EXPANSION ANCHORPART

In a straddling dowel or expansion anchor assembly a spreader is threaded on one end of a bolt so that by turning the bolt the spreader is pulled into an expansion sleeve for spreading it into anchoring contact with the surface of a borehole. The opposite end of the bolt has a shoulder provided by a head or nut. Between the expansion sleeve and the shoulder, a yielding member laterally encloses the bolt and yields at least when a minimum anchoring value of the expansion sleeve has been reached. The yielding member affords a visible indication that the minimum anchoring value has been achieved. A washer is positioned adjacent the shoulder on one end of the bolt. Before the expanding action, the washer is spaced from the shoulder on the bolt by the yielding member or by a separate member, however, as the minimum anchoring value is achieved the washer is displaced relative to the member which spaces it from the shoulder, into contact with the shoulder.