That is, the relatively dense cement and aggregate particles settle, leaving the water near the surface. The worst-case scenario occurs on hot, dry, windy days-in other words, conditions that promote drying. That’s because the alkali concentration isn’t the same everywhere in concrete. By contrast, fine-aggregate popouts occur within a few hours of placement at ambient temperatures and without additional alkalis.Įven with low-alkali cement, popouts can still occur. For example, in ASTM C1260 we crush coarse aggregates to sand size, increase the alkali content of the mortar bars, and raise the temperature to well above normal laboratory temperatures. In evaluating aggregates for their tendency to cause deleterious expansions, we use aggressive methods to accelerate the reactions. However, the timing of the reaction is very different from “classic” alkali-silica reaction, which doesn’t manifest itself until years after concrete placement. It would appear … that the popouts are the result of alkali-silica reactivity involving the opaline microfossils in the shale particles.- Landgren and Hadley They occur in both fine- and coarse aggregate. In this case the reactive aggregates are shale particles. Petrographic examination of popouts in the laboratory showed that they result from alkali-silica reaction. Any patching will be as conspicuous as the popout itself. Once the popout appears, the damage is done and you really can’t fix it. And if you’re building an airfield pavement, debris from popouts would be a hazard to aircraft. However, if you’re placing a large slab for an industrial floor or a big box store, you won’t want it to look like that. In a sidewalk or highway pavement you may be willing to accept some popouts. Both fine- and coarse aggregates can cause popouts. Popouts are unsightly surface defects that may appear a few hours to a few weeks after placement. In Minnesota, Iowa, and South Dakota, we sometimes see aggregate popouts, particularly in concrete flatwork. Aggregate popouts on concrete flatwork can be unsightly. So if your component is in a new window it won't be able to easily access objects in the old one.įortunately GoldenLayout comes with a cross-window eventHub that facilitate communication in a simple and reliable way. JavaScript's global namespace is on a per-window basis. GoldenLayout makes it easy to create production ready apps with multi window support, all the way back to IE 8, but there are a few things you as a developer still needs to consider. So, all good? Can I just use popouts free from care? This fulfils the same-origin policy and keeps programatical communication between windows to a minimum. But more importantly, GoldenLayout allows to use popouts in a way that mitigates most security concerns: by loading the same URL in every window and passing instructions about what to create as GET-parameter. GoldenLayout deals with the cross browser quirks and vendor limitations around popouts – and there are many. How can GoldenLayout make any difference with that? This makes it now very hard for advertisers to annoy you with popup-ads, but even harder for web-apps to use them. Opening new windows from a web-page was traditionally used for aggressive advertisement – until browser-vendors started introducing all sorts of constrains and security features. Almost every office program, graphic suite or text editor supports multi window setups – which makes perfect sense, seeing that it helps a lot with utilising desktop space or using parts of an app as standalone widgets.
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