International Journal of Ground Sediment & Water

59-70

Authors: Yang Jishan

Gravity erosion is active in the hilly-gully region of Loess Plateau which contributes large amount of sediment by conveying much earth into the valleys. Field observation on the gravity erosion was carried out in Qiaogou watershed. Erosion pins were used to measure erosion rate on the gully slope, and shear tests were done to discuss the effecting factors of the gravity erosion. Field survey showed that mainly small gravity erosions were occurred in Qiaogou watershed and which produce much sediment. Three types of small gravity erosion types, including loess grain fall, mass fall and slump, were measured, and their effecting factors were discussed. Study shows that the small gravity erosion are mainly controlled by the slope gradient, rainfall, weathering, etc. These influence factors can reduce the internal friction angle and cohesion of the intact loess and therefore lead to lowering the critical depth of the gravity erosion on the slope, this can explain the occurrence of the shallow gravity erosions on the slopes. Gravity erosion has different intensity in different evolution stages of the gully, so it is possible to estimate the intensity of gravity erosion by the evolution stages of the gully. © International Journal of Ground Sediment & Water, @ Sun Jichao. The website is https://ijgsw.eu.org/ http://ijgsw.net/

89-98

Authors: Wang Jia-xin; Gao Hui-qiao; Yang Chun-xia; Fan-Dongming; Wu Qing; Yang Ji-shan

Slope-gully system is the basic unit to study the erosion regularity and arrange the soil and water conservation measures. The study on the phase characteristics of the collocation relationship between runoff and sediment is very important for arranging soil and water conservation measures of adaptation to local condition. Based on the Key Laboratory of Yellow River Sediment Research of Ministry of Water Resources, the paper analyzed the process of runoff and sediment production in the slop-gully system of the soil erosion and the phase characteristics of the collocation relationship between runoff and sediment in the 3 different rainfall intensities by using the artificial rainfall simulation test method. The results showed that: (1)Under the condition of a certain underlying surface, there is a critical point in the process of soil erosion in the slope-gully system. Less than the certain rainfall intensity, the runoff and sediment yield increased greatly with the increasing rainfall intensity. Over the certain rainfall intensity, the increasing degree of runoff and sediment yield and the velocity of erosion evolution slowed down. (2) The rainfall intensity and rainfall are important factors for affecting the process of erosion and sediment yield. And the effect of rainfall intensity on runoff and sediment yield is even greater than the rainfall. (3)The collocation relationship between the runoff and sediment in the slop-gully system of the quasi shallow gully erosion stage was significantly different from that of sheet erosion stage and rill erosion stage. And with the same runoff yield, sediment yield increased significantly. Therefore, the soil and water conservation measures should be arranged according to the erosion development stage and the rainfall characteristics. © International Journal of Ground Sediment & Water, @ Sun Jichao. The website is https://ijgsw.eu.org/ http://ijgsw.net/

15-21

Authors: Sun Wen-jun; Song Yang; Guo Ke-xin; Zhu Xiao-yun

Considering the effect of reinforcement, and applying the cohesive force theory and Coulomb's earth pressure theory, thus the tensile failure theoretical formulae of lateral soil pressure for reinforced earth retaining wall is obtained. Analytical results show that cohesive force of reinforced earth has increment for the tensile failure. The lateral soil pressures value of wall back using proposed formula are smaller than using classical earth pressure theories of variable coefficient method. And the lateral soil pressure will increase with increasing of vertical spacing of reinforcement and decrease with increasing of the tensile strength of the reinforcement. The calculating results of this proposing method basically accord to results of the site tests in geogrid reinforced earth retaining wall. © International Journal of Ground Sediment & Water, @ Sun Jichao. The website is https://ijgsw.eu.org/ http://ijgsw.net/

32-40

Authors: Fan Dong-ming; Yang Chun-xia; Wu Qing; Wang Jia-xin; Yang Ji-shan

Using the automatic artificial rainfall system of MWR loess plateau soil and water loss process and control key laboratory, the researchers did simulation experiments of three different rainfall intensity to artificial simulation bare slope gully system, and analyzed erosion and sediment yield time-space distribution characteristics of slope-gully system. Results indicate that: erosion and sediment yield process of slope-gully system with the increase of rainfall duration showed a trend of increased volatility; the middle of gully slope and transition region of slope-gully system developed earlier and fastest-growing; ditch slope sediment yield and ditch slope runoff sediment concentration have the largest contribution to the export of slope-gully system runoff sediment concentration; in slope-gully system, lower-middle part and slope-ditch slope transition area are erosion prone areas; which shows that it is effective to control the erosion and sediment yield of loess plateau slope gully unit by adopting stress governance ditch and also measures of slope setting in practice. © International Journal of Ground Sediment & Water, @ Sun Jichao. The website is https://ijgsw.eu.org/ http://ijgsw.net/

52-58

Authors: Yang Xiao-liang

Aiming at the quality problems appear constantly in the field of construction engineering in China, this paper analyzes the perspective of construction contract and expounds the function of the construction contract in the engineering quality management. Compare the 2013 edition of the "construction contract (model text)" with the 1999 version of the FICIC "construction contract conditions" in the engineering quality of the relevant provisions of the analysis, to find the two contract model in the project personnel structure, engineering authority, sub-contractor selection, employer supply materials and mechanical, warranty five aspects of the difference. These differences will be the research direction of improves the quality of the construction contract clause. © International Journal of Ground Sediment & Water, @ Sun Jichao. The website is https://ijgsw.eu.org/ http://ijgsw.net/

1-4

Authors: Sun Jichao

Three stages of the shore riverbank collapse are a result of macro performance confrontation between the riverbank and the water pressure and the water penetration. The shore dike is in a kind of equilibrium, which may lean to the active water pressure (permeate), or may also lean to the passive pressure (permeate). When the shore dike is in the condition which leans to the active water pressure (permeate), the rising water level will low the safety of the shore dike and the embankment easily collapse. In this paper, the three kinds of collapse are connected together. In this way, the natural laws can be obtained, and the engineers in the field can do better with this understanding. © International Journal of Ground Sediment & Water, @ Sun Jichao. The website is https://ijgsw.eu.org/ http://ijgsw.net/

9-11

Authors: Sun Jichao

Dissertation Abstract from Dr. Sun Jichao © International Journal of Ground Sediment & Water, @ Sun Jichao. The website is https://ijgsw.eu.org/ http://ijgsw.net/

13-14

Authors: Sun Jichao; Zhou Fuhua; Gao Quanchen

Engineering and Disaster News from China. © International Journal of Ground Sediment & Water, @Sun Jichao. The website is https://ijgsw.eu.org/ http://ijgsw.net/