Lightweight I-shaped steel and production roller thereof

Abstract

The utility model relates to the technical field of hot-rolled section steel, and particularly discloses a lightweight I-shaped steel and a production roller thereof, which comprises two wing plates with upper and lower surfaces arranged in parallel, and a web vertically connected between the two wing plates, the height and / or the width of the light-weight I-shaped steel is larger than that of a replaced standard part, the thickness of the web and / or the thickness of the wing plate are smaller than that of the replaced standard part, the difference value between the height and the width of the light-weight I-shaped steel and the standard part is 0-40 mm, the difference value between the width and the standard part is 0-30 mm, and the variation of the section modulus Wx of the light-weight I-shaped steel is kept within the range of + / -10% compared with the variation of the standard part. The cross-sectional area is reduced compared with a standard part; the production roller is used for producing the light-weight I-shaped steel, and the shape and the size of the production roller are matched with those of the light-weight I-shaped steel. By adopting the technical scheme provided by the utility model, the technical problems of low technical index and material waste when the hot-rolled common I-shaped steel in the prior art is applied to tunnel engineering can be solved, and the quality improvement and material reduction are realized.

Description

Technical Field

[0001] The utility model relates to the technical field of hot-rolled steel sections, in particular to a lightweight chemical steel section and a production roller thereof. Background Art

[0002] Hot-rolled ordinary I-beams, as an important type of steel, have been widely used in many fields such as construction, bridges, manufacturing and underground engineering, especially in tunnel construction. In tunnel engineering, hot-rolled ordinary I-beams are widely used in supporting structural components due to their unique structural characteristics, including: supporting frame structure, as the support system of the initial support wall of the tunnel, such as arch frame, providing the necessary rigidity and stability; lining reinforcement, spraying concrete on the arch frame as the supporting frame structure to form the tunnel lining. At this time, the I-beams serve as reinforcement components of the tunnel lining, which can improve the overall strength of the structure and resist surrounding rock pressure and water pressure.

[0003] Hot-rolled ordinary I-beam is a standard part. The technical standard of hot-rolled ordinary I-beam in my country was introduced in the 1950s. It has been used since it was domestically produced. The main dimensions and technical indicators have not changed in the past 70 years. For specific dimensions and technical indicators, please refer to the national standard "GB / T 706-2016 Hot-rolled Steel". Due to the limitations of steel production technology, equipment and product concepts at that time, hot-rolled ordinary I-beams generally have the defects of "thick limbs and short legs" with narrow width and too thick plates. It is an inefficient steel with unreasonable cross-section distribution. Therefore, the application fields of hot-rolled ordinary I-beams are getting fewer and fewer, and H-beams are replacing them. H-beams are widely used in building structures with their reasonable cross-section and better cross-section moment of inertia.

[0004] However, in tunnel engineering, hot-rolled ordinary I-beams, especially standard 14#~25# hot-rolled ordinary I-beams, are still irreplaceable due to their good diagonal leg stiffness and unique specifications and dimensions. However, I-beams used for tunnel lining reinforcement have always been hot-rolled ordinary I-beams, and no special design has been made for the I-beams according to the characteristics of the tunnel engineering environment, resulting in the weak axis section modulus W of the I-beams. y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y The technical indicators such as steel structure and structure are low, and the unreasonable cross-sectional size of I-beams leads to an increase in steel consumption, resulting in material waste, and is not in line with the requirements of the era of low-carbon emission reduction.

[0005] Therefore, it is urgent to optimize and improve the hot-rolled I-beams to adapt to tunnel engineering, so as to improve the technical indicators of the hot-rolled I-beams and reduce the steel usage of the hot-rolled I-beams. Utility Model Content

[0006] The utility model aims to provide a lightweight I-beam and a production roller thereof, so as to solve the technical problems of low technical index and waste of materials when the conventional hot-rolled ordinary I-beam is applied in tunnel engineering.

[0007] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0008] A lightweight chemical beam steel comprises two wing plates whose upper and lower surfaces are arranged parallel to each other, and a web plate vertically connected to the middle position of the two wing plates; the height and / or width of the lightweight chemical beam steel is greater than the standard part replaced, the thickness of the web plate and / or the wing plate is less than the standard part replaced, and the strong axis section modulus W of the lightweight chemical beam steel is x The variation compared to the standard part is kept within ±10%, and the cross-sectional area is reduced compared to the standard part.

[0009] Preferably, as an improvement, the height difference between the lightweight chemical steel beam and the standard part is 0≤Δh≤40mm, and the width difference between the lightweight chemical steel beam and the standard part is 0≤Δb≤30mm.

[0010] Preferably, as an improvement, the height difference between the lightweight chemical steel beam and the standard part is 0≤Δh≤35mm.

[0011] Preferably, as an improvement, the height difference between the lightweight chemical steel beam and the standard part is 0≤Δh≤30mm.

[0012] Preferably, as an improvement, the height and width of the lightweight cross-section steel are both greater than the replaced standard parts, and the thickness of the web and wing plates are both less than the replaced standard parts.

[0013] Preferably, as an improvement, the thickness of the web has a minimum value d min , and the minimum value d min Related to the height h of lightweight chemical steel, d min =1.6872ln(h)﹣4.5772.

[0014] Preferably, as an improvement, the thickness of the web is d min ≤d≤1.8d min , the thickness of the wing plate is d≤t≤2d, the slope of the wing plate is 2% to 16.7%, and the slope of the wing plate is positively correlated with the thickness of the wing plate.

[0015] The principle and beneficial effects of this program:

[0016] 1. This solution can improve other technical indicators while meeting the design requirements for the main technical indicators:

[0017] Since the I-beams used for tunnel lining reinforcement have their own unique sprayed concrete coating conditions, concrete has a strong restraining effect on the I-beams, which is similar to the strengthening mechanism of steel component performance in steel-reinforced concrete beams and columns. Therefore, the I-beams used for tunnel lining reinforcement can be designed to be thinner. Under the restraint of concrete, even if the I-beams are thinned, they can still meet the stability requirements, thereby ensuring that the quality of the tunnel lining meets the requirements.

[0018] Therefore, this scheme adopts the design concept of "wide limbs and thin walls" for steel structures. Based on the cross-sectional dimensions of standard 14#~25# hot-rolled ordinary I-beams, the cross-sectional dimensions are optimized and improved. Specifically, the height and / or width of the lightweight I-beam are greater than the replaced standard parts, and the thickness of the web and / or wing plate is less than the replaced standard parts. According to the experimental data of Experimental Examples 1 to 3, it can be seen that this scheme can improve the main technical indicators - strong axis section modulus W x To meet the design requirements, to ensure that the bending performance of the strong axis meets the design requirements, so that other technical indicators - weak axis section modulus W y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y It can be improved in a certain amount and degree, so that the bending resistance, bidirectional stiffness and stability of the weak axis can be improved. Therefore, this scheme can improve the comprehensive technical indicators of lightweight chemical steel beams, so that the lightweight chemical steel beams with optimized and improved cross-sectional dimensions can be more suitable for the use environment of tunnel engineering.

[0019] Specifically, lightweight steel beams are used in tunnel engineering. Due to the arched structure of the tunnel, lightweight steel beams play the role of both beams and columns. The stiffness of the column is proportional to the radius of inertia. When other conditions remain unchanged, the increase in the radius of inertia of the lightweight steel beam can increase the stiffness of both sides of the lightweight steel beam arch frame, thereby reducing the instability rate of the lightweight steel beam arch frame at the tunnel wall. The stiffness of the beam and the weak axis moment of inertia I y When other conditions remain unchanged, the weak axis inertia moment I of lightweight chemical steel y Lifting can improve the lateral stiffness of the arch of the lightweight chemical steel arch frame, improve the overall stability, and thus reduce the rollover probability of the lightweight chemical steel arch frame. In addition, the deflection of the beam and the moment of inertia of the strong axis I x Inversely proportional, when other conditions remain unchanged, the strong axis moment of inertia I x The reinforcement can reduce the deflection of the beam, thereby reducing the crown deformation of the lightweight chemical steel arch frame, and then controlling the settlement of the tunnel surrounding rock.

[0020] In the current tunnel design and construction process, it is usually necessary to increase the lateral support of the hot-rolled ordinary I-beam arch frame to improve the overall stability and prevent the hot-rolled ordinary I-beam arch frame from tipping over. This method leads to an increase in the overall steel consumption and construction volume, which in turn leads to an increase in costs. In order to improve the strong axis stiffness of the arch crown of the hot-rolled ordinary I-beam arch frame, thereby controlling the sinking of the tunnel surrounding rock, it is usually necessary to increase the density of the hot-rolled ordinary I-beam arch frame, which leads to a further increase in the overall steel consumption and further increases the construction cost. These methods are conventional means in this field. Those skilled in the art have not thought of optimizing and improving the cross-sectional dimensions of the hot-rolled ordinary I-beam to increase the moment of inertia of the section, thereby increasing the stiffness and reducing the deflection to achieve a better construction effect. The inventor of this scheme accidentally discovered in the process of repeatedly studying the cross-sectional dimension optimization and improvement scheme of the hot-rolled ordinary I-beam that the lightweight I-beam obtained after the cross-sectional dimension optimization and improvement of this scheme, while ensuring the strong axis modulus W x Under the condition of meeting the design requirements, its inertia radius and moment of inertia can be improved, thereby increasing rigidity and reducing deflection to achieve better construction results. Compared with the conventional means in this field, this solution is more economical and efficient. From the feedback, engineering and technical personnel generally believe that this solution is unexpected and enriches their technical means of controlling overall stability and surrounding rock settlement.

[0021] 2. This solution can reduce the amount of steel used and avoid material waste:

[0022] This scheme optimizes and improves the cross-sectional dimensions of standard 14#~25# hot-rolled ordinary I-beams, which can effectively reduce the cross-sectional area of ​​lightweight I-beams and reduce the steel density of 7.85g / cm2 specified in the national standard "GB / T 706-2016 Hot-rolled Steel" 3 The theoretical density of hot-rolled ordinary I-beams and lightweight chemical steel is calculated according to the formula of theoretical weight = theoretical density × theoretical volume. The length of the lightweight chemical steel is taken as 1m, and the theoretical weight is proportional to the cross-sectional area. This proves that after reducing the cross-sectional area of ​​the lightweight chemical steel, this scheme can effectively reduce the theoretical weight (meter weight) of the lightweight chemical steel, thereby achieving the lightweighting of hot-rolled ordinary I-beams, reducing the amount of steel used to avoid material waste, and meeting the requirements of the era of low-carbon emission reduction.

[0023] For example, the cross-sectional dimensions of the standard 14# hot-rolled ordinary I-beam are optimized and improved, so that the optimized and improved lightweight I-beam is 20.1% lighter than the standard part. According to the national standard "GB / T 706-2016 Hot-rolled Steel", the standard 14# hot-rolled ordinary I-beam is 16.9Kg / m. Calculated at a price of 4.5 yuan per kilogram of steel, the steel cost saving is 16.9×20.1%×4.5=15.29 yuan / m. At this time, the additional cost of civil engineering is about 8.65 yuan / m, and the comprehensive cost of the I-beam arch is reduced by 15.29-8.65=6.64 yuan / m, and the comprehensive cost reduction ratio can reach more than 8%. If the comprehensive cost of the I-beam arch of a tunnel is originally 100 million yuan, the I-beam improved by this scheme can save more than 8 million yuan, with significant economic effects.

[0024] To sum up, this scheme can achieve the technical effect of "improving quality and reducing materials", specifically: on the premise that the main technical indicators meet the design requirements, improve other technical indicators, reduce the amount of steel used, and avoid material waste.

[0025] It should be noted that the lightweight I-beam of the present application is larger in height and / or width, and thinner in web and / or wing thickness than the hot-rolled ordinary I-beam of the prior art that it replaces, thereby achieving the technical effect of "improving quality and reducing materials", which is different from the lightweight I-beam of the prior art. Compared with hot-rolled ordinary I-beams, at the same height (i.e., the corresponding model), although the lightweight I-beam has a wider flange, thinner thickness, and lighter weight, its technical indicators are significantly reduced, which is completely different from the improvement of this solution, and it is also impossible to achieve the technical effect that this solution can achieve. Moreover, for many years, there has been no actual production and demand for lightweight I-beams in the market, and only the standards remain, which are no longer of practical significance.

[0026] 3. This solution can adapt to various personalized design requirements:

[0027] Although the national standard "GB / T 706-2016 Hot-rolled Steel" stipulates the strong axis section modulus W of various types of hot-rolled ordinary I-beams x However, in the process of structural design, the designer will adjust the strong axis section modulus W of the I-beam according to the actual situation of the project. x After some adjustments, this scheme will make the strong axis section modulus W of the lightweight chemical steel x Compared with standard parts, the variation is kept within the range of ±10%, which can adapt to various personalized design needs while meeting the design requirements.

[0028] 4. This solution can improve the tunnel support effect and reduce the overall steel consumption:

[0029] In this solution, the wing width of the lightweight chemical steel is greater than the standard part it replaces, which increases the contact area between the wing and the surrounding rock, and can provide a better support effect on the surrounding rock, thereby improving the support effect of the tunnel support structure and ensuring the quality of the project. From another perspective, the support effect of a single lightweight chemical steel on the surrounding rock is optimized, which can reduce the layout density of the lightweight chemical steel of the tunnel support structure to a certain extent, thereby further reducing the overall steel consumption and reducing the overall cost.

[0030] 5. This solution can achieve comprehensive cost reduction and ensure the quality of concrete spraying:

[0031] This scheme controls the difference between the height of the lightweight chemical steel and the standard parts within the range of 0 to 40 mm, and controls the difference between the width of the lightweight chemical steel and the standard parts within the range of 0 to 30 mm. According to the experimental data of Experimental Example 6, it can be seen that the technical effect of reducing the amount of steel used in the lightweight chemical steel can be achieved, and the civil construction cost of the lightweight chemical steel arch frame can be controlled within a reasonable range, so that the comprehensive cost reduction ratio of the lightweight chemical steel arch frame can reach more than 8%, achieving significant economic value; at the same time, the concrete spraying quality of the lightweight chemical steel arch frame is guaranteed, thereby ensuring the construction quality of the tunnel lining.

[0032] If the height difference between the lightweight chemical steel and the standard parts is too large, greater than 40mm, although the steel consumption of the lightweight chemical steel can be reduced to a certain extent, it will lead to a significant increase in the amount of tunnel excavation and shotcrete, resulting in a significant increase in the civil construction cost of the lightweight chemical steel arch frame, thereby increasing the overall construction cost. In addition, the large difference between the height of the lightweight chemical steel and the standard parts will also bring about the instability of the web plate during the manufacturing process of the lightweight chemical steel and the increase in the overall instability rate during the arch frame processing.

[0033] If the difference between the width of the lightweight chemical steel and the standard parts is too large, greater than 30mm, although the steel consumption of the lightweight chemical steel can be reduced to a certain extent, it will bring difficulties in quality control during the shotcrete process of the lightweight chemical steel arch frame, and easily lead to the concrete filling of the lightweight chemical steel arch frame close to the surrounding rock side is not full, and the concrete cannot completely cover the lightweight chemical steel arch frame. The concrete cannot play a restraining role on the lightweight chemical steel in the exposed part of the lightweight chemical steel arch frame, and thus cannot play a reinforcing mechanism for this part of the lightweight chemical steel, resulting in a decrease in the construction quality of the tunnel lining. In addition, the large difference between the width of the lightweight chemical steel and the standard parts will also bring about adverse effects such as reduced plate stability during the manufacturing process of the lightweight chemical steel and increased overall instability rate during the arch frame processing.

[0034] On the basis of 0-40mm, the maximum value of the difference between the height of lightweight chemical steel and the standard part is reduced to 35mm, which can effectively improve the height and width ratio balance of lightweight chemical steel while achieving the technical effect of "improving quality and reducing materials", thereby improving the plate stability during the manufacturing process of lightweight chemical steel and reducing the overall instability rate during the arch processing. According to the experimental data of Experimental Example 5, this scheme has a certain degree of reduction in the effect of reducing the steel consumption of lightweight chemical steel, and the civil construction cost of the lightweight chemical steel arch frame has not changed much, so that the comprehensive cost reduction ratio of the lightweight chemical steel arch frame can reach more than 7%, which has obvious economic value.

[0035] Based on 0 to 35 mm, this solution further reduces the maximum value of the difference between the height of lightweight chemical steel and the standard parts to 30 mm, which can further improve the height and width ratio balance of lightweight chemical steel while achieving the technical effect of "improving quality and reducing materials", thereby further improving the plate stability during the manufacturing process of lightweight chemical steel and reducing the overall instability rate during the arch frame processing. According to the experimental data of Experimental Example 4, this solution has a further reduction effect on the reduction of steel consumption of lightweight chemical steel, and the civil construction cost of lightweight chemical steel arch frame remains unchanged, so that the comprehensive cost reduction ratio of lightweight chemical steel arch frame can reach more than 6%, which has certain economic value.

[0036] 6. This solution can ensure the proportion balance between height, width and back, and achieve better "quality improvement and material reduction effect":

[0037] In this solution, the height and width of the lightweight I-beam are both greater than the replaced standard parts, and the thickness of the web and the thickness of the wing are both less than the replaced standard parts. Compared with the method of "only the height or width of the I-beam is greater than the replaced standard parts, and only the thickness of the web or the wing is less than the replaced standard parts", it can effectively improve the height and width of the lightweight I-beam and the proportional balance between the thickness of the web and the wing, which is not only conducive to ensuring the rolling quality of the lightweight I-beam, but also conducive to ensuring the overall stability of the lightweight I-beam arch, thereby ensuring that the lightweight I-beam meets the use requirements of tunnel engineering. In addition, the experimental data of Experimental Examples 1 to 3 show that the optimization and improvement method of double increase and double reduction can achieve a better technical effect of "improving quality and reducing materials" than the optimization and improvement methods of single increase and single reduction, single increase and double reduction, and double increase and single reduction.

[0038] 7. This scheme can effectively meet the shear resistance requirements of tunnel engineering:

[0039] Since the use environment of tunnel engineering does not require high shear resistance of lightweight chemical steel, the thickness of the web in this solution is smaller than the standard part it replaces, and the minimum thickness of the web is set to d min=1.6872ln(h)-4.5772, which can achieve the above-mentioned technical effect of "improving quality and reducing materials", not only meet the technical requirements of steel production, but also effectively meet the shear resistance requirements of lightweight chemical steel in the use environment of tunnel engineering. If the thickness of the web is too small, less than the minimum value d min , which will cause the shear strength and overall stability of the lightweight chemical steel to be greatly reduced, causing the tunnel support structure (lightweight chemical steel arch frame) to be easily twisted, buckled or broken when subjected to stress, affecting the bearing capacity and service life of the tunnel support structure (lightweight chemical steel arch frame).

[0040] 8. This solution can achieve the technical effect of "improving quality and reducing materials" under the premise of ensuring quality:

[0041] In this solution, the thickness of the web is set to d min ≤d≤1.8d min , which can ensure that the shear resistance of lightweight chemical steel meets the use requirements of tunnel engineering, and at the same time improve the technical effect of "improving quality and reducing materials" of lightweight chemical steel. As mentioned above, the thickness of the web is set to be no less than d min , which can ensure the shear strength and overall stability of the lightweight steel beam, thereby preventing the tunnel support structure (lightweight steel beam arch frame) from twisting, buckling or breaking when subjected to force, improving the bearing capacity of the tunnel support structure (lightweight steel beam arch frame) and extending the service life of the tunnel support structure (lightweight steel beam arch frame). The thickness of the web is set to no more than 1.8d min Under the premise of ensuring quality, the thickness of the web can be guaranteed to be sufficiently reduced, thereby better achieving the technical effect of "improving quality and reducing material".

[0042] 9. This solution can ensure the yield rate during production and avoid distortion:

[0043] This solution sets the thickness of the wing plate to d≤t≤2d, which can effectively balance the thickness ratio of the wing plate and the web plate, ensure the yield rate of lightweight chemical steel during production and manufacturing, and avoid the distortion of lightweight chemical steel during transportation and use. If the thickness of the wing plate is too small, less than the thickness of the web plate, the wing plate is prone to wave and deformation when the steel billet is hot-rolled by the roller during the production process, resulting in a decrease in the yield rate of lightweight chemical steel, or even failure to produce. If the thickness of the wing plate is too large, greater than twice the thickness of the web plate, the thickness ratio of the wing plate to the web plate is unbalanced, and it is easy to distort and deform during the transportation process after hot rolling, further resulting in a decrease in the yield rate of lightweight chemical steel, or even failure to produce; and the finished lightweight chemical steel is more likely to be distorted and deformed during transportation and use than the I-beam with a coordinated thickness ratio of the wing plate and the web plate, resulting in the lightweight chemical steel failing to meet the requirements of engineering use, or affecting the quality of the project after use.

[0044] 10. This solution can improve the requirements of the tunnel support structure on lateral stiffness:

[0045] This solution sets the slope of the wing plate to 2% to 16.7%, which remains unchanged or decreases compared to the 16.7% specified in the national standard "GB / T 706-2016 Hot-rolled Steel". The reduced slope of the wing plate can make the inner side of the wing plate closer to perpendicular to the web, thereby increasing the effective width of the wing plate. For tunnel support structures that require greater lateral support, it can significantly improve the lateral bearing capacity and stability of the tunnel support structure and improve the requirements of the tunnel support structure for lateral stiffness. In addition, the wing plate that is closer to vertical can improve the stress distribution and reduce the local stress concentration caused by the tilt of the wing plate. For tunnel support structures that bear complex loads and need to serve for a long time, it can effectively improve the overall safety and durability of the tunnel support structure.

[0046] 11. This solution can balance the ratio between the thickness and slope of the wing plate and reduce stress concentration:

[0047] This scheme sets the wing plate and the slope to be positively correlated with the thickness of the wing plate, that is, when the thickness of the wing plate takes a large value in the range of d to 2d, the slope of the wing plate also takes a large value in the range of 2% to 16.7%. Conversely, when the thickness of the wing plate takes a small value in the range of d to 2d, the slope of the wing plate also takes a small value in the range of 2% to 16.7%. In this way, the ratio between the thickness and slope of the wing plate can be made more balanced. The thicker wing plate thickness provides a basis for setting a larger wing plate slope. When the thickness of the wing plate is small, the corresponding reduction of the slope of the wing plate can ensure that the end of the wing plate has a certain thickness, which is conducive to the rolling forming of the lightweight chemical steel and ensures the structural strength of the lightweight chemical steel. In addition, as the thickness of the wing plate increases, the corresponding increase in the slope can be regarded as a fine-tuning of the structure, which helps to distribute the stress more evenly at the junction of the wing plate and the web, reduce the stress concentration phenomenon, and thus improve the fatigue resistance of the lightweight chemical steel and the stability of the overall structure.

[0048] A method for designing the cross-sectional dimensions of a lightweight chemical steel is provided, and is used to design the cross-sectional dimensions of the above-mentioned lightweight chemical steel, comprising the following steps:

[0049] Step 1, determine the height of the lightweight chemical steel: first determine the difference Δh between the height of the lightweight chemical steel and the standard part according to 0≤Δh≤40mm, then add Δh to the height h0 of the standard part to obtain the height h of the lightweight chemical steel, that is, the height h of the lightweight chemical steel = Δh + h0;

[0050] Step 2: Determine the minimum value of the web thickness: According to the minimum value of the web thickness is d min=1.6872ln(h)-4.5772, substitute the height h of the lightweight chemical steel into the calculation to obtain the minimum value d of the web thickness min ;

[0051] Step 3: Determine the thickness of the web: According to the thickness of the web as d min ≤d≤1.8d min , determine the thickness d of the web;

[0052] Step 4: Determine the thickness of the wing plate: According to the relationship between the thickness of the wing plate and the thickness of the web plate, d≤t≤2d, determine the thickness t of the wing plate;

[0053] Step 5: Determine the width of the lightweight chemical steel: According to the strong axis section modulus W of the lightweight chemical steel x Compared with the standard parts, the variation is kept within the range of ±10%. First, the strong axis section modulus W of the lightweight chemical steel is determined. x Then determine the slope of the wing plate within the range of 2% to 16.7%, determine the arc radius r at the connection between the wing plate and the web within the range of 7.5 to 10.0 mm, determine the arc radius r1 at the end of the wing plate within the range of 2.0 to 5.0 mm, and then according to the formula W x =2∫y 2 dA / h, substitute the height h of the lightweight chemical steel, the thickness d of the web, the thickness t of the wing plate, and the section modulus W of the lightweight chemical steel x , the slope of the wing plate, the arc radius r at the connection between the wing plate and the web, and the arc radius r1 at the end of the wing plate are calculated to obtain the width b of the lightweight chemical steel.

[0054] Preferably, as an improvement, the method further comprises the following steps:

[0055] Step 6. Verify the difference between the width of the lightweight chemical steel and the standard part: subtract the width b0 of the standard part from the width b of the lightweight chemical steel calculated in step 5 to obtain the difference Δb between the width of the lightweight chemical steel and the standard part, that is, the difference Δb between the width of the lightweight chemical steel and the standard part = b-b0. If the calculated Δb does not meet 0≤Δb≤30mm, redetermine the height h of the lightweight chemical steel, the thickness d of the web, the thickness t of the wing plate, and the width b of the lightweight chemical steel according to steps 1 to 5, and then recalculate Δb until the calculated Δb meets 0≤Δb≤30mm.

[0056] The principle and beneficial effects of this program:

[0057] 1. This scheme can achieve "improving quality and reducing materials": This scheme adopts the design concept of "wide limbs and thin walls" for steel structures. Based on the cross-sectional dimensions of standard 14#~25# hot-rolled ordinary I-beams, the height and / or width of the hot-rolled ordinary I-beams, as well as the thickness of the web and / or wing plates are optimized and improved to obtain a cross-sectional dimension of a lightweight I-beam, which can achieve the technical effect of "improving quality and reducing materials", specifically: on the premise that the main technical indicators meet the design requirements, other technical indicators are improved and the amount of steel used is reduced.

[0058] 2. This scheme can reduce the overall cost: This scheme determines the height of lightweight chemical steel according to the difference between the height of lightweight chemical steel and the standard part of 0≤Δh≤40mm, which can not only achieve the technical effect of "improving quality and reducing materials", but also control the civil construction cost within a reasonable range, thereby reducing the overall cost of arch construction and achieving the expected economic value. If the difference between the height of lightweight chemical steel and the standard part is too large, greater than 40mm, although the amount of steel used in lightweight chemical steel can be reduced to a certain extent, it will lead to a significant increase in the amount of tunnel excavation and shotcrete, resulting in a significant increase in civil construction costs, thereby increasing the overall cost of arch construction. In addition, if the height increment of lightweight chemical steel is too large, it will also bring about adverse effects such as unstable plate shape of the web during the manufacturing process of lightweight chemical steel and increased overall instability rate during arch processing.

[0059] 3. This solution can ensure the quality of lightweight chemical steel: in the main technical indicators - strong axis section modulus W x Under the premise of meeting the design requirements, theoretically, the thinner the web is, the less steel is needed. However, the thickness of the web has a minimum value. If the minimum value is exceeded, the lightweight chemical steel will have quality defects or even be scrapped. After many experiments, the inventors have obtained the value rule of the minimum value of the web thickness, that is, d min =1.6872ln(h)-4.5772, the minimum value of the web thickness is related to the height of the lightweight chemical steel. After the height of the lightweight chemical steel is determined, the minimum value of the web thickness is calculated according to the height of the lightweight chemical steel. When determining the web thickness, do not exceed the minimum value to ensure the quality of the lightweight chemical steel.

[0060] 4. This scheme can ensure the smooth production of lightweight chemical steel: This scheme is based on the thickness of the web as d min ≤d≤1.8d min To determine the thickness of the web, this can ensure that the lightweight chemical steel can be produced smoothly and the quality of the finished product of the lightweight chemical steel meets the engineering requirements, and can also achieve the expected technical effect of reducing the amount of steel used. min At this time, the roller is difficult to meet the production requirements and cannot produce a thickness less than d minLightweight chemical steel, and even if the roller can produce a thickness less than d min The quality of lightweight chemical steel cannot meet the requirements of tunnel engineering. If the thickness of the web is too large, greater than d min 1.8 times of that, although it can ensure the quality of lightweight chemical steel, it cannot achieve the expected technical effect of reducing the amount of steel used.

[0061] 5. This scheme can balance the thickness ratio of the wing plate and the web plate and reduce deformation: This scheme determines the thickness of the wing plate according to the relationship between the thickness of the wing plate and the thickness of the web plate, which is d≤t≤2d. It can effectively balance the thickness ratio of the wing plate and the web plate, ensure the yield rate of lightweight chemical steel during production and manufacturing, and avoid the distortion and deformation of lightweight chemical steel during transportation and use. If the thickness of the wing plate is too small, less than the thickness of the web plate, the wing plate is prone to wave and deformation when the steel billet is hot-rolled by the roller during the production process, resulting in a decrease in the yield rate of lightweight chemical steel. If the thickness of the wing plate is too large, greater than twice the thickness of the web plate, the thickness ratio of the wing plate to the web plate is unbalanced, and it is easy to distort and deform during the transportation process after hot rolling, further resulting in a decrease in the yield rate of lightweight chemical steel; and the finished lightweight chemical steel is more likely to distort and deform during transportation and use than the I-beam with a coordinated thickness ratio of the wing plate and the web plate, resulting in the lightweight chemical steel failing to meet the requirements of engineering use, or affecting the quality of the engineering after use.

[0062] 6. This solution can adapt to various personalized design requirements: Although the national standard "GB / T 706-2016 Hot-rolled Steel" stipulates the strong axis section modulus W of various types of hot-rolled ordinary I-beams x However, in the process of structural design, the designer will adjust the strong axis section modulus W of the I-beam according to the actual situation of the project. x After some adjustments, this scheme will make the strong axis section modulus W of the lightweight chemical steel x Compared with standard parts, the variation is kept within the range of ±10%, which can adapt to various personalized design needs while meeting the design requirements.

[0063] 7. This scheme can ensure the quality of concrete spraying of the arch frame: This scheme uses the difference between the width of the wing plate and the standard part as 0≤Δb≤30mm as the verification basis to finally determine the height h of the lightweight chemical steel, the thickness d of the web, the thickness t of the wing plate, and the width b of the lightweight chemical steel. It can not only achieve the technical effect of reducing the amount of steel used, but also ensure the quality of concrete spraying of the lightweight chemical steel arch frame, thereby ensuring the construction quality of the tunnel lining. If the difference between the width of the lightweight chemical steel and the standard part is too large, greater than 30mm, although it can reduce the amount of steel to a certain extent, it will bring difficulties in quality control during the spraying of concrete of the lightweight chemical steel arch frame, and it is easy to cause the concrete filling of the lightweight chemical steel arch frame close to the surrounding rock side to be insufficient, and the concrete cannot completely cover the lightweight chemical steel arch frame. Then the concrete cannot play a restraining role on the lightweight chemical steel in the exposed part of the lightweight chemical steel arch frame, and thus cannot play a reinforcing mechanism for this part of the lightweight chemical steel, resulting in a decrease in the construction quality of the tunnel lining. In addition, the large difference between the width of lightweight chemical steel beams and standard parts will also bring about adverse effects such as reduced plate shape stability during the manufacturing process of lightweight chemical steel beams and increased overall instability rate during arch frame processing.

[0064] A production roller for lightweight chemical steel is used to produce the above-mentioned lightweight chemical steel, and its shape and size match those of the lightweight chemical steel.

[0065] The principle and beneficial effects of this program:

[0066] This solution sets the shape and size of the production roll to match the shape and size of the lightweight chemical steel. The lightweight chemical steel rolled by the production roll has a cross-sectional size that meets the requirements of "the height and / or width of the lightweight chemical steel is greater than the standard part replaced, the thickness of the web and / or wing plate is less than the standard part replaced, and the strong axis section modulus W of the lightweight chemical steel is greater than the standard part replaced. x The optimization and improvement scheme of "the variation compared with the standard parts is kept within the range of ±10%, and the cross-sectional area is reduced compared with the standard parts" achieves the technical effect of "improving quality and reducing materials", thereby realizing the lightweighting of hot-rolled ordinary I-beams. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 It is a structural schematic diagram of the utility model lightweight chemical steel. DETAILED DESCRIPTION

[0068] The following is further described in detail through specific implementation methods:

[0069] The figure marks in the drawings of the specification include: web 1, wing plate 2, height h of lightweight chemical steel, width b of lightweight chemical steel, thickness d of web, thickness t of wing plate, arc radius r at the connection between wing plate and web, arc radius r1 at the end of wing plate.

[0070] This application mainly aims to improve the cross-sectional dimensions of 14# to 25# hot-rolled ordinary I-beams in the national standard "GB / T 706-2016 Hot-rolled Steel Sections".

[0071] Example 1

[0072] In this embodiment, based on the cross-sectional dimensions of small-sized hot-rolled ordinary I-beams, the height h and / or width b of the hot-rolled ordinary I-beams are increased, and the thickness d of the web and / or the thickness t of the wing are reduced, thereby obtaining a lightweight I-beam to replace the small-sized hot-rolled ordinary I-beams. For example, based on the cross-sectional dimensions of 14# hot-rolled ordinary I-beams, the height h and / or width b of the hot-rolled ordinary I-beams are increased, and the thickness d of the web and / or the thickness t of the wing are reduced, thereby obtaining a lightweight I-beam to replace the 14# hot-rolled ordinary I-beams.

[0073] The present application discloses a lightweight chemical steel. Figure 1 As shown, it includes two wing plates 2 whose upper and lower surfaces are parallel to each other, and a web 1 vertically connected to the middle of the two wing plates 2. The height h and / or width b of the lightweight chemical steel is greater than the standard part replaced, and the thickness d of the web and / or the thickness t of the wing plate is less than the standard part replaced; the strong axis section modulus W of the lightweight chemical steel x The variation compared to the standard part is kept within ±10%, and the cross-sectional area is reduced compared to the standard part.

[0074] When the height h and width b of the lightweight chemical steel are both greater than the replaced standard parts, and the thickness d of the web and the thickness t of the wing are both less than the replaced standard parts, the difference Δh between the height of the lightweight chemical steel and the replaced standard parts is in the range of 0≤Δh≤40mm, and the difference Δb between the width of the lightweight chemical steel and the replaced standard parts is in the range of 0≤Δb≤30mm. Specifically, Δh can be 0, 5mm, 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, etc., and Δb can be 0, 5mm, 10mm, 15mm, 20mm, 25mm, 30mm, etc.

[0075] The thickness d of the web has a minimum value d min , and the minimum value d min Related to the height h of lightweight chemical steel, d min =1.6872ln(h)-4.5772. The value range of the web thickness d is d min ≤d≤1.8d min The relationship between the thickness t of the wing plate and the thickness d of the web is d≤t≤2d, and the slope of the wing plate is 2% to 16.7%. Specifically, d can be d min , 1.3dmin , 1.5d min , 1.8d min Etc., t can be d, 1.5d, 2d, etc., and the slope of the wing can be 2%, 6%, 10%, 14%, 16.7%, etc.

[0076] The slope of the wing plate is positively correlated with the thickness t of the wing plate, that is, when the thickness t of the wing plate takes a larger value in the range of d to 2d, the slope of the wing plate also takes a larger value in the range of 2% to 16.7%. Conversely, when the thickness t of the wing plate takes a smaller value in the range of d to 2d, the slope of the wing plate also takes a smaller value in the range of 2% to 16.7%.

[0077] The arc radius r at the connection between the wing plate and the web plate is in the range of 7.5 to 10.0 mm, specifically 7.5 mm, 9.0 mm, 10.0 mm, etc. The arc radius r1 at the end of the wing plate is in the range of 2.0 to 5.0 mm, specifically 2.0 mm, 3.0 mm, 4.0 mm, etc.

[0078] Section modulus W of strong axis of lightweight chemical steel x Compared with the standard parts, the variation is kept within the range of ±10%. On the basis of meeting the design requirements, the designer can adjust the strong axis section modulus W of the lightweight chemical steel according to the actual project situation. x Adjustments are made to ensure that lightweight chemical steel can adapt to various personalized design requirements. Specifically, according to the actual situation of the project, the strong axis section modulus W of the lightweight chemical steel x The variation compared to the standard part can be ±10%, ±8%, ±5%, ±1%, etc.

[0079] Experimental Example 1

[0080] According to the national standard "GB / T 706-2016 Hot-rolled Steel Sections", the hot-rolled ordinary I-beam model 14# was selected as the basis for optimization, improvement and comparison of cross-sectional dimensions.

[0081] In this experimental example, for the convenience of calculation, the arc radius r at the connection between the wing plate and the web of all experimental groups remains unchanged compared with the standard 14# hot-rolled ordinary I-beam, and is 7.5 mm; the arc radius r1 at the end of the wing plate of all experimental groups is reduced compared with the standard 14# hot-rolled ordinary I-beam, and is 2.0 mm; the slope of the wing plate of all experimental groups is reduced compared with the standard 14# hot-rolled ordinary I-beam, and is 2%.

[0082]

[0083] The experimental data in Table 1 show that the height h and width b of the lightweight chemical beam are greater than the replaced standard parts, and the thickness d of the web and the thickness t of the wing are less than the replaced standard parts, which can achieve the best "quality improvement and material reduction" effect: the weight per meter is reduced by 20.1%, which is the best weight reduction effect among all experimental groups and can save the steel consumption to the maximum extent; the main technical indicators - strong axis section modulus W x Compared with the standard 14# hot-rolled ordinary I-beam, it increases by 2.0%, which can meet the design requirements. All other technical indicators - weak axis section modulus W y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y All of them have been improved to a certain extent, and the comprehensive technical indicators have been effectively improved.

[0084] (1) Experimental groups 1 to 4 adopted the optimization and improvement method of "single increase and single decrease":

[0085] Experimental group 1: h↑, b→, d↓, t→. Specifically, the height h of the lightweight chemical steel increases by 2 mm, which is in line with the increment range of 0 to 40 mm; the width b of the lightweight chemical steel remains unchanged at 80 mm; the thickness d of the web decreases from 5.5 mm to 4.6 mm, and the minimum value d of the web at this height is min =1.6872ln(142)-4.5772=3.8mm, which is consistent with d min ≤d≤1.8d min ; The thickness t of the wing plate remains unchanged at 9.1mm, which meets the condition of d≤t≤2d. At this time, the weight per meter of lightweight chemical steel is reduced by 4.1%; Main technical indicators - strong axis section modulus W x Compared with the standard 14# hot-rolled ordinary I-beam, it is increased by 1.0%, which can meet the design requirements. All other technical indicators - weak axis section modulus W y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y All of them have been improved to a certain extent, and the comprehensive technical indicators have been effectively improved; therefore, Experimental Group 1 can achieve the technical effect of "improving quality and reducing materials".

[0086] Experimental group 2: h↑, b→, d→, t↓. Specifically, the height h of the lightweight chemical steel increases by 40 mm, which is in line with the increment range of 0 to 40 mm; the width b of the lightweight chemical steel remains unchanged at 80 mm; the thickness d of the web remains unchanged at 5.5 mm, and the minimum value d of the web at this height is min =1.6872ln(180)-4.5772=4.2mm, which is consistent with dmin ≤d≤1.8d min ; The thickness t of the wing plate is reduced from 9.1mm to 5.5mm, which meets the requirement of d≤t≤2d. At this time, the weight per meter of lightweight chemical steel is reduced by 14.2%; Main technical indicators - strong axis section modulus W x Compared with the standard 14# hot-rolled ordinary I-beam, it is unchanged and can meet the design requirements. Some other technical indicators - strong axis moment of inertia I x , strong axis inertia radius i x There is a certain degree of improvement, and the comprehensive technical indicators can be improved; therefore, Experimental Group 2 can achieve the technical effect of "improving quality and reducing materials".

[0087] Experimental group 3: h→, b↑, d↓, t→. Specifically, the height h of the lightweight chemical steel is kept unchanged at 140 mm; the width b of the lightweight chemical steel is increased by 2 mm, which is in line with the increment range of 0 to 30 mm; the thickness d of the web is reduced from 5.5 mm to 4.6 mm, and the minimum value d of the web at this height is min =1.6872ln(140)-4.5772=3.8mm, which is consistent with d min ≤d≤1.8d min ; The thickness t of the wing plate remains unchanged at 9.1mm, meeting the condition of d≤t≤2d. At this time, the weight per meter of lightweight chemical steel is reduced by 3.0%; Main technical indicators - strong axis section modulus W x Compared with the standard 14# hot-rolled ordinary I-beam, it is increased by 1.0%, which can meet the design requirements. All other technical indicators - weak axis section modulus W y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y All of them have been improved to a certain extent, and the comprehensive technical indicators have been effectively improved; therefore, Experimental Group 3 can achieve the technical effect of "improving quality and reducing materials".

[0088] Experimental group 4: h→, b↑, d→, t↓. Specifically, the height h of the lightweight chemical steel is kept unchanged at 140 mm; the width b of the lightweight chemical steel is increased by 30 mm, which is in line with the increment range of 0 to 30 mm; the thickness d of the web is kept unchanged at 5.5 mm, and the minimum value d of the web at this height is min =1.6872ln(140)-4.5772=3.8mm, which is consistent with d min ≤d≤1.8d min ; The thickness t of the wing plate is reduced from 9.1mm to 6.2mm, which meets the requirement of d≤t≤2d. At this time, the weight per meter of lightweight chemical steel is reduced by 2.4%; Main technical indicators - strong axis section modulus W xCompared with the standard 14# hot-rolled ordinary I-beam, it is increased by 1.0%, which can meet the design requirements. All other technical indicators - weak axis section modulus W y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y All of them have been improved to a certain extent, and the comprehensive technical indicators have been effectively improved; therefore, Experimental Group 4 can achieve the technical effect of "improving quality and reducing materials".

[0089] (2) Experimental groups 5 and 6 adopted the optimization and improvement method of "single increase and double reduction":

[0090] Experimental group 5: h↑, b→, d↓, t↓. Specifically, the height h of the lightweight chemical steel increased by 24 mm, which is in line with the increment range of 0 to 40 mm; the width b of the lightweight chemical steel remained unchanged at 80 mm; the thickness d of the web decreased from 5.5 mm to 4.6 mm, and the minimum value d of the web at this height was min =1.6872ln(164)-4.5772=4.0mm, which is consistent with d min ≤d≤1.8d min ; The thickness t of the wing plate is reduced from 9.1mm to 7.0mm, which meets the requirement of d≤t≤2d. At this time, the weight per meter of lightweight chemical steel is reduced by 14.2%; Main technical indicators - strong axis section modulus W x Compared with the standard 14# hot-rolled ordinary I-beam, it is 1.0% larger, which can meet the design requirements. Some other technical indicators - strong axis moment of inertia I x , strong axis inertia radius i x , weak axis inertia radius i y There is a certain degree of improvement, and the comprehensive technical indicators can be improved; therefore, Experimental Group 5 can achieve the technical effect of "improving quality and reducing materials".

[0091] Experimental group 6: h→, b↑, d↓, t↓. Specifically, the height h of the lightweight chemical steel is kept unchanged at 140 mm; the width of the lightweight chemical steel is increased by 22 mm, which is in line with the increment range of 0 to 30 mm; the thickness d of the web is reduced from 5.5 mm to 4.6 mm, and the minimum value d of the web at this height is min =1.6872ln(140)-4.5772=3.8mm, which is consistent with d min ≤d≤1.8d min ; The thickness t of the wing plate is reduced from 9.1mm to 7.0mm, which meets the requirement of d≤t≤2d. At this time, the weight per meter of lightweight chemical steel is reduced by 4.7%; Main technical indicators - strong axis section modulus W xCompared with the standard 14# hot-rolled ordinary I-beam, it is increased by 1.0%, which can meet the design requirements. All other technical indicators - weak axis section modulus W y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y All of them have been improved to a certain extent, and the comprehensive technical indicators have been effectively improved; therefore, Experimental Group 6 can achieve the technical effect of "improving quality and reducing materials".

[0092] (3) Experimental groups 7 and 8 adopted the optimization and improvement method of "double increase and single reduction":

[0093] Experimental group 7: h↑, b↑, d↓, t→. Specifically, the height h of the lightweight chemical steel increases by 2 mm, which is in line with the increment range of 0 to 40 mm; the width b of the lightweight chemical steel increases by 2 mm, which is in line with the increment range of 0 to 30 mm; the thickness d of the web decreases from 5.5 mm to 4.6 mm, and the minimum value d of the web at this height is min =1.6872ln(142)-4.5772=3.8mm, which is consistent with d min ≤d≤1.8d min ; The thickness t of the wing plate remains unchanged at 9.1mm, which meets the condition of d≤t≤2d. At this time, the weight per meter of lightweight chemical steel is reduced by 2.4%; Main technical indicators - strong axis section modulus W x Compared with the standard 14# hot-rolled ordinary I-beam, it is 2.9% larger, which can meet the design requirements. All other technical indicators - weak axis section modulus W y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y All of them have been improved to a certain extent, and the comprehensive technical indicators have been effectively improved; therefore, Experimental Group 7 can achieve the technical effect of "improving quality and reducing materials".

[0094] Experimental group 8: h↑, b↑, d→, t↓. Specifically, the height h of the lightweight chemical steel increases by 20 mm, which is in line with the increment range of 0 to 40 mm; the width b of the lightweight chemical steel increases by 12 mm, which is in line with the increment range of 0 to 30 mm; the thickness d of the web remains unchanged at 5.5 mm, and the minimum value d of the web at this height is min =1.6872ln(160)-4.5772=4.0mm, which is consistent with d min ≤d≤1.8d min ; The thickness t of the wing plate is reduced from 9.1mm to 6.0mm, which meets the requirement of d≤t≤2d. At this time, the weight per meter of lightweight chemical steel is reduced by 8.9%; Main technical indicators - strong axis section modulus Wx Compared with the standard 14# hot-rolled ordinary I-beam, it is increased by 1.0%, which can meet the design requirements. All other technical indicators - weak axis section modulus W y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y All of them have been improved to a certain extent, and the comprehensive technical indicators have been effectively improved; therefore, Experimental Group 8 can achieve the technical effect of "improving quality and reducing materials".

[0095] (4) Experimental group 9 adopted the optimization and improvement method of "double increase and double reduction":

[0096] Experimental group 9: h↑, b↑, d↓, t↓. Specifically, the height h of the lightweight chemical steel increased by 40 mm, which is in line with the increment range of 0 to 40 mm; the width b of the lightweight chemical steel increased by 30 mm, which is in line with the increment range of 0 to 30 mm; the thickness d of the web decreased from 5.5 mm to 4.3 mm, and the minimum value d of the web at this height was min =1.6872ln(180)-4.5772=4.2mm, which is consistent with d min ≤d≤1.8d min ; The thickness t of the wing plate is reduced from 9.1mm to 4.3mm, which meets the requirement of d≤t≤2d. At this time, the weight per meter of lightweight chemical steel is reduced by 20.1%; Main technical indicators - strong axis section modulus W x Compared with the standard 14# hot-rolled ordinary I-beam, it is 2.0% larger, which can meet the design requirements. All other technical indicators - weak axis section modulus W y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y All of them have been improved to a certain extent, and the comprehensive technical indicators have been effectively improved; therefore, Experimental Group 9 can achieve the technical effect of "improving quality and reducing materials".

[0097] In summary, no matter whether the optimization and improvement method of "single increase and single reduction", "single increase and double reduction", "double increase and single reduction" or "double increase and double reduction" is adopted, the technical effect of "improving quality and reducing material" can be achieved, that is, the technical scheme of "the height h and / or width b of the lightweight I-beam is greater than the standard part it replaces, and the thickness d of the web and / or the thickness t of the wing plate is less than the standard part it replaces" is applied to the optimization and improvement of the cross-sectional dimensions of the standard part 14# hot-rolled ordinary I-beam, which can achieve the technical effect of "improving quality and reducing material".

[0098] Combining the experimental data of experimental group 2 and experimental group 10, it can be seen that when the height h of the lightweight chemical steel is greater than the standard part it replaces, the width b of the lightweight chemical steel remains unchanged, the thickness t of the wing plate decreases, and the thickness d of the web remains unchanged, the difference Δh between the height of the lightweight chemical steel and the standard part can be taken to a value outside the range of 0 to 40 mm, specifically 45 mm. That is, when the height h of the lightweight chemical steel is greater than the standard part it replaces, the width b of the lightweight chemical steel remains unchanged, the thickness t of the wing plate decreases, and the thickness d of the web remains unchanged, the difference Δh between the height of the lightweight chemical steel and the standard part ranges from 0 to 45 mm.

[0099] Combining the experimental data of experimental group 4 and experimental group 11, it can be seen that when the height h of the lightweight chemical steel is unchanged, the width b of the lightweight chemical steel is greater than the standard part it replaces, the thickness t of the wing plate is reduced, and the thickness d of the web plate is unchanged, the difference Δb between the width of the lightweight chemical steel and the standard part can be taken to a value outside the range of 0 to 30 mm, specifically 35 mm. That is, when the width b of the lightweight chemical steel is greater than the standard part it replaces, the height h of the lightweight chemical steel is unchanged, the thickness t of the wing plate is reduced, and the thickness d of the web plate is unchanged, the difference Δb between the width of the lightweight chemical steel and the standard part is in the range of 0 to 35 mm.

[0100] Therefore, in the case of "single increase and single decrease", and when the thickness d of the web is reduced, the difference Δh between the height of the lightweight chemical steel beam and the standard part is not limited by the value range of 0 to 40 mm, and can be greater than 40 mm. The difference Δb between the width of the lightweight chemical steel beam and the standard part is not limited by the value range of 0 to 30 mm, and can be greater than 30 mm.

[0101] Experimental Example 2

[0102] According to the national standard "GB / T 706-2016 Hot-rolled Steel Sections", the hot-rolled ordinary I-beam with model number 20a# was selected as the basis for optimization, improvement and comparison of cross-sectional dimensions.

[0103] In this experimental example, for the convenience of calculation, the arc radius r at the connection between the wing plate and the web of all experimental groups remains unchanged compared with the standard part 20a# hot-rolled ordinary I-beam, and is taken as 9.0 mm; the arc radius r1 at the end of the wing plate of experimental groups 1-9 is reduced compared with the standard part 20a# hot-rolled ordinary I-beam, and is taken as 3.0 mm; the arc radius r1 at the end of the wing plate of experimental groups 10 and 11 is reduced compared with the standard part 20a# hot-rolled ordinary I-beam, and is taken as 4.0 mm; the slope of the wing plate of all experimental groups is reduced compared with the standard part 20a# hot-rolled ordinary I-beam, and is taken as 4%.

[0104]

[0105] The experimental data in Table 2 show that the height h and width b of the lightweight chemical beam are greater than the replaced standard parts, and the thickness d of the web and the thickness t of the wing are less than the replaced standard parts, which can achieve the best "quality improvement and material reduction" effect: the weight per meter is reduced by 20.1%, which is the best weight reduction effect among all experimental groups and can save the steel consumption to the maximum extent; the main technical indicators - strong axis section modulus W x Compared with the standard 20a# hot-rolled ordinary I-beam, it remains unchanged and can meet the design requirements. All other technical indicators - weak axis section modulus W y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y All of them have been improved to a certain extent, and the comprehensive technical indicators have been effectively improved.

[0106] Experimental groups 1 to 4 adopted the optimization and improvement method of "single increase and single reduction", experimental groups 5 and 6 adopted the optimization and improvement method of "single increase and double reduction", experimental groups 7 and 8 adopted the optimization and improvement method of "double increase and single reduction", and experimental group 9 adopted the optimization and improvement method of "double increase and double reduction", all of which were able to achieve the technical effect of "improving quality and reducing materials", that is, the technical scheme of "the height h and / or width b of the lightweight I-beam is greater than the standard part it replaces, and the thickness d of the web and / or the thickness t of the wing plate is less than the standard part it replaces", which is applied to the optimization and improvement of the cross-sectional dimensions of the standard part 20a# hot-rolled ordinary I-beam, and can achieve the technical effect of "improving quality and reducing materials".

[0107] Experimental groups 10 and 11 show that, in the case of "single increase and single decrease", when the thickness d of the web is reduced, the difference Δh between the height of the lightweight chemical steel beam and the standard part is not limited by the value range of 0 to 40 mm, and can be greater than 40 mm. The difference Δb between the width of the lightweight chemical steel beam and the standard part is not limited by the value range of 0 to 30 mm, and can be greater than 30 mm.

[0108] Experimental Example 3

[0109] According to the national standard "GB / T 706-2016 Hot-rolled Steel Sections", the hot-rolled ordinary I-beam with model number 25a# was selected as the basis for optimization, improvement and comparison of cross-sectional dimensions.

[0110] In this experimental example, for the convenience of calculation, the arc radius r at the connection between the wing plate and the web of all experimental groups remains unchanged compared with the standard part 25a# hot-rolled ordinary I-beam, and is taken as 10.0 mm; the arc radius r1 at the end of the wing plate of all experimental groups is reduced compared with the standard part 25a# hot-rolled ordinary I-beam, and is taken as 4.0 mm; the slope of the wing plate of all experimental groups is reduced compared with the standard part 25a# hot-rolled ordinary I-beam, and is taken as 6%.

[0111]

[0112] The experimental data in Table 3 show that the height h and width b of the lightweight chemical beam are greater than the replaced standard parts, and the thickness d of the web and the thickness t of the wing are less than the replaced standard parts, which can achieve the best "quality improvement and material reduction" effect: the weight per meter is reduced by 19.9%, which is the best weight reduction effect among all experimental groups and can save the steel consumption to the maximum extent; the main technical indicators - strong axis section modulus W x Compared with the standard 25a# hot-rolled ordinary I-beam, it is reduced by 0.2%, which can meet the design requirements. All other technical indicators - weak axis section modulus W y , Strong axis moment of inertia I x 、Weak axis moment of inertia I y , strong axis inertia radius i x , weak axis inertia radius i y All of them have been improved to a certain extent, and the comprehensive technical indicators have been effectively improved.

[0113] Experimental groups 1 to 4 adopted the optimization and improvement method of "single increase and single reduction", experimental groups 5 and 6 adopted the optimization and improvement method of "single increase and double reduction", experimental groups 7 and 8 adopted the optimization and improvement method of "double increase and single reduction", and experimental group 9 adopted the optimization and improvement method of "double increase and double reduction", all of which were able to achieve the technical effect of "improving quality and reducing materials", that is, the technical scheme of "the height h and / or width b of the lightweight I-beam is greater than the standard part it replaces, and the thickness d of the web and / or the thickness t of the wing plate is less than the standard part it replaces" is applied to the optimization and improvement of the cross-sectional dimensions of the standard part 25a# hot-rolled ordinary I-beam, which can achieve the technical effect of "improving quality and reducing materials".

[0114] Experimental groups 10 and 11 show that, in the case of "single increase and single decrease", when the thickness d of the web is reduced, the difference Δh between the height of the lightweight chemical steel beam and the standard part is not limited by the value range of 0 to 40 mm, and can be greater than 40 mm. The difference Δb between the width of the lightweight chemical steel beam and the standard part is not limited by the value range of 0 to 30 mm, and can be greater than 30 mm.

[0115] Experimental Example 4

[0116] According to the national standard "GB / T 706-2016 Hot-rolled Steel Sections", the hot-rolled ordinary I-beams with models 14#, 20a#, and 25a# were selected as the basis, and the "double increase and double reduction" optimization and improvement method was adopted to optimize and improve their cross-sectional dimensions respectively, with the height increment being 0 to 30mm and the width increment being 0 to 30mm.

[0117]

[0118] The experimental data in Table 4 show that by adopting the optimization and improvement method of "double increase and double reduction", on the premise that the difference Δh between the height of lightweight chemical steel and the standard part is kept at 0-30mm, and the difference Δb between the width of lightweight chemical steel and the standard part is kept at 0-30mm, the cross-sectional dimensions of standard parts 14#~25# hot-rolled ordinary I-beams are optimized and improved, which can reduce the meter weight of lightweight chemical steel, thereby saving steel consumption and steel costs. At the same time, the increase in civil engineering costs can be reasonably controlled, so that the comprehensive cost of lightweight chemical steel arches can be reduced by more than 6%.

[0119] Specifically, the cross-sectional dimensions of standard 14#~25# hot-rolled common I-beams are optimized and improved by "double increase and double reduction" to obtain lightweight chemical steel. The difference Δh between the height of lightweight chemical steel and the standard part takes a maximum value of 30mm in the range of 0~30mm, and the difference Δb between the width of lightweight chemical steel and the standard part takes a maximum value of 30mm in the range of 0~30mm, which can reduce the meter weight of lightweight chemical steel, save steel costs, and reasonably control the increase in civil engineering costs, so that the maximum comprehensive cost of lightweight chemical steel arch frame is reduced by more than 6%. If the difference Δh between the height of lightweight chemical steel and the standard part and the difference Δb between the width of lightweight chemical steel and the standard part are reduced, the comprehensive cost reduction ratio of lightweight chemical steel arch frame will also be reduced accordingly.

[0120] Experimental Example 5

[0121] According to the national standard "GB / T 706-2016 Hot-rolled Steel Sections", the hot-rolled ordinary I-beams with models 14#, 20a#, and 25a# were selected as the basis, and the "double increase and double reduction" optimization and improvement method was adopted to optimize and improve their cross-sectional dimensions respectively, with the height increment being 0 to 35mm and the width increment being 0 to 30mm.

[0122]

[0123] The experimental data in Table 5 show that by adopting the optimization and improvement method of "double increase and double reduction", on the premise that the difference Δh between the height of lightweight chemical steel and the standard part is maintained at 0-35mm, and the difference Δb between the width of lightweight chemical steel and the standard part is maintained at 0-30mm, the cross-sectional dimensions of standard parts 14#~25# hot-rolled ordinary I-beams are optimized and improved, which can reduce the meter weight of lightweight chemical steel, thereby saving steel consumption and steel costs. At the same time, the increase in civil engineering costs can be reasonably controlled, so that the comprehensive cost of lightweight chemical steel arches can be reduced by more than 7%.

[0124] Specifically, the cross-sectional dimensions of the standard 14#~25# hot-rolled ordinary I-beams are optimized and improved by "double increase and double reduction" to obtain lightweight chemical steel. The difference Δh between the height of the lightweight chemical steel and the standard part takes a maximum value of 35mm in the range of 0~35mm, and the difference Δb between the width of the lightweight chemical steel and the standard part takes a maximum value of 30mm in the range of 0~30mm, which can reduce the meter weight of the lightweight chemical steel, save steel costs, and reasonably control the increase in civil engineering costs, so that the maximum comprehensive cost of the lightweight chemical steel arch frame is reduced by more than 7%. If the difference Δh between the height of the lightweight chemical steel and the standard part and the difference Δb between the width of the lightweight chemical steel and the standard part are reduced, the comprehensive cost reduction ratio of the lightweight chemical steel arch frame will also be reduced accordingly.

[0125] Experimental Example 6

[0126] According to the national standard "GB / T 706-2016 Hot-rolled Steel Sections", the hot-rolled ordinary I-beams with models 14#, 20a#, and 25a# were selected as the basis, and the "double increase and double reduction" optimization and improvement method was adopted to optimize and improve their cross-sectional dimensions respectively, with the height increment being 0 to 40mm and the width increment being 0 to 30mm.

[0127]

[0128] The experimental data in Table 6 show that by adopting the optimization and improvement method of "double increase and double reduction", on the premise that the difference Δh between the height of lightweight chemical steel and the standard part is kept at 0-40mm, and the difference Δb between the width of lightweight chemical steel and the standard part is kept at 0-30mm, the cross-sectional dimensions of standard parts 14#~25# hot-rolled ordinary I-beams are optimized and improved, which can reduce the meter weight of lightweight chemical steel, thereby saving steel consumption and steel costs. At the same time, the increase in civil engineering costs can be reasonably controlled, so that the comprehensive cost of lightweight chemical steel arches can be reduced by more than 8%.

[0129] Specifically, the cross-sectional dimensions of standard 14#~25# hot-rolled common I-beams are optimized and improved by "double increase and double reduction" to obtain lightweight chemical steel. The difference Δh between the height of lightweight chemical steel and the standard part takes a maximum value of 40mm in the range of 0~40mm, and the difference Δb between the width of lightweight chemical steel and the standard part takes a maximum value of 30mm in the range of 0~30mm, which can reduce the meter weight of lightweight chemical steel, save steel costs, and reasonably control the increase in civil engineering costs, so that the maximum comprehensive cost of lightweight chemical steel arch frame is reduced by more than 8%. If the difference Δh between the height of lightweight chemical steel and the standard part and the difference Δb between the width of lightweight chemical steel and the standard part are reduced, the comprehensive cost reduction ratio of lightweight chemical steel arch frame will also be reduced accordingly.

[0130] Combined with the experimental data of Experimental Examples 4 to 6, it can be seen that when the difference Δb between the width of the lightweight chemical steel and the standard parts remains unchanged (specifically 30 mm), the greater the difference Δh between the height of the lightweight chemical steel and the standard parts in the range of 0 to 40 m, the greater the comprehensive cost reduction ratio of the lightweight chemical steel arch frame; conversely, the smaller the difference Δh between the height of the lightweight chemical steel and the standard parts in the range of 0 to 40 m, the smaller the comprehensive cost reduction ratio of the lightweight chemical steel arch frame.

[0131] The present application also discloses a method for designing the cross-sectional dimensions of a lightweight chemical steel, which is used to design the cross-sectional dimensions of the above-mentioned lightweight chemical steel. The method is specifically described by taking the experimental group 9 in the above-mentioned experimental example 1 as an example, and comprises the following steps:

[0132] Step 1. Determine the height h of the lightweight chemical steel: first determine the difference Δh between the height of the lightweight chemical steel and the standard part based on 0≤Δh≤40mm, then add Δh to the height h0 of the standard part to obtain the height h of the lightweight chemical steel, that is, the height h of the lightweight chemical steel = Δh + h0.

[0133] Specifically, according to 0≤Δh≤40mm, the difference between the height of the lightweight chemical steel beam and the standard part is determined to be Δh=40mm, the height of the standard part 14# hot-rolled ordinary I-beam h0=140mm, and the difference Δh between the height of the lightweight chemical steel beam and the standard part is added to the height h0 of the standard part to obtain the height of the lightweight chemical steel beam h=Δh+h0=40+140=180mm.

[0134] Step 2: Determine the minimum value d of the web thickness min :According to the minimum value of web thickness d min =1.6872ln(h)-4.5772, substitute the height h of the lightweight chemical steel into the calculation to obtain the minimum value d of the web thickness min .

[0135] Specifically, according to the minimum value of the web thickness d min =1.6872ln(h)-4.5772, substitute the height of the lightweight chemical steel h=180mm into the calculation, and get the minimum value of the web thickness d min =1.6872ln(180)﹣4.5772=4.18mm.

[0136] Step 3: Determine the thickness d of the web: According to the thickness of the web d min ≤d≤1.8d min , determine the thickness d of the web.

[0137] Specifically, the value range of the web thickness d is d min ≤d≤1.8dmin , determine the thickness of the web to be d = 4.3 mm.

[0138] Step 4: Determine the thickness t of the wing plate: According to the relationship between the thickness t of the wing plate and the thickness d of the web plate, d≤t≤2d, determine the thickness t of the wing plate.

[0139] Specifically, according to the relationship between the thickness t of the wing plate and the thickness d of the web plate, d≤t≤2d, the thickness of the wing plate is determined to be t=4.3 mm.

[0140] Step 5: Determine the width b of the lightweight chemical steel: According to the strong axis section modulus W of the lightweight chemical steel x Compared with the standard parts, the variation is kept within the range of ±10%. First, the strong axis section modulus W of the lightweight chemical steel is determined. x Then determine the slope of the wing plate within the range of 2% to 16.7%, determine the arc radius r at the connection between the wing plate and the web within the range of 7.5 to 10.0 mm, determine the arc radius r1 at the end of the wing plate within the range of 2.0 to 5.0 mm, and then according to the formula W x =2∫y 2 dA / h, substitute the height h of the lightweight chemical steel, the thickness d of the web, the thickness t of the wing plate, and the strong axis section modulus W of the lightweight chemical steel x , the slope of the wing plate, the arc radius r at the connection between the wing plate and the web, and the arc radius r1 at the end of the wing plate are calculated to obtain the width b of the lightweight chemical steel.

[0141] Specifically, according to the strong axis section modulus W of lightweight chemical steel x Compared with the standard parts, the variation is kept within the range of ±10%. First, the strong axis section modulus W of the lightweight chemical steel is determined. x Compared with the standard part, the change is 2.0%, so the strong axis section modulus W of the lightweight chemical steel is x =104cm 3 Then, the slope of the wing is determined to be 2% within the range of 2% to 16.7%, the arc radius r = 7.5mm at the connection between the wing and the web is determined to be within the range of 7.5 to 10.0mm, and the arc radius r1 = 2.0mm at the end of the wing is determined to be within the range of 2.0 to 5.0mm. Then, according to the formula W x =2∫y 2 dA / h, substitute the height h of the lightweight chemical steel, the thickness d of the web, the thickness t of the wing plate, and the strong axis section modulus W of the lightweight chemical steel x , the slope of the wing plate, the arc radius r at the connection between the wing plate and the web, and the arc radius r1 at the end of the wing plate are calculated to obtain the width b of the lightweight chemical steel beam = 110 mm.

[0142] Step 6. Verify the difference Δb between the width of the lightweight chemical steel and the standard part: subtract the width b0 of the standard part from the width b of the lightweight chemical steel calculated in step 5 to obtain the difference Δb between the width of the lightweight chemical steel and the standard part, that is, the difference Δb between the width of the lightweight chemical steel and the standard part = b-b0. If the calculated Δb does not meet 0≤Δb≤30mm, redetermine the height h of the lightweight chemical steel, the thickness d of the web, the thickness t of the wing plate, and the width b of the lightweight chemical steel according to steps 1 to 5, and then recalculate Δb until the calculated Δb meets 0≤Δb≤30mm.

[0143] Specifically, the wing plate width b0 of the standard 14# hot-rolled ordinary I-beam is 80 mm. The width b of the lightweight I-beam calculated in step 5 is subtracted from the width b0 of the standard part to obtain the difference between the width of the lightweight I-beam and the standard part Δb=b-b0=110-80=30 mm. The calculated Δb meets the condition of 0≤Δb≤30 mm.

[0144] The present application also discloses a production roller for lightweight chemical steel, which is used to produce the above-mentioned lightweight chemical steel, and its shape and size match the shape and size of the lightweight chemical steel.

[0145] Example 2

[0146] In this embodiment, based on the cross-sectional dimensions of large-size hot-rolled ordinary I-beams, the height h and / or width b of the hot-rolled ordinary I-beams are reduced, and the thickness d of the web and / or the thickness t of the wing are reduced, so as to obtain a lightweight I-beam similar to that of embodiment 1 to replace the small-size hot-rolled ordinary I-beams. For example, based on the cross-sectional dimensions of 16# hot-rolled ordinary I-beams, the height h and / or width b of the hot-rolled ordinary I-beams are reduced, and the thickness d of the web and / or the thickness t of the wing are reduced, so as to obtain a lightweight I-beam similar to that of embodiment 1 to replace the 14# hot-rolled ordinary I-beams.

[0147] Although the improvement methods of this embodiment are different from those of embodiment 1, the improvement results obtained are the same, and the model of the hot-rolled ordinary I-beams replaced is also the same, so the effects that can be achieved are also the same.

[0148] The above is only an embodiment of the utility model, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the technical solution of the utility model, which should also be regarded as the protection scope of the utility model, and these will not affect the effect of the implementation of the utility model and the practicality of the patent. The scope of protection required by this application is not limited to the use environment of the tunnel engineering described in the embodiment, but should be based on the content of its claims. The specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A lightweight steel beam, comprising two wing plates with upper and lower surfaces arranged parallel to each other, and a web plate vertically connected to the middle of the two wing plates; characterized in that: The height and / or width of the lightweight chemical steel beam is greater than the standard part it replaces, and the thickness of the web and / or wing plate is less than the standard part it replaces. The strong axis section modulus W of the lightweight chemical steel beam x The variation compared to the standard part is kept within ±10%, and the cross-sectional area is reduced compared to the standard part.

2. A lightweight chemical steel beam according to claim 1, characterized in that: The height difference between the lightweight chemical steel and the standard part is 0≤Δh≤40mm, and the width difference between the lightweight chemical steel and the standard part is 0≤Δb≤30mm.

3. A lightweight chemical steel beam according to claim 2, characterized in that: The height difference between the lightweight chemical steel and the standard part is 0≤Δh≤35mm.

4. A lightweight chemical steel beam according to claim 3, characterized in that: The height difference between the lightweight chemical steel and the standard part is 0≤Δh≤30mm.

5. A lightweight chemical steel beam according to any one of claims 2 to 4, characterized in that: The height and width of the lightweight cross-section steel are both greater than the replaced standard parts, and the thickness of the web plate and the wing plate are both less than the replaced standard parts.

6. The lightweight chemical steel beam according to claim 1, characterized in that: The thickness of the web has a minimum value d min , and the minimum value d min Related to the height h of lightweight chemical steel, d min =1.6872ln(h)﹣4.5772.

7. A lightweight chemical steel beam according to claim 6, characterized in that: The thickness of the web is d min ≤d≤1.8d min , the thickness of the wing plate is d≤t≤2d, the slope of the wing plate is 2% to 16.7%, and the slope of the wing plate is positively correlated with the thickness of the wing plate.

8. A production roll for lightweight chemical steel, characterized in that: Used to produce a lightweight chemical steel beam as described in any one of claims 1 to 7, its shape and size match the shape and size of the lightweight chemical steel beam.

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