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This paper experimentally investigates the potential use of poplar sawdust as replacement material to sand in semi-dry concrete, manufactured by vibrocompaction and used in concrete masonry blocks. The substitution of sand by wood waste can relieve the scarcity of raw materials and lighten concrete masonry block weight. The introduction of a varying proportion (30, 40, 50 and 60 %) of poplar sawdust in the concrete has a significant influence on its thermophysical and mechanical behavior. The inhibition of hydration of cement with this poplar sawdust has a main influence. It affects the hydrates formed in the concrete and has an impact on the compressive strength at 7 days. This strength decreases significantly with increasing poplar sawdust proportion. But the method of concrete manufacturing by vibrocompaction increases the strength and could decrease the inhibitory effect of wood on the hydration reaction of the concrete. Substitution of 50 % of sand by poplar sawdust in the masonry concrete block manufactured by vibrocompaction is proposed. Indeed, this concrete composition gives similar mechanical strength to that of the conventional manufacture of masonry concrete block.

This paper introduces the explosion-protection performance of a kind of meshy aluminum alloy material in different blank rates and different packed densities. Experiment results show that this material has the best explosion-protection effect when the packed density between 30~35 kg/m3. When the packed density is fixed the pressure increase quickly with the increase of blank rate, the flame becomes smaller after filled with the material so this material can decrease the spread of flame. Besides we get the empirical equation of the packed density, blank rate and pressure.

After a chemical vessel suffering a rupture, BLEVE, fireball, jet fire, and dispersion of toxic substance may be the most common failure ways. Which give rise to a great threat to people’s life, process plants and surrounding environment. This paper presents an overview of the mechanism and the consequences for these failures; finally, ALOHA software simulation resorted to evaluating the consequences for all kinds of hazard, a vertical tank with the size of diameter=10, tank length=20m, containing the propane liquid/gas mixture with a volume of 1571 cubic meters, the mass of the chemical is calculated by the software automatically with a value of 554 tons. All the possible failures have been simulated by the ALOHA software, including：1) leaking tank, chemical is not burning as in escapes into the atmosphere; 2) leaking tank, chemical is burning as a jet fire; and 3) BLEVE, tank explodes and chemical burns in a fireball. Furthermore, there are three types hazard available to analyze the situation that chemical is not burning as it escapes into the atmosphere, they are: a) toxic area of vapor cloud; b) flammable area of vapor cloud; and c) blast area of vapor cloud explosion. The result reveals that the farthest threat zone reaches 2.2km in the case of a fireball triggered by a BLEVE, and the result has been viewed and discussed in details.

A Bayesian network quantitative calculation model for urban natural gas pipelines was established by using the unique logic of a Bayesian network in handling complicated risk systems. By using a natural gas pipeline as an example, failure situations such as single factor polymorphism, double factor polymorphism, and multi-factor polymorphism of a pipeline were quantitatively calculated to obtain the probability of top events and the structural importance of basic factors. The proposed method not only reflects clearly the effects of different factors but also predicts the failure state of urban natural gas pipelines comprehensively and accurately. The results of the proposed method can serve as a significant reference for the risk management and fault processing of city natural gas pipelines.

The experimental research on thermal response of LPG tank exposed to fire is carried out. A experimental apparatus to simulate real accident of LPG tank is designed and manufactured. A series of experiments for different fill levels, different type of tanks subjected to different type of fires are performed with this apparatus. From the results of the experiments, the obvious stratification of temperature in the ladings of the tank is observed. And the pressure is increased due to the stratification. Thermal response of the LPG is affected by various factors such as fire type, tank type and fill level etc. The liquid could be superheated or sub-cooled in fire exposure situation. The pressure can be fitted to time by cube polynomial equation.