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Orthogonal experiments at concrete materials proved: notable errors will occur when using chemical catalyzing to predict the concrete strength. Errors are unavoidable since such methods have neglected much factors. Ground on test data, effects on concrete intensity were analyzed with changes of sand ratio, bigger aggregate, and environment humidity, cement components. Error origins of concrete intensity were found, and the fact of avoidless errors from chemical catalyzing was notarized. Materials testing combining with fieldwork, new technique was proposed for monitoring quality of fresh concrete in building site. So hidden trouble would be known betimes before elementary solidification in concrete. Practices indicated that this technique is simple and speedy, it can avoid the loss of doing over again in concrete structures and can effectively improve quality of concrete engineering.

Found on data of accelerated life test, the relationship between outward disease of structural concrete and holistic deterioration of building was analysed. The results indicated that: outward diseases of structural concrete, such as abrasion, scour erosion, and peeling, carbonization etc, are not hypostatic breakage for holistic building, so could not be regarded as the key points of deterioration identification at building. Deterioration appraisement should be focused on detections of engineering indices relating to structural inbeing quality and analyses of multifarious remainder relating to bearing capacity. Only in this way, deterioration degree of structural concrete and efficacious repair indices could be factually incarnated. Ground on testing multifarious bearing capacities, deterioration identification of concrete buildings was founded, and remedy principles corresponding to inbeing deterioration indices were put forward.

Effective unit weight, inner friction angle and cohesion are the main engineering indices of rock-soil mass anti-slide. Deviant leakage brings about obvious decrease of effective unit weight, inner friction angle and cohesion under combined action of thrust, buoyancy, and lubrication. So as to slip in unstable rock-soil mass. Deviant leakage schleps out weensy particles, induces seepage failure, so geotechnical engineering would collapse. Therefore the reasonable anti-leakage in unstable mountain is one of the key technologies that urgently to be solved in geotechnical engineering. Combined with the typical landslide geology, several groundwork anti-leakage were studied for earth-rock dam, correlative processes and technologies were discussed, and construction parameters were designed. The abnormal situations that may occur in construction were analysed, and preparative schemes were put forward. The results had been validated in practical engineering.

Resources of memory are frequently used times without number for reducing cost of control system. Rewriting in memory would cause occasional hardware conflict when especial data are inputted or are calculated, thereby system faults even accidents are elicited. Origin of occasional malfunction was analysed in automatic control system, necessity of program storage separate from data storage was discussed, and the notion was put forward that resource allocation of memory should be compatible with the system function. So dead halt owing to codes cover each other could be avoided, and reliability of measurement or control system could be effectively improved.

Laterite dams are chronically eroded by chloride in acidic reservoir water, and the fact is confirmed by dam safety checkups. Based on chemical analysis of water-soil interaction, accelerated life tests of dipping in HCl solution were designed for laterite. Multi-team engineering indices and microstructure characteristics of deteriorated laterite were compared and analyzed, changes of ion concentration in exudates were tested, and changes of laterite microstructure were observed. Interaction mechanism between water and laterite was opened out, so historical statistical data was further confirmed why service life of laterite dam is always too short.

Reinforcement using alkali substance produces plentiful calcium hydroxide, and calcium hydroxide has engendered long-term demolishment in laterite embankment. Particle contents were analysed and significant ions were tested at demolished laterite in embankment, and chemical reactions of acidic laterite with calcium hydroxide were canvassed. Accelerated life tests were performed, changes of basilic engineering indexes and content changes of significant ions were tested in laterite fore-and-aft demolished. Mechanism of laterite embankment scathed by calcium hydroxide was explored. Acid-alkali reaction is rootstock of benefit descending and life shortening, and is important inducement of permeability exacerbating in laterite embankment.

Water of reservoirs shows acidity in laterite regions, and laterite engineering is chronically demolished by chloride ions in water. Ground on mechanism analysis, accelerated life tests were implemented. After permeability test, changes of grain-size-gradation were analysed at laterite remainder, microstructures of soil sample were observed, and concentration changes of iron ion as well as aluminum ion were affirmed in transudatory liquid. The harvests indicated that: sesquioxides (viscous substances in laterite) are consumed by chloride ions in water, and microstructures of laterite are demolished. Products from chemical reaction are dissolved by water and are schlepped off by seepage, so wispy leakage channels are created in engineering. The eroding of chloride ions has clearly debased security of laterite engineering.

This paper analyzes the problems which exist in finite element calculations of the earth dam seepage which is free surface solution, cell subdivision improper, the transformation of the free surface boundary conditions and the permeability coefficient values at the interface of different materials, boundary conditions and other issues. Put forward the corresponding solution. Applies common general finite element software to calculate the seepage. Works in conjunction with a stable levee seepage analysis and get better results.

Laterite contacted with alkaline materials, was significantly corroded under same conditions, it to be found in the processes of dam safety identification. Alkaline materials properties and acid-alkali reaction were analysed, and supersaturation emulsion calcium hydroxide was used to immerse laterite at constant temperature. Then changes of ion concentration were detected in exudates, change trends of grain size gradations were analysed, and evolutions of pore were observed in laterite. Mechanism of laterite chronically eroded by alkaline materials is opened out, which is neglected by engineers and has become one of the main reasons why reinforcement benefit is always too low.

There are many factors, such as climate, flood, material, geology, structure, management, to influence dam safety. So dam safety evaluation, involving many fields, is very complicated, and very difficult to establish mathematic model for assessment. Artificial Neural Network (ANN) has many obvious advantages to deal with these problems influenced by multi-factor, consequently is widely used in engineering fields. This paper considered water level, temperature, main factors influencing dam deformation, as random variables, employed ANN and statistical model to establish performance function of dam hidden trouble deformation and abnormal deformation. Then reliability theory was used to analyze dam safety reliability and sensitivity. The results show that temperature has great effect on probability of dam hidden trouble deformation and abnormal deformation than reservoir water level, due to great variability of temperature. Change of Reliability index of dam is contrary to reservoir water level. Temperature, especially average temperature in 10 days and 5 days, has great effect on sensitivity of reliability index than water level.

Dam deformation is characterized with periodicity, tendency, randomicity. So dam deformation can be regarded as sum of periodic deformation, tendency deformation, and random deformation, of which periodic and tendency deformation, gained by deterministic method, are researched sufficiently, but study on random deformation is inadequacy. Because dam random deformation at time t is mainly influenced by dam state at time t-1, little influenced at time t-2 or earlier, dam random deformation can be idealized as stochastic process described by Markov chain. In this paper, a new dam safety monitoring model is established using Markov chain, based on statistic model. First, regression analysis was applied to establish dam deformation statistic model, by which dam deterministic deformation can be obtained. Then dam random deformation component can be gained by subtracting deterministic deformation from total dam deformation. Consequently, by analysis of time series of random deformation, transition probability matrix of random deformation can be obtained and used to analyze dam deformation. Case study showed that this new model is superior to traditional statistic model, and can be applied to establish dam safety monitoring model.