event

PhD Defense by Yue Xu

Primary tabs

Ph.D. Thesis Defense Announcement

Puncture Resistance of Turf Reinforcement Mats

 

by

Yue Xu

 

Advisor(s):

Dr. J. David Frost (CEE), Dr. Susan E. Burns (CEE)

Committee  Members:

Dr. Arun M. Gokhale (MSE), Dr. Mahdi Roozbahani (CSE), Dr. Glenn J. Rix (Geosyntec Consultants)

 

 

 

Date & Time:  

Tuesday, January 12th, 2020 at 9:00 a.m.

 

Location:   https://bluejeans.com/564265773

ABSTRACT

Turf reinforcement mats are used as a non-degradable erosion control material to provide long-term slope or channel protection before and during vegetation establishment. While most manufacturers are interested in emphasizing the service life of their products, the question of mechanical damage during and after installation is always a key issue that has rarely been addressed in previous studies. Puncturing is one of the main mechanical damage issues that happens quite often during the lifetime of turf reinforcement mats.

The thesis focuses on the analysis of puncture resistance as well as other physical and mechanical properties of turf reinforcement mats. This work seeks to identify the correlation between index properties and their mechanical properties, which can help engineers identify suitable materials during product selection. The experimental results show that the static puncture resistance and extensibility of woven turf reinforcement mats increase as mass per unit area increases. This study also investigates the puncture resistance of soil-turf reinforcement mat systems by performing California-Bearing-Ratio-based puncture tests. Experimental results show that turf reinforcement mat can remarkably improve the penetration value of soil-turf reinforcement mat system by up to almost 60% compared to the soil only system. It is also observed that soil benefits more in penetration tests with higher puncture resistance and mass per unit area of the turf reinforcement mat.

The numerical simulation of the puncture test of turf reinforcement mats illustrates their damage characteristics with the change of projectile shape, material density, and material geometry. The results indicate that turf reinforcement with greater density has a higher puncture resistance which reflects a similar trend seen in experimental tests. Also, the modeling results show that a turf reinforcement mat impacted by a projectile with a flat tip presents the greatest puncture resistance compared with those punctured by the projectiles of conical and hemispherical tips. The simulation of the soil-turf reinforcement mat system shows higher soil reinforcement at shallow soil depths.

In engineering practice, turf reinforcement mats are usually applied for soil erosion control together with vegetation reinforcement. A series of experiments were also performed to explore the reinforcement of the plant roots-turf reinforcement mat system, especially for young plants. In this study, Dandelion and Ryegrass were selected as representative of vegetation with taproots and fibrous roots. The experimental results suggest that the pullout resistance of fibrous roots is greater than that of taproots. Although the application of turf reinforcement mat does not have a clear effect on the pullout resistance of plant roots, it improves their initial pullout modulus. In addition, turf reinforcement mat coverage over soil can reduce water evaporation up to 78% thereby retaining soil moisture during seed germination.

Status

  • Workflow Status:Published
  • Created By:Tatianna Richardson
  • Created:12/30/2020
  • Modified By:Tatianna Richardson
  • Modified:12/30/2020

Categories

Keywords