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This article presents a laboratory and field investigation of pull-out resistance of wood bolts in rammed earth heritages. The laboratory testing involved axial tensile tests of four grout specimens prepared in specially designed moulds using PS-F (Potassium Silicate solution-Fly ash) slurry to investigate the performance of anchors. The field testing involved pull-out tests of three wood anchors installed in rammed earth heritages by gravity grouting. Experiments reveal that the failure mode is the pull-out of bolt from grout and average skin friction resistance of bolt–grout interface is approximately 0.34MPa. Load–displacement curves and elastic–residual displacement derived from cyclic loading indicate such anchor system has strong ductility with small elastic deformation and large residual deformation. Bond collapse firstly occurs at the loaded end and then propagates towards the full bonded length. Bond stress distribution is not uniform along the bonded length. Maximum bond stress distributes at the range from 0.3 m to 0.4 m. Emergence of compressive strain in the interface reveals such anchor system enjoys the advantages of both tensile and compressive anchor types, which significantly differs from results from other regular bolts. The research conclusion makes scientific senses to traditional material and craft in rammed earth heritages. [ABSTRACT FROM PUBLISHER]

The work reported here is a systematic study to evaluate the compatibility of using PS-F (potassium silicate with high modulus – fly ash) slurry in the conservation of adobe structures. Firstly, the optimum mixing proportion (0.47) was determined by flow meter. Then the experimental program was divided into two parts: one part studied changes in physical and mechanical properties with increase in setting time by means of the measurement of moisture content, compressive and flexural strength, elastic-wave velocity, density, and porosity; the other part studied the durability of PS-F slurry through temperature and humidity cycles, freeze–thaw cycles, water stability, tensile testing, and alkali resistivity tests. The results show that the consolidation process with the slurry can meet the requirements of conservation applications and provide a timely anchoring force, and the slurry and soil mass of adobe-based structures have good compatibility in physical and mechanical properties. In addition, the slurry can strongly resist freeze–thaw cycles, temperature-moisture cycles, and tensile stress and has a relatively weak resistance to alkali solutions and water immersion. In conclusion, PS-F with a mixing ratio of 0.47 is a suitable slurry for conservation of adobe structures. [ABSTRACT FROM PUBLISHER]

The ginger nut has been used as building materials in Dadiwan site in Qin’an County, Gansu Province, China, and it was confirmed as the earliest lightweight concrete in China. However, the ginger nut is not a proper construction material because it does not contain cementitious components. In this paper, original ginger nut were calcined under different temperatures and the properties of the resultant modified ginger nut were analyzed. 1100 °C was chosen as optimal calcination temperature according to CaO, β-CaSiO 3 and Ca 2 Al 2 SiO 7 content. Based on mortar workability and strength as result of curing time, 0.33 was selected as the optimal water binder ratio of the ginger nut mortar. The results of the mechanical tests revealed that the mortar exhibited ductile behavior, and it is possibly due to the special structure between aggregates and hydration or carbonation products. Finally, several tests carried out to determine weathering resistance abilities of the ginger nut mortar showed that they will probably serve as restoration material for stone or soil relics. [ABSTRACT FROM AUTHOR]