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Gardn er, D ec 15, 2016 C apillary flow characteris tics of an au togen ic an d au ton om ic healin g agen t for s elf-healin g 3 4 agen ts . B oth techn iqu es prim arily rely on the tran s port of flu id ( w ater or healin g agen t) in a dis crete 3 5 crack to m icrocracked z on es of dam age.3 6 3 7The s election of a healin g agen t is driven m ain ly by cos t an d availability, althou gh it is im portan t that 3 8 its phys ical properties s u ch as vis cos ity, s u rface ten s ion , bon din g characteris tics an d its com patibility 3 9 w ith the cem en titiou s m atrix over tim e, are con s idered du rin g the s election proces s . In gen eral, 4 0 healin g agen ts w ith low vis cos ity an d s ign ifican t capillary poten tial are u s u ally preferred. 4 1 4 2 C om pared to au ton om ic healin g agen ts , au togen ic healin g agen ts s u ch as thos e bas ed on 4 3 s u pplem en tary cem en titiou s m aterials ( Sahm aran et al. 2013) , m in eral adm ixtu res ( hn an d K is hi 4 4 2010) an d geom aterials ( K is hi 2013) afford im proved com patibility w ith the hos t m atrix du e to the 4 5 n atu re of the chem ical com pos ition of the healin g produ cts . M oreover, throu gh the u s e of a 4 6 poz z olan ic m aterial, bon d s tren gths com parable w ith thos e of u n dam aged cem en titiou s m aterials 4 7 m ay be achieved. V aryin g m ethods have been propos ed to em bed au togen ic healin g agen ts in to 4 8 cem en titiou s m aterials . Thes e ran ge from com bin in g them in their n atu ral form w ith other m ix 4 9 1 9 5 order of w eeks / m on ths , w hich are greatly in exces s of the du ration of the tes ts reported herein . 1 9 6 1 9 7The s es s ile drops w ere obs erved for on e hou r follow in g the in itial m eas u rem en t. N egligible chan ge in 1 9 8 the con tact an gle w as obs erved for P C 20 after this on e hou r period, w hils t the w ater an d GGB S( S) 1 9 9 s es s ile drops evaporated after 15 m in u tes of expos u re to the laboratory en viron m en t. 2 0 0 2 0 1 T im e-V is cos ity relation s hip 2 0 2The developm en t of a bes poke vis com eter, as s how n in Figu re 5, des ign ed to exam in e the chan ge in 2 0 3 vis cos ity of the healin g agen t w hen in con tact w ith a cem en titiou s m atrix has previou s ly been 2 0 4 4 3 7

Property owners are facing increasing threats from flooding and in response are likely to turn to products designed to waterproof or 'seal' the outside of the building in an effort to prevent the ingress of flood water. However, very limited research has been conducted on the effect of this sealing action and the consequent hydraulic load acting upon the structure of the building. The theoretical safe application of waterproofing products has been suggested to be between 0.6 and 1 m (published guidance suggests 0.9 m), although the experimental evidence supporting these suggestions is either absent or limited in nature. This paper presents the findings of an experimental programme that has examined the effect of out-of-plane hydrostatic loading on masonry walls typical of domestic or commercial buildings. The study, conducted at 1/6th scale using a geotechnical centrifuge considers wall panels constructed from a variety of masonry units (autoclaved aerated concrete block, brick and brick-block) bound together with two different types of mortar. The wall panels were subject to an axial load representative of 1 storey of loading and were simply supported on all 4 sides. The loadout-of-plane deflection response of the panels was captured by a 3D digital image correlation system, and the water level at failure was compared to that predicted from previous research and the established yield line analysis method with encouraging results. When partial material and load factors were taken into consideration the results illustrated that a safe sealing height of 0.9 m, as quoted in the literature, would generally be inappropriate, whilst the safe sealing height of 0.6 m was not suitable for every case investigated. This supports the need for a suitable approach for the calculation of water levels at failure rather than the use of fixed values given in published literature.