Le et al 2023a - Revision history

Rimni: /* 2. Methods of calculating bridge pier scour */

2023-11-24T10:06:30Z

‎2. Methods of calculating bridge pier scour

Rimni at 10:00, 24 November 2023

2023-11-24T10:00:35Z

Rimni: /* References */

2023-11-23T15:14:38Z

‎References

Lvthao at 16:26, 22 November 2023

2023-11-22T16:26:28Z

Lvthao at 16:21, 22 November 2023

2023-11-22T16:21:30Z

Lvthao at 16:20, 22 November 2023

2023-11-22T16:20:02Z

Lvthao at 16:18, 22 November 2023

2023-11-22T16:18:52Z

Lvthao at 15:24, 22 November 2023

2023-11-22T15:24:54Z

Rimni at 11:13, 22 November 2023

2023-11-22T11:13:59Z

Rimni at 10:25, 22 November 2023

2023-11-22T10:25:29Z

@@ Line 234: / Line 234: @@
 ===2.1.2 Caculating local Scour (<math display="inline">p = 1</math>%)===
-Two authors Truc and Khai introduced the formula for determining the largest local scour value at the bridge pier. This formula is cited in a book of author Nguyen Xuan Truc [8] . Based on the research results on the causes and development process of local scour on pier scour models in the hydraulic laboratory and the research results of foreign authors, a reasonable structural form of the local scour calculation formula has been selected. When <math display="inline">V =V_{ox}</math> (for mainstream piers),  Eq. (2) has the following simple form:
+Truc [8] introduced the formula for determining the largest local scour value at the bridge pier. Based on the research results on the causes and development process of local scour on pier scour models in the hydraulic laboratory and the research results of foreign authors, a reasonable structural form of the local scour calculation formula has been selected. When <math display="inline">V =V_{ox}</math> (for mainstream piers),  Eq. (2) has the following simple form:
 {| class="formulaSCP" style="width: 100%; text-align: left;"

@@ Line 20: / Line 20: @@
 ====2.1.1  General scour====
-Andreev [7] proposed a method to calculate the maximum general scour under the bridge (lower limit of scour) based on the analysis of the movement of alluvium particles in the mainstream and the river beach below the bridge. In the river beach part under the bridge, scour only starts when the velocity of water flowing under the bridge is greater than the allowed non-scour velocity (v<sub>ox</sub>) of the geological soil layer forming the river beach (v<sub>bc</sub>>v<sub>ox</sub>) and the scour will stop when the flow rate decreases to the allowed non-scour rate. In the mainstream, the flow rate is always greater than the allowable rate of non- scour of the riverbed’s geological layer and therefore the topsoil layer of the riverbed is always in a state of motion, but the river is not deeply eroded because there is a balance of alluvium along the river. Thus, the flow rate under the bridge is greater than the allowable rate without erosion, which is not the cause of scour in the mainstream and the deformation of the river under the bridge can only be explained by the imbalance of alluvium along the river. The overall scour under the bridge is calculated according to the principle of balance of sediment limit for the mainstream and the flow part with alluvium transport of Andreev [7]. The flow depth after scouring is determined according to Eq. (1)
+Andreev [7] proposed a method to calculate the maximum general scour under the bridge (lower limit of scour) based on the analysis of the movement of alluvium particles in the mainstream and the river beach below the bridge. In the river beach part under the bridge, scour only starts when the velocity of water flowing under the bridge is greater than the allowed non-scour velocity (<math>V_{ox}</math>) of the geological soil layer forming the river beach (<math>V_{bc}>V_{ox}</math>) and the scour will stop when the flow rate decreases to the allowed non-scour rate. In the mainstream, the flow rate is always greater than the allowable rate of non- scour of the riverbed’s geological layer and therefore the topsoil layer of the riverbed is always in a state of motion, but the river is not deeply eroded because there is a balance of alluvium along the river. Thus, the flow rate under the bridge is greater than the allowable rate without erosion, which is not the cause of scour in the mainstream and the deformation of the river under the bridge can only be explained by the imbalance of alluvium along the river. The overall scour under the bridge is calculated according to the principle of balance of sediment limit for the mainstream and the flow part with alluvium transport of Andreev [7]. The flow depth after scouring is determined according to Eq. (1)
 {| class="formulaSCP" style="width: 100%; text-align: left;"
@@ Line 234: / Line 234: @@
 ===2.1.2 Caculating local Scour (<math display="inline">p = 1</math>%)===
-Two authors Truc. N.X  and Khai. N.H introduced the formula for determining the largest local scour value at the bridge pier. This formula is cited in a book of author Nguyen Xuan Truc (2001) [8] . Based on the research results on the causes and development process of local scour on pier scour models in the hydraulic laboratory and the research results of foreign authors, a reasonable structural form of the local scour calculation formula has been selected. When <math display="inline">V =V_{ox}</math> (for mainstream piers),  Eq. (2) has the following simple form:
+Two authors Truc and Khai introduced the formula for determining the largest local scour value at the bridge pier. This formula is cited in a book of author Nguyen Xuan Truc [8] . Based on the research results on the causes and development process of local scour on pier scour models in the hydraulic laboratory and the research results of foreign authors, a reasonable structural form of the local scour calculation formula has been selected. When <math display="inline">V =V_{ox}</math> (for mainstream piers),  Eq. (2) has the following simple form:
 {| class="formulaSCP" style="width: 100%; text-align: left;"

← Older revision		Revision as of 15:14, 23 November 2023
Line 947:		Line 947:
	[7] Andreev O.V. Principles of designing regulating structures (in Russian). VNIIZhSi P, Moscow, 1954.		[7] Andreev O.V. Principles of designing regulating structures (in Russian). VNIIZhSi P, Moscow, 1954.

−	[8] Truc N.X. Design of highways and river crossing projects~~, Volume 3~~ (In Vietnamese). Educational Publishing House, Hanoi, 2001	+	[8] Truc N.X. Design of highways and river crossing projects (In Vietnamese). Volume 3, Educational Publishing House, Hanoi, 2001.

← Older revision		Revision as of 16:26, 22 November 2023
Line 947:		Line 947:
	[7] Andreev O.V. Principles of designing regulating structures (in Russian). VNIIZhSi P, Moscow, 1954.		[7] Andreev O.V. Principles of designing regulating structures (in Russian). VNIIZhSi P, Moscow, 1954.

−	[8] Truc N.X~~. (2001)~~. Design of highways and river crossing projects, Volume 3. Educational Publishing House, Hanoi~~. (In Vietnamese)~~	+	[8] Truc N.X. Design of highways and river crossing projects, Volume 3 (In Vietnamese). Educational Publishing House, Hanoi, 2001

@@ Line 234: / Line 234: @@
 ===2.1.2 Caculating local Scour (<math display="inline">p = 1</math>%)===
-Two authors Truc and Khai introduced the formula for determining the largest local scour value at the bridge pier. This formula is cited in a book of author Nguyen Xuan Truc (2001) [8] . Based on the research results on the causes and development process of local scour on pier scour models in the hydraulic laboratory and the research results of foreign authors, a reasonable structural form of the local scour calculation formula has been selected. When <math display="inline">V =V_{ox}</math> (for mainstream piers),  Eq. (2) has the following simple form:
+Two authors Truc. N.X  and Khai. N.H introduced the formula for determining the largest local scour value at the bridge pier. This formula is cited in a book of author Nguyen Xuan Truc (2001) [8] . Based on the research results on the causes and development process of local scour on pier scour models in the hydraulic laboratory and the research results of foreign authors, a reasonable structural form of the local scour calculation formula has been selected. When <math display="inline">V =V_{ox}</math> (for mainstream piers),  Eq. (2) has the following simple form:
 {| class="formulaSCP" style="width: 100%; text-align: left;"

← Older revision		Revision as of 16:20, 22 November 2023
Line 947:		Line 947:
	[7] Andreev O.V. Principles of designing regulating structures (in Russian). VNIIZhSi P, Moscow, 1954.		[7] Andreev O.V. Principles of designing regulating structures (in Russian). VNIIZhSi P, Moscow, 1954.

−	[8] Truc N.X. (2001). Design of highways and river crossing projects, Volume 3. ~~Book~~ Educational Publishing House, Hanoi. (In Vietnamese)	+	[8] Truc N.X. (2001). Design of highways and river crossing projects, Volume 3. Educational Publishing House, Hanoi. (In Vietnamese)

@@ Line 234: / Line 234: @@
 ===2.1.2 Caculating local Scour (<math display="inline">p = 1</math>%)===
-Two authors Truc and Khai [8] introduced the formula for determining the largest local scour value at the bridge pier. Based on the research results on the causes and development process of local scour on pier scour models in the hydraulic laboratory and the research results of foreign authors, a reasonable structural form of the local scour calculation formula has been selected. When <math display="inline">V =V_{ox}</math> (for mainstream piers),  Eq. (2) has the following simple form:
+Two authors Truc and Khai introduced the formula for determining the largest local scour value at the bridge pier. This formula is cited in a book of author Nguyen Xuan Truc (2001) [8] . Based on the research results on the causes and development process of local scour on pier scour models in the hydraulic laboratory and the research results of foreign authors, a reasonable structural form of the local scour calculation formula has been selected. When <math display="inline">V =V_{ox}</math> (for mainstream piers),  Eq. (2) has the following simple form:
 {| class="formulaSCP" style="width: 100%; text-align: left;"
@@ Line 947: / Line 947: @@
 [7]  Andreev O.V. Principles of designing regulating structures (in Russian). VNIIZhSi P, Moscow, 1954.
-[8] Truc N.X., Khai N.H. Calculation of pier scour (in Vietnamese). 1982.
+[8]   Truc N.X. (2001). Design of highways and river crossing projects, Volume 3. Book Educational Publishing House, Hanoi. (In Vietnamese)

@@ Line 565: / Line 565: @@
   |-style="text-align:center"
    |T18
-   |.000
+   |0.000
    |2.830
    |0.655

@@ Line 930: / Line 930: @@
 ==References==
-[1] E. M. Laursen, A. Toch. (1956) Scour Around Bridge Piers and Abutments
+<div class="auto" style="text-align: left;width: auto; margin-left: auto; margin-right: auto;font-size: 85%;">
-[3] Richardson, E.V. and Davis, S.R. (2001) Evaluating scour at bridges. 4th Edition, Federal Highway Administration Hydraulic Engineering Circular No. 18, FHWA NHI 01-001.
+[1]  Laursen E.M.,  Toch A. Scour around bridge piers and abutments. Iowa Institute of Hydraulic Research, Bulletin  No. 4, 1956.
-[4] Y. M. Chiew & B. W. Melville (1987). Local scour around bridge piers. Journal of Hydraulic Research, Volume 25, 1987 - Issue 1
+[2] Shen H., Schneider V.R.,  Karaki S. Local scour around bridge piers. Journal of the Hydraulics Division, 95:1919-1940, 1969.
-[5]. Dang Viet Dung (2011), Research and develop a method to calculate local scour at bridge piers'','' PhD thesis, University of Danang (In Vietnamese)
+[3] Richardson E.V.,  Davis S.R. Evaluating scour at bridges. 4th Edition, Federal Highway Administration Hydraulic Engineering Circular, No. 18, FHWA NHI 01-001, 2001.
-[6]. Nguyen The Hung, Nguyen Xuan Truc, Dang Viet Dung (2013).  Applying energy balance conditions for estimating local scour depths at bridge piers, The 14th Asia Congress of Fluid Mechanics - 14ACFM October 15 - 19, Hanoi and Ha Long, Vietnam.
+[4]  Chiew Y.M.,   Melville B.W. Local scour around bridge piers. Journal of Hydraulic Research, 25(1):15-26, 1987.
-[7] O. V. Andreev. (1954) Principles of Designing Regulating Structures [in Russian], VNIIZhSi P, Moscow
+[5] Dung D.V. Research and develop a method to calculate local scour at bridge piers (in Vietnamese). PhD Thesis, University of Danang, 2011.
-[8] Nguyen Xuan Truc and Nguyen Huu Khai (1982). Calculation of pier scour (In Vietnamese)
+[6] Hung N.T., Truc N.X., Dung D.V.  Applying energy balance conditions for estimating local scour depths at bridge piers. The 14th Asia Congress of Fluid Mechanics - 14ACFM, October 15-19, Hanoi and Ha Long, Vietnam, 2013.

@@ Line 610: / Line 610: @@
 {| class="wikitable" style="margin: 1em auto 0.1em auto;border-collapse: collapse;font-size:85%;width:auto;"
 |-style="text-align:center"
-! style="vertical-align:top" | Piers !! Shape factor <br> <math>K_d</math> !! Width of pier <br> <math>b</math> (m) !! Depth of water flow <br> <math>h</math> (m) !! Velocity <math>V</math> <br> (m/s) !! No-scour velocity <br> <math>V_{ox}</math> (m/s) !! style="vertical-align:top" | Rate <math>V</math>/<math>V_{ox}</math> !! Maximum local <br> scour depth <math>h_{cb}</math> (m)
+! style="vertical-align:top" | Piers !! Shape factor <br> <math>K_d</math> !! Width of pier <br> <math>b</math> (m) !! Depth of water flow <br> <math>h</math> (m) !! Velocity <math>V</math> <br> (m/s) !! No-scour velocity <br> <math>V_{ox}</math> (m/s) !! style="vertical-align:top" | Rate <br> <math>V</math>/<math>V_{ox}</math> !! Maximum local <br> scour depth <math>h_{cb}</math> (m)
 |-style="text-align:center"
 |T3