 extending out of the concrete substrate 5 forms a straight line as in Embodiment 5. In other embodiments, it can also form a collar as in Embodiment 3. The connection between the upper steel strand anchor 9 and the upper plate steel mesh is by lap splicing, welding, or sleeve connection. The upper steel strand anchor 9 is close to one side of the upper plate longitudinal reinforcement 14.

[0145] The lower steel strand anchor 2 is a section of steel strand installed at the end along the longitudinal direction of the floor slab, as shown in Embodiment 1. In other embodiments, it can also be a whole steel strand installed along the longitudinal direction of the floor slab, and the whole steel strand is a prestressed steel strand.

[0146] The portion of the lower steel strand anchor 2 extending out of the concrete substrate 5 forms a straight line as in Embodiment 1. In other embodiments, it can also form a collar as in Embodiment 3. The connection between the lower steel strand anchor 2 and the lower plate steel mesh is by lap splicing, welding, or sleeve connection. The lower steel strand anchor 2 is close to one side of the lower plate longitudinal reinforcement 11.

[0147] The construction method for this type of fall-resistant concrete floor slab includes the following steps:

[0148] Step 1: The factory manufactures the lower slab reinforcement mesh, lower steel strand anchors 2, upper slab reinforcement mesh, and upper steel strand anchors 9.

[0149] Step 2: Erect the formwork for the floor slab.

[0150] Step 3: Connect the lower plate steel mesh and lower steel strand anchor 2, as well as the upper plate steel mesh and upper steel strand anchor 9 into one piece. First, lay the lower plate steel mesh and lower steel strand anchor 2, then add the inner mold of the central hollow hole 17, and finally lay the upper plate steel mesh and upper steel strand anchor 9.

[0151] Step 4: Pour concrete to form the slab.

[0152] Step 5: Cure the concrete to the predetermined strength.

[0153] Step 6: Remove the inner mold or keep the inner mold.

[0154] When the lower steel strand anchor 2 or the upper steel strand anchor 9 is a single steel strand running longitudinally along the floor slab, the following steps are required after step three: tension the lower steel strand anchor 2 and apply prestress; tension the upper steel strand anchor 9 and apply prestress. After step five, the following steps are required: cut off the lower steel strand anchor 2 and cut off the upper steel strand anchor 9.

[0155] See Example 7 Figure 10-11 As shown, unlike Embodiment Six, the hollow hole 17 in the middle is filled with a filler 18, which is plastic, rubber, sponge or a combination thereof.

[0156] The upper steel strand anchor 9 is a section of steel strand set at the end along the longitudinal direction of the floor slab, as shown in Example 5.

[0157] The lower steel strand anchor 2 is a section of steel strand installed at the end along the longitudinal direction of the floor slab, as shown in Example 5.

[0158] The construction method for this type of fall-resistant concrete floor slab includes the following steps:

[0159] Step 1: The factory manufactures the lower slab reinforcement mesh, lower steel strand anchors 2, upper slab reinforcement mesh, and upper steel strand anchors 9.

[0160] Step 2: Erect the formwork for the floor slab.

[0161] Step 3: Connect the lower plate steel mesh and lower steel strand anchor 2, as well as the upper plate steel mesh and upper steel strand anchor 9 into one piece. First, lay the lower plate steel mesh and lower steel strand anchor 2, then add the inner mold with the central hollow hole 17, and fill the space between the inner molds with filler material 18. Finally, lay the upper plate steel mesh and upper steel strand anchor 9.

[0162] Step 4: Pour concrete to form the slab.

[0163] Step 5: Cure the concrete to the predetermined strength.

[0164] Step 6: Remove the inner mold or keep the inner mold.

[0165] See Example 8 Figure 12 As shown, unlike Example 7,

[0166] The upper steel strand anchor 9 is a section of steel strand set at the end along the longitudinal direction of the floor slab, as shown in Example 5.

[0167] The lower steel strand anchor 2 is a whole steel strand installed along the longitudinal length of the floor slab, and the whole steel strand is a steel strand with applied prestress.

[0168] The construction method for this type of fall-resistant concrete floor slab includes the following steps:

[0169] Step 1: The factory manufactures the lower slab reinforcement mesh, lower steel strand anchors 2, upper slab reinforcement mesh, and upper steel strand anchors 9.

[0170] Step 2: Erect the formwork for the floor slab.

[0171] Step 3: Connect the lower plate steel mesh and lower steel strand anchor 2, as well as the upper plate steel mesh and upper steel strand anchor 9, into a whole. First, lay the lower plate steel mesh and lower steel strand anchor 2, then add an inner mold with a hollow hole 17 in the middle, and fill the space between the inner molds with filler material 18. Finally, lay the upper plate steel mesh and upper steel strand anchor 9; tension the lower steel strand anchor 2 to apply prestress.

[0172] Step 4: Pour concrete to form the slab.

[0173] Step 5: Cure the concrete to the predetermined strength; cut off the lower steel strand anchor 2.

[0174] Step 6: Remove the inner mold or keep the inner mold.

[0175] In the above embodiments, the concrete slab can be provided with stiffening ribs or stiffening plates, the stiffening ribs have openings, and can also be provided with pre-embedded connectors.

[0176] See Figure 13 As shown, a connection node for a fall-prevention concrete floor slab includes a slab body and a vertical member 19 fixedly connected to the slab body. The portion of the lower steel strand anchor extending out of the slab body is anchored into the vertical member 19, and the portion of the upper steel strand anchor extending out of the slab body is also anchored into the vertical member 19. The vertical member 19 is a beam and / or a wall, and the extended steel strands are integrally formed with the concrete or grout in the node area.

Claims

1. A fall-prevention concrete floor slab, comprising a slab body, characterized in that: The slab includes a precast section, which includes a lower concrete base plate (5) and precast steel components. The precast steel components include a steel truss, lower transverse steel bars (1), and lower steel strand anchors (2). The steel truss includes longitudinal top truss bars (3), longitudinal bottom truss bars (4), and truss web bars connecting the two. The bottom truss bars (4) are located within the concrete substrate. The lower transverse steel bars are fixedly connected to the bottom truss bars (4) to form a lower steel mesh. The upper truss bar (3) is parallel to the lower truss bar (4). The upper truss bar (3) is located above the concrete base plate (5). The upper truss bar (3) and the lower truss bar (4) are connected by the truss web bar (6). The bottom of the truss web bar (6) is embedded in the concrete base plate (5), and the upper part of the truss web bar (6) extends out of the concrete base plate (5). The lower steel strand anchor (2) is installed on both sides of the concrete substrate (5) and connected to the lower steel mesh. The outer end of the lower steel strand anchor (2) extends beyond the longitudinal end of the concrete substrate (5) by a length not less than 3d. The lower steel strand anchor (2) is connected to the lower steel mesh by lap splicing, welding or sleeve connection, and the lower steel strand anchor (2) is close to one side of the lower truss reinforcement (4). The truss top reinforcement (3) is a steel bar or a steel section component. It also includes a vertical member (19) fixedly connected to the plate. The portion of the lower steel strand anchor extending out of the plate is anchored into the vertical member (19). The vertical member (19) is a beam and / or a wall. The extended steel strands are integrated with the concrete or grout in the joint area. The lower horizontal reinforcement (1) does not extend out of the slab.

2. The anti-fall concrete floor slab according to claim 1, characterized in that: The lower steel strand anchor (2) is a section of steel strand set at the end along the longitudinal direction of the floor slab, or the lower steel strand anchor (2) is a whole steel strand set along the longitudinal direction of the floor slab. The steel strand is a prestressed steel strand. The portion of the lower steel strand anchor (2) extending out of the concrete substrate (5) can be one or more of the following: straight type, straight type with end anchor reinforcement (20), curved type, curved type with end anchor reinforcement (20), and collar.

3. The anti-fall concrete floor slab according to claim 1 or 2, characterized in that: The slab also includes a composite cast-in-place section, which includes cast-in-place reinforcement and cast-in-place concrete (7). The cast-in-place reinforcement includes upper transverse reinforcement (8) and upper steel strand anchors (9). The upper transverse steel bars (8) are connected to the truss top bars (3) to form an upper steel mesh. The cast-in-place concrete (7) is poured to the upper side of the concrete base plate (5) and covers the portion of the cast-in-place steel bars and precast steel components exposed on the upper side of the concrete base plate (5) to form a fall-prevention concrete composite slab. The upper steel strand anchor (9) is set inside the longitudinal sides of the cast-in-place concrete (7) and connected to the upper steel mesh. The outer end of the upper steel strand anchor (9) extends out of the longitudinal end of the cast-in-place concrete (7). The connection between the upper steel strand anchor (9) and the upper steel mesh is by lap, welding or sleeve connection. The upper steel strand anchor (9) is close to the side of the upper truss reinforcement (3).

4. The anti-fall concrete floor slab according to claim 3, characterized in that: The upper steel strand anchor (9) is a section of steel strand set at the end along the longitudinal direction of the floor slab, or the upper steel strand anchor (9) is a whole steel strand set along the longitudinal direction of the floor slab. The steel strand is a prestressed steel strand. The portion of the upper steel strand anchor (9) extending out of the concrete substrate (5) can be one or more of the following: straight type, straight type with end anchor reinforcement (20), curved type, curved type with end anchor reinforcement (20), and collar.

5. A fall-prevention concrete floor slab, comprising a slab body, characterized in that: The slab includes a lower precast slab, an upper precast slab, a middle connecting rib (16), and a middle hollow hole (17). The lower precast slab includes a lower slab steel mesh and lower slab concrete (10). The lower slab steel mesh includes lower slab longitudinal bars (11) and lower slab transverse bars (12). The longitudinal ends of the lower slab steel mesh are also fixedly connected with lower steel strand anchors (2). The lower slab concrete (10) covers the lower slab steel mesh and the lower steel strand anchors (2). The two ends of the lower steel strand anchors (2) extend out of the longitudinal ends of the lower slab concrete (10). The upper precast slab includes an upper slab steel mesh and upper slab concrete (13). The upper slab steel mesh includes upper slab longitudinal bars (14) and upper slab transverse bars (15). The longitudinal ends of the upper slab steel mesh are also fixedly connected with upper steel strand anchors (9). The upper slab concrete (13) covers the upper slab steel mesh and the upper steel strand anchors (9). The two ends of the upper steel strand anchors (9) extend out of the longitudinal ends of the upper slab concrete (13). The central connecting rib (16) and the central hollow hole (17) are alternately arranged between the upper precast slab and the lower precast slab. The central connecting rib (16) is a rib arranged longitudinally at intervals, and the central connecting rib (16) connects the upper precast slab and the lower precast slab. It also includes a vertical member (19) fixedly connected to the plate. The portion of the lower steel strand anchor extending out of the plate is anchored into the vertical member (19). The vertical member (19) is a beam and / or a wall. The extended steel strands are integrated with the concrete or grout in the joint area. Neither the lower horizontal reinforcement (12) nor the upper horizontal reinforcement (15) extends beyond the plate.

6. The anti-fall concrete floor slab according to claim 5, characterized in that: The central hollow hole (17) is filled with a filler (18), which is plastic, rubber, sponge or a combination thereof.

7. The anti-fall concrete floor slab according to claim 5, characterized in that: The upper steel strand anchor (9) is a section of steel strand set at the end along the longitudinal direction of the floor slab or a whole steel strand set along the longitudinal direction of the floor slab. The whole steel strand is a prestressed steel strand. The part of the upper steel strand anchor (9) extending out of the concrete substrate (5) is straight and / or forms a collar. The connection between the upper steel strand anchor (9) and the upper slab reinforcement mesh is lapped, welded or sleeved. The upper steel strand anchor (9) is close to the side of the upper slab longitudinal reinforcement (14). The lower steel strand anchor (2) is a section of steel strand set at the end along the longitudinal direction of the floor slab or a whole steel strand set along the longitudinal direction of the floor slab. The whole steel strand is a prestressed steel strand. The part of the lower steel strand anchor (2) extending out of the concrete substrate (5) is one or more of the following: straight type, straight type with anchor reinforcement (20) at the end, curved type, curved type with anchor reinforcement (20) at the end, and collar type. The connection between the lower steel strand anchor (2) and the lower slab reinforcement mesh is lapped, welded, or sleeved. The lower steel strand anchor (2) is close to the side of the lower slab longitudinal reinforcement (11).

8. A construction method for a fall-resistant concrete floor slab according to claim 1 or 2, characterized in that, The construction steps are as follows: Step 1: Prefabricate the steel components in the factory; Step 2: Erect the formwork for the floor slab; Step 3: Lay the steel truss, lower steel strand anchors (2), and lower transverse reinforcement; Step 4: Pour concrete to form a concrete base plate (5). Step 5: Cure the concrete to the predetermined strength.

9. The construction method for fall-prevention concrete floor slabs according to claim 8, characterized in that: After step three, add: tensioning the steel strand anchor (2) and applying prestress; Add the following step after step five: cut off the lower steel strand anchor (2).

10. A construction method for a fall-resistant concrete floor slab according to claim 3 or 4, characterized in that, The construction steps are as follows: Step 1: Prefabricate the steel components in the factory; Step 2: Erect the formwork for the floor slab; Step 3: Lay the steel truss, lower steel strand anchors (2), and lower transverse reinforcement; Step 4: Pour concrete to form a concrete base plate (5). Step 5: Cure the concrete to the predetermined strength; Step six: After the prefabricated components are transported to the site, they are hoisted into place; Step 7: Lay the upper transverse steel bars (8) and the upper steel strand anchors (9). Step 8: Erect the formwork for the cast-in-place section; Step 9: Construct cast-in-place concrete (7) to form composite floor slabs; Step 10: Cure the concrete to the predetermined strength.

11. The construction method for fall-resistant concrete floor slabs according to claim 10, characterized in that: After step three, add: tensioning the steel strand anchor (2) and applying prestress; Add the following step after step five: cut off the lower steel strand anchor (2); After step seven, add: tensioning the steel strand anchor (9) and applying prestress; Add the following step after step nine: cut off the upper steel strand anchor (9).

12. A construction method for a fall-prevention concrete floor slab according to any one of claims 5-7, characterized in that, The construction steps are as follows: Step 1: The factory manufactures the lower plate steel mesh, lower steel strand anchors (2), upper plate steel mesh and upper steel strand anchors (9). Step 2: Erect the formwork for the floor slab; Step 3: Connect the lower plate steel mesh and lower steel strand anchor (2) and the upper plate steel mesh and upper steel strand anchor (9) into one piece. First, lay the lower plate steel mesh and lower steel strand anchor (2), then add the inner mold of the central hollow hole (17), and finally lay the upper plate steel mesh and upper steel strand anchor (9). Step 4: Pour concrete to form the slab; Step 5: Cure the concrete to the predetermined strength; Step 6: Remove the inner mold or keep the inner mold.

13. The construction method for fall-resistant concrete floor slabs according to claim 12, characterized in that: After step three, add: tensioning the lower steel strand anchor (2) and applying prestress; tensioning the upper steel strand anchor (9) and applying prestress; After step five, add: cut off the lower steel strand anchor (2), cut off the upper steel strand anchor (9).

Images