T/CI 052-2023 Active

Scope: This document specifies the terms and definitions, construction, classification, marking, raw materials, technical requirements, testing methods, inspection rules, storage and in-plant transportation, and product quality certificates for precast concrete columns and cap beams used in highway and municipal bridge structures. This document applies to precast concrete columns and cap beams used in highway and municipal bridge structures. Main technical content: 5. Raw materials 5.1 Column concrete a) Cement shall comply with the provisions of GB 175-2007, and silicate cement is recommended. b) Fine aggregates may be natural sand or manufactured sand. It is recommended to use well-graded river sand with a fineness modulus of 2.3 to 3.0 and a clay content not exceeding 1.0%. For highway projects, other technical indicators shall comply with the provisions of Table 6.3.1 of JTG/T 3650-2020; for urban bridge projects, other technical indicators shall comply with the relevant provisions of JGJ 52-2006. c) Coarse aggregates shall be hard and well-graded crushed stones or pebbles with a maximum diameter not exceeding 50 mm and a clay content not exceeding 0.5%. For highway projects, other technical indicators shall comply with the provisions of Table 6.4.1 of JTG/T 3650-2020; for urban bridge projects, other technical indicators shall comply with the relevant provisions of JGJ 52-2006. d) Fly ash shall comply with the provisions of GB/T 1596-2017, and grade II or higher fly ash shall be used. e) Admixtures shall comply with the relevant provisions of GB 8076-2008. f) For concrete mixing water used in reinforced concrete, the pH value of the water shall not be less than 4.5; the chloride content in the water shall not exceed 1000 mg/L; and other indicators shall comply with the provisions of JGJ 63-2006. g) Granulated blast furnace slag powder shall comply with the provisions of GB/T 18046-2017. Steel materials: a) Hot-rolled round steel bars and