News Information

On May 24, 2024, the Ministry of Housing and Urban-Rural Development issued a partially revised version of the "Seismic Design Code for Buildings" (GB50011-2010) and the "Code for Design of Concrete Structures" (GB50010-2010). According to the report, the standard names and numbers are "Seismic Design Standard for Buildings" GB/T50011-2010 and "Design Standard for Concrete Structures" GB/T50010-2010, and will be officially implemented on August 1, 2024.

In recent years, the construction industry has shifted from rapid development to high-quality development. Based on the national policy of promoting energy conservation, emission reduction, and high-quality development of the industry, the Ministry of Housing and Urban-Rural Development proposed to revise the "Design Standards for Concrete Structures" in order to further promote high-strength steel bars, high-strength and high-quality Provide technical support for performance concrete engineering applications. The "Concrete Structure Design Standards" were officially released on April 24, 2024, with a total of 26 articles revised. The main revisions and changes are as follows:

1. Modified the minimum requirements for concrete strength grade

In response to Article 2.0.2 of the General Specifications for Concrete Structures, the Concrete Structure Design Standard has simultaneously coordinated the requirements for concrete strength grade and appropriately increased the minimum strength grade requirements. At the same time, it should be noted that plain concrete cushions are generally not used as structural components. For specific requirements, please refer to the relevant standards for foundations.

2. Delete the relevant provisions on HRB335 steel bars

Articles 4.2.1, 4.2.2, 4.2.3, 4.2.4, 4.2.5, and 4.2.6 (a total of 6 articles) of the Concrete Structure Design Standard GB/T 50010 have deleted the relevant provisions on HRB335 steel bars. The original specification for the mechanical performance indicators of HRB335 steel bars can still be used for reference. At the same time, Articles 4.2.2, 4.2.3, and 4.2.5 of the "Concrete Structure Design Standard" GB/T 50010 do not complete the strength index regulations of seismic steel bars such as HRB400E; they can be adopted according to the corresponding steel bars without E.

3. Modification of individual errors (inconsistent) content and inaccurate textual expressions

The modifications of this article are mainly to modify some contents in the original specification that are inconsistent with the general specification, as well as some typos and inaccurate textual expressions. For example: in Article 8.5.3, the M in the formula description is modified. Here it should be the design value of the section bending moment, not the design value of the section bearing capacity, and it must meet the crack resistance requirements of concrete components at the same time.

4. Coordinated modifications with the main contents of the "General Code for Concrete Structures" GB 55008-2021 

1) Article 9.1.2, paragraph 2: The thickness of cast-in-place reinforced concrete slabs is uniformly increased to 80mm, the solid roof panel is increased by 100mm, and the thickness requirements of the root of the cantilever slab are tightened.

2) Article 9.4.5: "Should" was changed to "shall", and the reinforcement ratio of horizontal and vertical distributed steel bars should not be less than 0.15%.

3) Article 9.5.2, paragraph 2: The thickness of the post-cast superimposed layer of the superimposed slab was modified (40 to 50); the concrete strength grade was deleted.

4) The provisions of the prestressed action combination coefficient were modified, and the provisions of Article 3.1.13 of the General Code for Engineering Structures GB 55001-2021 were directly quoted: When the prestressed action is unfavorable, the partial coefficient has two provisions of 1.3 and 1.2 (for building structures and highway bridge and culvert structures).

5) Article 11.2.1, paragraph 2, modified the concrete strength grade.