On September 8, 2024, the review meeting for the China Association for Engineering Construction Standardization (CECS) standard "Technical Specification for Integration of Underground Structures and Foundation Pit Support Structures" (draft for review) (hereinafter referred to as the "Specification"), chief-edited by Shandong University, was held in Beijing. Director Tang Yajun of the Technical Standards Department of CECS, review experts, and members of the drafting group attended the meeting. The meeting was chaired by Researcher Gao Wensheng, Chairman of the Foundation Engineering Professional Committee of CECS.

The meeting formed a review expert group headed by Hua Jianxin, National Engineering Survey and Design Master, with Wang Lijun, National Engineering Survey and Design Master, as deputy head, and members including Researcher Teng Yanjing, Honorary Chairman of the Foundation Engineering Branch of the Architectural Society of China, Professor Song Erxiang of Tsinghua University, Professor-level Senior Engineer Zhang Jinxun of Beijing Urban Construction Group, Professor-level Senior Engineer Han Xuan of Beijing Institute of Survey and Design Co., Ltd., and Professor-level Senior Engineer Yue Ling of China Railway Engineering Design and Consulting Group Co., Ltd.

Professor Li Lianxiang, chief editor of the Specification and Director of the Foundation Pit Engineering Research Center of Shandong University, presented on behalf of the drafting group an introduction to the standard's preparation and explanations of relevant technical content.

The review expert group conducted a clause-by-clause review of the Specification's content and unanimously agreed that it complies with the provisions for drafting engineering construction standards, that the submitted materials are complete and meet review requirements, and that the content is scientific and reasonable, highly operable, and coordinated with existing relevant standards. It provides guidance for the high-quality development of foundation pit engineering, fills relevant technical gaps, and generally reaches the international advanced level. They unanimously agreed that the Specification passes review.

The Specification changes the current "temporary" concept and practice of foundation pit support structures, adopts a method of coordinated design between foundation pit support and the main structure, and directly positions deep foundation pit support pile walls as part of the main structure. This reduces the stiffness of traditional underground structures and saves building materials, overcomes the drawbacks of waste, pollution, and high carbon emissions associated with current temporary foundation pit support pile walls, and establishes an important direction for the high-quality development of foundation pit engineering. Preliminary estimates suggest that application of this technology can save more than 4 million yuan in investment for a current 200 m long subway station, and based on the current scale of urban construction, it is estimated to create direct benefits of more than 10 billion yuan per year.

The Specification is the third high-quality foundation pit engineering technical standard from Shandong University and the foundation for the widespread application of "permanentization" technology for deep foundation pit support structures. Since 2018, the foundation pit engineering research team of Shandong University has proposed a high-quality development direction of "permanentization of deep foundation pit support, full recovery of temporary support for shallow foundation pits, and scientific utilization of foundation pit rock masses," and has successively completed the CECS standard "Technical Specification for Fully Recyclable Foundation Pit Support" T/CECS 1208-2022 and the Shandong Provincial engineering construction technical standard "Technical Standard for Soil-Rock Dual-Element Foundation Pit Support" DB37/T 5233-2022, and published the monographs "Soil-Rock Dual-Element Deep Foundation Pit Engineering" and "Deep Foundation Pit Engineering of Underground Structure Groups." The approval of the draft for review of the "Technical Specification for Integration of Underground Structures and Foundation Pit Support Structures" will accelerate the establishment of a high-quality construction framework for foundation pit engineering in China.

This Specification is jointly chief-edited by Shandong University and Zhongshiye Investment Group Construction Co., Ltd., with support from 30 editorial committee units across 16 provinces and municipalities nationwide, and integrates achievements from domestic foundation pit research teams such as Shanghai Jiao Tong University, Tianjin University, Zhejiang University, and East China Architectural Design & Research Institute Co., Ltd. The meeting required the drafting group to complete the draft for approval of the Specification as soon as possible to facilitate its promulgation and implementation.