English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

This paper discusses two alternative solutions to remedy the difficulties and challenges associated with low-cost field methods for construction of concrete biosand water filter housings. Outer and inner forms are required to retain the concrete in the desired shape for the filter housing. Removal of the inner form can be a challenging process. The first method outlines a procedure for the use of an inflatable boat fender that is used for the inner form. The boat fender can be deflated and easily removed after the concrete is set. The second method uses stuffed feed sacks for the inner form. The feed sacks are stuffed with a granular material and stacked vertically. After the concrete is set, the granular material is removed and the feed sacks are readily separated from the concrete. Both methods of construction are described in detail. Findings include two rapid field methods for constructing inexpensive concrete biosand water filter housings.

Improved Field Methods for Construction of Concrete Biosand Water Filter Housings