At 5 PM on July 2, the last concrete pouring of the No. 4 main pier cap of the G3 Tongling Yangtze River Gongtie Bridge was completed successfully. At this point, the construction of the south main tower cap of the bridge ended and officially entered the tower construction stage。

　 The main pier cap is one of the key control nodes of the bridge. The area of the south main pier cap of the G3 Tongling Yangtze River Railway Bridge is 3373.5 square meters, equivalent to the area of eight standard basketball courts, the concrete cap is 7 meters high。China Railway Bridge Bureau G3 Tongling Yangtze River Railway Bridge project executive deputy manager Mou Xiang introduced，To ensure the quality of concrete，Minimize construction time while ensuring that the concrete curing cycle is met，The project department further optimizes the construction plan，The concrete is placed horizontally in layers and horizontally in blocks，The bearing concrete is prepared according to the technical requirements and technology of mass concrete，The bearing concrete is poured in two layers，Height of each pouring 3.5 meters, each layer is divided into two pours, and 2 meters after pouring section is set in the middle。The concrete was poured and the rebar was tied at the same time, again reflecting a different G3 speed。

　 It is reported that since the first pouring started at 11:40 p.m. on June 7, the builders of the bridge Bureau completed the pouring of the bulk concrete for the main pier bearing in only 24 days。A total of 23614 concrete was poured on No. 4 main pier cap.5 cubic meters, 3,498 rebar consumed.3吨。The successful pouring of No. 4 main pier cap indicates that the main pier on the south bank of the bridge will enter the visual construction stage。

　 China Railway Bridge Bureau G3 Tongling Yangtze River Railway Bridge project management Department, project manager Diao Xinguo said，To ensure the quality of the project，The cap rebar is manufactured by the rebar workshop，Making an "identity card" for steel bars，List the steel bar model, specifications, batch, production date, the corresponding drawing number and other important information，One by one for on-site installation，Improve work efficiency，At the same time, the traceability of problem steel bars is realized，Ensure the quality of reinforcement construction is effectively controlled。Cap formwork adopts composite steel formwork，In the process of pouring to ensure that the concrete mold temperature below 30 degrees，The concrete mixing process，Add ice，Control the temperature of the concrete outlet，And the concrete tank truck is sprayed with water to cool，Ensure that the mold temperature is lower than 30 degrees，The influence of high temperature weather on the quality of concrete is overcome。

　 The circulating cooling water system is set in the cap to reduce its internal temperature, and the top water is stored to retain moisture and reduce the temperature difference between the inside and outside of the cap, which effectively controls the temperature difference between the inside and outside of the concrete during the maintenance period and prevents the occurrence of cracks on the surface of the concrete. The reinforced iron bones of the No. 4 main pier form the "solid inside and beautiful outside" of the large cap.。