A kind of steel bar protective layer quick measurement device and method before construction

Abstract

The present invention discloses a device and method for rapid pre-construction measurement of a steel bar protective layer, comprising a main measuring ruler, an anchor device of a front fulcrum device and an anchor plate of the front fulcrum device, the main measuring ruler sleeve is provided with a front fulcrum device and a rear fulcrum device, the front fulcrum device is composed of an anchor device of the front fulcrum device, an anchor plate of the front fulcrum device, a sleeve box of the front fulcrum device and a slot of the front fulcrum device, the front fulcrum device is composed of an anchor device of the rear fulcrum device, an anchor plate of the rear fulcrum device, a sleeve box of the rear fulcrum device and a slot of the rear fulcrum device. The device and method for rapid pre-construction measurement of a steel bar protective layer can realize rapid pre-construction measurement of a steel bar protective layer, has a reasonable structure, a clear force transmission path, and safe and reliable force, which can effectively solve the problem of cumbersomeness of traditional measurement of steel bar protective layer using a ruler, and can avoid the problems of low accuracy, time-consuming operation and labor-consuming in traditional measurement of steel bar protective layer using a ruler.

Description

Technical Field

[0001] The invention relates to the technical field of concrete construction protective layer measurement, and in particular to a pre-construction rapid measurement device and method for a steel bar protective layer. Background Art

[0002] Concrete cover refers to the part of concrete in reinforced concrete components that protects the steel bars from direct exposure. It is the minimum distance from the concrete surface to the outer edge of the outermost steel bar nominal diameter. For post-tensioned prestressed bars, it is the distance from the outer edge of the casing or hole to the concrete surface. The minimum thickness of the cover is stipulated to ensure that the concrete structural components meet the durability requirements and the requirements for effective anchoring of the stressed steel bars.

[0003] Reinforced concrete structure is a widely used structural form in bridge engineering, house construction, and municipal engineering. In our daily work of construction project quality supervision, the inspection and supervision of the quality of reinforced concrete structure engineering is undoubtedly a key point. Due to the large volume and wide range of reinforced concrete projects, we often find that some construction units do not strictly control the thickness of the steel bar protective layer in the concrete structure during the construction process, resulting in inaccurate steel bar position. In addition, factors such as large deviations in template size cause the steel bar protective layer to exceed the standard, and after the concrete is poured, its internal structure cannot be intuitively seen, which brings hidden dangers to the project quality.

[0004] In addition to the quality of raw materials, the deviation of the steel bar protective layer of reinforced concrete structural components directly affects the mechanical properties and durability of reinforced concrete components, and is related to the safety and service life of the building. Therefore, all parties involved in construction should pay enough attention to the protective layer of reinforced concrete structures.

[0005] 1. From a mechanical point of view, reinforced concrete structural components are composed of steel bars and concrete. In terms of the mechanical properties of raw materials, steel bars have strong tensile strength; concrete has high compressive strength, but its tensile strength is very low. This combination plays their respective advantages and jointly bears the external loads borne by the structural components. Therefore, when we consider the stress conditions of reinforced concrete, we generally focus on the compressive stress of concrete and the tensile stress of steel bars. Whether the actual tensile stress of steel bars in reinforced concrete structural components can match the design calculated stress depends mainly on whether the position of the steel bars in the structure is correct. This is also the main reason why we require the thickness of the steel bar protective layer to be controlled. Generally speaking, whether it is a beam or a slab, the tensile steel bars should always be as close as possible to the edge of the concrete member on the tensile side. For example, the force reinforcement of the cantilever beam should be located in the upper tensile zone of the member. If the thickness of the steel bar protective layer is too large, the tensile stress of the concrete will exceed the standard and cracks will occur due to the inability of the steel bars to effectively play their due tensile role. In severe cases, the tensile stress of the steel bars will exceed the standard and the structure will break due to the decrease in the moment height of the tensile force on the steel bars in the upper part of the cantilever structure. Such accidents are not uncommon in the history of construction. For example, in large-scale cast-in-place floor slabs, if the lower row of steel bars is padded too high and the protective layer is too large, the tensile stress in the lower part of the concrete will exceed the standard under the action of external loads, which will also cause cracks in the bottom of the slab.

[0006] 2. From the analysis of the bonding strength between steel bars and concrete, the reason why steel bars and concrete can work together is that after the concrete hardens and reaches a certain strength, sufficient bonding strength is established between the two. This interaction force is called bond strength. The protective layer of the steel bars in the concrete must have a certain thickness to ensure the bond strength between the concrete and the steel bars. If the thickness of the steel bar protective layer is too small, the steel bars are too close to the edge of the structural member, which may easily cause the steel bars to be exposed or the surface concrete to peel off when the steel bars are stressed, which directly leads to a decrease in bond strength. In addition, if the steel bar protective layer is too small, the surface concrete will gradually carbonize over time, the edge steel bars will lose their protective function and cause the steel bars to rust, and the bond strength between the steel bars and the concrete will also be lost, thereby reducing the bearing capacity of the member, and in severe cases, it will also lead to the destruction of the entire structural system.

[0007] 3. From the durability analysis of the components, the role of the protective layer, as the name implies, is to protect the steel bars from rusting, in addition to the above, to ensure the durability of the reinforced concrete structure. There are many factors that affect the durability of reinforced concrete structures. In addition to special external factors, under normal use conditions, the main consideration is the atmospheric erosion that causes the steel bars to oxidize and rust. The factors such as the looseness of the concrete, cracks, and the small protective layer of the steel bars, coupled with the carbonization of the concrete and the electrochemical reaction of the steel bars, will accelerate this erosion process. The oxidation and rust of the steel bars will lead to volume expansion, resulting in the cracking of the concrete protective layer, causing a vicious cycle, further accelerating the corrosion process of the steel bars, and thus greatly shortening the service life of the building. Therefore, ensuring that the thickness of the protective layer is within the range specified by the design and specifications can protect the steel bars from rust to the greatest extent, delay the time for the depth of concrete carbonization to reach the surface of the steel bars, and ensure the service life of the structure. For buildings in some special environments, such as building structures in a corrosive gas environment, some special provisions should be made for the steel bar protective layer of the concrete structure in the design to ensure the durability of the building structure.

[0008] 4. From the analysis of the fire protection requirements of concrete, the protective layer also has a certain fire protection function for the steel bars inside the concrete. When a fire occurs in a building structure, the ambient temperature rises sharply, and the thermal expansion coefficients of the steel bars and concrete are different. When the expansion value of the steel bars gradually exceeds the expansion value of the concrete, the bond between the concrete and the steel bars will be damaged and destroyed; in addition, when the temperature of the steel bars rises to 700°C, the yield strength of the steel bars will be greatly reduced, and the conditions for working with the concrete will be lost, resulting in structural damage. However, concrete is a poor conductor of heat. It can protect the steel bars from being immediately affected by high temperatures, thereby delaying the time for the structure to lose its bearing capacity and buying time for fire rescue. For some special buildings or structures, in order to improve their fire resistance level, the design also has specific requirements for increasing the thickness of the concrete protective layer for some structural components.

[0009] The purpose of the present invention is to solve the current technical difficulties in the rapid pre-construction measurement of steel bar protection layers in China, and to provide a device and method for the rapid pre-construction measurement of steel bar protection layers with a more reasonable structure, more reliable force and simpler operation, so as to meet the urgent need for rapid pre-construction measurement of steel bar protection layers in China. Summary of the invention

[0010] The purpose of the present invention is to provide a device and method for rapid pre-construction measurement of a steel bar protective layer, so as to solve the problems of poor fire resistance, inability to prevent the spread of fire, and poor low temperature resistance mentioned in the above background technology.

[0011] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a pre-construction rapid measurement device for a steel bar protective layer, comprising a main measuring ruler, an anchor device of a front fulcrum device and an anchor plate of the front fulcrum device, the main measuring ruler is provided with a front fulcrum device and a rear fulcrum device, the front fulcrum device is composed of an anchor device of the front fulcrum device, an anchor plate of the front fulcrum device, a sleeve box of the front fulcrum device and a slot of the front fulcrum device, the front fulcrum device is composed of an anchor device of the rear fulcrum device, an anchor plate of the rear fulcrum device, a sleeve box of the rear fulcrum device and a slot of the rear fulcrum device, the left side of the main measuring ruler is provided with a sleeve box of the front fulcrum device, and the front fulcrum device is provided with a sleeve box of the front fulcrum device, and the front fulcrum device is provided with a sleeve box of the front fulcrum device. An anchor plate of a front fulcrum device is arranged at the upper end of the casing, and the anchor plate of the front fulcrum device is threadedly connected with the anchor device of the front fulcrum device, and the bottom end of the anchor device of the front fulcrum device is attached to the upper end of the main body measuring ruler, and a clamping groove of the front fulcrum device is arranged at the bottom end of the casing of the front fulcrum device, a casing of a rear fulcrum device is arranged at the right side of the main body measuring ruler, and an anchor plate of the rear fulcrum device is arranged at the upper end of the casing of the rear fulcrum device, the anchor plate of the rear fulcrum device is threadedly connected with the anchor device of the rear fulcrum device, and the bottom end of the anchor device of the rear fulcrum device is attached to the upper end of the main body measuring ruler, and a clamping groove of the rear fulcrum device is arranged at the bottom end of the casing of the rear fulcrum device.

[0012] A method for rapid pre-construction measurement of a steel bar protective layer comprises the following specific steps:

[0013] Step 1: The rear fulcrum device and the front fulcrum device are successively installed into the main measuring ruler through the sleeve box, and anchored through the anchor device;

[0014] Step 2: Adjust and fix the front support device according to the size of the steel bar protective layer;

[0015] Step 3: According to the requirements of the positive and negative difference of the steel bar protective layer plus the steel bar size, adjust the rear fulcrum device and fix it;

[0016] Step 4: Check whether the steel bar can be slotted between the rear support device and the front support device on the main measuring ruler;

[0017] Step 5: Adjust the steel bar protection layer according to the measurement results.

[0018] Preferably, a scale is provided on the left side of the front end of the main measuring ruler, and the scale is a standard scale.

[0019] Preferably, a circular hole is opened on the right side of the front end of the main measuring ruler, and the inner wall of the circular hole is smooth.

[0020] Preferably, the front fulcrum device and the rear fulcrum device are arranged in parallel, and the front fulcrum device is placed on the left of the rear fulcrum device.

[0021] Preferably, the anchor device of the front fulcrum device and the anchor device of the rear fulcrum device are both provided with external threads, and the anchor plates of the front fulcrum device and the anchor plates of the rear fulcrum device are internally provided with internal threads corresponding to the external threads.

[0022] Preferably, the clamping slot of the front fulcrum device and the clamping slot of the rear fulcrum device are both arranged in the form of hexagonal prisms.

[0023] Preferably, the measuring step needs to be based on the steel bar protection layer size and positive and negative difference requirements, and the steel bar size is also required.

[0024] Preferably, the measuring step is not limited by changes in the steel bar protective layer and is not limited by the form of the structure.

[0025] Preferably, the measuring step is applicable to the measurement of any concrete construction protective layer of bridge engineering and any concrete construction protective layer of building construction and municipal engineering.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The present invention can realize the rapid measurement of the steel bar protective layer before construction, has a reasonable structure, a clear force transmission path, and safe and reliable force bearing.

[0028] 2. Through the application of the present invention, it can effectively solve the cumbersome problem of using a ruler to measure the protective layer of steel bars in the traditional way, and can also avoid the problems of low precision, time-consuming and labor-consuming operation in the traditional way of measuring the protective layer of steel bars using a ruler, which greatly shortens the operation time, saves labor costs, and improves construction efficiency. In addition, because there is no need to adjust the ruler every time measuring, the safety risks in the process of measuring the protective layer of steel bars are effectively reduced.

[0029] 3. The structure of the present invention can adapt to the measurement of steel bar protection of any size, and there is no need to adjust during the measurement construction process of different steel bar protection layers, which simplifies the construction operation.

[0030] 4. The applicability of the present invention is extremely wide. It is not only applicable to the pre-construction measurement of the steel bar protective layer, but also, under the condition of having an adjustable positioning device, the technical scope of the present invention can be expanded to the measurement of any concrete construction protective layer of bridge engineering, and any concrete construction protective layer of building construction and municipal engineering.

[0031] 5. The present invention can also be applied to the measurement of any steel bar protective layer, and there is no need to use a traditional ruler for measurement, which has significant economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic front view of the structure of the present invention;

[0033] Figure 2 It is a schematic rear view of the structure of the present invention;

[0034] Figure 3 It is a schematic front view of the structure of the main measuring ruler of the present invention;

[0035] Figure 4 It is an enlarged schematic diagram of the structure of the front fulcrum device of the present invention;

[0036] Figure 5 It is a schematic structural diagram of the anchor point device of the front fulcrum device of the present invention;

[0037] Figure 6 It is an enlarged schematic diagram of the slot structure of the front fulcrum device of the present invention;

[0038] Figure 7 It is a schematic front cross-sectional view of the structure of the front fulcrum device of the present invention.

[0039] In the figure: 1, main body measuring ruler; 2-5, front fulcrum device; 6-9, rear fulcrum device; 2, anchor device of the front fulcrum device; 3, anchor plate of the front fulcrum device; 4, sleeve box of the front fulcrum device; 5, slot of the front fulcrum device; 6, anchor device of the rear fulcrum device; 7, anchor plate of the rear fulcrum device; 8, sleeve box of the rear fulcrum device; 9, slot of the rear fulcrum device. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] See also Figure 1-7The present invention provides a technical solution: a pre-work rapid measurement device for a steel bar protective layer, comprising a main measuring ruler 1, an anchor device 2 of a front fulcrum device and an anchor plate 3 of the front fulcrum device, characterized in that: the main measuring ruler 1 is provided with a front fulcrum device and a rear fulcrum device, the front fulcrum device is composed of the anchor device 2 of the front fulcrum device, the anchor plate 3 of the front fulcrum device, a sleeve box 4 of the front fulcrum device and a slot 5 of the front fulcrum device, the front fulcrum device is composed of the anchor device 6 of the rear fulcrum device, the anchor plate 7 of the rear fulcrum device, a sleeve box 8 of the rear fulcrum device and a slot 9 of the rear fulcrum device, the sleeve box 4 of the front fulcrum device is provided on the left side of the main measuring ruler 1, and the sleeve box 4 of the front fulcrum device An anchor plate 3 of a front fulcrum device is arranged at the upper end of the box 4, the anchor plate 3 of the front fulcrum device is threadedly connected with the anchor device 2 of the front fulcrum device, and the bottom end of the anchor device 2 of the front fulcrum device is attached to the upper end of the main measuring ruler 1, a card slot 5 of the front fulcrum device is arranged at the bottom end of the sleeve box 4 of the front fulcrum device, a sleeve box 8 of a rear fulcrum device is sleeved on the right side of the main measuring ruler 1, and an anchor plate 7 of the rear fulcrum device is arranged at the upper end of the sleeve box 8 of the rear fulcrum device, the anchor plate 7 of the rear fulcrum device is threadedly connected with the anchor device 6 of the rear fulcrum device, and the bottom end of the anchor device 6 of the rear fulcrum device is attached to the upper end of the main measuring ruler 1, and a card slot 9 of the rear fulcrum device is arranged at the bottom end of the sleeve box 8 of the rear fulcrum device.

[0042] Example:

[0043] Step 1: Carry out construction according to the drawings, tie the steel bars and formwork, and install the pre-construction measuring device for the steel bar protection layer. The rear fulcrum device is first installed into the main measuring ruler through the sleeve box and anchored through the anchor device. The front fulcrum device is first installed into the main measuring ruler through the sleeve box and anchored through the anchor device;

[0044] Step 2: Determine the steel bar protection layer size requirements according to the design requirements, and adjust the front support device so that the front end distance is consistent with the steel bar protection layer size;

[0045] Step 3: Calculate the size on site based on the positive and negative difference requirements of the steel bar protection layer plus the steel bar size, and adjust the rear fulcrum device so that the distance between the front fulcrum device and the rear fulcrum device is consistent with the calculated size.

[0046] Step 4: Push the front end of the pre-work measuring device for the steel bar protection layer to the template to see whether the steel bar can be slotted in the middle of the front and rear fulcrum devices of the pre-work measuring device for the steel bar protection layer. If the steel bar is in the middle of the front and rear fulcrum devices of the pre-work measuring device for the steel bar protection layer, it means that the steel bar protection layer meets the requirements. If the steel bar is before the front fulcrum device of the pre-work measuring device for the steel bar protection layer, it means that the steel bar protection layer is small. If the steel bar is after the rear fulcrum device of the pre-work measuring device for the steel bar protection layer, it means that the steel bar protection layer is large.

[0047] Step 5: Adjust the steel bar protection layer according to the measurement results so that the steel bar protection layer meets the requirements.

[0048] Furthermore, a scale is provided on the left side of the front end of the main measuring ruler 1, and the scale is a standard scale, which is conducive to adjusting the position according to needs and facilitates more accurate detection.

[0049] Furthermore, a round hole is provided at the right side of the front end of the main measuring ruler 1, and the inner wall of the round hole is smooth, which is conducive to bolting a rope and is convenient for hanging on the body and carrying.

[0050] Furthermore, the front fulcrum device and the rear fulcrum device are arranged in parallel, and the front fulcrum device is placed on the left of the rear fulcrum device, which is conducive to determining the positions of the front fulcrum device and the rear fulcrum device according to needs and facilitates adjusting the distance.

[0051] Furthermore, the anchor device 2 of the front fulcrum device and the anchor device 6 of the rear fulcrum device are both provided with external threads, and the anchor plate 3 of the front fulcrum device and the anchor plate 7 of the rear fulcrum device are internally provided with internal threads corresponding to the external threads, which is conducive to driving the anchor device 2 of the front fulcrum device and the anchor device 6 of the rear fulcrum device to rise and fall stably, and is convenient for fixing the positions of the sleeve box 4 of the front fulcrum device and the sleeve box 8 of the rear fulcrum device.

[0052] Furthermore, the clamping slot 5 of the front fulcrum device and the clamping slot 9 of the rear fulcrum device are both arranged in the shape of hexagonal prisms, which is conducive to fitting and improves accuracy.

[0053] Furthermore, the measurement steps need to be based on the steel bar protection layer size and positive and negative difference requirements, and the steel bar size is also required, which is conducive to ensuring accuracy and facilitating adaptation to different steel bar protection layers.

[0054] Furthermore, the measurement steps are not limited by changes in the steel bar protective layer and are not limited by the form of the structure, which is beneficial to greatly shorten the operation time, save labor costs, and improve construction efficiency.

[0055] Furthermore, the measurement procedure is applicable to the measurement of any concrete construction protective layer of bridge engineering and any concrete construction protective layer of building construction and municipal engineering, which is conducive to safe and reliable stress bearing and has a wide range of applications.

[0056] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for rapid pre-construction measurement of a steel bar protective layer, applied to a device for rapid pre-construction measurement of a steel bar protective layer, characterized in that: The specific steps include: Step 1: The rear fulcrum device and the front fulcrum device are successively installed into the main measuring ruler through the sleeve box, and anchored through the anchor device; Step 2: Adjust and fix the front support device according to the size of the steel bar protective layer; Step 3: According to the requirements of the positive and negative difference of the steel bar protective layer plus the steel bar size, adjust the rear fulcrum device and fix it; Step 4: Check whether the steel bar can be slotted between the rear support device and the front support device on the main measuring ruler; Step 5: Adjust the steel bar protection layer according to the measurement results; The invention relates to a pre-construction rapid measurement device for a steel bar protective layer, comprising a main measuring ruler (1), an anchor device (2) of a front fulcrum device and an anchor plate (3) of the front fulcrum device. The main measuring ruler (1) is provided with a front fulcrum device and a rear fulcrum device. The front fulcrum device is composed of an anchor device (2) of the front fulcrum device, an anchor plate (3) of the front fulcrum device, a sleeve (4) of the front fulcrum device and a slot (5) of the front fulcrum device. The front fulcrum device is composed of an anchor device (6) of the rear fulcrum device, an anchor plate (7) of the rear fulcrum device, a sleeve (8) of the rear fulcrum device and a slot (9) of the rear fulcrum device. The sleeve (4) of the front fulcrum device is provided on the left side of the main measuring ruler (1), and a front fulcrum device is provided on the upper end of the sleeve (4) of the front fulcrum device. The invention relates to an anchor plate (3) of a device, wherein the anchor plate (3) of the front fulcrum device is threadedly connected to the anchor device (2) of the front fulcrum device, and the bottom end of the anchor device (2) of the front fulcrum device is attached to the upper end of the main measuring ruler (1), the bottom end of the sleeve (4) of the front fulcrum device is provided with a slot (5) of the front fulcrum device, the right side of the main measuring ruler (1) is sleeved with a sleeve (8) of the rear fulcrum device, and the upper end of the sleeve (8) of the rear fulcrum device is provided with an anchor plate (7) of the rear fulcrum device, the anchor plate (7) of the rear fulcrum device is threadedly connected to the anchor device (6) of the rear fulcrum device, and the bottom end of the anchor device (6) of the rear fulcrum device is attached to the upper end of the main measuring ruler (1), and the bottom end of the sleeve (8) of the rear fulcrum device is provided with a slot (9) of the rear fulcrum device.

2. A method for rapid pre-construction measurement of a steel bar protective layer according to claim 1, characterized in that: In the above-mentioned device for rapid pre-construction measurement of steel bar protective layer, The main measuring ruler (1) is provided with a scale on the left side of the front end, and the scale is a standard scale; A circular hole is provided on the right side of the front end of the main measuring ruler (1), and the inner wall of the circular hole is smooth; The front fulcrum device and the rear fulcrum device are arranged in parallel, and the front fulcrum device is placed on the left of the rear fulcrum device; The anchor device (2) of the front fulcrum device and the anchor device (6) of the rear fulcrum device are both provided with external threads, and the anchor plates (3) of the front fulcrum device and the anchor plates (7) of the rear fulcrum device are internally provided with internal threads corresponding to the external threads.

Images