A financial center in Beijing (large volume concrete)

(1) Project Overview: The building has 101 floors above ground and 3 floors underground, with a solid height of 492m above ground; The total construction area is 377300 square meters.

(2) Technical requirements: The concrete should have good workability, workability retention ability, no bleeding, no segregation, and a certain degree of thixotropy.

(3) Engineering difficulties:

1) The total amount of concrete is about 300000 cubic meters, including 35374 cubic meters of concrete for the main base plate.

; Pouring in three stages, the amount of concrete poured in one stage for Z is 27749m3/44; Thickness 4.5m; Strength grade is C40&# 44; The pumping distance exceeds 300m.

2) Due to the large volume of one-time pouring, high thickness of the bottom plate, control of the heat release rate of concrete, maintenance of workability, uniformity, and compactness are particularly important. After multiple experimental screenings, the construction unit has decided to use our polycarboxylate superplasticizer.

(4) Engineering Practice: The main floor concrete of this project is 35374m3&# 44; Pouring in three stages, with the amount of pouring after Z being 27749m3/44; A total of 8 mixing plants participated in the ash supply, using 350 tank trucks, 18 fixed pumps, and 1 mobile pump to continuously pour for 40 hours. Although there are 8 mixing plants involved in supplying ash, the concrete has good uniformity and is very easy to pump and vibrate.