The enormous development on production of vehicles resulted in growing amount of waste tires rubber. Consequently, waste rubber is considered as one of the most waste materials that might cause environmental problems. Incorporating tires rubbers in concrete pavement has been widely studied as one of the promising and sustainable solutions to these current environmental problems. This paper explored the effect of replacing coarse aggregate with waste tires rubber according to their sieve sizes. Three replacement ratios were suggested to substitute the coarse aggregate in concrete of 5 wt. %, 10% and 15%. Two replacement techniques were chosen in order to investigate the rubber particle size. The results illustrated that the compressive strength reduced by 8.5, 51% for 5 to 15 % replacing from all particle sizes. While it shows lower percentage of 0.3 to 11%, 12 to 19% and 7 to 17% for replacing 5 to 15% from sieve #20 to #4.75, respectively. The dry density for all samples decreased slightly with increasing rubber percentage. Furthermore, water absorption ratios of the tested samples were comparable with the reference sample by replacing from each sieve separately. In contrast, it shows higher increase by replacing from all sieves.

The dried Iraqi marshlands were re-flooded after the year 2003. Because of the water shortage feeds the marshes during the last years, the re-flooded marshes began to dry again. The Al-Sanaf marsh is part of the Al Hammar marsh located in the Thi Qar province. It is not separated hydraulically from the Al Hammar marsh. The study suggested separating the two marshes by replacing the culverts under security dyke with uncontrolled weir to keep the area of Al-Sanaf marsh submerged. If there is any added water, it will cross from the suggested structure to the Al Hammar marsh. A hydrodynamic and water quality routing models (RMA2 and RMA4) were prepared based on mass conservation low, mass balance model, and four scenarios were applied for the Al-Sanaf marsh based on the incoming discharges. The suggested model was calibrated with field data measured in the marsh. The four suggested scenarios are to keep the requirement of the Al-Sanaf marsh restoration. The maximum submerged area of the marsh is 100 km 2 under any operation conditions while this area was reduced to 72 km 2 under low flow conditions (minimum inflow from the feeders). The three scenarios operated considering values of inflow from Euphrates River with the required inflow from Al Khamissiya canal to keep the minimum level of salinity in the submerged area. While the fourth scenario operated with the minimum value of discharge from all feeders.

In this study, a simulation tool, based on the combination of Geographic Information System (GIS) and Grid-Based Regional Slope-Stability Model (TRIGRS), is developed to assess and predict the snowmelt-induced landslides in areas of sensitive marine clays in the Ottawa region (Canada). Topographic, geologic, hydrologic, and geotechnical information of the study area, in addition to snowmelt intensity data for different periods, was required to conduct this modeling study. Snowmelt intensity records for periods of 6-48 h, 3-15 days, 25 days, and 30 days, as well as the information on historical landslides in the study area, were used to examine both the timing and location of shallow landslides due to snowmelt across the Ottawa region. The developed tool is validated by comparing the predicted landslide-susceptible areas with the historical landslide maps in the study area. A good agreement between the predicted and recorded historical landslides was obtained, which suggests that the developed GIS-TRIGRS based tool can predict relatively well the snowmelt-induced landslide susceptibility in the sensitive marine clays. The modeling results show that high slope areas of sensitive marine clays are more prone to snowmeltinduced landslides. As a result, this simulation tool could be used to assess and/or predict snowmelt-induced landslides in different areas of the Ottawa region, which is an important means for decision-making processes with respect to protecting the population and infrastructure against snow-melt induced marine clay landslides.

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