Long-term prediction of rainfall over a catchment is a challenge for hydrologists. It is required for water resources management, hydropower energy forecasting and flood risks assessment in river basins. Several large scale climate phenomena affect the occurrence of rainfall around the world i.e El Nino Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) are most famous for their effect on India, North and South America and Australia. This study is motivated to evaluate the performance of Statistical Downscaling Model (SDSM) developed by annual and monthly sub models for rainfall downscaling from Global Climate Models (GCMs) over the two districts in Sarawak. It is noted that the monthly sub-models have better performance over the annual sub-models. However, both monthly and annual sub-models have poor correlation with the recorded rainfall for the calibration and validation period. Results indicate that both stations show increasing trend in the future annual rainfall under H3A2 and H3B2 scenarios of HadCM3. SDSM predict that the annual rainfall at Belaga and Limbang is expected to increase by 37.8% and 22.7% respectively by 2074. Overall the SDSM approximates the average rainfall very well during the calibration and validation period but the correlation between observed and forecasted rainfall was not so good. And there is a need to improve the statistical downscaling modelling to develop better correlation between predictand and predictors to have better model performance over the wet regions like Sarawak.

This paper describes and analyses a series of tests on one-way spanning slabs, which were carried out at Imperial College London to investigate the influence of peak construction loads on long-term tension stiffening and slab deflections. The work was carried out to investigate the validity of conclusions drawn from the first author's back analysis of deflection data in the Cardington in situ concrete building, which suggested that long-term deflections in slabs could be governed by short-term construction and in-service loads. An improved method is proposed for taking account of the effect of peak construction loads on long-term slab deflections. The method is shown to be more accurate than the rigorous method in Concrete Society Report TR58 which is based on the first authors' analysis of slab deflections at Cardington.

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Recent research has questioned the validity of bond-slip relationships owing to the 'necessity for the concrete to be able to slip past the ribs on the bar'. Conversely, it is suggested in this paper that bond-slip models are simply a numerical device that relates bond stress to the relative displacements between the concrete, which surrounds the internal cracking zone, and steel. This paper shows that the short-term response of a reinforced concrete tension member with a central reinforcement bar is predicted well by a one-dimensional non-linear finite-element analysis incorporating a trilinear idealisation of the Model Code 1990 bond-slip relationship. The authors' analysis is significant since it is shown to predict many of the trends in behaviour observed in tests associated with tension stiffening and cracking. Different approaches are adopted in Eurocode 2 (EC2) (2004) for modelling tension stiffening in the calculation of crack width and mean axial extension. These approaches are reviewed in the light of the authors' finite-element analysis and existing experimental data. The EC2 models for mean axial strain are shown to be reasonable but the crack spacing formula overestimates crack spacing in the tension members considered in this study.

These Water resource projects and hydraulic engineering works have been developing rapidly throughout the world, thus prediction of water roughness coefficient is becoming an importance criteria for the designs of hydraulic related structure like open channel, and dam structure. The purposes of this research are to determine the effect of roughness on discharge and study on the factors that affect roughness coefficient. The roughness coefficient for this study is expressed in terms of Manning’s n. Experimental works were carried out to study the effect of roughness by using flumes (8m x 0.3m x 0.4m) with different types of roughened bed such as 2mm grain size plate and 5mm grain size plate. The experiments were being tested with various flow rates for slope equal to 1:300, 1:600 and 1:900 to determine the effect of slope on roughness coefficient. The results of the experimental study were presented and shown that the effect of surface roughness, material grain size, channel slope, and Manning’s roughness coefficient on flow rate. For the range of conditions tested, the discharge was found to be decreased as roughness coefficient increase. From the experiments, it shows smoother surface is having lower roughness coefficient and less retarding effect on the water flow, higher flow rate is produced. As conclusion, flow rate and roughness coefficient were influenced by bed roughness and slope.