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Penetration of concrete targets was simulated based on self-compiled program generating two-dimensional random aggregate model. Random convex polygons were used to simulate the aggregate particles of concrete, HJC model to describe constitutive relations of the aggregates and mortar while concrete targets are subjected to large strains, high pressure and high strain rate. With this model, the Forrestal's penetration test was simulated by ls-dyna software. By comparing the calculated results with the test data, It is shown that random aggregate model can be applied to simulate the dynamic destruction problems of concrete-like materials.

Background: Decision-making trial and evaluation laboratory (DEMATEL) is a practical and concise method to deal with the complicated socioeconomic system problems. However, there are two defects in original DEMATEL. On the one hand the traditional expert preference expressions can’t reflect the hesitation and flexibility of expert, on the other hand the determination of group experts’ weight usually be expressed the equivalent weight which can’t reflect the scientificality of weight on the behalf of experts’ academic background, capability experience, risk preference and so on. To solve the above problems, a novel Group DEMATEL decision method based on hesitant fuzzy linguistic term sets (HFLTSs) is proposed. Method: Firstly, this paper presents that experts make their judgement on the causal relationship of factors by using a linguistic expression closed to human expression, which can be easily transformed into HFLTSs. Next the hybrid weight of experts are calculated on the base of the initial HFLTSs direct influence matrix (HDIM) according to the hesitant degree and distance between two HDIMs. And the aggregation of each expert’s information is introduced by possibility degree. Then the new group DEMATEL decision method based on HFLTSs are constructed. Finally, an illustrative example is given and analyzed to demonstrate the effectiveness and validation of the proposed approach. Results: This paper demonstrate the heterogeneity of decision experts and the hesitation degree of expert information representation must be taken into account when determining the interaction of factors in complex systems by DEMATEL method. Conclusion: This paper constructs the new amended group DEMATEL which provides a new way to deal with the integration of each expert’s information by the hybrid weight and possibility degree. The methods provides references for determining the importance of complex system factors more scientifically and objectively.

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Through laboratory experiments, the effects of adding different maize straw addictive and proportions in soil on the moisture evaporation characteristics were studied under the condition of different burial depth. Results showed that the relationship between soil moisture diffusivity and soil water content can nice described by an exponential function. Under the same soil water suction, soil water content of treatments with maize straw additive are all higher than pure soil. Between the treatments of soil with 3% maize cob and maize leaf, maize leaf treatment has a better water retention effect, but the difference is little in the treatments with 1% maize straw additive; maize leaf is superior to maize cob in the capacity of inhibiting soil water evaporation, and the treatment with 3% maize leaf in the depth of 0-5 centimeter soil layer can reduce soil moisture evaporation effectively. Keywords: maize straw addictive, soil water diffusivity, buried depth, accumulative soil water evaporation, soil water content