Horizontal Slice Method for the Stability Analysis of Reinforced Slopes

Relevant national codes usually require the transmitting coefficient method to be employed for the stability analysis of slope reinforcement, in which sliding mass is usually divided into a number of vertical slices.For some support technologies, such as rock bolting and anchor cable, the intersections between the slices and the anchor bar, and the forces mobilized in the reinforcements are different from the assumptions in this method.Thus the transmitting coefficient method confronts some difficulties during practical applications, which would influence the project quality of reinforcements.A new Horizontal Slice Method was proposed based on the overseas relevant literatures to overcome these difficulties in the stability analysis of rock bolting and anchor cable slopes.     

Research on Evaluation of the Slope Stability Based on the Extension Theory

The stability of rock-mass slopes is a very complicated system which is controlled by lots of factors. It is always a very important research subject to evaluate the slope stability reasonably through some evaluation methods. Based on matter-element theory and dependent function,the extension theory is applied to evaluate the stability of rock mass slope,and the extension method for the stability of rock mass slopes is proposed. Taking a real slope project for example,based on the reasonable selection of evaluation factors of slope stability,an extension model for evaluation of slope stability is built,whose result is contrasted with the fuzzy evaluating one. As a result, it is practical and feasible to apply the extension method to estimate the rock slope stability.     

Study on high and steep slope stability Based on 3D laser scanning

Dangerous mountain construction projects block of high and steep slope stability is the important issue of security and disaster prevention, investigation on the surface of the dangerous mountain high and steep slope rock mass structure is the key to the analysis of the problem. The high slope of a major project of the Lancang River, the application of 3D laser scanning technique to study the long-distance survey analysis of rock mass structure analysis method to analyze the distribution of the surface space of the high and steep slope rock mass structure, statistical analysis direction of the advantages of the structure surface and the distribution of rock blocks, as the basis for the application of limit equilibrium analysis method to study the stability of rock blocks of the high and steep slope.     

“2014年青岛世园会”百果山园区岩壁景观的生态恢复与重建

由于长期开采花岗岩建筑石材,“2014年青岛世园会”百果山园区的花岗岩丘陵上遗留有6处开采石材形成的岩石崖壁。在园区建设过程中,将这6处岩石崖壁分为坡度70°以下的岩石崖壁和坡度70°以上的岩石崖壁2类,并遵循可行性原则、地域性原则和美学原则,分别提出了2类岩石崖壁景观的生态恢复与重建措施。其中,坡度70°以下的岩石崖壁可采取底层采石坑回填、“钻孔植绿”与“筑巢复绿”等措施进行生态恢复与重建;坡度70°以上的岩石崖壁可采取布鲁特罩面网垂直绿化技术、人工植生槽与顶部筑营养槽相结合,建造人工流水景观,建造人造雾喷景观,融入雕塑艺术等措施进行生态恢复与重建。     

Discussion on Methods for Determining Cracking Angle of Rock Slope

Many mountainous cities are facing slope problems during project construction. At present, there are two methods to determine cracking angle for rock slope, namely, the method from "Technical Specification for Retaining Structure in Excavation" and the method from "Handbook of Engineering Geology". However, there is obvious difference between cracking angles of rock slope by these two methods. In this paper, the theoretical formulas of these two methods are derived and compared. Based on analyzing the results of FLAC numerical simulation for soft rock slope, it is concluded that the cracking angles of rock slope determined by the "Handbook of Engineering Geology" are more reasonable and safe.     

QTL for delayed bolting after winter detected in leaf beet (Beta vulgaris L.)

Growing sugar beet (Beta vulgaris L. ssp. vulgaris) as a winter crop in cool temperate climates is expected to increase yield potential. However, this requires bolting resistance after winter. One strategy to achieve complete bolting resistance is to accumulate genes for bolting delay from various genetic resources within the B. vulgaris gene pool. To identify such genes, a QTL mapping was performed in a segregating population derived from a biennial leaf beet with delayed bolting after winter. The population was tested for bolting delay after winter in two different experiments with natural or artificial vernalization. Three QTL for bolting delay were mapped on linkage groups 3, 5 and 9 affecting bolting time by up to 19 days. These QTL could be combined with recently reported bolting QTL to develop a winter sugar beet with complete bolting resistance.     

Deformation and Failure Model Test of Steep Dip Excavation Bedding Slope under the Action of Seismic Load

In the Wenchuan earthquake, steep dip bedding slope is a kind of slope that seismic mountain disaster very development and the slope earthquake disaster is often exacerbated by the excavation. In order to reproduce the process and analysis regularity of slope deformation and failure under the action of seismic load. The author chooses San Shuping landslide located Pingwu County as the typical examples of steep dip excavation damage bedding slope, and the indoor physical model test of slope deformation and failure under the action of seismic load are carried out. The results show that slope deformation and failure is intensified by the excavation. Collapse and sliding is the main form of failure and the results consistent with the field investigation. From the whole process of deformation and failure of view, it can be divided into the four stages. First, the initial phase of the earthquake. A wedge rock by excavation small slides along the rock layers and the slope toe stress increase sharply under the action of seismic load in this stage. Second, rock layers by excavation break-bend at slope toe. Third, the rock layers by excavation overall decline stage. Last, the rock slide blocked and dumping.     

A marker-assisted analysis of bolting tendency in sugar beet (Beta vulgaris L.)

Bolting tendency in sugar beet varies among breeding lines and cultivars. Four crosses were made between breeding lines susceptible and resistant to bolting in order to study the genetic basis of bolting tendency. Bolting percentage in F₂, after 8 weeks of low temperature treatment, varied among the crosses, suggesting a complicated genetic control of bolting tendency. Different segregation ratios were observed, in particular, between families derived from the bolting F₁ plants and those from their non-bolting siblings, the former families showing a significantly higher bolting percentage than the latter. A marker-assisted analysis with seven isozyme loci, Ak1, Gdh2, Idh1, Lap, Mdh1, Pgi2 and Pgm1, revealed that a locus with marked effect on bolting tendency was located near Idh1. Because of a close linkage of Idh1 with B for annuality, the gene tagged by Idh1 appeared to be equivalent or similar to B′ for easy bolting allelic to B as reported by Owen et al. (1940). The results obtained suggest that the B locus may not only have an important role in determining growth habits but also control various degrees of bolting tendency in individual sugar beet plants. A linked pair, Ak1-Lap, and Pgi2 also were found to affect bolting tendency, although their effects varied depending on the crosses and families tested. This revised version was published online in July 2006 with corrections to the Cover Date.     

Simulation Study of Water Quality for the Three Gorges Reservoir in Chongqing

In order to survey the degree of stability of dangerous rock slope and get reliable theoretical foundation about the slope restoration, earth stress measuring is performed in the engineering project through drilling on the slope surface. The survey is conducted by means of complete temperature compensation and automatic recording. In terms of experimental data, the computing ram of earth stress works out the magnitude, direction, inclination of the earth stress and their distribution. The result supplies theoretical base for the design and working of slope and dangerous rock control engineering, which has been proved to fine effects in the fields of society, security,environment, and economy in its practice.     

Development and Failure Principle of Differential Weathering Overhanging Rock

Differential weathering overhanging rock by hard rock and soft rock interlayer is common for geological failure.To study the influence of ground stress in rock slope and cave deepness to differential weathering overhanging rock,a mechanical model was proposed.And hollow cylinder stress meter was used to test and analyze on site ground stress at Hongyadong in Chongqing.Moreover, the development range of overhanging rock was determined.And a case studywas used to analyze the relationship among tension ground stress, cave deepness and growth of controlling crack.A method for forecasting overhanging rock failure pattern was proposed.     

Technology of Stress Relief by Overcoring Used in Dangerous Rock Slope

In order to survey the degree of stability of dangerous rock slope and get reliable theoretical foundation about the slope restoration, earth stress measuring is performed in the engineering project through drilling on the slope surface. The survey is conducted by means of complete temperature compensation and automatic recording. In terms of experimental data, the computing ram of earth stress works out the magnitude, direction, inclination of the earth stress and their distribution. The result supplies theoretical base for the design and working of slope and dangerous rock control engineering, which has been proved to fine effects in the fields of society, security,environment, and economy in its practice.     

春甘蓝抽薹的生理与相关基因转录分析

本研究以高代自交获得的4份具有不同抽薹时间且遗传稳定的春甘蓝品系为材料,在观察其园艺学性状的基础上,分析了抽薹性状与可溶性蛋白和可溶性糖含量之间的关系,结果显示,耐抽薹春甘蓝品系的可溶性蛋白和可溶性糖含量低于不耐抽薹的,抽薹前春甘蓝的可溶性蛋白和可溶性糖含量也均低于抽薹后的.进一步的转录分析结果表明,5个与植物抽薹开花...     

Laboratory similar model test investigation of prestressed anchor rope strengthened slope fractured rock mass

Now in the highway construction of the mountain area, fractured rock mass slope always strengthened by the anchor rope. In order to investigate the strengthen effect of the slope fractured rock mass strengthened by the prestressed anchor rope, laboratory similar model test was designed and preceded. By the self-made facilities, a new method of modeling prestressed anchor rope was used in the test. Nylon ropes and the aluminum flakes were used to model the anchor rope and discrete rock mass joints. Gypsum based mix material was used to model rock. According to the real slope engineering site circumstances, six sorts of different disposed prestressed nylon rope strengthened model specimens and the specimens without prestressed nylon rope were made by the similar theory. With the test results, the strength and deformation properties of different model specimens were investigated. Comparison to different anchor effects of the different model specimens was made. The final analysis shows that in order to make full use of the anchor rope's strengthen ability, anchor rope should be disposed perpendicularly to the fracture structure rock mass's main joint direction and should be placed in the upper or top area of the fractured rock mass slope.     

白菜抽薹相关性状遗传分析

研究与白菜抽薹相关性状的遗传特性,为白菜类作物晚抽薹育种应用提供理论依据。试验以抽薹指数、开花时间和薹长5 cm时间分别作为抽薹早晚的评价标准,应用植物数量性状主基因+多基因混合遗传模型,对晚抽薹大白菜高代自交不亲和系(P1)和易抽薹欧洲白菜型油菜自交系(P2)及杂交所获得的F1、B1、B2和F2各世代群体进行联合遗传分析。结果表明,抽薹指数性状和薹长5 cm时间性状均受2对加性-显性-上位性主基因控制（B-1模型）,开花时间性状受1对加性-显性主基因+加性-显性-上位性多基因控制（D模型）。与抽薹相关的3个性状各分离世代(B1、B2、F2)均未检测到多基因遗传,其主基因遗传率分别为抽薹指数96.22%(B1)、93.33%(B2)、93.55%(F2);开花时间70.68%(B1)、70.68%(B2)、70.64% (F2);薹长5 cm时间79.44%(B1)、79.55%(B2)、79.38%(F2),环境条件对白菜抽薹性状影响较大。由此可知,对白菜抽薹性状的遗传改良应以主基因为主,适宜在早期世代进行选择并注意环境条件影响。     

高温诱导叶用莴苣抽薹过程中内源激素含量变化分析

为探讨高温诱导叶用莴苣抽薹过程中内源激素的变化规律,进而揭示内源激素与抽薹的相互关系,以易抽薹叶用莴苣品种‘G-B30’为试材,利用植物生长箱模拟夏季高温,分析了高温诱导叶用莴苣抽薹过程中茎和叶的赤霉素(GA)、生长素(IAA)、茉莉酸甲酯(MeJA)、脱落酸(ABA)、玉米素核苷(ZR)、油菜素内酯(BR)含量的动态变化。结果表明,高温处理下,茎和叶在抽薹期（高温处理7天后）GA含量均显著高于抽薹前（高温处理前5天）。与对照相比,高温组茎中GA含量显著高于对照。高温处理组茎和叶中IAA、ABA、ZR含量抽薹期显著高于抽薹前,且高温组进入抽薹期时IAA、ABA含量也显著高于对照组。茎和叶BR含量表现为抽薹期显著低于抽薹前。与对照相比,高温组中抽薹期茎中BR含量明显降低而叶的BR含量无明显变化。高温处理组中茎和叶的MeJA含量均显著高于对照,且抽薹期显著低于抽薹前。综上所述,推测高水平的内源GA、IAA、ABA和ZR含量,低水平的BR可能促进叶用莴苣抽薹,而MeJA与叶用莴苣抽薹的关系不大。     

土壤砾石的分布及其对水文过程的影响

(西南大学资源环境学院,重庆 400716)     

大白菜种质资源抽薹性及其遗传性的研究

以现蕾期和抽薹期为指标,对98份有代表性的大白菜种质资源的抽薹性进行了2年的调查和统计,结果显示,大部分材料从播种到现蕾的时间为101~112 d,占73.8%,超过116 d现蕾的材料仅占8.7%;从播种到抽薹的时间为105~116 d,占75.1%,超过120 d抽薹的材料仅占10.1%,青麻叶类型晚抽薹材料所占比率更低。对3组不同抽薹性材料组合后代DH系群体抽薹期观察统计结果显示,抽薹期相近的双亲后代抽薹期的分布较集中,双亲抽薹期相差较远的后代抽薹期的分布较分散。比早抽薹亲本抽薹早的后代DH系普遍存在,但比晚抽薹亲本抽薹晚的后代DH系极少。     

An EMS mutagenesis protocol for sugar beet and isolation of non-bolting mutants

An annual sugar beet line homozygous for the dominant gene for early bolting (B) has been mutagenized with different doses of ethylmeth‐anesulfonate (EMS). Approximately 15 000 M1 seeds were treated with EMS doses between 0.5 and 1% for 4, 6, 8, 12 and 14 h. Among 10 066 M1s, plants with chlorophyll defects and other abnormalities were found. Germination rates ranged between 30 and 100%, whereas the fertility of M1s dropped to 36%. A dose of 1% EMS applied for 8 h was found to yield an acceptable rate of M2 sterility (16%). Exactly 0.5% of the M2 families contained plants with altered bolting behaviour. After selfing these M2 plants, five non‐bolting M3 lines were selected. These plants do not exhibit shoot elongation even after cultivation under long‐day conditions. Thus, they are homozygous for new mutagenized, recessive non‐bolting alleles. Moreover, four M3 lines showed delayed bolting which was clearly different from the early bolting parent. This demonstrates varying activities of the bolting gene due to different mutational events.     

Violent-slide rock avalanche and excitation effect of perilous rock

The physical model of perilous rock avalanche excitation effect is deudofed based on the effect of the main factors, such as weight and fissure water pressure. It quantizes the interaction of perilous rock masses through the energy point of fracture mechanics and wave theory, and gains the departure rate formula of landslide body at momentary avalanche. The particle displacement rate calculation method of perilous rock medium under the action of excitation waves is developed based on the formation of perilous rock avalanche excitation waves and the spread mechanism in slope rock formation. The example shows that the analysis results established are coincident with actual situation. Some scientific basis is provided for the further research of perilous rock damage and evolutionary mechanisms.     

Determination of the genetic variation in the effect of temperature and daylength on bolting of Brassica campestris L.

Summary Effects of temperature and daylength on the bolting of a number of B. campestris accessions were investigated both in the open and in the IVT phytotron. From the results it was concluded that low temperature and genotype are the predominant factors with respect to bolting. Daylength has rather limited influence. One cultivar bolted more than 12 weeks earlier at 10 and 14°C than at 18°C. On the other hand some cultivars did not require vernalization at all.At 14°C and short daylength, depending on genotype, the period of time between sowing and 50% bolting ranged from 8 to 30 weeks. At this temperature the stimulating effect of long day (24 h), depending again on the genotype, ranged from 0 to 4 weeks. The genotypes most resistant to bolting appeared to be the stubble turnips (B. campestris ssp. rapa).In terms of seed(ling) vernalization at 5°C the cold requirement ranged from 0 to more than 3 weeks, depending on the genotype. The required vernalization periods at 5°C can be used as a criterion in screening for resistance to bolting.