Claim Missing Document
Check
Articles

Found 2 Documents
Search
Journal : Civil Engineering Forum Teknik Sipil

UNJUK KERJA ALTERNATIF PENGENDALIAN BANJIR BATANG ANAI DAN BATANG KANDIS SUMATERA BARAT Eriza, Corri; Istiarto, Istiarto; Sujono, Joko
Civil Engineering Forum Teknik Sipil Vol 18, No 2 (2008): MEI 2008
Publisher : Civil Engineering Forum Teknik Sipil

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (432.344 KB)

Abstract

Flood occurs almost every year due to the floatation of Batang Anai and Batang Kandis. In 2001, the local authority made a plan to control the flood in both rivers, which was implemented in Anai-Kandis River Improvement with the alternatives of controlling flood by handling the river courses, such as improving and widening the river channel, and decreasing the peak of discharges by making dams or retarding basin. Performance of flood control structures are made of three alternatives based on the information gathered. First alternatives suggest for repairing the river course and widening the river channel (with levee) in both rivers and floodway in Batang Kandis. Second alternative is similar with the first alternative except negation the leeve in Batang Anai and replenishment of floodgate in Batang Kandis. Third alternative for Batang Anai is identical to the second alternative and also widening the river channel throughout Batang Kandis. The analysis includes the analysis of sufficiency of channel to drain the design discharge and sediment transport analysis for the alternative with the best performance, which both could be doing with auxiliaries of Software HEC-RAS version 4.0 betas. As the result, controlling river by repairing the river course and widening the river channel throughout Batang Anai and Batang Kandis (3rd alternative) gives the best performance comparing to the others alternatives, due to the fact that it could be able to canalize the design discharge of Q50 (1417 m3/s) in Batang Anai and Q25 (293 m3/s) in Batang Kandis. The simulation of transport sediment in Batang Anai with the 3rd alternatives implementation shows the biggest trend of erosion and deposition in a row, located next to National bridge downstream (RS 108) and precisely in downstream of RS 108 i.e., RS 107.
HIDROGRAF SATUAN: PERMASALAHAN DAN ALTERNATIVE PENYELESAIAN Sujono, Joko; Jayadi, Rachmad
Civil Engineering Forum Teknik Sipil Vol 17, No 2 (2007): MEI 2007
Publisher : Civil Engineering Forum Teknik Sipil

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (231.616 KB)

Abstract

Unit hydrograph is one of flood design method that commonly used in Indonesia. Problems emerge in the unit hydrograph application including high rainfall variability both time and space, lack of automatic rainfall data needed for unit hydrograph derivation. However, the output of the catchment system called hydrograph that represent all the phenomena in the system is available. So, effect of rainfall variability on unit hydrograph and the possibility to derive unit hydrograph based on hydrograph data without rainfall data need to be studied. Unit hydrograph derivation is done by using different rainfall input i.e. single station, rainfall catchment and inverse effective rainfall derived based on hydrograph alone. The resulted unit hydrographs are then used for design flood calculation. Results show that the resulted unit hydrographs vary among the different rainfall inputs. The difference in peak relative to unit hydrograph derived based on average rainfall for Bedog, Code and Winongo catchments could reach -18%, -30% and -11%, respectively. This result indicates that in the catchment studied, the rainfall variability is relatively high. However, the difference in flood peak is quite small, that is up to -12% for all the catchments. There is a trend that the station closest to the catchment centroid gives small bias in design flood relative to the design flood computed based on average rainfall.