No abstract

This paper reviews the literature available on the subject of the durability of concrete sewer pipes and the corresponding rehabilitation technologies. An introduction related to the importance of the sewer system in urban life and its durability issues was first discussed as most people did not recognise the scale and complexity of the underground sewer system. Then the recent development of alternative binder materials or filler materials to improve the acid resistance of concrete was specified. For instance, the effects of alternative binders on the hydration products and the mechanism of biogenic corrosion were discussed in detail. The paper ends with the current rehabilitation technologies and the structural performance of rehabilitated sewer pipes. Also, some suggestions associated with future research were made.

Combined pile raft foundation (CPRF) is one of the emerging concepts for providing a cost-effective and efficient solutions for heavily-loaded structures. However, predicting the behaviour of such foundations, especially the load sharing between raft and pile is a challenge due to its inherent complex interactions. Existing analysis methods are either bound within a range of simplifying assumptions or sometimes computationally demanding. Hence, an attempt has been made to evolve a simple and easily implementable methodology, considering non-linear degrading behaviour of soil in a rational manner. The approach has first been validated with measured response during an experimental centrifuge testing of a CPRF in soft Malaysian kaolin clay and an instrumented bridge (Impulsora) founded in soft clayey soil. Subsequently, a range of comparative parametric evaluation of load sharing and settlement characterstics has been carried out which has indicated the importance of pile layout, length and numbers to arrive at a safe and economic design.

No abstract

No abstract