A review of recycled aggregate in concrete applications (2000–2017)

There are number of water purification techniques but the adsorption is one of the most simplest, effective and economical method for wastewater purification. In this article a large number of solid adsorbents such as Natural adsorbents, Agricultural Wastes, Industrial wastes, Biomass, Nanoadsorbents: Carbon based nanomaterials, Nobel metal based nanomaterials, Metal oxide based nanomaterials, Spinel ferrite based nanomaterials, Nanocomposites, Dendritic polymers; Geopolymer cement have been discussed for the removal of different pollutants from waste water. Removal of Fluoride, Phosphate, Nitrate and Radionuclides from wastewater has also been reviewed in this article. Adsorption isotherm models, kinetic models, thermodynamic parameters and adsorption mechanism have also been discussed. The present article lists different type of adsorbents and reviews state-of-the-art of the removal of different pollutants from water. The efforts have been made to discuss the sources of contamination and toxicities of pollutants. Adsorption mechanisms responsible for pollutants removal by different adsorbents have been reviewed. Attempts have also been made to point out the advantages and drawbacks of adsorbents and the future research needs in the area of water purification by adsorbents.

Water purification by using Adsorbents: A Review

Construction and demolition waste generation and properties of recycled aggregate concrete: A global perspective

A comprehensive laboratory evaluation of the geotechnical and geoenvironmental properties of five predominant types of construction and demolition (C&D) waste materials was undertaken in th...

https://researchbank.swinburne.edu.au/file/9bbb0fa6-5557-4c65-ada9-7a360c041032/1/PDF (Accepted manuscript).pdf

Geotechnical and geoenvironmental properties of recycled construction and demolition materials in pavement subbase applications

A review of waste products utilized as supplements to Portland cement in concrete

This paper discusses the geological and hydrogeological features of Quaternary deposits in Tianjin as well as the geohazards related to groundwater hydrology in this region. The soft soil deposits, comprising silt, sand, silty clay and clay, are composed of four aquifer groups. In the first aquifer group, one phreatic aquifer and two confined aquifers have relationships with underground construction in the urban area. These three aquifers are separated by two aquitards and collectively form a multi-aquifer system. During geotechnical construction, potential geohazards present are related to the groundwater, which include water-in-rushing, quicksand and piping hazards. To prevent the aforementioned geohazards, dewatering is conducted; however, groundwater pumping may result in large settlements of the surrounding ground. To reduce pumping-induced settlement, the dewatering–waterproofing system has been adopted. According to the characteristics of the subsoil, excavation depth and the surrounding environment, the dewatering system can be divided into five patterns. In the first four patterns, when pumping is conducted in the excavation pit, the groundwater head in the adjacent aquifers outside the pit decreases due to the leakage effect of the aquitards located between the aquifers. In the fifth pattern, waterproof curtain has cut off the aquifers completely and dewatering in the pit cannot result in settlement around excavation pit. To avoid geohazards related to groundwater hydrology, countermeasures recommended include construction of an effective waterproof curtain, selection of a reasonable excavation dewatering pattern and withdrawal of required groundwater.

Geological and hydrogeological environment in Tianjin with potential geohazards and groundwater control during excavation

The Changi East reclamation project was carried out in five phases along the foreshore of the east coast of Singapore. The water depths in the reclaimed area ranged from 5 to 15 m. The project involved hydraulic placement of 272 million m3 of sand onto soft seabed marine clay up to 50 m thick. A linear total of 170,000 km of prefabricated vertical drains (PVDs) were installed for accelerating the consolidation process of the underlying soft marine clay. The soil improvement works covered a total area of approximately 1200 ha. In this paper, the site conditions and the soil improvement works adopted are described. Pilot tests with full-scale field instrumentations as well as laboratory and in situ tests were carried out to verify the design, check the effectiveness of the soil improvement works using PVDs, and establish the most suitable drain spacing. Field monitoring data obtained from both the pilot tests and the reclamation works are presented and interpreted. Degree of consolidation was calculated bas...

Soil improvement works for an offshore land reclamation

Influence of class F fly ash and curing temperature on strength development of fly ash-recycled concrete aggregate blends

Construction and demolition materials account for a major proportion of the waste materials present in landfills in Australia. Crushed brick and crushed rock are, however, viable substitute materials for natural resources used as construction materials in engineering applications. Crushed brick is one of the major components of demolition materials. The crushed rock used in this study originates from ‘basalt floaters’ or surface excavation rock (basalt), which commonly occurs near the surface to the north and west of Melbourne, Australia. The engineering characteristics of various proportions of crushed brick blends with crushed rock obtained from extensive laboratory testing are presented in this paper. The engineering properties obtained were compared with existing local road authority specifications for pavement sub-base or light-duty base material and backfill material for drainage systems to ascertain the potential use of crushed brick blends. The materials for the experimental works were collected f...

https://researchbank.swinburne.edu.au/file/6974471f-c2a6-4179-bcce-7a39c175b508/1/PDF (Published version).pdf

Crushed brick blends with crushed rock for pavement systems

The Changi East Reclamation Project in Singapore comprises land reclamation in foreshore conditions. As the foreshore area was underlain by a thick layer of soft marine clay, a high magnitude of primary and secondary consolidation settlement was expected, owing to fill and future live load. An average fill thickness of 10 m was predicted to contribute to a magnitude of settlement greater than 2 m over a period of several decades. In order to minimise this expected future settlement, it was necessary to accelerate the consolidation process to complete the majority of the settlement during construction stage. A combination of prefabricated vertical drains (PVDs) with preloading ground improvement was successfully applied in this project. The technique comprises the installation of prefabricated vertical drains and the subsequent placement of surcharge to accelerate the consolidation of the underlying marine clay. This paper discusses the theories of radial drainage and the preloading technique, and consider...

https://researchbank.swinburne.edu.au/file/e8c224c3-708a-4982-be63-6952c3af0641/1/PDF (Published version).pdf

Arul Arulrajah

Papers

Geological and hydrogeological environment in Tianjin with potential geohazards and groundwater control during excavation

Soil improvement works for an offshore land reclamation

Influence of class F fly ash and curing temperature on strength development of fly ash-recycled concrete aggregate blends

Crushed brick blends with crushed rock for pavement systems

Preloading and prefabricated vertical drains design for foreshore land reclamation projects: a case study