Construction method for pre-embedded anchor bolt positioning mark installation and hanger installation in cast-in-place floor slabs

Abstract

This invention discloses a construction method for installing hangers with pre-embedded anchor bolt positioning marks in cast-in-place floor slabs, belonging to the field of building construction technology. It aims to solve the problem of easily damaging pre-embedded pipelines within the floor slab when drilling holes for anchoring various hangers under cast-in-place floor slabs. The invention includes the following steps: S1, detailed design to determine anchoring point locations; S2, fabrication of anchor bolt positioning labels; S3, layout and placement of anchor bolt positioning labels; S4, installation of concealed conduits; S5, drilling of anchoring points; S6, installation and anchoring of hangers. This invention uses self-adhesive anchor bolt positioning labels of different colors to pre-mark anchoring points. Concealed pipelines within the slab are avoided during installation. During hanger installation, holes are directly drilled at the marked locations on the anchor bolt positioning labels to fix the anchor bolts. This reduces the measurement and layout steps for hanger installation, avoids damage to concealed pipelines within the floor slab during drilling, effectively reduces rework and repairs, and shortens the hanger installation cycle.

Description

Technical Field

[0001] This invention belongs to the field of building construction technology, specifically relating to the construction method of installing hanging brackets for pre-embedded anchor bolt positioning marks in cast-in-place floor slabs. Background Technology

[0002] Reinforced concrete cast-in-place floor slabs are widely used in various industrial and civil buildings. Currently, the conduits for horizontally laid building electrical power, electrical lighting, integrated wiring, television and telephone, public address, and automatic fire alarm systems are usually designed to be concealed within the cast-in-place floor slab. This design offers advantages such as simple construction, straightforward forming, and high safety and reliability. The general construction process for cast-in-place floor slabs is as follows: layout and formwork erection → bottom reinforcement installation and binding → pre-embedded pipeline positioning and installation → top reinforcement installation and binding → concrete pouring → concrete curing → formwork removal.

[0003] Because there are generally many pipes concealed in cast-in-place floor slabs, and they cannot be visually detected after the floor slab is cast, the drilling process during the later installation of various hangers and anchors under the floor slab can easily damage the various conduits and the wires running through them.

[0004] Existing technology discloses a device and method for marking embedded pipelines in concrete slabs to avoid drilling damage, as per authorization announcement number CN 112932058 B. The device includes a main shell with an internal paint storage chamber. A partition with a discharge hole is located at the bottom of the paint storage chamber. A vertical rod is positioned along the vertical center line of the main shell, and a valve block for sealing the discharge hole is fixed at the bottom of the vertical rod. The method involves first drawing paint marking lines on a template corresponding to the locations of the embedded pipelines. Then, concrete is poured, and after demolding, the paint marking lines on the template are imprinted on the concrete base slab. The direction of the paint marking lines indicates the direction of the embedded pipelines in the concrete. The marking device provided by this invention can draw paint marking lines with good uniformity, and the width of the paint marking lines is adjustable. The method provides that the paint marking lines indicate the location of the embedded electrical conduits, allowing drilling to avoid the electrical conduits and prevent damage, thus protecting the conduits.

[0005] Article 42 of the Environmental Protection Law stipulates that enterprises, institutions, and other producers and operators that discharge pollutants shall take measures to prevent and control pollution and harm to the environment caused by waste gas, wastewater, waste residue, medical waste, dust, malodorous gases, radioactive substances, noise, vibration, light radiation, and electromagnetic radiation generated in production, construction, or other activities. Article 45 of the Air Pollution Prevention and Control Law stipulates that production and service activities that generate waste gas containing volatile organic compounds shall be carried out in enclosed spaces or equipment, and pollution prevention and control facilities shall be installed and used in accordance with regulations; if enclosed spaces are not possible, measures shall be taken to reduce waste gas emissions. Based on the aforementioned legal provisions, since paint contains volatile organic compounds, paint spraying or brushing operations in open spaces at construction sites are currently prohibited by environmental protection departments, greatly reducing the practicality of the aforementioned invention. Summary of the Invention

[0006] 1. Technical problems to be solved

[0007] To address the shortcomings of existing technologies, this invention aims to provide a construction method for installing anchor bolt positioning marks and hangers in cast-in-place floor slabs, achieving lower costs and better results while avoiding damage to concealed pipelines within the floor slab caused by subsequent drilling and anchoring of various hangers under the cast-in-place floor slab.

[0008] 2. Technical Solution

[0009] The construction method for installing anchor bolt positioning marks and hangers in cast-in-place floor slabs includes the following steps:

[0010] S1. Detailed design to determine anchorage locations

[0011] In this step, based on the original design drawings, a comprehensive and detailed design of various professional equipment and pipelines is carried out to determine the structure of the hangers, draw the hanger fabrication and processing drawings and the installation plan layout drawings, and on this basis, draw the anchor point plan layout drawings and count the number of anchor bolts of various diameters; prioritize the use of combined hanger systems to reduce the number of anchor points by reducing the number of hangers.

[0012] S2. Make anchor bolt positioning tags

[0013] In this step, self-adhesive anchor bolt positioning labels are customized based on the number of anchor bolts counted in step S1; the anchor bolt positioning labels are printed on a full sheet of A4 size removable (weakly adhesive) self-adhesive paper; the anchor bolt positioning labels are circular, with the inner and outer circles concentric, the outer circle diameter is 25mm, and the inner circle diameter is 8mm; anchor bolt positioning labels for different systems are made in different colors.

[0014] S3. Lay out and position the anchor bolts, then affix the anchor bolt positioning labels.

[0015] In this step, the anchor bolt positioning label is laid out and positioned according to the anchor point layout plan described in step S1 after the bottom formwork of the cast-in-place floor slab is erected. A cross line is marked on the bottom formwork with a marker or ink line, and the intersection of the cross lines is the anchor point. When pasting the anchor bolt positioning label, peel it off from the backing paper of the self-adhesive paper, align the center of its ring with the anchor point, and press it flat and tight.

[0016] S4. Concealed wiring installation

[0017] In this step, the concealed conduit should be laid after the bottom reinforcement of the cast-in-place floor slab is laid and preferably before the top reinforcement is laid, according to the design drawings. If its horizontal position conflicts with the horizontal position of the anchor bolt positioning label, it should be avoided and tied firmly according to the specifications.

[0018] S5, Anchor point drilling

[0019] In this step, the anchoring point drilling is carried out after the bottom formwork of the cast-in-place floor slab is removed and cleaned. The anchor bolt positioning label will be exposed after the bottom formwork is removed. When drilling, refer to the plan layout of the anchoring point of the hanger described in step S1 to find the corresponding anchor bolt positioning label and drill vertically upwards with its center. The drilling depth of the anchor hole is the effective depth of the anchor bolt inserted into the floor slab in the anchored state plus 5mm to 10mm, which is controlled by a depth gauge. The drilling is carried out by an impact electric drill with a drill bit that matches the diameter of the anchor bolt and the drilling depth of the anchor hole.

[0020] S6. Hanger installation and anchoring

[0021] In this step, the hanger is fabricated in advance according to the hanger fabrication and processing drawing described in step S1, and then anchored in the corresponding holes drilled in step S5 according to the hanger installation plan layout drawing described in step S1.

[0022] 3. Beneficial effects

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The present invention uses anchor bolt positioning tags to pre-embed and mark the drilling positions of anchor bolts for later installation of under-slab hangers on the bottom formwork of cast-in-place floor slabs. Various conduits concealed in the slab can be actively avoided during installation. After the bottom formwork is removed, the anchor bolt positioning tags are attached to the bottom surface of the floor slab. When drilling in the later stage, drilling at the location of the anchor bolt positioning tags can naturally avoid the concealed pipelines in the floor slab, avoid damage to them, and reduce rework and repair costs.

[0025] (2) In the construction stage of cast-in-place floor slab, the anchoring position of the under-slab hanger is pre-embedded and marked. The measurement on the formwork is simpler and more efficient than the measurement under the floor slab. The positioning measurement and layout process during the later installation of the hanger is simplified or even eliminated, which shortens the installation time of the hanger and facilitates the overall progress coordination and control.

[0026] (3) Compared with the concrete floor slab pre-embedded pipeline marking device and method that can avoid drilling damage in the authorization announcement number CN 112932058 B, the paint painting device used in the invention has a relatively complex structure and paints the entire line of the concealed conduit at the construction site. The present invention uses removable (weak adhesive) self-adhesive paper to customize anchor bolt positioning labels for pre-embedded marking. The anchor bolt positioning labels are inexpensive to produce, have self-adhesive properties and are easy to operate. At the same time, it avoids the pollution caused by paint painting operations to the environment, and has significantly lower implementation costs and stronger practicality.

[0027] (4) Compared with the concrete floor slab embedded pipeline marking device and method that can avoid drilling damage, which is authorized by announcement number CN 112932058 B, the entire line of the concealed conduit is painted with paint markings, which will result in a large number of paint markings being exposed at the bottom of the floor slab; the anchor bolt positioning label of the present invention has a small area and can be covered by the base of the hanger after the hanger is installed, resulting in a significantly better overall appearance quality. Detailed Implementation

[0028] The present invention will be further described in detail below with reference to the embodiments.

[0029] Example

[0030] The construction method for installing anchor bolt positioning marks and hangers in cast-in-place floor slabs includes the following steps:

[0031] S1. Detailed design to determine anchorage locations

[0032] In this step, based on the original design drawings, a comprehensive and detailed design of various professional equipment and pipelines is carried out to determine the hanger structure form, draw hanger fabrication and processing drawings and hanger installation plan layout drawings, and on this basis, draw anchor point plan layout drawings and count the number of anchor bolts of various diameters; prioritize the use of combined hanger systems to reduce the number of anchor points by reducing the number of hangers.

[0033] S2. Make anchor bolt positioning tags

[0034] In this step, self-adhesive anchor bolt positioning labels are customized based on the number of anchor bolts counted in step S1; the anchor bolt positioning labels are printed on a full sheet of A4 size removable (weakly adhesive) self-adhesive paper; the anchor bolt positioning labels are circular, with the inner and outer circles concentric, the outer circle diameter is 25mm, and the inner circle diameter is 8mm; anchor bolt positioning labels for different systems are made in different colors.

[0035] Preferably, the anchor bolt positioning labels for water supply and drainage pipeline system hangers are made of red paper, the anchor bolt positioning labels for power and low voltage cable tray system hangers are made of yellow paper, and the anchor bolt positioning labels for air duct system hangers are made of blue paper; two white straight lines that are perpendicular to each other and intersect at the center of the ring are printed on the anchor bolt positioning labels as auxiliary alignment marks.

[0036] The anchor bolt positioning label needs to be affixed to the bottom formwork of the cast-in-place floor slab. Its removable (weakly adhesive) design ensures that it can automatically peel off the formwork and remain attached to the bottom of the floor slab when the formwork is removed later. The anchor bolt positioning label is circular, serving as both an observation hole for placement and a target for drilling, while also enhancing the adhesion between the label and the concrete. Different colors are used for the anchor bolt positioning labels of different systems to facilitate easy differentiation during drilling and anchoring of the hangers, enabling rapid positioning and selection.

[0037] S3. Lay out and position the anchor bolts, then affix the anchor bolt positioning labels.

[0038] In this step, the anchor bolt positioning label is laid out and positioned according to the anchor point layout plan after the bottom formwork of the cast-in-place floor slab is erected. A cross line is marked with a marker or ink line, and the intersection of the cross lines is the anchor point. When pasting the anchor bolt positioning label, peel it off from the backing paper, align the center of its ring with the anchor point, and press it flat and tight.

[0039] Preferably, after the anchor bolt positioning label is pasted, the horizontal deviation between its center and the anchor point is no more than 2mm.

[0040] S4. Concealed wiring installation

[0041] In this step, the concealed conduit should be laid after the bottom reinforcement of the cast-in-place floor slab is laid and preferably before the top reinforcement is laid, according to the design drawings. If its horizontal position conflicts with the horizontal position of the anchor bolt positioning label, it should be avoided and tied firmly according to the specifications.

[0042] Preferably, the horizontal distance between the concealed conduit in the cast-in-place floor slab and the anchor bolt positioning label is not less than 30mm.

[0043] S5, Anchor point drilling

[0044] In this step, the anchoring point drilling is carried out after the bottom formwork of the cast-in-place floor slab is removed and cleaned. The anchor bolt positioning label will be exposed after the bottom formwork is removed. When drilling, refer to the plan layout of the anchoring point of the hanger described in step S1 to find the corresponding anchor bolt positioning label and drill vertically upwards with its center. The drilling depth of the anchor hole is the effective depth of the anchor bolt inserted into the floor slab in the anchored state plus 5mm to 10mm, which is controlled by a depth gauge. The drilling is carried out by an impact electric drill with a drill bit that matches the diameter of the anchor bolt and the drilling depth of the anchor hole.

[0045] S6. Hanger installation and anchoring

[0046] In this step, the hanger is fabricated in advance according to the hanger fabrication and processing drawing described in step S1, and then anchored in the corresponding holes drilled in step S5 according to the hanger installation plan layout drawing described in step S1.

[0047] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. Construction method for installing hangers with pre-embedded anchor bolt positioning marks in cast-in-place floor slabs, characterized by: Includes the following steps: S1. Detailed design to determine anchorage locations In this step, the comprehensive layout and detailed design of various professional equipment and pipelines are carried out based on the original design drawings. The structural form of the hanger is determined, and the hanger fabrication and installation plan layout are drawn. On this basis, the anchor point layout plan is drawn, and the number of anchor bolts of various diameters is counted. A combined hanger system is adopted to reduce the number of anchor points by reducing the number of hangers. S2. Make anchor bolt positioning tags In this step, self-adhesive anchor bolt positioning labels are customized based on the number of anchor bolts counted in step S1. The anchor bolt positioning labels are printed on a full sheet of A4 removable weak adhesive paper. The anchor bolt positioning labels are circular with concentric inner and outer circles, with an outer circle diameter of 25mm and an inner circle diameter of 8mm. Different colors are used for anchor bolt positioning labels for different systems. S3. Lay out and position the anchor bolts, then affix the anchor bolt positioning labels. In this step, the anchor bolt positioning label is laid out and positioned according to the anchor point layout plan described in step S1 after the bottom formwork of the cast-in-place floor slab is erected. A cross line is marked on the bottom formwork with a marker or ink line, and the intersection of the cross lines is the anchor point. When pasting the anchor bolt positioning label, peel it off from the backing paper of the self-adhesive paper, align the center of its ring with the anchor point, and press it flat. S4. Concealed wiring installation In this step, the concealed conduit should be laid after the bottom reinforcement of the cast-in-place floor slab is laid and preferably before the top reinforcement is laid, according to the design drawings. If its horizontal position conflicts with the horizontal position of the anchor bolt positioning label, it should be avoided and tied firmly according to the specifications. S5, Anchor point drilling In this step, the anchoring point drilling is carried out after the bottom formwork of the cast-in-place floor slab is removed and cleaned. The anchor bolt positioning label will be exposed after the bottom formwork is removed. When drilling, refer to the plan layout of the anchoring point of the hanger described in step S1 to find the corresponding anchor bolt positioning label and drill vertically upwards with its center. The drilling depth of the anchor hole is the effective depth of the anchor bolt inserted into the floor slab in the anchored state plus 5mm to 10mm, which is controlled by a depth gauge. The drilling is carried out by an impact electric drill with a drill bit that matches the diameter of the anchor bolt and the drilling depth of the anchor hole. S6. Hanger installation and anchoring In this step, the hanger is fabricated in advance according to the hanger fabrication and processing drawing described in step S1, and then anchored in the corresponding holes drilled in step S5 according to the hanger installation plan layout drawing described in step S1.