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Regarding the re verification of prefabricated panel components, Qingdao Urban Planning and Design Institute’s Qi Fengbo New Design Project and Appraisal Reinforcement Project often involves prefabricated components.
Even if the atlas based on it is in hand, is it necessary to further analyze it? The following will conduct research on it.
Possible situations for new design projects: standards and specifications involve revision in the implementation process, but the specifications used in the latest prefabricated member atlas may be the old version that has just been updated.
For example, the design of a project adopts the improved load partial coefficient according to the latest standards and specifications, but the partial coefficient of the old version of the specifications on which the latest prefabricated member atlas is based has not been improved, It is definitely not appropriate to directly use this atlas to select components, which involves the conversion of components or design intervention in the production of prefabricated components, in order to ensure that the prefabricated components used in this project meet the latest specifications and ensure the uniformity of the reliability level of the entire project.
To give an example that is not very appropriate, a cold storage will be designed in 2022, and all standard specifications will be based on the latest version.
The roof will be made of prestressed concrete double T slabs.
The “Prestressed Concrete Double T Slabs” (18G432-1) is a collection of drawings issued in 2018, and the “Unified Standard for Reliability Design of Building Structures” (GB50068-2018) will be implemented from April 1, 2019.
There were concerns in this regard at the beginning, but after carefully reading the collection, Thanks to its foresight in adjusting the partial factors to 1.3 and 1.5 in advance, this problem can be avoided.
The roof dead load is generally larger than the floor dead load, so it is also necessary to check the prefabricated components, and take measures to limit the load, select components according to a larger span, or directly adjust the design and customized production to ensure safety.
The situation that may be encountered in the appraisal and reinforcement project: The appraisal of existing buildings should be carried out simultaneously with safety appraisal and seismic appraisal.
Regarding the requirements for seismic appraisal, for buildings with a subsequent service life of 30 years (Class A buildings), it usually refers to buildings designed and constructed before the formal implementation of the Design Specification for Seismic Design of Buildings GBJ11-1989, The appraisal requirements basically adhere to the relevant provisions of the “Building Seismic Appraisal Standard” GB50223-1995 for buildings designed and constructed during this period, that is, under the premise of unchanged functions, historical buildings can meet historical specifications
.
