FOR Tunnel Liner Rings

Tunnel Lining with Segmental Rings

This paper presents a practical approach to the study of defects in a tunnel-boring machine (TBM) ring due to the lack of gap filling during the construction phases. This lack of gap fill can produce an uncontrolled ovalization of the ring, which can lead to multicracking along the segments, in particular at the tunnel crown. After a brief description of the causes of the problem and the state of the art of ovalization in a Tunnel Ring, a real case is analyzed considering the nonlinear moment curvature behavior of a reinforced concrete section based on the constitutive laws of the materials leading to a redistribution of internal forces. The results of this approach are compared with measured field data, in particular regarding the tunnel ovalization and the crack widths detected along the ring.

Product feature:

* It is widely be used in concrete construction of various underground projects.
* The product is easy to use and flexible to disassemble.
* More times turnover, low cost amortization.
* The appearance of concrete is well quality.
* Save labor cost and reduce project cost.

Advantage:

● light weight; 
● simple, strong and stable structure; 
● moved, mounted and stripped easily; 
● strong reusability; 
● small deformation under force; 
● adequate space under traveler and providing a big space for bars and formwork construction operation.

Lijian Formwork is a professional manufacturing enterprise specializing in construction formwork, steel structure and mechanical equipment. It can provide construction enterprises with a series of high-quality services such as formwork and steel structure engineering technical consultation, scheme design, processing and production, sales, leasing and on-site technical guidance and installation.
The company is affiliated to Beijing Lijian Engineering Technology Co., Ltd., Shandong Lijian Formwork Co., Ltd., and Anshan Lijian Engineering Co., Ltd. The company's processing bases are located in Tai'an City, Shandong Province and Anshan City, Liaoning Province. Relying on advanced technology and strong processing strength, the company's business has developed rapidly. Since its establishment, the company has participated in hundreds of major domestic projects. The company's product system is widely used in infrastructure construction fields such as high-speed railways, subways, water conservancy, expressways, underground pipe corridors, and municipal engineering. It has the characteristics of reasonable structure, convenient operation, reliable quality and high cost performance. It has established a good cooperative relationship with China Railway, China Railway Construction, China State Construction, China Hydropower, China Communications Construction, China Power Construction and other construction companies.

The company's business has expanded to 15 provinces, cities and autonomous regions across the country, and exported to the United States, the United Arab Emirates, Cambodia and other countries. At the beginning of its establishment, the company took quality and technology as the foundation of the company, and took the lead in obtaining quality certification and applying for a number of national patents. Product quality stability and technological advancement are at the forefront of the industry.
The company takes "credibility first, users first" as its corporate purpose, "quality for survival, innovation for development" as its business philosophy, and wins the trust of construction units with innovative technology and high-quality services to create good economic and social benefits for them.

Value-added services:
Provide construction plan for civil engineering and cooperate with Bidding for Party A.
Provide early product design and the most cost-effective scheme.
After sales service and technical support during construction.
Free product improvement scheme.