【文章內容簡介】 把這個區(qū)域作為無效流動區(qū)域也同樣會起作用。Figure Overbank flow area outside of the main channel at river station cross section 1747 在主渠道外，橫截面1747的河流位置使流動區(qū)域大坡度轉彎從Cross Section Data編輯其中，選擇河流位置1747。下一步，選擇Options | Levees來展示XS Levee Data對話框。從此對話框中，定義一個位置和海拔值，使其將阻止流動進入左邊的凹陷區(qū) Levee Analysis 防洪堤分析從HECRAS的主窗口，選擇Run /Steady Flow Analysis 來打開Steady Flow Analysis 對話框。在此對話框中，選擇File /Save Plan 來保存新的計劃。Title鍵入“Plan 2:Levee”,然后選擇OK。通過選擇Compute按鈕來進行防洪堤上平穩(wěn)流動的分析。檢查1747處河流位置的結果?，F(xiàn)在500年的洪水被容納在河渠的兩岸內。Figure Flow is now contained within the river banks 流動包含在河流兩岸內.你可以在Steady Flow Analysis 對話框中通過選擇File/Open Plan 來在各種計劃間切換。這個操作將把Open Plan File窗口展現(xiàn)出來。 Interpolating Additional Cross Sections 插入另外的橫截面從HECRAS中瀏覽橫截面流量時，在一些橫截面中，你會發(fā)現(xiàn)下列警告信息：? The velocity head has changed by more than ft (). This may indicate the need for additional cross sections.（），這將預示著需要額外的橫截面。? The energy loss was greater than ft () between the current cross section and the previous cross section. This may indicate the need for additional cross sections.（），這將預示著需要額外的橫截面? The conveyance ratio (upstream conveyance divided by downstream conveyance) is less than or greater than . This may indicate the need for additional cross sections.流通比例（上游的流通除以下游的流通），這將預示著需要額外的橫截面。因此，為了改善流出量的結果，額外的橫截面需要被加在河流的模型上。HECRAS將自動地在已經定義的橫截面之間插入新的橫截面。當額外的橫截面數(shù)據可獲得時，插入的橫截面的數(shù)據不應該被使用。一個河流流程的3維圖解顯示了當前定義的橫截面。這個圖解可以通過選擇View /XYZ Perspective Plots來顯示出來。Figure XYZ Perspective Plot for the currently defined cross sections 當前定義的橫截面的XYZ的各自圖解要想插入額外的橫截面，從Geometric Date 編輯器上選擇Tools /XS Interpolation /Within a Reach 來顯示XS Interpolation by Reach 窗口。Maximun Distance Between XS’s鍵入“200”，然后選擇Interpolate XS’s 按鈕。Geometric Editor 幾何編輯器Ctrl Right Click allows you to measure a line [ Ctrl] 加單擊右鍵允許你測量線的長度Horizontal Roughness 水平的粗糙程度Manning Roughness Values 配置粗糙值Horizontal Roughness Subareas 水平粗糙分區(qū)Other Cross Section Related Data 其他橫截面相關數(shù)據Add or subtract a constant to the stations or elevations 給位置或海拔加上或減去一個常量Scale up or down the left overbank, channel, and right overbank stationing逐步增加或降低左側河灘，河渠，和右側河灘配置62Other Cross Section Data 其他的橫截面數(shù)據_ Flow Length and Overbank Stations 流動長度和河灘位置_ Ineffective Flow Area 無效的流動區(qū)域_ Levee (not in HEC2) 防洪堤（不在HEC2中） _ Obstructions (not in HEC2) 阻礙物（不在HEC2中）w _ Profile Adjustment 剖面調整Defining Flow Lengths 定義流動長度_ Channel Flow Length 河渠流動長度_ Left and Right Overbank Flow Lengths 作用河灘流動長度_ May change with increased flooding 可能隨著增加的洪水改變63Defining Flow Lengths (Low Flow) 定義流動長度（低的流動）Defining Flow Lengths (High Flow) 定義流動長度（高的流動）64Multiple Horizontal Roughness 多重的水平崎嶇SubSections 下列部分Stationn4n5n6n7n3n2n1X1X2X3X4X5X6X7Elevation Vertical Roughness 海拔 垂直崎嶇65Ineffective Flow Area (HEC2 style) 無效流動區(qū)域（HEC2樣式）_ Define a left and right ineffective flow (encroachment) station定義一個左右無效流動（侵蝕）位置_ Does not change wetted perimeteruses ground geometry for wetted perimeter不要改變侵潤周邊—利用地面幾何學_ Once WSEL overtops, then area bees effective again (considers this flow area)一旦WSEL高出，這個區(qū)域就恢復有效（考慮這個流動區(qū)域）_ Otherwise, mark as “Permanent” and ineffective area is never considered available for flow否則標明“永久”，無效區(qū)域從不會被看成可得到流動Ineffective Flow Area (HEC2 style) 無效流動區(qū)域（HEC2樣式）Ineffective Flow Area 無效流動區(qū)域Right Ineffective Flow 右無效流動Elevation 海拔Right Ineffective Flow 右無效流動Station 位置Left Ineffective Flow 左無效流動Elevation 海拔Left Ineffective Flow 左無效流動Station 位置66Ineffective Flow Area (HECRAS style) 無效流動區(qū)域（HECRAS樣式）_ Up to 20 multiple areas can be defined at a cross section在一個橫截面有近20個重區(qū)域可以被定義_ Does not change wetted perimeteruses ground geometry for wetted perimeter不要改變侵潤周邊—利用地面幾何學_ Once WSEL overtops, then area bees effective again (considers this flow area)一旦WSEL高出，這個區(qū)域就恢復有效（考慮這個流動區(qū)域）_ Otherwise, mark as “Permanent” and ineffective area is never considered available for flow否則標明“永久”，無效區(qū)域從不會被看成可得到流動Ineffective Flow Area(HECRAS style) 無效流動區(qū)域(HECRAS樣式)Elevation 海拔Station 位置18051800179517901785 17800 500 1000 1500Ineffective Flow Areas 無效的流動區(qū)域67Ineffective Flow Area 無效的流動區(qū)域_ Removes flow area from cross section until test elevation is exceeded 從橫截面移走流動區(qū)域直到測試的海拔被提高_ Once WSEL overtops, then area bees effective again (considers this flow area)一旦WSEL高出，這個區(qū)域就恢復有效（考慮這個流動區(qū)域）_ Otherwise, can mark as “Permanent” and ineffective area is never considered available for flow否則標明“永久”，無效區(qū)域從不會被看成可得到流動_ Decreases cross sectional area 減少橫截面的區(qū)域_ Does not decrease storage volume 不減少存儲量_ Does not add wetted perimeter 不增加侵潤周邊Conveyance Obstructions 流通障礙物_ Normal (HEC2 style) or Multiple Areas 正常的（HEC2樣式）或多重的區(qū)域_ Up to 20 multiple areas can be defined at a cross section在一個橫截面處20個多重區(qū)域可以被定義_ Similar to HECRAS Ineffective Flow Area dialog, however increases wetted perimeter與HECRAS無效流動區(qū)域窗口相似，但增加了侵潤周邊68Conveyance Obstructions 流通障礙物_ Permanently removed from cross section 從橫截面中永久地移開_ Decreases cross sectional area 減少橫截面的區(qū)域_ Increases wetted perimeter along sides and top of obstruction沿著障礙物的兩邊或頂端增加侵潤周邊_ Two types of blocked obstructions: 兩種類型的阻擋障礙物：_ Normal blocked obstructions 正常的阻擋障礙物_ Multiple blocked obstructions (up to 20 per cross section)多重的阻擋障礙物（每個橫截面20個）Conveyance Obstructions流通障礙物69Conveyance Obstructions流通障礙物ElevationStation1805180017951790178517800 500 1000 1500Left obstruction Right obstruction 左障礙物 右障礙物Conveyance Obstructions 流通障礙物Normal Obstructions Type (HEC2 like)正常的障礙物類型70ElevationStation1805180017951790178517800 500 1000 1500ObstructionsConveyance Obstructions 流通障礙物Multiple Obstructions Type 多重的障礙物類型 Levee Description 防洪堤描述_ Define a left and right station 定義一個左右位置_ Replaces the overbank elevation data entry that was available in HEC2 (no longer available in HECRAS)重新設置在HEC2中可獲得的河灘海拔數(shù)據條目（在HECRA