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Taiwan is a small island with a large population, where roads are frequently excavated and backfilled due to pipeline burying and maintenance. The old construction way was backfilled by origin soil or road-paving aggregate which caused the pavement deformation and deflection because uncertain compression of backfilling material. It would impact the passenger safety and road quality. The CLSM (Controlled Low Strength Material) is increasingly to become the popular new material due to it is with the feature as high flow ability, low deformation, short engineering time and low strength for convenient re-construction. In order to reach the target of construction offal decrement, available material to CLSM application would be excavated field soil, waste foundry sand, recycling aggregates, fly ash, slag, etc. As for the management of low strength recycle materials and in the view of strength tests, the quick cure (aging in 3 or 4 hours) required in practice has resulted in that the setting period is too short to implement destructive compression strength tests in due time. Therefore, this study is to propose a non-destructive testing method which can be applied for immediate strength tests. On the other hand, the flow of field engineers is too high and an active, efficient management is absent, hence the issue cannot be solved from its root. Aiming at this issue, this study is to develop a KMAP (Knowledge MAPs), which is to enrich the knowledge foundation of engineers and hence establish the practices of pavement recycle. [ABSTRACT FROM AUTHOR]

River dredging in the form of public works is an effective approach to recovering the riverbed with the ancillary benefit of providing a source of sand and gravel to supply construction projects with needed materials at a fair price. Sand and gravel account for at least 75 % of the materials used in concrete construction, therefore, the price of these aggregates has a considerable influence on the price of ready mix concrete. In consideration of environmental protection and sustainable resources as well as prevention of illegal sand mining, many local governments have imposed restrictions on sand mining, with adverse consequences for sand mining operators. This has had an impact on concrete batch mix plant and the construction industry. To make matters worse, mainland China imposed a ban on the one-way vending of sand and gravel to Taiwan in 2007, further driving up the price of aggregate. With the objectives of maintaining supply and stabilizing sand and gravel prices, this study investigated the current sand and gravel market in Taiwan. We analyzed the profits gained by public work administration, sand and gravel plants, and concrete batch mix plant during the manufacturing process and provided prices that conform to market demand. [ABSTRACT FROM PUBLISHER]