Yes, outdoor benches can be securely bolted directly to concrete slabs, and this is actually the recommended installation method for permanent, theft-resistant outdoor seating. The process requires specific tools and hardware designed for concrete applications. You'll need concrete anchors (such as wedge anchors or sleeve anchors), a hammer drill with a masonry bit matching your anchor size, a wrench, safety glasses, and of course your bench.
Begin by positioning the bench exactly where you want it permanently installed. Mark the anchor hole locations through the bench's mounting holes onto the concrete surface. Using your hammer drill and masonry bit, drill holes into the concrete slab at the marked locations. The holes should be slightly deeper than your anchors' length. Thoroughly clean out all concrete dust from the holes using a brush or compressed air - this is crucial for proper anchor grip.
Insert your concrete anchors through the bench's mounting holes and into the drilled concrete holes. Tighten the nuts with a wrench until the bench feels completely secure. Be careful not to overtighten, as this could strip the threads or damage the concrete. For heavy-duty applications or high-traffic areas, consider using epoxy anchors for maximum holding power. Always wear protective eyewear during drilling to prevent concrete particles from entering your eyes. This installation method creates a sturdy, permanent seating solution that withstands weather elements and prevents theft or displacement.