Controlled Low-Strength Materials (CLSM) as backfill: experimental investigation on CLSM properties and numerical evaluation of stresses and strains using PLAXIS 2D

ABSTRACT

Retaining walls are a part of the geotechnical construction industry for the support of structures from soil erosion. Granular materials are conventionally used as backfill behind retaining walls. Instead of the conventional compacted granular fill, other industrial by-products are also used nowadays. The utilisation of these industrial by-products for Civil engineering applications helps to build a sustainable environment by reducing the waste depositions. In this paper, an experimental study was conducted to evaluate the properties of coal ash-based Controlled Low Strength Materials (CLSM) for backfill applications. The properties of pond ash-based CLSM mixes were studied to identify the effectiveness in utilising CLSM for backfill applications. Further, numerical analysis using PLAXIS 2D was carried out to evaluate the stresses and displacements developed in retaining walls for different backfilling materials. It was observed that CLSM mixes exhibit the properties required for utilising it as a backfill material. The stresses and deformations developed in situations where CLSM was used were found to be negligible compared to the normal compacted backfill materials. Thus, the studies on CLSM mixes showed that pond ash can be used as a replacement to natural aggregates which can be used as a backfill for retaining wall applications.

KEYWORDS:

• Back fills
• CLSM
• elastic modulus
• flowable fills
• pond ash
• retaining walls
• shear strength

Acknowledgements

The authors would like to acknowledge the support given by Dr. R.G. Robinson, Professor, Department of Civil Engineering, IIT Madras. The authors would also like to thank CSIR- CECRI, Karaikudi, Tamil Nadu, India for providing the X- Ray Fluorescence studies on pond ash.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Ethical Standards

The authors hereby states that the experiments comply with the current laws of our country.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.