Project Description

Nanjing Metro is a 617 km long metro that consists of 17 lines, located in eastern China, Jiangsu Province. Its construction period will continue for the next 30 years. By June, 2010, 80 km metro line has been opened for operation. Stable metro segment demand will last for another 19 years before its completion in year 2030.

Project Requirements

The precast segment production requires high strength concrete in combination with smooth and uniform surface finish. Due to a constant tunnel construction progress of 30 km per year it is necessary to produce 500 concrete tunnel segments per day. This results in challenging requirements regarding early strength development of the concrete by which a rapid formwork turnaround can be realized. Normally, setting times must be controlled within 100 minutes and early compressive strength development over 20 MPa has to be ensured for a three-shift operation.

Sika Solutions

The use of Sika® ViscoCrete®-20 HE provided the solution for the challenging requirements. The high early strength gained by using Sika® ViscoCrete®-20 HE has shortened the striking time and hence accelerated the turnaround of formwork, in addition steam curing time and energy consumption can be reduced. The overall result for the segment manufacturer is an increased production rate with significantly improved product quality.

Besides, Sika could gain high reputation by providing value-added technical and logistic service.

Sika Products

In addition the following Sika product was used in the project

  • Sika® ViscoCrete® -20 HE Superplasticizer

Project Participants

Owner: Nanjing Metro Group
Contractor: China Railway Construction Group
China Communications Construction Group
Engineer: Beijing Urban Engineering Design & Research Institute Co.,Ltd
China Railway No 4 Survey and Design Institute Co.,Ltd